[cctalk] Re: Friden (was Silly question about S-100 and video monitors)

[Adrian Godwin via cctalk]

Yes, that's what I mean.

Of course, it's no good for income-generating things but if all you want to
do is make the design available, it's much less hassle than buying stocks
of pcbs and mailing them out for minimal profit. It pushes the hassle of
doing that onto the recipient but without the added errors of them
downloading your design and sending gerbers off.


On Mon, Sep 4, 2023 at 12:03 AM Paul Koning  wrote:

>
>
> > On Sep 3, 2023, at 5:34 PM, Adrian Godwin via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > OSHPArk and PCBWay will hold your design and let other people buy them
> (if
> > you wish). This is an excellent way to do cheap on-demand distribution. I
> > don't believe Jlcpcb offer this.
>
> OSHpark lets you post your design as an open design, and then others can
> just order their own for the standard OSH price.  Is that what you meant by
> "buy"?  It doesn't mean buy in the sense of money going to the designer.
>
> For my purposes this is just what I want, and I have posted my 3 boards
> there.
>
> paul
>
>
>

[cctalk] Re: Friden (was Silly question about S-100 and video monitors)

[Adrian Godwin via cctalk]

On Mon, Sep 4, 2023 at 12:33 AM ben via cctalk 
wrote:

>
> I guess the era of kit building is long gone.
>
>
Sadly, yes. The cost of bagging up all the components is large compared
with the automated assembly cost, and many people are unwilling to do
surface mount manually. Through-hole is possible for some designs but very
restricting.

What may be feasible is having all the surface mounted parts assembled onto
a pcb and leaving through-hole parts such as pots, connectors etc. to the
builder. The SMT guys don't like doing that part.

[cctalk] Re: Friden (was Silly question about S-100 and video monitors)

[Adrian Godwin via cctalk]

OSHPArk and PCBWay will hold your design and let other people buy them (if
you wish). This is an excellent way to do cheap on-demand distribution. I
don't believe Jlcpcb offer this.

On Sun, Sep 3, 2023 at 10:32 PM Adrian Godwin  wrote:

> I had a couple of boards from OSHPark. They seemed a bit slower : it took
> them longer to accumulate enough board orders to fill their panel needs.
> For a very small board (same size as an HPIB connector) they were
> excellent. Cheap, and postage included whereas the Chinese suppliers have
> expensive postage (unlike what we're used to from ebay).
>
> However, a bigger board (still only 50mm square) was a lot more expensive.
> They don't seem to have the 'cheap if it's under 100mm square' rule that
> the Chinese suppliers do.
>
> From here (UK) it seems you need to calculate in detail to choose the
> optimum for size and postage.
>
> On Sun, Sep 3, 2023 at 10:04 PM Paul Koning via cctalk <
> cctalk@classiccmp.org> wrote:
>
>>
>>
>> > On Sep 3, 2023, at 4:47 PM, Chuck Guzis via cctalk <
>> cctalk@classiccmp.org> wrote:
>> >
>> > On 9/3/23 13:28, Paul Koning via cctalk wrote:
>> >
>> >> I like OSHPark, US based and pretty quick, decent pricing.  Low enough
>> I haven't felt compelled to look for cheaper alternatives.  One nice
>> feature is that they take KiCAD board files directly, no need to generate
>> the low level Gerber files.  One oddity is their purple (or black) solder
>> mask, but one gets used to it.  2 or 4 layers and some other variations.
>> >>
>> >
>> > PCVWay will give you purple (or several other colors) for an extra
>> charge.
>> >
>> > I think there's a link on the KiCAD PCB layout menu send your design to
>> > PCBWay--or at least there was; I haven't checked lately.
>> >
>> > At one time, I thought that OSHPark (and I've used them) did all of
>> > their production domestically, but someone told me that it's not
>> > true--they send out their work to China, just like everyone else.
>>
>> That certainly isn't what their website says -- "about us" says
>> specifically "manufactured in the USA".
>>
>> paul
>>
>>
>>

[cctalk] Re: Friden (was Silly question about S-100 and video monitors)

[Adrian Godwin via cctalk]

I had a couple of boards from OSHPark. They seemed a bit slower : it took
them longer to accumulate enough board orders to fill their panel needs.
For a very small board (same size as an HPIB connector) they were
excellent. Cheap, and postage included whereas the Chinese suppliers have
expensive postage (unlike what we're used to from ebay).

However, a bigger board (still only 50mm square) was a lot more expensive.
They don't seem to have the 'cheap if it's under 100mm square' rule that
the Chinese suppliers do.

From here (UK) it seems you need to calculate in detail to choose the
optimum for size and postage.

On Sun, Sep 3, 2023 at 10:04 PM Paul Koning via cctalk <
cctalk@classiccmp.org> wrote:

>
>
> > On Sep 3, 2023, at 4:47 PM, Chuck Guzis via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > On 9/3/23 13:28, Paul Koning via cctalk wrote:
> >
> >> I like OSHPark, US based and pretty quick, decent pricing.  Low enough
> I haven't felt compelled to look for cheaper alternatives.  One nice
> feature is that they take KiCAD board files directly, no need to generate
> the low level Gerber files.  One oddity is their purple (or black) solder
> mask, but one gets used to it.  2 or 4 layers and some other variations.
> >>
> >
> > PCVWay will give you purple (or several other colors) for an extra
> charge.
> >
> > I think there's a link on the KiCAD PCB layout menu send your design to
> > PCBWay--or at least there was; I haven't checked lately.
> >
> > At one time, I thought that OSHPark (and I've used them) did all of
> > their production domestically, but someone told me that it's not
> > true--they send out their work to China, just like everyone else.
>
> That certainly isn't what their website says -- "about us" says
> specifically "manufactured in the USA".
>
> paul
>
>
>

[cctalk] Re: VCFMW vendor tables

[Adrian Godwin via cctalk]

Any proprietary interface or message database is anathema to honest
communication. And even if they currently have benevolent commercial
policies there's always the possibility of another twitter-style
regression.

Moguls love communication platforms and always have, from Randall Hearst
onwards, because they provide the means to control the conversation and
resulting attitudes.


On Fri, Sep 8, 2023 at 7:14 PM Liam Proven via cctalk 
wrote:

> On Wed, 30 Aug 2023 at 17:25, Seth Morabito via cctalk
>  wrote:
> >
> > I swear to God, Discord will be the end of the open Internet, it's where
> information goes to die. I hate it with every fiber of my being. And yes, I
> use it, I'm on many servers. I'm still allowed to detest it.
>
> 100% agreement from this end.
>
>
> --
> Liam Proven ~ Profile: https://about.me/liamproven
> Email: lpro...@cix.co.uk ~ gMail/gTalk/FB: lpro...@gmail.com
> Twitter/LinkedIn: lproven ~ Skype: liamproven
> IoM: (+44) 7624 277612: UK: (+44) 7939-087884
> Czech [+ WhatsApp/Telegram/Signal]: (+420) 702-829-053
>

[cctalk] Re: Silly question about S-100 and video monitors

[Adrian Godwin via cctalk]

Singer certainly had a place in early computing. But was it the same Singer
that made sewing machines ?


On Fri, Sep 1, 2023 at 5:02 PM Tony Duell via cctalk 
wrote:

> On Fri, Sep 1, 2023 at 4:51 PM dwight via cctalk 
> wrote:
> >
> > My first computer was a Poly-88. I had no monitor and no keyboard.
> > I read and understood the instructions about finding a TV that used a
> transformer power supply. Many newer TV's of that day were not using a
> transformer for the main supply. I went to several secondhand stores and
> found one that would work.
>
>
> The original TRS-80 model 1 monitor was based on a live-chassis (hot
> chassis?) RCA TV set. The USA version had an optoisolator circuit on
> the video input, the  LED driver circuit was powered from the +5V line
> in the computer (hence the +5V on one pin of the video DIN socket). As
> the TV was designed for 115V mains only, the European version has a
> step-down transformer on the AC input. They used an isolating
> transformer, meaning there was no need to isolate the video input in
> the European models.
>
> Philips made a viewdata termal set where the colour monitor was a
> modified KT3 television. The power supply in that starts by bridge
> rectifying the mains input, meaning the chassis is dangerously live no
> matter which way round the mains is connected. The solution to that
> was a 240V 300mA (or so) secondary winding on the mains transformer in
> the the viewdate terminal unit. This provided an isolated AC supply to
> the monitor, so the chassis of the latter could be earthed.
>
>
>
>
>
> > The keyboard was from a surplus Singer data entry machine ( I thought
> they only made sewing machines ).
>
> Didn't Singer own Friden (or at least the name) at one point? I am
> sure I've seen calculators batched 'Singer Friden'). And  I have a
> telecoms test tone genrator that's badged 'Singer' (I assume the same
> company)
>
> -tony
>

[cctalk] Re: Friden (was Silly question about S-100 and video monitors)

[Adrian Godwin via cctalk]

Interesting that processors are getting wider and wider, whilst (perhaps
not in the same timeframe)  we have moved away from parallel interfaces
towards serial ones. I know there are reasons for that in
operations-per-cycle and the difficulty of synchronising wide busses
off-chip but I wonder if those sweetspots will change again.

On Fri, Sep 1, 2023 at 6:53 PM Rick Bensene via cctalk <
cctalk@classiccmp.org> wrote:

> Just to add, interestingly, Singer also purchased General Precision from
> Librascope.
> Librascope/General Precision were the folks that had earlier acquired
> Royal-McBee.  Royal-McBee developed the wonderful (some consider the first
> "personal" computer) LGP-30 vacuum-tube, magnetic drum computer that was
> designed by Manhattan Project theoretical physicist Stanley Frankel.
>
> Frankel had quite a legacy in the world of computing, having contributed
> to the design of the delay-line-based Packard Bell PB-250(with Max
> Palevsky), and development of a custom high-speed computer for Continental
> Oil Company called CONAC (used for data reduction of sounding operations
> search for oil deposits).
>
> Frankel also developed an early electronic calculator design that was
> purchased by Smith Corona/Marchant (SCM) and produced as the CRT-display
> SCM Cogito 240 calculator, augmented with Square Root as to Cogito 240SR.
>
> Frankel also collaborated with SCM on the development of the logic for the
> first set of LSI integrated circuits that were used in the later Nixie-tube
> display Cogito calculators.
>
> He also developed a very interesting calculator, based somewhat on the
> principles of the LGP-30 computer for Diehl in West Germany.   The machine
> was fully transistorized and used only 142 transistors in its logic.  It
> was based on magnetostrictive delay lines (two of them), and was a fully
> microcoded architecture, I believe the first electronic calculator to be
> completely microcoded.
>
> Since read-only memory (for the microcode) was either physically very
> large, or complex and expensive to build at the time (diode ROM, wire rope
> ROM), the microcode was loaded into the calculator at power-up time from a
> two channel punched metal tape.   One channel provided the clocking, and
> the other channel provided the bits.
>
> It took just under a minute from when the calculator was powered on until
> the microcode was loaded into a delay line, and from there, all operations
> of the machine were controlled by the microcode in the delay line.
>
> The machine was able to be implemented with so few transistors because the
> microcode word was quite wide, and was designed so that it was sequentially
> interpreted as the bits streamed out of the delay line, so not all that
> many flip flops were needed.  Working registers were stored in the other
> delay line, along with program steps (yes, the machine was programmable).
>
> The design was very elegant.The machine debuted as the Diehl
> Combitron, and the cool thing about its design was that it was really easy
> to augment by just changing the microcode tape (which was quite easily
> done...bugfixes could be easly installed even by end-users, though such was
> discouraged).
>
> Soon after the Combitron was introduced, an augmented version was
> introduced called the Combitron-S that added a small amount of  I/O
> circuitry and additional microcode to implement operations to allow the
> addition of an external punched paper tape reader/punch.
>
> An interesting aspect of electronic calculator history is that there are a
> number of people whose names pop up at various points in time during the
> evolution of the technology.  Frankel was one of those, along with a cast
> of a few others, all of whom had major impacts in the realm of electronic
> calculator (and the eventual evolution of the electronic calculator into
> what became the microcontroller/microprocessor that spurred the development
> of the personal computer).
>
>

[cctalk] Re: Greaseweazle part 2

[Adrian Godwin via cctalk]

An interesting update on greaseweazle. As I understand this it now supports
LIF at the file level as well as at the disc format level.

https://www.youtube.com/watch?v=8OLdqJqJ490


On Sun, Jun 25, 2023 at 9:43 AM Tony Duell via cctalk 
wrote:

> On Sun, Jun 25, 2023 at 8:31 AM r.stricklin via cctalk
>  wrote:
> >
> >
> > > On Jun 24, 2023, at 11:10 PM, Tony Duell via cctalk <
> cctalk@classiccmp.org> wrote:
> > >
> > > And this is where I get lost..
> > >
> >
> > I do not understand your overbearing attitude of helplessness toward
> this project. I have known you on many occasions to go to far greater
> lengths to achieve far deeper understanding of far more complicated
> devices. Far less intelligent people than you have managed somehow to
> marshal the necessary resources to make useful headway with the damn thing.
> The majority of the questions you’re demanding answers to seem to me like
> the kind of questions that could be easily answered with about four
> minutes’ worth of simple experimentation.
>
> It's a combination of things :
>
> I regard the Greaseweazle (or any other similar device) as a tool to
> help me to do something which I enjoy -- running classic computers.
> While I am happy to spend time improving my skills at using tools, I
> do not expect to have to guess at what the designer was doing.
>
> I also want to understand what my tools should be doing. Not what they
> seem to have done in the past. Getting some of my classics running is
> a big enough ob without having to worry whether or not some missing
> option in writing the boot disk image to a real disk has caused that
> disk to be mangled. The more I know to be correct, the better. I can
> sit down with the Greaseweazle board, the PC, a floppy drive and a
> logic analyser and probably find some combination of options that
> produces what look to be sensible signals on the Write Data line. But
> whether they are sensible signals is a much bigger problem.
>
> Yes, I like solving puzzles. But this shouldn't be a puzzle. If I want
> to solve a puzzle about reading and writing arbitrary disk formats the
> I'll design my own device to do it.
>
> -tony
>

[cctalk] Re: Greaseweazle part 2

[Adrian Godwin via cctalk]

I should say that that's actually the Fluxengine software in combination
with the Greaseweazle hardware.

On Wed, Nov 1, 2023 at 11:19 AM Adrian Godwin  wrote:

> An interesting update on greaseweazle. As I understand this it now
> supports LIF at the file level as well as at the disc format level.
>
> https://www.youtube.com/watch?v=8OLdqJqJ490
>
>
> On Sun, Jun 25, 2023 at 9:43 AM Tony Duell via cctalk <
> cctalk@classiccmp.org> wrote:
>
>> On Sun, Jun 25, 2023 at 8:31 AM r.stricklin via cctalk
>>  wrote:
>> >
>> >
>> > > On Jun 24, 2023, at 11:10 PM, Tony Duell via cctalk <
>> cctalk@classiccmp.org> wrote:
>> > >
>> > > And this is where I get lost..
>> > >
>> >
>> > I do not understand your overbearing attitude of helplessness toward
>> this project. I have known you on many occasions to go to far greater
>> lengths to achieve far deeper understanding of far more complicated
>> devices. Far less intelligent people than you have managed somehow to
>> marshal the necessary resources to make useful headway with the damn thing.
>> The majority of the questions you’re demanding answers to seem to me like
>> the kind of questions that could be easily answered with about four
>> minutes’ worth of simple experimentation.
>>
>> It's a combination of things :
>>
>> I regard the Greaseweazle (or any other similar device) as a tool to
>> help me to do something which I enjoy -- running classic computers.
>> While I am happy to spend time improving my skills at using tools, I
>> do not expect to have to guess at what the designer was doing.
>>
>> I also want to understand what my tools should be doing. Not what they
>> seem to have done in the past. Getting some of my classics running is
>> a big enough ob without having to worry whether or not some missing
>> option in writing the boot disk image to a real disk has caused that
>> disk to be mangled. The more I know to be correct, the better. I can
>> sit down with the Greaseweazle board, the PC, a floppy drive and a
>> logic analyser and probably find some combination of options that
>> produces what look to be sensible signals on the Write Data line. But
>> whether they are sensible signals is a much bigger problem.
>>
>> Yes, I like solving puzzles. But this shouldn't be a puzzle. If I want
>> to solve a puzzle about reading and writing arbitrary disk formats the
>> I'll design my own device to do it.
>>
>> -tony
>>
>

[cctalk] Re: Good C to FPGA/PLA compiler

[Adrian Godwin via cctalk]

There are now some open source tools for working with fpgas. They started
with the ice40 but have now been extended to cover others such that it's
worth googling for free fpga tools rather than going to a single site.

example
https://www.digikey.co.uk/en/maker/projects/introduction-to-fpga-part-2-toolchain-setup/563a9518cd11466fb6a75cf3cb684d6d


On Sat, Sep 23, 2023 at 2:30 AM Martin Bishop via cctalk <
cctalk@classiccmp.org> wrote:

> Paul
>
> I endorse your point regarding Lattice's gouging.  Support for anything
> prior to the XO parts now costs a significant premium.  Their XO2 parts are
> the most useful to this community - free tools and 0.5 mm pitch, e.g. 100p
> & 144p - not dense but usefully large, 3v3 IO and agricultural assembly.
>
> The Xilinx free tools no longer have license files, which was how Lattice
> cut us all off at the pass.  The current Vivado ML Standard Edition (tools
> to normal people) are free up to the XC7Z030 - which is a fairly serious
> device.  I have a PDP-11 and space to spare running in the markedly smaller
> XC7Z010; 16b / no MMU, most of the 45 instruction set.  FPGA are
> (organically) memory poor - perhaps because the access time is ~3 ns.  I
> should think you would be in with a chance of fitting the 6600 logic,
> however on a '30 you have 265 x 4 ki by BRAMs = ~1 Mi By, if more is
> required either a dedicated external memory device or DMA to/fr DRAM would
> be required.
>
> Martin
>
> -Original Message-
> From: Paul Koning [mailto:paulkon...@comcast.net]
> Sent: 23 September 2023 01:46
> To: cctalk@classiccmp.org
> Cc: Martin Bishop 
> Subject: Re: [cctalk] Good C to FPGA/PLA compiler
>
>
>
> > On Sep 22, 2023, at 3:59 PM, Martin Bishop via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > 100% disagree, Verilog and SV are bad tools - very easy to do a bad job
> with - penknife grade.
> >
> > Verilog however is very c like in that it is untyped and prone to all
> the consequent tar pits; see above.
> >
> > VHDL is a good tool which is typed and like the Algol family of
> languages precludes many follies.
> > The 2008 flavor, which is where the tools are curently, is not as
> pedantic as the older standards '97 & '83.
>
> I only know VHDL but I had heard that Verilog is C-like, and yes, C offers
> an unusually large set of tools to shoot yourself in the foot with.  So it
> wouldn't surprise me that Verilog does likewise, which certainly means that
> it would be the option to avoid.
>
> VHDL is very clearly based on Ada, which like Pascal and ALGOL takes data
> types seriously rather than only as suggestions the way C does.  I've built
> some very large designs with VHDL, but not because I actually wrote that
> much code -- a lot is generated code produced from wire lists.  But I did
> write all the models of all the 6000 modules, which does add up.
>
> Apart from vendor tools for producing bits for particular FPGAs, you can
> also find VHDL simulators that just simulate a model but don't deliver it
> to a particular chip.  I use GHDL, which is part of the GCC toolset.  Yes,
> a VHDL compiler, interesting.  Among other things, it allows you to link
> bits in other languages, so I can take device models from the DtCyber
> emulator and attach them to a VHDL-modeled I/O channel.
>
> On FPGAs, it's worth checking what the story is for vendor tools.  Some
> devices and vendors try to suck large sums of money out of you for them;
> Lattice is an example.  Even for small devices (like the ispLSI2032 I used
> years ago) that expense adds up rapidly.  I think they have become somewhat
> more reasonable now, offering free tools for the smaller devices.  I know
> Xilinx does so, and "smaller" covers a surprising amount of capacity these
> days.  I'm pretty sure a PDP-11 model would fit fine in one of those "free
> tool" devices, though a CDC 6600 probably won't.
>
> paul
>
>
>

[cctalk] Re: Tadpole/RDI UltraBooks - UNIX notebooks - species needs rescue...

[Adrian Godwin via cctalk]

There are solutions to the dying DS chips. I have seen replacement with
newer ones (but sometimes those have old cells too), surgery to replace the
internal cell https://www.youtube.com/watch?v=kZJDlNoJk7M, and replacement
with a clone https://www.tindie.com/search/?q=dallas.

However the critical thing would be to replace the data with something that
doesn't hang on booting (perhaps even incorrect information from another
unit would be close).


On Sun, Sep 24, 2023 at 5:23 PM erik--- via cctalk 
wrote:

> Just checked the datasheets: The NVRAMs of the UltraBooks I know of are
> the DS1643 and the DS1553. Both should be similar enough to be read/write
> by any reader that supports the DS1643 or the DS1553. Of course I'd offer
> creating an modified Arduino doing the task, to test it and to supply it to
> anyone who is willing to dump his NVRAM!!!
>

[cctalk] Re: VT100: Failing 2114 Chip Replaced With One With The Same Fault

[Adrian Godwin via cctalk]

Another possible approach is to trigger the logic analyser on a write
access to that ram address, preferably with the probes on the ram itself.
Look at the resulting captures .. does  it seem consistent with the code
and other accesses ?


On Sun, Oct 8, 2023 at 12:35 PM Adrian Godwin  wrote:

> Do you have one of those eprom programmers which also do device checks ?
> They might do a check of the supposed faulty ram out of circuit. If you
> don't have one you could probably write one for any convenient device you
> have to hand such as an arduino. Exercising the ram with port writes will
> be painfully slow compared with a normal ram test but with only 2K to test
> it shouldn't take too long.
>
>
> On Sun, Oct 8, 2023 at 9:35 AM Rob Jarratt via cctalk <
> cctalk@classiccmp.org> wrote:
>
>>
>>
>> > -Original Message-
>> > From: wrco...@wrcooke.net 
>> > Sent: 08 October 2023 04:15
>> > To: r...@jarratt.me.uk; Rob Jarratt via cctalk 
>> > Subject: Re: [cctalk] VT100: Failing 2114 Chip Replaced With One With
>> The
>> > Same Fault
>> >
>> >
>> >
>> > > On 10/07/2023 5:35 PM CDT Rob Jarratt via cctalk <
>> cctalk@classiccmp.org>
>> > wrote:
>> > >
>> > >
>> > > I find this really hard to explain. It can't be the chip selection
>> > > logic because then the addresses 0x2400-0x2407 would also fail and I
>> > > checked the CS signal with the logic analyser just to be sure. I also
>> > > checked the address lines directly on the RAM chip for any stuck bits
>> > > and they seemed fine too.
>> > >
>> > >
>> > >
>> > > What are the chances of two 2114 chips failing at exactly the same
>> address?
>> > > Is there some failure mode I might not be considering?
>> > >
>> > > Rob
>> >
>> > Perhaps it isn't the 2114 or its associated circuit at all.  Maybe some
>> other
>> > device is being incorrectly selected by that address and driving (half)
>> the bus
>> > low?  Just a thought.
>>
>> Many thanks for the suggestion. This hadn't crossed my mind, so I
>> checked. All the things that I could identify on the schematic that connect
>> to the bus (UART, interrupt vector, flag buffer and modem signals) seem not
>> to be enabled. I have looked at what is sinking the data bus, there is a
>> buffer which seems to be OK and the 8251 PIC. The PIC is harder to check
>> but I can see it is not selected and the input pins don’t appear to be
>> shorted.
>>
>> Not really sure what else to consider.
>>
>> >
>> > Will
>> >
>> > If you want to build a ship, don't drum up people to collect wood and
>> don't
>> > assign them tasks and work, but rather teach them to long for the
>> endless
>> > immensity of the sea.
>> >
>> > Antoine de Saint-Exupery
>>
>>

[cctalk] Re: VT100: Failing 2114 Chip Replaced With One With The Same Fault

[Adrian Godwin via cctalk]

Do you have one of those eprom programmers which also do device checks ?
They might do a check of the supposed faulty ram out of circuit. If you
don't have one you could probably write one for any convenient device you
have to hand such as an arduino. Exercising the ram with port writes will
be painfully slow compared with a normal ram test but with only 2K to test
it shouldn't take too long.


On Sun, Oct 8, 2023 at 9:35 AM Rob Jarratt via cctalk 
wrote:

>
>
> > -Original Message-
> > From: wrco...@wrcooke.net 
> > Sent: 08 October 2023 04:15
> > To: r...@jarratt.me.uk; Rob Jarratt via cctalk 
> > Subject: Re: [cctalk] VT100: Failing 2114 Chip Replaced With One With The
> > Same Fault
> >
> >
> >
> > > On 10/07/2023 5:35 PM CDT Rob Jarratt via cctalk <
> cctalk@classiccmp.org>
> > wrote:
> > >
> > >
> > > I find this really hard to explain. It can't be the chip selection
> > > logic because then the addresses 0x2400-0x2407 would also fail and I
> > > checked the CS signal with the logic analyser just to be sure. I also
> > > checked the address lines directly on the RAM chip for any stuck bits
> > > and they seemed fine too.
> > >
> > >
> > >
> > > What are the chances of two 2114 chips failing at exactly the same
> address?
> > > Is there some failure mode I might not be considering?
> > >
> > > Rob
> >
> > Perhaps it isn't the 2114 or its associated circuit at all.  Maybe some
> other
> > device is being incorrectly selected by that address and driving (half)
> the bus
> > low?  Just a thought.
>
> Many thanks for the suggestion. This hadn't crossed my mind, so I checked.
> All the things that I could identify on the schematic that connect to the
> bus (UART, interrupt vector, flag buffer and modem signals) seem not to be
> enabled. I have looked at what is sinking the data bus, there is a buffer
> which seems to be OK and the 8251 PIC. The PIC is harder to check but I can
> see it is not selected and the input pins don’t appear to be shorted.
>
> Not really sure what else to consider.
>
> >
> > Will
> >
> > If you want to build a ship, don't drum up people to collect wood and
> don't
> > assign them tasks and work, but rather teach them to long for the endless
> > immensity of the sea.
> >
> > Antoine de Saint-Exupery
>
>

[cctalk] Re: Logic Analyzers - HP/Agilent 16700B or 1670G?

[Adrian Godwin via cctalk]

There have been a few threads very recently in
https://groups.io/g/HP-Agilent-Keysight-equipment which you would probably
find interesting.
There is a lot of enthusiasm over the 1670 and 16700 machines - I wouldn't
say you've missed the sweet spot since these are now often much cheaper
than the later 168x and 169x machines but still very well liked : not least
because the 167x are based on HPUX rather than Windows.


On Sun, Aug 20, 2023 at 8:43 PM Glen Slick via cctalk 
wrote:

> On Sun, Aug 20, 2023, 12:05 PM John H. Reinhardt via cctalk <
> cctalk@classiccmp.org> wrote:
>
> > Hello all.  I looking around for a Logic Analyzer for doing (mostly) DEC
> > QBus/UniBus stuff.  Being the way I am I want something with enough lines
> > to handle the most of the signals so I'm guessing something with roughly
> > 80-ish channels.  I think that lets out all/most of the USB based LA.
> I've
> > looked around and it seems the the HP/Agilent 16700 series
> (16700B/16702B)
> > are probably what I want.  I've also seen the 1670G which also seems
> quite
> > doable.  I've seen a lot of posts at the EEVblog and it seems I missed
> > possibly the golden age of 16700 LA by a few years price-wise.
> >
> > What I'm wondering is if there is something specific I should be looking
> > for, or opinions on which LA is more suitable.  Or even if there is a
> > different make of LA to look for.
> >
> > Thanks in advance for your help
> >
> > John H. Reinhardt
> >
>
> Where are you located? That can have a large impact on the cost of
> acquiring a large 16700-series logic analyzer. For example, I have more of
> those than I need in the Seattle area. A local deal might work out well,
> but if shipping is involved that can quickly get too expensive.
>
> If bench space is limited, a 1670G takes up a lot less, and is completely
> self contained and easier to move around and set up. On the other hand, a
> 16700-series is more flexible, and if you have space to set up an external
> monitor you can see a lot more data on the screen at the same time without
> scrolling around.
>

[cctalk] Re: Good Inventory Program

[Adrian Godwin via cctalk]

It doesn't really add any proper database features (though there may be
extensions) but I use mediawiki for cataloguing mixed information. It's
good at just adding things to the structure and still providing a
searchable store.


On Wed, Aug 16, 2023 at 3:19 PM Hans-Ulrich Hölscher via cctalk <
cctalk@classiccmp.org> wrote:

> I tried DSM (MUMPS) once, but when you grew up with relational databases,
> you're spoilt for a lifetime (for using DSM)!
>
> Ulli
>
> Chris Zach via cctalk  schrieb am Mi., 16. Aug.
> 2023, 16:04:
>
> > Just use DATARIEVE.
> >
> > (Sometimes known as DATAHEAVE)
> >
> > On 8/16/2023 1:49 AM, Evan Linwood via cctalk wrote:
> > > This is almost an impossible question to answer (!) but it might be
> > worth mentioning Pimcore. This is an open source master data management
> > tool, meaning that it supports both schema (data model) design and
> > generation/design of UI elements via a reasonably decent management
> > interface.
> > > It might even be overkill for this particular use case., but from
> memory
> > the web UIs that it generates don’t depend on front end libraries /
> Angular
> > / React etc & so may work with older browsers.
> > > Perhaps another option is LibreOffice Base?
> >
>

[cctalk] Re: Philips P2000C add-ons.

[Adrian Godwin via cctalk]

On Tue, Jan 24, 2023 at 5:09 PM Tony Duell via cctalk 
wrote:

> A couple of questions if anyone has experience of this machine :
>
> 1) There is a 5 pin DIN socket for connecting an external video
> monitor. The signals seem to be TTL-level separate syncs at European
> TV rates (15625Hz horizontal, 50Hz vertical) and separate (not
> composite) 4-level analogue video.
>
> I believe Philips sold a 12" monitor to connect there. What was the
> model number? Is a service manual availabe?
>
> Has anybody linked other monitors to that socket?


Hi Tony,
I enjoyed the restoration description :)

Maybe the popular CM8333 ? I think it was also badged - perhaps with a
different interface - as the Commodore 1084.
It kind of took over from the BBC Microvitec Cub (15kHz, TTL RGB) as an
early Archimedes colour monitor.

https://blog.roberthargreaves.com/2016/04/16/cm8833-repair

I have a Logica VTS Kennet 2400 from about 1985. It was an MS-DOS machine
when those could exist without being PC-compatible. It also had SASI  : the
interface isn't much more than buffer and latch, but formed the basis for
SCSI. We used either a Xebec controller or Adaptec. with ST506 discs. It's
a very simple interface,  a subset and predecessor of SCSI I think. I have
extensive manuals for the machine which include the SASI interface  and the
command set. I did have a SASI controller on it at one time - it might
still be there.

[cctalk] Re: Philips P2000C add-ons.

[Adrian Godwin via cctalk]

On Tue, Jan 24, 2023 at 6:46 PM Tony Duell  wrote:

> >>
> >> 1) There is a 5 pin DIN socket for connecting an external video
> >> monitor. The signals seem to be TTL-level separate syncs at European
> >> TV rates (15625Hz horizontal, 50Hz vertical) and separate (not
> >> composite) 4-level analogue video.
>
> I know it well, but it is unlikely to be the monitor I am looking for here
> :
>
> It's colour (and the P2000C is clearly a monochrome output).While that
> it no real barrier, I doubt Philips would have wasted a colour CRT in
> that way
>
>  I missed that. So it was pinned for colour but only used mono ?There was
another Philips monitor in the same or similar case. I've seen it in both
Green and Amber phosphors. This was also used on the Beeb when colour was
too expensive. I can't remember the number now though.That was almost
certainly composite though - but it was such a common monitor it's quite
possible there was a separate-sync version.

>
>
> Is it 12"? Something is telling me it's a 14" CRT but I am not gong to
> dig mine out to check. The service manual implies it is over 12"
> diagonal.
>
>
You're right. Mine has 13" visible so probably a 14" tube. And although the
mono might have been smaller, that case shape is so embedded in my memory
that I think they must have been 14" too - a 12" version would have looked
amusingly miniaturised.

>
>

[cctalk] Re: Philips P2000C add-ons.

[Adrian Godwin via cctalk]

!Chassis monitors". Built for things like ATMs.

On Tue, Jan 24, 2023 at 9:12 PM Bill Gunshannon via cctalk <
cctalk@classiccmp.org> wrote:

>
> On 1/24/2023 2:47 PM, Will Cooke via cctalk wrote:
> >
> > In the US in the late 80s and 90s, there were a crap ton of similar
> monitors (without case) sold on the surplus market.  I had one.
>
>
> Wow, that's a scary memory.  I had one as well.  Don't even remember
> what I used it
>
> for.
>
>
> bill
>
>
>

[cctalk] Re: Philips P2000C restoration

[Adrian Godwin via cctalk]

On Wed, Jan 25, 2023 at 10:27 AM Tony Duell via cctalk <
cctalk@classiccmp.org> wrote:

>
> I've put a few photos of the machine (in bits) in my flickr account here :
>
> https://www.flickr.com/photos/tony_duell/albums/72177720304931970
>
>
>
Nice ! Very thorough cleaning of the  disc drive !
But I'm curious about the eye-bolts. I assume not original. Do you hang it
from the ceiling ?

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Adrian Godwin via cctalk]

My personal experience of graphical programming environments (scratch,
matlab, PLCs,  Max/MSP - though all in quite trivial amounts) is that
they're dreadful. Painfully slow to use and clumsy compared with  straight
C. There are too many possible variants of what you might want to do, so
every simple for-loop block gains a heap of optional parameters which
destroys the point.

One contrary example is node-red, used to design data flows and also for
teensy's audio programming environment. When the main idea is flow and each
block's parameters are either obvious (like filter cut-off frequency) or
inherent in the connections (the lists of parameters that describe where
the data is flowing rom and to) then they can be a help. I'd recommend
playing with the Teensy audio system (you don't need to pay for it) to see
what you think.


On Wed, Jan 25, 2023 at 4:53 PM Steve Lewis via cctalk <
cctalk@classiccmp.org> wrote:

> I'm familiar with Scratch, my daughter used it in elementary.  I had
> forgotten about it though - it seemed focused on the task of depicting and
> moving objects on a 2D area, not so much in general information processing
> (but still, yes it could be a starting point).   One hallmark of a "good
> development environment" that someone once told me is that that development
> environment can be used to create itself.   Like, by Borland Delphi 2, they
> used Delphi to create Delphi.   Same on the Visual Studio development team
> - they compile and develop VS using VS.   So, I wonder if Scratch can
> create itself?   It's not a hard rule, just a casual observation on the
> "robustness" or maturity of a given development environment.
>
> There's always been a kind of "two tiers" of software developers - those
> who can create reusable routines (libraries) and those who can mold
> existing libraries to build applications.  Obviously some can do both, but
> generally the latter get "stuck" if there isn't some existing
> function/routine in an API to do what they need to do -- like open a
> socket, start a thread, or query system time.  The former tends to need to
> sink into OS and HW specifics.
>
> With this "blocked" code floating in VR -- the idea is then "behind the
> code" to show a virtualization of the resources needed by that code, to
> quickly get an idea of the hardware requirements (relative to how many
> resources it is using) and also linkages to other software, to get a feel
> for the overall complexity.These are important metric to see the
> versatility of re-using that code in other environments/platforms.
>
> And back on the stenography-keyboard like thing -- what about morphing
> keys?  If a keyboard had actual screens on the keys, and the keys change
> (the actual symbol) based on the context of whatever you're doing.  I know
> we have macros and reprogrammable keyboards, but morphing the actual symbol
> on the keys might be neat.
>
> Also, does any processor support a dynamic instruction set?  I've wonder if
> some instruction-set optimizer might find improvements by indicating your
> program could be executed more efficiently if such-and-such instruction was
> available.
>
>
>
>
>
> On Tue, Jan 24, 2023 at 11:49 PM Sellam Abraham via cctalk <
> cctalk@classiccmp.org> wrote:
>
> > On Tue, Jan 24, 2023 at 6:41 PM Steve Lewis via cctalk <
> > cctalk@classiccmp.org> wrote:
> >
> > > BTW, I've wondered if some form of stenography could be used for
> software
> > > development.   In my mind, it would make sense to just program directly
> > in
> > > a kind of Abstract Syntax Tree (AST) from the beginning - why bother
> with
> > > all the syntaxic sugar and peddling ascii text characters around a file
> > to
> > > form a program.   So now I wonder if "building" a program using an AST
> > > might be possible in VR.. you "grab" a FOR loop virtually from a box on
> > the
> > > left, add it to your program tree, and build out from there decorating
> > the
> > > tree
> > >
> >
> > Are you familiar with Google Scratch?
> >
> > https://scratch.mit.edu/
> >
> > Add the VR interface and you basically have what you describe.
> >
> > Sellam
> >
>

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Adrian Godwin via cctalk]

Wikipedia claims line printers had achieved 600 lpm by the '50s and have
reached 2500 lpm


On Thu, Jan 26, 2023 at 9:56 PM Chuck Guzis via cctalk <
cctalk@classiccmp.org> wrote:

> On 1/26/23 13:23, Fred Cisin via cctalk wrote:
> > On Thu, 26 Jan 2023, Chuck Guzis via cctalk wrote:
> >
> > Even a daisy wheel is easily capable of twice that.
> > But, we didn't have convenient access to anything better half a century
> > ago.
>
> A couple of years ago, that would have been true.  But the
> Diablo Daisy-wheels date from at least 1972. You're also forgetting the
> thermal printers, like the TI Silent 70, which could sail along at 30
> cps (1971).   There were other variations.  I recall a Singer terminal
> that used a spinning typewheel  (One always ended with a page eject
> because the damned thing would leave a vertical smear of black ink if
> left unattended).  Carriage was unidirectional via wormscrew rod; return
> was via a spring that was stretched as the carriage advanced.   I
> couldn't find anything on bitsavers about this creature, but I used one
> in the early 70s.
>
> --Chuck
>

[cctalk] Re: in need of 2.5" disks

[Adrian Godwin via cctalk]

There was the Amstrad floppy. I think it was 3". Hopefully didn't get out
of the UK.


On Mon, Jan 23, 2023 at 7:47 PM Chris via cctalk 
wrote:

>  Ok the MS used 2" disks. I suspect only Fuji made them. I am that mental.
>
> 245 tpi 720kb. That thing was a beast in it's day. Like a LOTR dwarf
> champion or something.

[cctalk] Re: Age of Tape Formats?

[Adrian Godwin via cctalk]

Some information about the origin of CUTS here :
https://retrocomputing.stackexchange.com/questions/8099/whats-the-difference-between-kansas-city-tape-standard-and-cuts

I recall a Logabax computer (a french office / accounting system that seems
to e completely forgotten) in about 1975 that had a built-in mechanism that
used audio cassettes. The tapes, if played on an audio system, were a
series of tones not unlike CUTS - I guess the idea of recording as audio
something intended to be sent over the telephone system was fairly obvious.

On Wed, Mar 8, 2023 at 12:25 PM Bill Gunshannon via cctalk <
cctalk@classiccmp.org> wrote:

>
> On 3/7/2023 8:30 PM, Dennis Boone via cctalk wrote:
> >   > I’m working on a project, and I need to know the age of various tape
> >   > formats.  For example when were 6250bpi 700’ 9-Track tapes or DC600A
> >   > cartridges introduced?  Is there any good resource online that
> >   > documents this?  Wikipedia is of some help, but the older you go, the
> >   > spottier it is.
> >
> > For QIC, qic.org has a some info.  For DLT and LTO, the wikipedia pages
> > are fairly useful.
>
> What about the data cassettes used on things like Plato?  Not at all
> like the
>
> audio cassettes later used on home computers.
>
>
> bill
>
>
>

[cctalk] Re: on the origin of home computers

[Adrian Godwin via cctalk]

Not really technical, but a couple of presentation points :

There's a long tail to the video with no video and blank audio. After a
while, a section of audio from the main flow is repeated.

It seems to be common to consider Youtube videos more approachable if
they're up to about 10 minutes long. You might benefit by splitting it into
2 parts.

And even further off topic ..  I see that the pictorial guide includes
machines from GB and Japan (and I think a Sharp is mentioned in the
description). Although GB was heavily influenced by USA machines it did
have it's own distinct history and so, I think, did Japan. Russia also had
clones of well known machines and their own designs. Did any other
countries have a history that was more complex than  picking the best known
parts of the international trade ?



On Wed, Mar 8, 2023 at 11:24 AM Steve Lewis via cctalk <
cctalk@classiccmp.org> wrote:

> Greetings,
>
> We're making final touches on a short history-video we've been making about
> home computers (my daughter, in middle school, has been helping).
>
> If anyone has time/interest to do a review, the draft listing is here:
> https://www.youtube.com/watch?v=Z9mgSVJZoFc
>
> Unless anyone spots a gross technical error, we're hoping to render the
> final sometime this weekend or sometime this month.
>
> Thanks,
> Steve
>

[cctalk] Re: on the origin of home computers

[Adrian Godwin via cctalk]

I like that you've included machines like the HP and IBM - sometimes these
histories start with the Altair as  being the first one at an affordable
price, but I'm sure those desktop machines got to a lot of scientific homes
before the enthusiasts machines began to appear.

On Wed, Mar 8, 2023 at 5:05 PM Steve Lewis via cctalk 
wrote:

> Tarek,
>
> > This is awesome, Steve. First of all please give a high five to your
> middle-schooler daughter whom you had her help make such a high
> > quality video. I assume that such videos will also be shared at schools,
> and your daughter’s friends. It would help raise awareness on
> > the history of computers that ultimately led to today’s devices and
> software. For once, our kids can say “aha, so this is where home computers
> came from?” :)
>
> You got it, the hope is to help awareness and be something acceptable for
> schools to use.   And part of this started when my daughter asked me "what
> was the first home computer?"   I just couldn't give a simple answer :)
> She did the background (her signature is at the bottom left, "Carrion" --
> and its subtle, but the gray at the top and bottom was intended to
> represent silica sand) and picked most of the system arrangement.
>
>
> Thanks!
> Steve
>
>
>
> On Wed, Mar 8, 2023 at 9:25 AM Tarek Hoteit via cctalk <
> cctalk@classiccmp.org> wrote:
>
> > This is awesome, Steve. First of all please give a high five to your
> > middle-schooler daughter whom you had her help make such a high quality
> > video. I assume that such videos will also be shared at schools, and your
> > daughter’s friends. It would help raise awareness on the history of
> > computers that ultimately led to today’s devices and software. For once,
> > our kids can say “aha, so this is where home computers came from?” :)
> > In terms of content, I love the wealth of photos that are included. I can
> > see that a lot of research was made for each item. As for the chronology
> of
> > events or machines, there is never a 100% accurate story. Adrian, talked
> > about US, UK, and Japan influence  Yes but then what’s the fine line of
> > telling the story without getting too long and too technical. I think you
> > managed to strike a good balance in your video in terms of content and
> > machines. Well done!
> >
> > Regards,
> > Tarek Hoteit
> >
> > > On Mar 8, 2023, at 3:25 AM, Steve Lewis via cctalk <
> > cctalk@classiccmp.org> wrote:
> > >
> > > Greetings,
> > >
> > > We're making final touches on a short history-video we've been making
> > about
> > > home computers (my daughter, in middle school, has been helping).
> > >
> > > If anyone has time/interest to do a review, the draft listing is here:
> > > https://www.youtube.com/watch?v=Z9mgSVJZoFc
> > >
> > > Unless anyone spots a gross technical error, we're hoping to render the
> > > final sometime this weekend or sometime this month.
> > >
> > > Thanks,
> > > Steve
> >
>

[cctalk] Re: Low cost logic analyzer

[Adrian Godwin via cctalk]

I completely agree about the Saleae devices. Very good software, nicely
made hardware. They're not cheap though, and only go up to 16 channels.

You can capture 16 channels with the very cheap Cypress FX2 dev boards (the
older Saleae devices were pretty much that).
I'd like to find a convenient solution for more width though - I have an
HP16500B but it's huge and noisy. There are one or two possibilities in the
sigrok hardware list but nothing I've tried yet.


On Tue, Mar 14, 2023 at 1:28 AM Jim Brain via cctalk 
wrote:

> On 3/13/2023 8:12 PM, Paul Koning via cctalk wrote:
> > Gents,
> >
> > I've been doing logic debugging (on a fairly primitive software defined
> radio I designed back in 1999) with an old Philips logic analyzer.  It's
> not bad, certainly fast enough (I need 100 Msamples/s, it can do twice
> that) and it's more than wide enough (I need 32 channels).  But its capture
> memory is microscopic so I struggle to see more than one or two
> transactions, and I need to see more than that.
> >
> > Some poking around shows various USB-connected logic analyzers for quite
> low prices, and a number of them seem to have suitable specs.  I also ran
> across sigrok.org which seems to be an open source logic analysis
> framework that can drive a bunch of those devices.  Nice given that too
> many of them only come with Windows software.
> >
> > I suspect there are others that have not too expensive logic analyzers
> and might be able to offer up suggestions or product reviews.
> >
> >   paul
> >
> If you have 8 or 16 channels to watch, the Saleae units are absolutely
> incredible: https://www.saleae.com/
>
> For more channels, I will admit I'm partial to old HP units, especially
> the frames.  I have a 16702A here, which I love.  I have 3 333MHz LA
> boards in it 68 channels per board, 204 channels overall.  It's not
> quite as trivial to use as the Saleae units, but it does offer remote
> access via X or VNC.
>
> Jim
>
> --
> Jim Brain
> br...@jbrain.com
> www.jbrain.com
>
>

[cctalk] Re: Low cost logic analyzer

[Adrian Godwin via cctalk]

Yes, I've used sigrok and sat on their IRC channel for quite a while.
I've used the gpib analyser and extended a DMM driver to cover the hp34401A.
The logic analyser client is probably the best application and is
comparable with Saleae's own client. The streaming cli clients are also
good, but I think the scope client is behind Zonenberg's glscopeclient.

Sigrok is generally pretty good but is suffering developer shortage at
present. The code quality is very good so this doesn't create a bug fixing
issue  but it does mean some recent feature additions haven't made it to
the mainstream. If you (or anyone) has a taste for code reviewing I believe
you'd be very welcome to help.

I've also seen a recent patch to make it easier to use out-of-tree drivers
for this very reason. I don't know much about that but it's an op[tion if
you want to use the rasbperry pico as an acquisition engine.

Open source and cross-platform  credentials are excellent : in fact this
causes a slight problem,  as the Cypress FX3 which would otherwise be a
good candidate as an acquisition engine can only be shipped with
closed-source proprietary blobs, which stops it being used by sigrok.

Any errors in the above are my own..


On Tue, Mar 14, 2023 at 2:39 PM Paul Koning via cctalk <
cctalk@classiccmp.org> wrote:

>
>
> > On Mar 14, 2023, at 1:38 AM, Steve Lewis via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > ...
> > Anyway, as an option slightly cheaper than the Saleae, I'm trying the
> > 32-channel version of the DreamSourceLab U3Pro32.  It's not horrible,
> I've
> > 24 pins hooked up so far.  I debated on if 2x16's would be better.
> > Amazon is good about returns, but this little DSL probe is good enough,
> > I'll be keeping it.
> >
> > DreamSourceLab DSLogic U3Pro32 USB-Based Logic Analyzer with 1GHz
> Sampling
> > Rate, 2Gbits Memory, USB 3.0 Interface, 32 Channels
>
> Thanks everyone.  Some reactions to what I heard:
>
> The U3Pro32 happens to be what I was looking at when I spotted the link to
> sigrok.org.  (Does anyone here have experience with that software?)
> Among other things, it has a long list of supported devices, a lot of logic
> analyzers of various specs, many that look like the sort of low cost
> choices I was looking for.  I saw DreamSourceLab, Hantek, and a bunch of
> others offering 32 bit wide analyzers.
>
> On HP: yes, perhaps.  I used one of those back at DEC, in the mid 1980s.
> Nice machine, but my suspicion is that I'd run into the small memory
> problem again that plagues me with the Philips/Fluke analyzer I use right
> now.
>
> I can see lots of 16 channel options including mixed oscilloscopes.  That
> doesn't work for what I need, because I have (a) a control interface (EPP
> mode parallel port, so that's about 12-14 wires right there) plus the
> resulting internal signals I want to see, plus a serial data link going the
> other way.   32 channels is what I have right now and that's comfortable;
> 16 would mean a lot of fiddling around to keep switching which subset I can
> see.  Also, I have a Tek DAS602 so a new scope isn't all that appealing,
> especially the lower cost ones (much less bandwidth, though admittedly more
> memory) -- and while Rigol is less expensive than Tek it still has a fairly
> substantial price tag.
>
> I noticed the sigrok.org devices list mentions one that is open source
> hardware, that sounds a bit like what Sytse was talking about.
>
> paul
>
>
>
>

[cctalk] Re: PDP-11/05 early print set for download

[Adrian Godwin via cctalk]

I thought it was Mazak too - eg
https://www.ebay.co.uk/itm/Myford-Mazak-hand-dials-ML7-and-ML7R-/325571981560


On Sat, Mar 18, 2023 at 2:54 PM Jon Elson via cctalk 
wrote:

> On 3/18/23 04:34, Steve Malikoff via cctalk wrote:
> > G'day all,
> > I have just uploaded the engineering drawings for the early
> PDP-11/05, the one with the solid (no slots) Mazak lower bezel
>
> Huh?  Mazak made machine tools.  Did you mean Zamak
> (zinc-based die casting alloy)?
>
> Jon
>
>

[cctalk] Re: One of Paul Allen's Museums

[Adrian Godwin via cctalk]

I think museums these days are careful to make sure donations really are
that. Not, probably, because they see a sale in their future but because in
the event of commercial failure they don't want to have to execute
thousands of different disposal requirements.

On Tue, Apr 25, 2023 at 2:55 PM Tarek Hoteit via cctalk <
cctalk@classiccmp.org> wrote:

> Wasn’t his sister busy buying or selling a sports team and showed no
> interests in the museum? Same for Gates. Busy explaining how ChatGPT is the
> best thing ever while all the money spent for “saving the world” seems to
> have led to nothing.
>
> Regards,
> Tarek Hoteit
>
> > On Apr 25, 2023, at 6:50 AM, Paul Koning via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > 
> >
> >> On Apr 25, 2023, at 9:43 AM, geneb via cctalk 
> wrote:
> >>
> >>> On Tue, 25 Apr 2023, Tom Hunter via cctalk wrote:
> >>>
> >>> Hopefully the LCM will be sold as a going concern rather than just a
> >>> firesale of the assets.
> >> AFAIK, it's a 503(c), and I suspect if they started to "fire sale"
> assets, lawsuits from folks that made significant donations would be
> inbound.
> >
> > Maybe, but what grounds would there be for a suit?  If you donate to the
> museum, the thing becomes their property, to dispose of as they see fit.
> That is, unless you have a contract that says otherwise -- and even so,
> you'd have to hope that a court would enforce a contract.  There is ample
> precedent of courts disregarding the plain English text of contracts or
> trusts to permit museums to do things prohibited by the terms of agreements
> with donors.  A recent one (name forgotten) in Pennsylvania comes to mind.
> >
> >paul
> >
> >
>

[cctalk] Re: Nuking an MFM drive with a magnet, format/servo gone?

[Adrian Godwin via cctalk]

Or ST506 ?

On Fri, Feb 3, 2023 at 5:21 PM Alexandre Souza via cctalk <
cctalk@classiccmp.org> wrote:

> I thoug the right one was st512...can you enlighten me on this subject
> Tony?
>
> Enviado do meu Tele-Movel
>
>
> > I assume by 'MFM' you mean a drive with an interface similar to the
> ST412.
> > -tony
> >
>

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Adrian Godwin via cctalk]

On Fri, Feb 3, 2023 at 4:45 PM Chuck Guzis via cctalk 
wrote:

>
> Another problem with very old core is that its physical integrity is
> often an issue.   Cores can crack, being essentially ceramics.  I'm
> reminded of the CE fishing around in the oil bath of a 7090 with what
> amounted to a magnet on a broomstick to grab loose bits of core.
>
>
True 'bit rot' !

[cctalk] Re: Chatgpt : I had a retro dream

[Adrian Godwin via cctalk]

Fortunately the hype cycle already seems to be on the down trend, as people
realise it's not an efficient way to handle natural-language questions but
is an extremely effective bullshit generator. It may get as far as
replacing politicians and estate agents as the archetypal liar, which will
hurt actual AI for years to come.


On Tue, Feb 7, 2023 at 12:25 PM emanuel stiebler via cctalk <
cctalk@classiccmp.org> wrote:

> On 2023-02-07 05:46, Cedric Amand via cctalk wrote:
> > I had a dream ; that someone makes a small telnet to chatgpt gateway
> (using azure chatgpt API possibly ?) So that we could telnet our retro
> devices to the hype of the year, and get chtgpt answers in our TRS80, PDP
> and such.
>
> I'm not sure this group is exactly about following the latest hype :)
>
> ChatGPT? Eliza on steroids ;-)
>
>

[cctalk] Re: Store with "vintage" computers and parts

[Adrian Godwin via cctalk]

On Thu, Feb 9, 2023 at 7:14 PM Eric Moore via cctalk 
wrote:

> I am very sorry to anyone I insulted. My tone was condescending. My only
> intention was sincere concern for any fellow travellers who may be reading.
>
>
Without your comment, I wouldn't have got the chuckle from Fred's :).

[cctalk] Re: Store with "vintage" computers and parts

[Adrian Godwin via cctalk]

I normally use DuckDuckGo as it's the default in Brave, the degoogled
version of Chrome that I use. It generally does what I want, but whereas
google will usually give me local (UK) results first for suppliers,
Duckduckgo will give worldwide results (which mostly means USA). You could
see Google's result as either more helpful or annoyingly tainted, but at
least it shows an instance where they're not explicitly evil. Adding 'uk'
into the search term is usually enough to prioritise local results in DDG.

I sometimes use google when I don't get a useful result : as well as the
localisation it also seems to find either different or more results. I
couldn't say whether it's got worse at that but I filter the results for
obvious ads fairly automatically.


On Fri, Feb 10, 2023 at 3:49 AM Rick Murphy via cctalk <
cctalk@classiccmp.org> wrote:

> On 2/9/2023 5:40 PM, Doug Jackson via cctalk wrote:
> > At this point I will chime in.
> >
> > 
> >
> > They clearly went to the trouble of trawling through USPS tracking
> details
> > to find something that was shipped from near their suburb to Sydney
> > Australia by somebody else and submitted it as their evidence they had
> > shipped.
>
> This is called a "brushing" attack.
>
> They sell you a high value item, then send some crappy nearly free item
> to some other address in the vicinity, and use that to "prove" to PayPal
> that you got it.
>
> The recipient has no idea WTF the item is so they discard it. Apparently
> the folks here don't understand just how far apart Australian cities can
> be.  Worked in your favor.
>
> > I went ballistic with paypal, and got a refund.
>
> It's good to hear that PP did that.
>  -Rick
>
>

[cctalk] Re: Getting floppy images to/from real floppy disks.

[Adrian Godwin via cctalk]

On Sun, May 28, 2023 at 7:18 AM Tony Duell via cctalk 
wrote:

> >
> > Tony, I don't recall what became of the AT with 486 replacement
> > processor that used to be your main home machine.  ISTR it had loads of
> > different floppy drives hung off it.  Is it still functional /
> repairable?
>
> Still works, or at least it did when I last powered it up. But no easy
> way to read USB sticks or SD cards on it.
>
> -tony
>

That sounds too useful  to give up on.
What about using a gotek drive or similar to put a USB stick on the floppy
bus, and/or one of the dos-based 3rd party IP stacks for ftp access ?

[cctalk] Re: Rainbow H7842 PSU Fault

[Adrian Godwin via cctalk]

On Tue, May 30, 2023 at 11:30 AM Christian Corti via cctalk <
cctalk@classiccmp.org> wrote:

>
> SMPUs don't like that, and don't even try a variable transformers.
>
>
In the 80s, i worked for a company making just-pre-PC 8086 machines. We
manufactured the SMPSU in-house, designed by a specialist company. I was
involved in training the technicians to repair them and built a debug rig
with the designer's advice.

This may not apply to all SMPUs but worked well for that design, which was
fairly conventional.

There was an isolation transformer followed by a variac. The procedure was
to slowly bring up the variac until the control circuit was functioning,
check the waveforms around that, and then increase the supply voltage while
watching the chopper, control and output signals. This allowed the chopper
to work at low current limited by the circuit resistance and slowly
increase with supply voltage until the control circuit backed it off (which
would happen quite quickly with no output load).

I agree that low input voltage with a loaded output will stress the supply
but done carefully as above it should be possible. I didn't use a lamp, but
the idea there is that the maximum current in the case of a short is
limited to lamp current rather than fuse current. I wouldn't do this with
much of a load, but it's more likely to kill the chopper due to dissipation
rather than peak current since it's rated to chop the full input DC rail
into the transformer. Abuse might cause higher frequency cycling or longer
on-time but shouldn't increase peak current.
I'm happy to learn if I'm missing another mechanism.

[cctalk] Re: Source for NEW (unused) punch tape

[Adrian Godwin via cctalk]

On Thu, Jun 8, 2023 at 6:01 PM Paul Koning  wrote:

> I wonder if mylar tape for punching could be found, or made.  That was
> seen occasionally, for applications where a tape needed to be read many
> times.  An OS binary tape might want that.  I also remember seeing it on a
> machine in my father's lab, where it contained correction factors for a
> piece of precision machinery.
>

I've seen mylar tape used in a tiny loop where it controlled the movements
of a printer platen. I don't recall now whether it was used for horizontal
or vertical space - my recollection was the latter but it was a long time
ago.

I don't know why it wasn't controlled by ASCII - a good bit of the
character set is dedicated to print head control. I think a different tape
had to be installed to match the program that was being run. The machine
was used for accountancy in about 1975, It was a bit like a large LA120
(but included the calculating part) and made by the french Logabax company.

I worked in a manufacturing plant around 1985 where the (new)
pick-and-place machine was controlled by a paper tape. The tape was punched
on an ASR33 or similar. It seemed like an obsolete solution even though
only just installed. I bought a very nice surplus Facit tape punch from a
classified ad in Wireless World, built a serial to parallel interface and
allowed the machine programmer to create the source on a word processor
(which was our manufactured product) instead.

[cctalk] Re: Source for NEW (unused) punch tape

[Adrian Godwin via cctalk]

A slitter is a wide paper feed system with sharp-edged pulleys over which
it passes. There are quite a few videos of this on youtube, it's
surprisingly well documented. Because slitter manufacturers are selling to
mom-and-pop outfits.

I think the tape is supplied unpunched and the tape punch makes both feed
holes and data holes. I could be wrong.


On Thu, Jun 8, 2023 at 5:10 PM Chuck Guzis via cctalk 
wrote:

> On 6/8/23 08:52, Adrian Godwin via cctalk wrote:
> > I think paper-slitters are pretty common. That is to say, if you go to
> > anyone manufacturing adding machine rolls they will have the capability
> to
> > make custom widths in rather small job lots. It's an industry comparable
> > with printing (and often combined, for when till rolls with custom
> printing
> > is desired). So it may be that although paper tape is no longer available
> > from computer stationary suppliers, it can very easily be made in quite
> > small MOQs.
>
> How does one, using modern equipment, both slit and perforate (feed
> holes) blank tape?  Color me curious.
>
> --Chuck
>

[cctalk] Re: Source for NEW (unused) punch tape

[Adrian Godwin via cctalk]

This wasn't a large IBM lineprinter and I'm pretty sure it was 1" tape, but
it may well have been inspired by those machines.  It would likely have
been used with custom fanfold paper for invoices, cheques etc. - certainly
the same sort of customer-specific those machines dealt with, but for the
small office. A predecessor to the PC.

On Thu, Jun 8, 2023 at 7:13 PM Paul Koning  wrote:

>
>
> > On Jun 8, 2023, at 1:18 PM, Adrian Godwin  wrote:
> >
> > ...
> > I've seen mylar tape used in a tiny loop where it controlled the
> movements of a printer platen. I don't recall now whether it was used for
> horizontal or vertical space - my recollection was the latter but it was a
> long time ago.
> >
> > I don't know why it wasn't controlled by ASCII - a good bit of the
> character set is dedicated to print head control. I think a different tape
> had to be installed to match the program that was being run. The machine
> was used for accountancy in about 1975, It was a bit like a large LA120
> (but included the calculating part) and made by the french Logabax company.
>
> Many line printers used a "VFD" tape (vertical format definition?) which
> is a 12-channel tape with one row per line on the paper.  The idea was that
> you could tell the printer "skip to channel N" and it would advance the
> paper until a hole in that channel was seen.  By convention, channel 1
> marks the top of the page, and in fact typically that position was punched
> all the way across so a skip to an "unused" channel would not produce
> runaway paper.  Channels other than 1 would be used for custom forms, where
> it would save time to skip across part of the form rather than advancing
> line by line to the desired spot.
>
> If you only ever used regular size paper this stuff wouldn't be obvious,
> but an operator who had to handle other forms, like checks or label stock
> or anything else that wasn't just plain 60/66 line pages, would have to
> change the paper along with the matching format tape.  Some printers had
> small local memories that could be downloaded with the form definition tape
> data, avoiding the need for the operator to switch the tape manually.
>
> paul
>
>

[cctalk] Re: Source for NEW (unused) punch tape

[Adrian Godwin via cctalk]

I think paper-slitters are pretty common. That is to say, if you go to
anyone manufacturing adding machine rolls they will have the capability to
make custom widths in rather small job lots. It's an industry comparable
with printing (and often combined, for when till rolls with custom printing
is desired). So it may be that although paper tape is no longer available
from computer stationary suppliers, it can very easily be made in quite
small MOQs.

I don't know this for sure and I haven't called anyone, it's just a
recollection from when my father ran a stationary business that till rolls
aren't always high-volume products from till manufacturers but low-volume
customised supplies  made very flexibly.


On Thu, Jun 8, 2023 at 4:43 PM David Gesswein via cctalk <
cctalk@classiccmp.org> wrote:

> Someone did a paper-slitter in this thread
>
>
> https://forum.vcfed.org/index.php?threads/paper-tape-punch-service-and-request.1242805/page-2#post-1319033
>
> On Mon, Jun 05, 2023 at 06:19:26PM -, robot...@gmail.com wrote:
> > For various reasons (including, but not limited to, insanity and
> obsessiveness*) I am building a diode laser based tape punch. It's not
> specifically for a classic comp, but I'd like to stick with standard format
> so that it'd be useful for making custom tapes for members in the future. I
> will probably need to make dozens of tapes so using actual, vintage rolls
> is out of the question. Does anyone know if 1" tape is used for anything
> else and where I might find some new? Otherwise I may have to add
> paper-slitter to my project list and make my own.
> >
> >
> >
> >
> > *I've had the idea of a lost-media ARG stuck in my head for years.
> >
> > --
>

[cctalk] Re: Source for NEW (unused) punch tape

[Adrian Godwin via cctalk]

The perforations might be a problem but could this work ?
https://www.ebay.co.uk/itm/324481731229


On Mon, Jun 5, 2023 at 8:58 PM Wayne S via cctalk 
wrote:

> There is this for ideas…
>
> https://www.instructables.com/DIY-Paper-TapePunch-Card-Maker-and-Reader/
>
>
> Sent from my iPhone
>
> On Jun 5, 2023, at 12:29, Anders Nelson via cctalk 
> wrote:
>
> This is an awesome idea, please make it. How great would it be to load a
> receipt-paper roll (made of heavier stock of course), lase the holes and
> pass the paper over a vacuum slot to suck the chads.
>
> I was trying to come up with a mostly 3d-printable, cam-driven punch myself
> but of course it will never get done.
>
> Happy to provide any hardware/embedded help if wanted!
>
> --
> Anders Nelson
>
>
> On Mon, Jun 5, 2023 at 2:19 PM Robotguy via cctalk 
> wrote:
>
> For various reasons (including, but not limited to, insanity and
> obsessiveness*) I am building a diode laser based tape punch. It's not
> specifically for a classic comp, but I'd like to stick with standard format
> so that it'd be useful for making custom tapes for members in the future. I
> will probably need to make dozens of tapes so using actual, vintage rolls
> is out of the question. Does anyone know if 1" tape is used for anything
> else and where I might find some new? Otherwise I may have to add
> paper-slitter to my project list and make my own.
>
>
>
>
> *I've had the idea of a lost-media ARG stuck in my head for years.
>
>

[cctalk] Re: Greaseweazle part 2

[Adrian Godwin via cctalk]

On Sun, Jun 11, 2023 at 9:29 AM Tony Duell via cctalk 
wrote:

> However I am not sure if I'll be able to use it. There is one very
> important thing missing : DOCUMENTATION. The 'wikii' on github is
> ridiculously incomplete. There is no user manual or man pages. The
> software source in python (a language I've never used) has very few
> comments and is not clear at all.
>
> It's not clear to me exactly what all the options are for, and when to use
> them.
>
> -tony
>

I also got one ion the hope I'd be able to read a 1.44MB dos floppy that
may or may not have some useful software on it.
It installed and ran without issue on Linux but, like Tony, I'm finding the
documentation a bit short. And I don't know much python either though I do
find it fairly readable.

I have tried the examples that do exist and they work as described. It's
not clear though yet how to proceed though in the simplest case I think it
has provided me with a 1.44MB image of a test floppy. Using it for non-DOS
floppies may be more difficult but the main reason I'm unsure is that it's
fairly quiet about what it does and I don't know yet how much recovery work
it's done unbidden. I do believe the greaseweazle firmware includes some of
the retry mechanism and may 'just work'. Note that the test floppy I'm
using is easily readable.

However, while I was waiting for the board, I looked around for software
and as well as that recommended by the designer I also found some called
fluxengine. This was written for a different adapter - actually a Cyprus
dev board connected directly to a floppy socket, not a custom board, but it
supports the greaseweazle adapter and only lose part of the functionality.
I haven't investigated the documentation on that yet but it's very well
presented and I have hopes that I wil be able to use it too. I'd recommend
looking at it - it was very little trouble to get working. I didn't try it
on Windows but it has support for that.
https://github.com/davidgiven/fluxengine

I think there were a couple of recommendations for greaseweazle here so I
guess someone's found it useful before. I'm interested in any hints - if
you send any to tony please cc me.

Although Tony seems to have resolved his Windows problems, it did occur to
me that this could be paired with a raspberry pi or clone to make a
self-contained device with little cost or effort.

-adrian

[cctalk] Re: Greaseweazle part 2

[Adrian Godwin via cctalk]

Further on the greaseweazle docs - there is a forum at
https://github.com/keirf/greaseweazle/discussions which seems quite lively
and may be the right place to start.

On Sun, Jun 11, 2023 at 9:56 AM Adrian Godwin  wrote:

> On Sun, Jun 11, 2023 at 9:29 AM Tony Duell via cctalk <
> cctalk@classiccmp.org> wrote:
>
>> However I am not sure if I'll be able to use it. There is one very
>> important thing missing : DOCUMENTATION. The 'wikii' on github is
>> ridiculously incomplete. There is no user manual or man pages. The
>> software source in python (a language I've never used) has very few
>> comments and is not clear at all.
>>
>> It's not clear to me exactly what all the options are for, and when to
>> use them.
>>
>> -tony
>>
>
> I also got one ion the hope I'd be able to read a 1.44MB dos floppy that
> may or may not have some useful software on it.
> It installed and ran without issue on Linux but, like Tony, I'm finding
> the documentation a bit short. And I don't know much python either though I
> do find it fairly readable.
>
> I have tried the examples that do exist and they work as described. It's
> not clear though yet how to proceed though in the simplest case I think it
> has provided me with a 1.44MB image of a test floppy. Using it for non-DOS
> floppies may be more difficult but the main reason I'm unsure is that it's
> fairly quiet about what it does and I don't know yet how much recovery work
> it's done unbidden. I do believe the greaseweazle firmware includes some of
> the retry mechanism and may 'just work'. Note that the test floppy I'm
> using is easily readable.
>
> However, while I was waiting for the board, I looked around for software
> and as well as that recommended by the designer I also found some called
> fluxengine. This was written for a different adapter - actually a Cyprus
> dev board connected directly to a floppy socket, not a custom board, but it
> supports the greaseweazle adapter and only lose part of the functionality.
> I haven't investigated the documentation on that yet but it's very well
> presented and I have hopes that I wil be able to use it too. I'd recommend
> looking at it - it was very little trouble to get working. I didn't try it
> on Windows but it has support for that.
> https://github.com/davidgiven/fluxengine
>
> I think there were a couple of recommendations for greaseweazle here so I
> guess someone's found it useful before. I'm interested in any hints - if
> you send any to tony please cc me.
>
> Although Tony seems to have resolved his Windows problems, it did occur to
> me that this could be paired with a raspberry pi or clone to make a
> self-contained device with little cost or effort.
>
> -adrian
>

[cctalk] Re: Greaseweazle part 2

[Adrian Godwin via cctalk]

Sorry to drip-feed this, but
https://wiki.archiveteam.org/index.php/Rescuing_Floppy_Disks is a useful
source on comparing various methods. It's clear that this type of interface
has particularly strong support on Apple due to their previous use of
non-IBM formats, and Amiga is also quite common (I think that's where
greaseweazle started).

[cctalk] Re: Greaseweazle part 2

[Adrian Godwin via cctalk]

I would have liked to find that comparison site earlier. However I think
I'd still have gone for greaseweazle.

On Sun, 11 Jun 2023, 09:29 Tony Duell via cctalk, 
wrote:

> Well, I've got the Greaseweazle software to run, but I don't know why,
> which is hardly encouraging.
>
> Installing various Windows updates, downloading .dlls, and puting the
> latter in various directories changed the error messages but it never
> actually worked. But downloading the latest Greaseweazle software did,
> it ran first time. So no idea what I was doing wrong (maybe 32 bit
> .vs. 64 bit Windows applications?)
>
> I can now get the list of commands when I run gw.exe. And can get help
> on them using the -h option. I've not tried connecting a drive yet,
> but the software can find and talk to the board (the green 'activity'
> LED turns on). For example 'gw rpm' which is used to check the drive
> speed by timing the index pulses times out and gives a 'no index'
> error which seems entrely reasonable.
>
> However I am not sure if I'll be able to use it. There is one very
> important thing missing : DOCUMENTATION. The 'wikii' on github is
> ridiculously incomplete. There is no user manual or man pages. The
> software source in python (a language I've never used) has very few
> comments and is not clear at all.
>
> It's not clear to me exactly what all the options are for, and when to use
> them.
>
> -tony
>

[cctalk] Re: Getting floppy images to/from real floppy disks.

[Adrian Godwin via cctalk]

Tony,

An instrument slightly more to your taste than a PC might a 16500b logic
analyser. Perhaps you've already got one. I believe these can work with
both LIF and MSDOS floppies and uses an IDE HDD (which can painlessly be
replaced with CF card) in DOS format internally. I don't know if it will
handle other than 3.5" formats but it's quite possible that the support for
those formats is generic and it might work, given an appropriately mangled
hardware interface.

-adrian

[cctalk] Re: 50 pins in three rows

[Adrian Godwin via cctalk]

On Sat, Aug 12, 2023 at 7:12 PM Chuck Guzis via cctalk <
cctalk@classiccmp.org> wrote:

>
> I wonder if these are from a group buy not long ago, where someone got a
> manufacturer to gin up a lot of them (minimum order was something like
> 1,000).
>
>
They were quite common at one point. I hacked the first one I needed but
later had no problem buying them.  This was before eBay but typically they
were available at computer fairs, which could be found in every town on a
sunday selling floppy discs, cables, Linux CD sets and possibly dodgy
software.

[cctalk] Re: Did Bill Gates Really Say That?

[Adrian Godwin via cctalk]

I think what he meant was ' no application needs more than 640k - the rest
is for the operating system'


On Fri, 16 Jun 2023, 08:43 Steve Lewis via cctalk, 
wrote:

> I don't think Gates ever actually said this - but that's just based on my
> own examination into this from a few years back.
>
> But, over the years I've done some thread programming, and I was once
> solving a problem by loading a lot of data into main memory (like 8-16GB of
> data to process as one huge chunk, on a system that only had 32GB total).
>
> A while later, I had a thought that actually maybe this quote has some
> merit.  Maybe not the specific amount (of 640KB) - but the general notion
> that there is rarely a reason for a single application to consume the
> entirety of main memory.It may be better, especially with threads or
> multi-core, to work a problem in smaller chunks -- specifically, to work a
> problem in chunks smaller than the CPU cache.   And in fact, I found a huge
> jump in my programs performance when I kept the buffers exactly 1 byte less
> than the CPU cache (at the time that was 1MB) - as soon as I went 1 byte
> over, I noticed a huge (~3X) hit in performance.   Now that's just a single
> data point, and the old advise of "never optimize your program for
> performance too early" is probably still good.  And especially most shops
> won't spend the time/resources to cache optimize their builds - I suspect
> some games do at startup, they maybe profile what your L3 cache size.
>
>
> Anyhow, years ago I recall coming across a quote or an article where Gates
> stated the IBM PC (or maybe the 8088 cpu itself) was designed or intended
> to only "last" about 10 years.  Not that the system components itself would
> only last that long, but as it being a "useful" system.   In that context,
> maybe he was right (if he had said it) - 640K was maybe "enough for anyone"
> for the remainder of the 1980s.   I recall starting with 384KB (thinking
> anything past 128KB was "huge") and doing upgrades in the late 1980s to get
> to 640KB, and not getting into extended/expanded memory until the early
> 90s.  This would be for "typical" household applications (taxes, small
> business, word processing) - obviously image processing (CAD, movie
> rendering, etc.) or multi-user servers do need more memory.
>
> I also recall that it was Intel that requested to keep it to 10 segments of
> 64KB (640KB), not really a Microsoft or MS-DOS doing.  i.e. aspects beyond
> Microsoft wanted to reserve the "upper memory" for other stuff (video
> memory). You have 16 segments, how many to hold in reserve?  Someone
> chose 6.  Quick and Dirty OS indeed.
>
>
>
> On Tue, Jun 13, 2023 at 11:47 PM Ali via cctalk 
> wrote:
>
> > So I had always heard the quote "640KB is enough memory" being attributed
> > to
> > Bill Gates. However, recently I was watching Dave Plummer on YT and he
> said
> > that it is not true:
> >
> > https://youtu.be/bikbJPI-7Kg?t=372
> >
> > And apparently the man himself has denied it as well but it just will not
> > go
> > away...
> >
> > https://abcnews.go.com/Technology/PCWorld/story?id=5214635
> >
> > So I guess like the napkin/disk story and the DR/IBM story this is
> another
> > one of those vintage myths and folk lore with no real basis in
> reality
> >
> > -Ali
> >
> >
> >
> >
>

[cctalk] Re: IBM 360

[Adrian Godwin via cctalk]

And the 'tarpit' book is 50, dated by the preface.

On Wed, Apr 10, 2024 at 6:22 AM Chuck Guzis via cctalk <
cctalk@classiccmp.org> wrote:

> On 4/9/24 22:03, ben via cctalk wrote:
> > On 2024-04-09 8:53 p.m., Murray McCullough via cctalk wrote:
> >> I had not realized the IBM 360 was 60 yrs. old this month. I worked on
> >> such
> >> a computer in the late 60s in Toronto. What one could do with 8 Kbytes
> of
> >> ram was remarkable!
> >>
> >> Happy computing
> >>
> >> Murray 
> > Real time sharing, not a 16K PDP 8?
>
> What model of a 360?  8K sounds a lot like a Model 20, which the purists
> may not consider to be a "real" member of the family.
>
>  --Chuck
>
>
>

[cctalk] Re: Bomar 901b My wife found in my stuff. Is this as scarce at it seems?s,?

[Adrian Godwin via cctalk]

On Tue, Apr 16, 2024 at 10:21 PM Fred Cisin via cctalk <
cctalk@classiccmp.org> wrote:

>
> Although the HP-35 was the first "pocket calculator" from HP, it was not
> the first handheld calculator.
>
>
I think it was the first *scientific* pocket calculator though.

[cctalk] Re: Versatec Electrostatic Printers (was :Re: Re: Odd IBM mass storage systems)

[Adrian Godwin via cctalk]

It wasn't just Versatec plotters that used this mixture - standard office
photocopiers also had clay-coated paper and liquid toner. I don't know what
allowed the change to plain-paper copiers (which use an intermediate
photosensitive drum, like a laser printer) but it was probably the expiry
of a patent, maybe Xerox's.


On Sun, Apr 14, 2024 at 8:02 AM Paul Anderson via cctalk <
cctalk@classiccmp.org> wrote:

> I have a Versatec interface here somewhere, but I don't remember if it is
> for an 8 or 11.
>
> Paul
>
> On Sun, Apr 14, 2024 at 1:40 AM Tony Duell via cctalk <
> cctalk@classiccmp.org>
> wrote:
>
> > On Sat, Apr 13, 2024 at 10:48 PM Jon Elson via cctalk
> >  wrote:
> >
> > > Yes, there were a number of Versatec models for different
> > > paper sizes and pixel density.
> >
> > Does anyone else have one in their collection?
> >
> > I have an ICL-badged V80 which has a GPIB interface to link it to a
> > PERQ. I also have the schematics, etc for the plain V80 but nothing on
> > the GPIB interface (ether user or service data). IIRC the V80 is based
> > round a Texas 16-bit microprocessor with some AM2900-series sequencers
> > and ROMs to control the electrode timing.
> >
> > As Jon said in the bit I deleted, there's a 'nib electrode' under the
> > paper and a segmented backing electrode above it. The charge image is
> > built up on the paper, then the toner is flowed over it and the carbon
> > (I assume) particles adhere to the charged bits. No drying heater in
> > mine.
> >
> > -tony
> >
>

[cctalk] Re: Bomar 901b My wife found in my stuff. Is this as scarce at it seems?s,?

[Adrian Godwin via cctalk]

901B is the first pocket calculator I remember - I don't know if there were
earlier ones.
I don't think they're exactly rare but later ones such as MX10 are
certainly easier to find. They're often in the same case as a 901B but with
slightly enhanced functionality such as 10 digits. % key etc.


On Tue, Apr 16, 2024 at 12:31 PM ED SHARPE via cctalk 
wrote:

> Yes. Cell phone horrible typing
> The Consumer Electronics Hall of Fame: Bowmar 901B
> Ok can not find b pricevonly c and d
>
> Sent from AOL on Android
>
>   On Tue, Apr 16, 2024 at 3:41 AM, Will Cooke via cctalk<
> cctalk@classiccmp.org> wrote:   I think he means Bowmar
> https://spectrum.ieee.org/the-consumer-electronics-hall-of-fame-bowmar-901b
>
>
>
> > On 04/16/2024 5:34 AM CDT ED SHARPE via cctalk 
> wrote:
> >
> >
> > No bomar brand
> >
> > Sent from AOL on Android
> >
> > On Mon, Apr 15, 2024 at 7:15 PM, Wayne S
> wrote: Bomar as in the Bomber Aircraft?
> >
> > Sent from my iPhone
> >
> > > On Apr 15, 2024, at 19:04, ED SHARPE via cctalk 
> wrote:
> > >
> > > Bomar 901b My wife found in my stuff. Is this as scarce at it seems?s,?
> > >
> > >
> > > Sent from AOL on Android
>
> Grownups never understand anything by themselves and it is tiresome for
> children to be always and forever explaining things to them,
>
> Antoine de Saint-Exupery in The Little Prince
>
>

[cctalk] Re: FWIW CD & DVD demagnetization [was: Double Density 3.5" Floppy Disks]

[Adrian Godwin via cctalk]

Best to have an atmosphere of dry nitrogen, too.
Breathing that may take some practice.

On Thu, May 9, 2024 at 11:19 AM Antonio Carlini via cctalk <
cctalk@classiccmp.org> wrote:

> On 09/05/2024 03:41, D. Resor via cctalk wrote:
> > Next they'll want silver oxygen free plated plumbing and sewage pipes in
> their homes.  Silver plated toilet seats?
> >
> > Walls insulated with Palladium coated corn silk threads?
> >
> > Seems the subject has really gone astray? Lions, Tigers and Bears oh
> my! )
> >
> > Don Resor
> >
> > -Original Message-
> > From: Sellam Abraham via cctalk 
> > Sent: Wednesday, May 08, 2024 7:01 PM
> > To: General Discussion: On-Topic and Off-Topic Posts <
> cctalk@classiccmp.org>
> > Cc: Sellam Abraham 
> > Subject: [cctalk] Re: FWIW CD & DVD demagnitizitation [was: Double
> Density 3.5" Floppy Disks]
> >
> > Why stop there?  A truly dedicated audiophile would run new pure silver
> electrical wire through the walls directly to the breaker box.
> >
> > Then you gotta upgrade to the breaker box that was disinfected from
> transient spirits through an exorcism, and then special 24K solid
> gold-contact breakers in inert nylon housings.
>
> Surely you have to get the cables upgraded all the way back to the
> original generator? Then you have secondary effects, for example, with
> hydro power, the purity of the water makes a *huge* difference.
>
>
> I also think it's just as important to have your ears, and the gap
> between them syringed too.
>
>
> Antonio
>
>
>
> --
> Antonio Carlini
> anto...@acarlini.com
>
>

[cctalk] Re: 5,34 Petaflop System Cheyenne

[Adrian Godwin via cctalk]

Fairly sure you could find something to run Doom that uses less than 1.7MW

(from
https://arstechnica.com/information-technology/2024/04/us-government-auctions-5-34-petaflop-cheyenne-supercomputer/
)


On Fri, May 3, 2024 at 3:23 PM Ali via cctalk  wrote:

>
> >Just 7 year old and no longer in service.>Anyone with some space in the
> basement ?But will it run Doom?

[cctalk] Re: BASIC

[Adrian Godwin via cctalk]

I learnt to program at uni on prompt-48, an 8048 development system.
Hand-coded assembly, entered in hex and saved to EPROM. Later I moved to
z80 with an assembler hosted on a pdp 11/34. Later still I had to do a
customer project specified to be written in BASIC on an apple II (no square
brackets on this phone keyboard!). I learned much respect for people who
had to code in that crummy inflexible language :). Briefly learned some
pascal then with much relief discovered C. Not really found anything better
for the things I like to work on.

On Thu, 2 May 2024, 07:08 CAREY SCHUG via cctalk, 
wrote:

> I recall IITRAN for the IBM 7044, and am i correct that there was an
> IITRAN for the Univac 1108, which was significantly different?
>
> --Carey
>
> > On 05/01/2024 6:37 PM CDT Sellam Abraham via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> >
> > On Wed, May 1, 2024 at 4:36 PM Chuck Guzis via cctalk <
> cctalk@classiccmp.org>
> > wrote:
> >
> > > To be sure, BASIC was hardly unique in terms of the 1960s interactive
> > > programming languages.  We had JOSS, PILOT, IITRAN and a host of
> others,
> > > based on FORTRAN-ish syntax. not to forget APL, which was a thing
> apart.
> > >
> > > --Chuck
> > >
> >
> > And where are all those other languages today?
> >
> > I rest my case.
> >
> > ;)
> >
> > Sellam
>

[cctalk] Re: CP/M

[Adrian Godwin via cctalk]

There was also Concurrent CP/M (possibly only a /86 variant).

On Sat, May 4, 2024 at 2:02 AM Bill Degnan via cctalk 
wrote:

> Herb Johnson has some good info on the history of cp/m here
> https://www.retrotechnology.com/#dri
> Bill
>
> On Fri, May 3, 2024, 8:23 PM Murray McCullough via cctalk <
> cctalk@classiccmp.org> wrote:
>
> > I came across an article that said CP/M came out in April 1974. I
> remember
> > using this OS in the microcomputer world in the late 70’s; early 80’s. It
> > came from PL/M, (Programming Language for Microcomputers) later renamed
> > CP/M(Control Program for Microcomputers). I’m not sure what its legacy is
> > though as far as I can recall it was wrapped up in litigation for quite
> > some time. It was used in the 8-bit world but not sure what it's role was
> > in the early PC world!
> >
> > Happy computing,
> >
> > Murray 
> >
>

[cctalk] Re: DEC Processor Books

[Adrian Godwin via cctalk]

HP at least sometimes used staff.
I'm recalling 'Mr Fancypants' identified and contacted by Curious Marc in
his series on the 9825 repairs.

On Sun, Mar 17, 2024 at 3:11 PM Dennis Boone via cctalk <
cctalk@classiccmp.org> wrote:

>  > I have often wondered about the people we find in the various DEC
>  > Processor (and other) books.  Were they models in staged
>  > photo-sessions or were these candid shots from DEC facilities and if
>  > so, can anyone identify who they might be.
>
> Someone asked this about the covers of the old Prime manuals.  The FAQ
> has a list of identifications, earlier ones were in-house staff, later
> stock photos were used.  I'd be astonished if any of the photos were
> candid.
>
> I imagine DEC did much the same.
>
> De
>

[cctalk] Re: typical IC kits on Amazon and elsewhere

[Adrian Godwin via cctalk]

Has anyone had problems with LCSC ?
They can be a lot cheaper than mouser or digikey but I tend to trust them
more than Aliexpress and ebay.

On Sun, Mar 31, 2024 at 7:18 AM Don R via cctalk 
wrote:

> My problem with DigiKey is tacking on the additional “tariff” charge on
> invoices.  Granted it’s not an extreme amount, but still…
>
> I contacted Mouser about imposing additional tariff charges, and was told
> a resounding no.
>
> Thanks to our past president for increasing the cost of doing business,
> and thanks to our current president for not caring enough to roll it back.
>
> Getting off soap box. :o)
>
> Don Resor
>
> Sent from someone's iPhone
>
> > On Mar 30, 2024, at 8:48 PM, Tom Hunter via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > I am very happy to buy from Amazon and Digikey even if sometimes they
> are a
> > little more expensive. I want them to be around for the long term, so I
> > support them as much as possible. Their range is amazing.
> >
> >> On Sun, 31 Mar 2024, 10:53 am Glen Slick via cctalk, <
> cctalk@classiccmp.org>
> >> wrote:
> >>
> >>> On Sat, Mar 30, 2024 at 5:11 PM Jonathan Chapman via cctalk
> >>>  wrote:
> >>>
>  Standard TTL 74XXX is drying up rather quickly. Futurlec still has
> some
>  TTL but 7404s are all gone. Even LS is hard to find.
> >>>
> >>> Ours comes from Mouser, between two part #s they have over 7,000
> 74LS04s
> >> in DIP packaging in stock. Didn't check ACT, HCT, or ALS. I don't think
> >> we've had a 7400 series part that we couldn't just order off Mouser in
> >> recent history, and we're usually buying QTY 100.
> >>>
> >>
> >> You can also buy parts direct from TI, for example they currently show
> >> around around 3000 SN74LS04N parts in stock.
> >>
> >> https://www.ti.com/product/SN74LS04/part-details/SN74LS04N
> >>
> >> The prices for that part match the current Mouser prices of $0.674
> >> each, or $0.519 each if you buy at least 4 tubes of 25 parts.
> >>
> >> I've bought some tubes of 74LS parts direct from TI in the last year.
> >>
> >
>
>

[cctalk] Re: DEC Processor Books

[Adrian Godwin via cctalk]

It's well known that a necktie restricts the supply of blood to the brain.

[cctalk] Re: oscilloscopes

[Adrian Godwin via cctalk]

On Thu, Apr 4, 2024 at 8:36 PM Paul Koning via cctalk 
wrote:

> >
> >> https://scopeclock.com/ 
> > Technically, the scopeClock is generating neither curves nor vectors,
> it's generating pixels in an XY display - it's just that they’re of fine
> enough resolution and fast enough that they’re seen as a smooth-enough
> curve on the CRT.
> >
>
>
That's disappointing. There was such a clock, and I thought I'd found it
since it described using circle generators - but was surprised to find it
used a teensy.
Does anyone know which clock used analog circuits to form the characters ?

[cctalk] Re: C. Gordon Bell, Creator of a Personal Computer Prototype, Dies at 89

[Adrian Godwin via cctalk]

At least it's a better title than 'The centre for computing history'
(Cambridge, UK).


On Wed, May 22, 2024 at 9:39 PM Sellam Abraham via cctalk <
cctalk@classiccmp.org> wrote:

> On Wed, May 22, 2024 at 1:15 PM John Foust  wrote:
>
> > At 01:32 PM 5/22/2024, Sellam Abraham via cctalk wrote:
> > >His and his wife
> > >Gwen's (god rest her soul as well) personal collecting and the museum at
> > >DEC was the basis for the Boston Computer Museum, which effectively went
> > >west and became the Computer History Museum.
> >
> > He was quite sensitive about this.  I made the same mistake, referring
> > to it as the "Boston Computer Museum."  He told me:
> >
> > "Let me be clear The Computer Museum (TCM) was NEVER called the
> > Boston Computer Museum...  Boston was a temporary home when computing
> > passed through New England, but the city itself gave nothing to it.
> > ...  As a former collector, founder, and board member of the
> > Digital Computer Museum > The Computer Museum >> current Computer History
> > Museum
> > (a name I deplore and that exists only because of the way the Museum left
> > Boston)
> > I have always been a strong advocate of getting as many artifacts into as
> > many
> > hands as possible, and this includes selling museum artifacts when
> > appropriate.
> > In essence a whole industry of museums and collectors is essential."
> >
> > - John
> >
>
> I appreciate the clarification.
>
> I agree that it's a shame that the CHM couldn't be called TCM.  "Computer
> History Museum" is a fairly awkward name.
>
> Sellam
>

[cctalk] Re: NTSC TV demodulator

[Adrian Godwin via cctalk]

I've also had TVs with modular RF inputs. One was a huge plasma wall TV and
the other a tiny cheap caravan TV but both had locations for an RF input
card which I assumed could be replaced by cards to suit local national TV
standards. These have no visible controls and, like the PC TV cards,
probably have an I2C tuner module. The linux TV application xawtv has code
for controlling these.

A similar device was used with BBC and Archimedes computers to receive the
UK teletext service - it tuned to the TV services and extracted data that
was broadcast in the vertical blanking interval.


On Mon, May 20, 2024 at 11:13 AM Adrian Godwin  wrote:

> At one time I had a few Bt848 based PCI TV tuner cards for a PC - Hauppage
> was a big player but there were others. Some were  composite video in, some
> also had a TV tuner section.
>
> I tried one as a video converter for PAL composite out from some home
> micro - possibly a Jupiter Ace. It wasn't that great, to be honest and
> doubtless the RF input is even worse but you don't really expect a great
> deal from an RF output in terms of video quality. If you can find one (most
> have been replaced by DVB-T cards : do they also accept analogue TV signals
> ?) they should be almost free.
>
>
>
> On Mon, May 20, 2024 at 10:03 AM Tony Duell via cctalk <
> cctalk@classiccmp.org> wrote:
>
>> On Sun, May 19, 2024 at 1:08 PM Will Cooke via cctalk
>>  wrote:
>>
>> > Does anyone know of a small TV tuner that tunes old analog TV channels
>> (US NTSC) and outputs composite or VGA or HDMI signals? I've looked around
>> a bit but haven't found anything. It's relatively easy to build one, but I
>> would prefer a pre-built solution.  And I'm sure others have run into this
>> same problem.
>>
>> Not for NTSC video, but for the UK UHF analogue TV...
>>
>> About 30 years ago we had a hobbyist electronics shop chain called
>> Maplin, who produced and sold their own range of kits, many of them
>> very good. When NICAM stereo TV sound was introduced in the UK, they
>> produced a kit to decode the NICAM signal to audio. In fact it was a
>> total of 3 kits -- the NICAM decoder board, a TV tuner/IF strip to
>> feed it (if you didn't want to try to tap off the NICAM subcarrier
>> from your existing TV 's tuner), and the case/connectors/tuner channel
>> memory/etc..
>>
>> I built the entire system for my parents who had a VCR [1] that could
>> record stereo sound from line-level inputs but which pre-dated NICAM.
>>
>> I then realised that the tuner/IF board on its own, with a multi-turn
>> pot added for tuning (rather than the remote control/memory control IC
>> used in the full unit) would be ideal for turning the RF output of UK
>> home computers into composite video. So I built a second tuner board
>> for that. Still have it, still use it.
>>
>> -tony
>>
>

[cctalk] Re: NTSC TV demodulator

[Adrian Godwin via cctalk]

At one time I had a few Bt848 based PCI TV tuner cards for a PC - Hauppage
was a big player but there were others. Some were  composite video in, some
also had a TV tuner section.

I tried one as a video converter for PAL composite out from some home micro
- possibly a Jupiter Ace. It wasn't that great, to be honest and doubtless
the RF input is even worse but you don't really expect a great deal from an
RF output in terms of video quality. If you can find one (most have been
replaced by DVB-T cards : do they also accept analogue TV signals ?) they
should be almost free.



On Mon, May 20, 2024 at 10:03 AM Tony Duell via cctalk <
cctalk@classiccmp.org> wrote:

> On Sun, May 19, 2024 at 1:08 PM Will Cooke via cctalk
>  wrote:
>
> > Does anyone know of a small TV tuner that tunes old analog TV channels
> (US NTSC) and outputs composite or VGA or HDMI signals? I've looked around
> a bit but haven't found anything. It's relatively easy to build one, but I
> would prefer a pre-built solution.  And I'm sure others have run into this
> same problem.
>
> Not for NTSC video, but for the UK UHF analogue TV...
>
> About 30 years ago we had a hobbyist electronics shop chain called
> Maplin, who produced and sold their own range of kits, many of them
> very good. When NICAM stereo TV sound was introduced in the UK, they
> produced a kit to decode the NICAM signal to audio. In fact it was a
> total of 3 kits -- the NICAM decoder board, a TV tuner/IF strip to
> feed it (if you didn't want to try to tap off the NICAM subcarrier
> from your existing TV 's tuner), and the case/connectors/tuner channel
> memory/etc..
>
> I built the entire system for my parents who had a VCR [1] that could
> record stereo sound from line-level inputs but which pre-dated NICAM.
>
> I then realised that the tuner/IF board on its own, with a multi-turn
> pot added for tuning (rather than the remote control/memory control IC
> used in the full unit) would be ideal for turning the RF output of UK
> home computers into composite video. So I built a second tuner board
> for that. Still have it, still use it.
>
> -tony
>

[cctalk] Re: interlace [was: NTSC TV demodulator ]

[Adrian Godwin via cctalk]

I remember the VT100 interlace setting. Yes, it changed the signal
generated. I don't know if it also changed the characteristics of the
monitor but I would think not.

It gave slightly higher resolution (the expectation would be double but the
tube didn't have focus that good) at the cost of a horrible juddering
display. I don't remember it being there on the later VT220.


On Mon, May 20, 2024 at 7:43 PM Will Cooke via cctalk 
wrote:

>
>
> > On 05/20/2024 12:06 PM CDT CAREY SCHUG via cctalk 
> wrote:
> >
>
> >
> > so, just curious. how do digital TVs (and monitors) work? I presume the
> dots are a rectangle, not sloping down to the right, no half a line at the
> top and bottom. Do they just assume the brain can't tell that (for the
> converted old analog tv signal) the image therefor slopes UP very slightly
> to the right from what it "should" be? and the top line is blank on the
> left side because that is the interlace frame?
> >
> > --Carey
> >
>
> Well, the slope is VERY slight.  Approximately 1/500 of the picture
> height.Probably impossible to detect with the eye.  In the old days when us
> older folks were young, the TV camera image was generated the same way,
> with a scanned beam.  So then the generated image matched the displayed
> image.  But Around the end of the 70s when solid state image sensors
> started coming into use, the generated image didn't match that displayed on
> the CRT.  But nobody noticed.  Now, almost all pictures are generated by
> some type of solid state generator and the lines aren't angled, and neither
> are the displayed lines.  So, again, it matches.
>
> The NTSC signal defines 525 lines per "frame," each frame made of two
> "fields" of 262 1/2 lines  (I may have frame and field mixed up.)  In one
> field, the half line is at the top.  It is at the bottom on the other.  But
> out of those 525 total lines, only around 480 (I forget exactly) are
> displayable.  The non-displayed lines are split between the top and
> bottom.  So the two half-lines aren't diplayable.  Those non-displayed
> lines are used for all sorts of things, including closed captioning.
>
> Old analog TVs and monitors make any changes for different types of
> signals;  they just (attempted to ) displayed whatever was thrown at them.
>
> Will
>

[cctalk] Re: Pragmatically [was: Experience using an Altair 8800 ("Personal computer" from 70s)]

[Adrian Godwin via cctalk]

On Tue, May 28, 2024 at 11:08 PM Fred Cisin via cctalk <
cctalk@classiccmp.org> wrote:

> "If your working television sits on top of your non-working television,
> you might be a redneck." - Jeff Foxworthy
>
>
As a child. my parents weren't sufficiently enamoured of televisions to buy
one, but I was given some old ones.
The one on the bottom had working sound and the one on the top had working
video.

[cctalk] Re: oscilloscopes

[Adrian Godwin via cctalk]

This 'scope clock also uses circle generators rather than vectors to
produce well-formed characters. It mentions a Teensy controller so I don't
think it's the original made in this way - the first I heard of was too
long ago for that. But I don't know if it's an update or a separate design.

https://scopeclock.com/


On Thu, Apr 4, 2024 at 2:59 PM Paul Koning via cctalk 
wrote:

>
>
> > On Apr 3, 2024, at 6:32 PM, Rick Bensene  wrote:
> >
> > I wrote:
> >
> >>> The digits are among the nicest looking digits that I've ever seen
> >>> on a CRT display, including those on the CDC scopes as well as IBM >>
> console displays.
> >
> > To which Paul responded:
> >
> >> I have, somewhere, a copy of a paper that describes analog circuits >
> for generating waveforms for digits along the lines you describe.
> >> Might have been from MIT, in the 1950s, but right now I can't find > it.
> >
> >> Found it (on paper): "Generating characters" by Kenneth Perry and
> >> Everett Aho, > Electronics, Jan 3, 1958, pp. 72-75.
> >
> >> Bitsavers has it in the MIT/LincolnLaboratory section:
> https://bitsavers.org/pdf/mit/lincolnLaboratory/Perry_and_Aho__Generating_Characters_-_Electronics_19580103.pdf
> >
> > Very interesting.   Here's a link to the patent for the display system
> on the Wyle Labs calculator:
> >
> >
> https://patentimages.storage.googleapis.com/17/51/58/89c19cee6c60e2/US3305843.pdf
> >
> > The concepts are very similar to the paper written up in ELECTRONICS
> magazine in early 1958 that you found.  Your memory is incredible to have
> been able to have this pop into your mind when you read my description of
> the way the calculator generates its display.
> >
> > Thank you for looking up this article!   It'll provide some nice
> background for the concepts of generating characters this way when I
> finally get to documenting the Wyle WS-01/WS-02 calculators in an Old
> Calculator Museum exhibit.
> >
> > I wonder if the inventor of the display system for the calculator (in
> fact, the inventor of the entire Wyle Labs calculator architecture) had
> read this article at some point prior?
> >
> > I scanned through the patent for the calculator display system looking
> for any reference to the article or any document from MIT relating, and I
> couldn't find anything.
>
> I didn't see any either, and the patent examiners didn't cite any.  Then
> again, it's amazing how often patent examiners miss relevant prior art.
> One example I like to mention is Edwin Armstrong's patent for FM radio,
> which doesn't cite an actual earlier US patent, 1,648,402 from 1927,
> actually filed 12 years before Armstrong's.  Or the prior art centuries
> preceding US 6469...
>
> On the other hand, while the concept is similar the details are rather
> different, and the Wyle design is clearly a whole lot simpler.
>
> > The inventor is still alive, and I have talked to him on the telephone a
> couple of times.   For his advanced age, he is still quite sharp, and
> remembers a lot of the challenges involved with trying to make a
> solid-state electronic calculator that would fit on a (large) desktop using
> early 1960's technology.
>
> It would be neat to ask him about that MIT article.
>
> paul
>
>

[cctalk] Re: Experience using an Altair 8800 ("Personal computer" from 70s)

[Adrian Godwin via cctalk]

Please kill it.
It's a marketing term, defined to suit the needs of the moment.
Even if we ever define it to our satisfaction, nobody else will ever use
that definition.


On Sun, Jun 9, 2024 at 2:32 AM Chuck Guzis via cctalk 
wrote:

>
> Liebe Leser, after consigning most of this thread to the bit bucket over
> the last week or more, I find myself in the position of trying to figure
> out what the latest posts have to do with 'Experience using an Altair
> 8800 ("Personal computer" from 70s)'.  Indeed, it seems that much of the
> thread has been filled with replies having nothing at all to do with the
> MITS 8800.
>
> Please, someone--either kill the thread or start a new one that has
> content relative to the thread title.
>
> Thanks,
> Chuck
>
>