Re: GoTEK SFR1M44-U100...

[Tony Duell via cctalk]

On Fri, Jul 20, 2018 at 5:06 PM, Dave Wade via cctalk
 wrote:
>> -Original Message-
>> From: cctalk  On Behalf Of dwight via
> cctalk
>> Sent: 19 July 2018 22:17
>> To: Liam Proven ; General Discussion: On-Topic and
>> Off-Topic Posts 
>> Subject: Re: GoTEK SFR1M44-U100...
>>
>> One thing that bothers me is the continued emphasis on arithmetic and not
>> on mathematics. The kids growing up today will rarely be more than a few
>> feet from a calculator. The first thing on the math test was the "No
> calculator
>> allowed". I'm not saying that they shouldn't be taught arithmetic but it
> should
>> be the minimum necessary to recreate a multiplication, square, divide or
>> what ever table. Knowing what 43 * 67 is on an exam is useless in
>> determining if the kid can learn calculus or understand how it relates to
> the
>> real world.
>
> All too often they put the numbers in blindly, mis-type,  and get a silly
> answer..

Or quote far too many significant figures. I had an idiot who was asking
for a resistor accurate to 8 significant figures or something. Turned out
it was the series resistor for an LED As I said, an idiot...

> They need enough to know that the answer to that calculation will be
> somewhere
> between 2400 and 3500 and probably be able to tell me its likely to be near
> 40 X 70...
>
> ... so take 43 + 5 * 67
> ... well the windows calculator gives 3216 in standard mode and 378 in
> scientific mode

Or I'm debugging something. I measure the voltage across a resistor as
13.7V. A check with the schematic or the colour bands on the resistor
shows it's a 1.5k Ohm one. So I think 'That means there's a little under
10mA flowing, is that reasonable?'. To have to stop, type the numbers into
a calculator and get 9.1..mA would take longer and not tell me anything
more in most cases.

-tony

RE: GoTEK SFR1M44-U100...

[Dave Wade via cctalk]

> -Original Message-
> From: cctalk  On Behalf Of dwight via
cctalk
> Sent: 19 July 2018 22:17
> To: Liam Proven ; General Discussion: On-Topic and
> Off-Topic Posts 
> Subject: Re: GoTEK SFR1M44-U100...
> 
> One thing that bothers me is the continued emphasis on arithmetic and not
> on mathematics. The kids growing up today will rarely be more than a few
> feet from a calculator. The first thing on the math test was the "No
calculator
> allowed". I'm not saying that they shouldn't be taught arithmetic but it
should
> be the minimum necessary to recreate a multiplication, square, divide or
> what ever table. Knowing what 43 * 67 is on an exam is useless in
> determining if the kid can learn calculus or understand how it relates to
the
> real world.

All too often they put the numbers in blindly, mis-type,  and get a silly
answer..
They need enough to know that the answer to that calculation will be
somewhere 
between 2400 and 3500 and probably be able to tell me its likely to be near
40 X 70...

... so take 43 + 5 * 67 
... well the windows calculator gives 3216 in standard mode and 378 in
scientific mode



> 
> About the hardest math a person might need to know how do do by
> themselves it to figure the tip at a restaurant. And even then, if the
cell
> phone is charged it will do it for them.
> 
> Dwight


Dave
>

Re: GoTEK SFR1M44-U100...

[dwight via cctalk]

One thing that bothers me is the continued emphasis on arithmetic and not on 
mathematics. The kids growing up today will rarely be more than a few feet from 
a calculator. The first thing on the math test was the "No calculator allowed". 
I'm not saying that they shouldn't be taught arithmetic but it should be the 
minimum necessary to recreate a multiplication, square, divide or what ever 
table. Knowing what 43 * 67 is on an exam is useless in determining if the kid 
can learn calculus or understand how it relates to the real world.

About the hardest math a person might need to know how do do by themselves it 
to figure the tip at a restaurant. And even then, if the cell phone is charged 
it will do it for them.

Dwight



From: cctalk  on behalf of Liam Proven via 
cctalk 
Sent: Wednesday, July 18, 2018 4:33:02 AM
To: Discussion: On-Topic and Off-Topic Posts
Subject: Re: GoTEK SFR1M44-U100...

On Tue, 17 Jul 2018 at 19:43, Peter Corlett via cctalk
 wrote:
>
> That's an extraordinary claim that sets off my bullshit detector. Snopes 
> offers
> this commentary: https://www.snopes.com/fact-check/1895-exam/
>
> 50-100 years before you were at school would be roughly 1870-1920, which is
> right at the start of both state-provided schools and compulsory education. 
> The
> UK only raised the school leaving age to 11 in 1893. Truancy was rife, because
> parents still expected their children to work instead and contribute to the
> household. The average child was very poorly educated if at all.
>
> Children actually taking examinations at age 11 are already on the academic
> track for those who are both clever and rich enough to continue their 
> education
> further. It may even be the entrance exam for a posh public school. Your
> average working-class oik is never going to get anywhere near that exam paper.

It's a fair point, and one that did occur to me, but I didn't want to
be even _more_ prolix and hedge it about with disclaimers.

Yes, education for all is a relatively modern thing. In the days when
it was for the elite few, well, I suppose it *would* be more tailored
for the elite, and thus would be challenging to non-elite, even
generations later.

But I am nonetheless surprised at by just how much.

> For fun, have a crack at some of the recent exam papers given to 13 year olds
> hoping for a scholarship: https://www.etoncollege.com/KSpapers.aspx

... wow.

--
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: GoTEK SFR1M44-U100...

[Al Kossow via cctalk]

On 7/18/18 11:15 AM, Chuck Guzis via cctalk wrote:

> essentially a (rather inefficient) serial interface.

where the pulses jitter, and interfere with each other if too close
in the real world.

The only place this shows up in an emulator is
knowing there may be write precompensation occuring from the host
side.

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/18/2018 09:02 AM, Adrian Graham via cctalk wrote:
> On 18 Jul 2018, at 03:22, Fred Cisin via cctalk 
> wrote:
> 
> Could the Gotek firmware, and some drivers on PC's with "HD" or "ED"
> controllers, be kludged together to get faster data transfers?

I found that I could produce a 1.44M (500Kbps) data stream using a 16MHz
ATMega162 with some clever coding.  The trick is to have the track data
already reduced to timing pulses and use the PWM facility in the MCU to
generate them.  I don't see why a carefully-coded STM32F103 routine
couldn't do this, although the problem with that approach is that you
have only 20KB of RAM and expanding that isn't straightforward.

On the other hand, moving up to a STM32F4 series chip would solve that
issue neatly.  Some members of the family even have SDRAM interfaces.  I
have a STM32F429 board with 8MB of SDRAM directly addressable.

--Chuck

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/18/2018 09:03 AM, Liam Proven via cctalk wrote:

> Aha! Interesting. So it's not actually able to be read as if it were a
> diskette? It's sort of hijacking the drive as an alternative I/O
> medium, pulsing data at a stationary drive head, ignoring rotation and
> track positioning?

That's essentially it.  The device does spew out a dummy boot sector if
it's not interacting with the driver software.

But yes, essentially a (rather inefficient) serial interface.  On the
plus side, there's no seek timing.

--Chuck

Re: GoTEK SFR1M44-U100...

[Liam Proven via cctalk]

On Wed, 18 Jul 2018 at 17:53, Chuck Guzis via cctalk
 wrote:
>
> Yup.  I've still got one of the FlashPath units after having taken one
> apart and destroyed it in the process.
>
> There;s a small electromagnet (coil) located where it can be coupled to
> the drive head.  The rest is pretty straightforward--an Atmel MCU, some
> RAM and random logic, along with the driver/sense to the electromagnet.
>
> There's no way for it to determine what cylinder the floppy drive is
> positioned to, nor any way for it to determine when the Index position
> is being passed, which is why it requires a driver on the host to operate.

Aha! Interesting. So it's not actually able to be read as if it were a
diskette? It's sort of hijacking the drive as an alternative I/O
medium, pulsing data at a stationary drive head, ignoring rotation and
track positioning?

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: GoTEK SFR1M44-U100...

[Adrian Graham via cctalk]

On 18 Jul 2018, at 03:22, Fred Cisin via cctalk 
wrote:

Could the Gotek firmware, and some drivers on PC's with "HD" or "ED"
controllers, be kludged together to get faster data transfers?


Replying to myself here but these are the current config file parameters, I
think either setting ibmpc-hdout or one of the pin2 settings will enable
faster transfers.

Drive Emulation:

   -

   *interface* = shugart | ibmpc | ibmpc-hdout | akai-s950 | amiga | jc*
   - Pin assignments of the floppy-drive interface
  - *shugart*: Shugart interface (Amiga, Atari ST, many others)
  - *ibmpc*: IBM PC interface, no output on pin 2
  - *ibmpc-hdout*: IBM PC, high-density-select output on pin 2
  - *akai-s950*: Akai S950
  - *amiga*: Drive ID hack on pin 34. Use *shugart* instead when
  possible.
 - See Amiga-specific hints
 

 for advice on this setting.
  - *jc*: Specified by jumper JC (closed = IBM PC, open = Shugart)
   -

   *host* = unspecified* | acorn | akai | ...
   - Host platform: Improves image-format detection for generic types such
  as IMG
  - *acorn*: Acorn ADFS
  - *akai*: Akai synths (S01, S20, S950)
  - *dec*: DEC (RX33, RX50)
  - *ensoniq*: Ensoniq synths (ASR/TS series, and others)
  - *gem*: General Music (S2, S3, S2R)
  - *memotech*: Memotech
  - *msx*: MSX
  - *pc98*: NEC PC-98
  - *pc-dos*: PC DOS Format (geometry determined from Bios Parameter
  Block)
  - *ti99*: TI-99/4A
  - *uknc*: UKNC, DVK (Soviet PDP-11)
  - *unspecified*: Detection based on image-name suffix only
   -

   *pin02* = auto* | nc | low | high | rdy | nrdy | dens | ndens | chg |
   nchg
   - Manually assign a signal to floppy interface pin 2
  - *auto*: Automatically determined from *interface =* setting
  - *nc*: Unused / No Connection
  - *low*, *high*: Constant low (0v) or high (5v) voltage
  - *rdy*, *nrdy*: Drive ready, or logical complement
  - *dens*, *ndens*: Density mode (HD = 0v), or logical complement
  - *chg*, *nchg*: Disk changed, or logical complement
   -

   *pin34* = auto* | nc | low | high | rdy | nrdy | dens | ndens | chg |
   nchg
   - Manually assign a signal to floppy interface pin 34
   -

   *write-protect* = yes | no*
   - Are images write protected when initially mounted?
 - Protection can be toggled by holding eject for 2 seconds
  - *yes*: Forcibly write-protect images
  - *no*: Respect the FAT read-only attribute
   -

   *side-select-glitch-filter* = 0-255 (0*)
   - Filter glitches in the SIDE-select signal shorter than N microseconds
  - Useful on some old hardware (eg. CP/M systems)
   -

   *track-change* = instant* | realtime
   - Rotational offset of data after a track change
  - *instant*: No rotation during track change
  - *realtime*: Emulate rotation of disk while track is changing
   -

   *index-suppression* = yes* | no
   - Are index pulses suppressed when RDATA and WDATA inactive?
  - Older systems may depend on constant index pulses (eg. BBC Micro)



-- 
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest home computer collection?
t: @binarydinosaursf: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk

On 18 July 2018 at 08:37, Adrian Graham  wrote:

>
> On 18 Jul 2018, at 03:22, Fred Cisin via cctalk 
> wrote:
>
> Could the Gotek firmware, and some drivers on PC's with "HD" or "ED"
> controllers, be kludged together to get faster data transfers?
>
>
> Good question. I’ll ask since that could be implemented with a line in the
> config file. Keir is constantly updating the firmware to add extra features
> so it might be there already.
>
> 3" and 3.25" were also almost completely compatible with the "standard" 34
> pin interface.  Although I remember one drive that had 5V and 12V swapped
> in its 4 pin power connector!   And my 8" drives did not standardize power
> connector and requirements.
>
>
> Early Amigas had +5 and +12 swapped . I didn’t realise this and the first
> time I hooked up a Gotek to my A500 it cooked the USB stick but thankfully
> didn’t kill the logic on the board.
>
> --
> adrian/witchy
> Owner of Binary Dinosaurs, the UK's biggest home computer collection?
> t: @binarydinosaursf: facebook.com/binarydinosaurs
> w: www.binarydinosaurs.co.uk
>
>
>
>

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/18/2018 04:19 AM, Liam Proven via cctalk wrote:

> https://www.amazon.com/SmartDisk-FlashPath-Floppy-Adapter-SmartMedia/dp/B5QXW7

Yup.  I've still got one of the FlashPath units after having taken one
apart and destroyed it in the process.

There;s a small electromagnet (coil) located where it can be coupled to
the drive head.  The rest is pretty straightforward--an Atmel MCU, some
RAM and random logic, along with the driver/sense to the electromagnet.

There's no way for it to determine what cylinder the floppy drive is
positioned to, nor any way for it to determine when the Index position
is being passed, which is why it requires a driver on the host to operate.

--Chuck

Re: GoTEK SFR1M44-U100...

[Liam Proven via cctalk]

On Tue, 17 Jul 2018 at 19:43, Peter Corlett via cctalk
 wrote:
>
> That's an extraordinary claim that sets off my bullshit detector. Snopes 
> offers
> this commentary: https://www.snopes.com/fact-check/1895-exam/
>
> 50-100 years before you were at school would be roughly 1870-1920, which is
> right at the start of both state-provided schools and compulsory education. 
> The
> UK only raised the school leaving age to 11 in 1893. Truancy was rife, because
> parents still expected their children to work instead and contribute to the
> household. The average child was very poorly educated if at all.
>
> Children actually taking examinations at age 11 are already on the academic
> track for those who are both clever and rich enough to continue their 
> education
> further. It may even be the entrance exam for a posh public school. Your
> average working-class oik is never going to get anywhere near that exam paper.

It's a fair point, and one that did occur to me, but I didn't want to
be even _more_ prolix and hedge it about with disclaimers.

Yes, education for all is a relatively modern thing. In the days when
it was for the elite few, well, I suppose it *would* be more tailored
for the elite, and thus would be challenging to non-elite, even
generations later.

But I am nonetheless surprised at by just how much.

> For fun, have a crack at some of the recent exam papers given to 13 year olds
> hoping for a scholarship: https://www.etoncollege.com/KSpapers.aspx

... wow.

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: GoTEK SFR1M44-U100...

[Liam Proven via cctalk]

On Wed, 18 Jul 2018 at 01:11, Eric Smith via cctalk
 wrote:
>
> Unfortunately not. A floppy drive doesn't have any way to know what sector
> the host wants, so a drive emulator has to simulate the rotation process.

On that note... Does anyone know how NV-memory-to-floppy emulators worked?

E.g. these Smartmedia to floppy adaptors:

https://www.ebay.com/p/Olympus-Floppy-Disk-Adapter-for-Smart-Media-Flash-Path-Mafp-1u/1307808939

or

https://www.amazon.com/SmartDisk-FlashPath-Floppy-Adapter-SmartMedia/dp/B5QXW7

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: GoTEK SFR1M44-U100...

[Adrian Graham via cctalk]

> On 18 Jul 2018, at 03:22, Fred Cisin via cctalk  wrote:
> 
> Could the Gotek firmware, and some drivers on PC's with "HD" or "ED" 
> controllers, be kludged together to get faster data transfers?

Good question. I’ll ask since that could be implemented with a line in the 
config file. Keir is constantly updating the firmware to add extra features so 
it might be there already.

> 3" and 3.25" were also almost completely compatible with the "standard" 34 
> pin interface.  Although I remember one drive that had 5V and 12V swapped in 
> its 4 pin power connector!   And my 8" drives did not standardize power 
> connector and requirements.

Early Amigas had +5 and +12 swapped . I didn’t realise this and the first time 
I hooked up a Gotek to my A500 it cooked the USB stick but thankfully didn’t 
kill the logic on the board.

-- 
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest home computer collection?
t: @binarydinosaursf: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk

Re: GoTEK SFR1M44-U100...

[Fred Cisin via cctalk]

On 07/17/2018 04:11 PM, Eric Smith via cctalk wrote:

When 3.5-inch floppy drives and hard drives were introduced, most used the
same 34-pin interfaces as their 5.25-inch counterparts.


On Tue, 17 Jul 2018, Chuck Guzis via cctalk wrote:

Can't say much about 3.5" hard drives (the only really early ones I've
seen are standard ST505-type 2-cable interface).


I interpreted Eric's comment as meaning that the 3.5" hard drives used 
same interface as the 5.25. inch hard drives (34 pin and 20 pin), and the 
3.5" floppy would be same as 5.25" floppy 34 pin.



But initially, the 3.5' floppies used a 26-pin interface (13 signal lines):
http://bitsavers.informatik.uni-stuttgart.de/pdf/sony/floppy/Sony_Micro_Floppy_Disk_Drive_Model_0A-D30V_OEM_Manual_Mar82.pdf
And of course, the drives spun at 600 RPM, which was really nice if you
were used to 8" or 5.25" drives.   The Drivetek 5.25" high-capacity
drives would also spin at 600 RPM when a conventional floppy was
used--again, a nice feature.


Could the Gotek firmware, and some drivers on PC's with "HD" or "ED" 
controllers, be kludged together to get faster data transfers?


ALthough the early 3.5" were 600 RPM and 26 pin, they soon changed over to 
34 pin. (some MS-DOS 2.11 laptops)   I'm assuming to make them a drop-in 
replacement for 5.25".

But, yes, when first introduced, they were not yet 34 pin.


And, of course there were a few 5.25" drives that were not the standard 34 
pin interface, such as Apple.  (SA390 (SA400 without the "logic" board"))


My first "1.2M" 5.25" drive (Mitsubishi EARLY 4854?) had a 50 pin 
connector!  That made me think that they were targetting 8" replacement, 
rather than 5.25" storage increase.


Unsubstantiated story from a Microsoft person was that during the initial 
stages of AT-BIOS and DOS 3.00 programming, they thought that there was an 
8" machine coming.



3" and 3.25" were also almost completely compatible with the "standard" 34 
pin interface.  Although I remember one drive that had 5V and 12V swapped 
in its 4 pin power connector!   And my 8" drives did not standardize power 
connector and requirements.

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/17/2018 04:11 PM, Eric Smith via cctalk wrote:

> When 3.5-inch floppy drives and hard drives were introduced, most used the
> same 34-pin interfaces as their 5.25-inch counterparts.

Can't say much about 3.5" hard drives (the only really early ones I've
seen are standard ST505-type 2-cable interface).

But initially, the 3.5' floppies used a 26-pin interface (13 signal lines):

http://bitsavers.informatik.uni-stuttgart.de/pdf/sony/floppy/Sony_Micro_Floppy_Disk_Drive_Model_0A-D30V_OEM_Manual_Mar82.pdf

And of course, the drives spun at 600 RPM, which was really nice if you
were used to 8" or 5.25" drives.   The Drivetek 5.25" high-capacity
drives would also spin at 600 RPM when a conventional floppy was
used--again, a nice feature.

FWIW,
Chuck

Re: GoTEK SFR1M44-U100...

[Fred Cisin via cctalk]

On Tue, 17 Jul 2018, Eric Smith via cctalk wrote:

more history of it than you probably wanted:


I think that it is worth adding in the amusing anecdote of the name 
"Seagate".


Alan Shugart as "Shugart Associates" changed 8" drives to what became the
industry standard form.  And then created the SA400 5.25" drive.

There is some dispute over the creation of 5.25".  One story goes that 
Adkisson (of Shugart Associates) was talking with Wang, who wanted a 
smaller drive and diskette.  When asked what size did they want, Wang 
picked up the bar napkin.  That bar napkin became the model for the 5.25" 
diskette.Massaro denies the story.



Shugart sold "Shugart Associates" to Xerox.

Later, Shugart formed "Shugart Technology", to develop small hard drives.
Xerox lawyers objected to the name, and Shugart had to change it to 
"Seagate Technology".
Which goes to show you, do not name your company after yourself, or 
selling the company could cost you your name.

Re: GoTEK SFR1M44-U100...

[Eric Smith via cctalk]

On Tue, Jul 17, 2018 at 2:49 PM, Grant Taylor via cctalk <
cctalk@classiccmp.org> wrote:

> I conceptually get that the GoTEK can't go any faster than the Floppy's
> IDE (I thought floppy was a derivative of IDE.) bus can carry the data.


IDE came much later and isn't very similar to the floppy interface. Here's
more history of it than you probably wanted:

IBM invented the 8-inch floppy drive and had a proprietary interface to it
(discussed here recently). Memorex made plug-compatible drives, but the IBM
interface did not become an industry standard.  With IBM's earliest floppy
drives (23FD "Minnow"), even the medium, rotation rate, data encoding, and
index hole locations weren't compatible with what became the industry
standard. Minnow was shipped to customers as part of IBM mainframes and
control units as a read-only device to load microcode, though obviously
internally IBM had equipment to write the disks.  IBM redesigned it as the
33FD "Igar", and that did set an industry standard for the media format,
but still did not standardize the electrical interface.

The Shugart SA-900/901 drive standardized a 50-pin interface for eight-inch
floppy drives. The Shugart SA-4000 series 14-inch winchester hard disk
drives used a similar but not identical 50-pin interface. The SA-1000
series 8-inch winchester hard drives moved the data to a "radial" interface
using separate connectors for each drive, while keeping the 50-pin
interface for control and status. The SA-4000 and SA-1000 series
established defacto standards for early winchester drives.

Shugart invented the 5.25-inch floppy drive. The Shugart SA-400 drive
standardized a 34-pin interface for 5.25-inch floppy drives, which was for
the most part a subset of the 50-pin interface, with the pins rearranged.
Most 5.25-inch floppy drives provided spindle motor on/off control over the
interface but had no head load solenoid, where previously most 8-inch
floppy drives gave the interface control over the head load solenoid but
had no spindle motor control. (Many of the later 8-inch half-height floppy
drives followed this trend.)

The Shugart Technology (a different company, later renamed Seagate) ST-506
drive standardized a 34-pin interface for 5.25-inch winchester hard drives,
which was in most regards a subset of the SA-1000 interface, with a
different pinout, and a different differential signalling standard (RS-422)
on the radial data connector.

When 3.5-inch floppy drives and hard drives were introduced, most used the
same 34-pin interfaces as their 5.25-inch counterparts.

All of the drives and interfaces previously described are bit serial, with
discrete control lines for all drive functions. The interfaces have no
parallel bus structures for either data or control.

There were third-party hard disk systems for the IBM PC, but the first
official IBM hard disks for PCs were for the PC/XT and PC/AT. The PC/AT
controller in particular was based on a Western Digital design.The IDE hard
disk interface was essentially the host interface of the Western Digital
hard disk controller. As such, it uses a parallel data bus for both data
and commands. There are no discrete drive control signals.



> I was hoping to avoid some timings of the physical aspects of spinning the
> disk and seeking.
>

Unfortunately not. A floppy drive doesn't have any way to know what sector
the host wants, so a drive emulator has to simulate the rotation process.
Most floppy interfaces, including those used on PCs, don't have buffered
seek, so there's no easy way for the emulator to short-circuit the step
process either, though you could possibly tell the computer to configure
the floppy disk controller chip for a faster seek rate.

Re: Why GoTEK SFR1M44-U100 is slow...

[Fred Cisin via cctalk]

Just a question, you’re not expecting the Gotek to whizz files onto the 
Compaq are you?


On Tue, 17 Jul 2018, Grant Taylor via cctalk wrote:

No, not as such.
It may be something modern emulating a floppy drive but it also has to 
emulate the floppy drive rotational speed so it should be the same speed as 
a real drive.
I am guessing that there is some false hope ~> expectation on my part that 
things might be a little bit faster than they were.
That being said, there is every chance that this process was doing extra work 
and likely verifying the format (I think format has a flag to test a floppy 
as it's formatted), thus making it take longer.





The MS-DOS VERIFY command meant that every time that a sector was written, 
the computer would then check the CRC, and confirm that it was a valid 
sector.  Contrary to popular ASSUMPTION, it absolutely did NOT compare the 
content of the sector with what it should be.  (re-read sector and 
compare?  Nope, just confirm that it is readable)  A drive with dead write 
electronics can "write" and VERIFY, simply because the unaltered previous 
content does VERIFY as valid sectors).


Some people would turn VERIFY OFF, and disable PARITY, in a performance 
attempt because they assumed that it wasn't actually doing anything.

Q: Do you want to know whether there are errors?

A FORMAT VERIFY that formats all tracks, and THEN verifies them is slower, 
but more reliable than format and verify of each track, since it is a 
recheck that each track is written on the correct cylinder.  A Format and 
verify before changing track, on a drive with broken stepper, could format 
and verify every track all on the same cylinder.




I conceptually get that the GoTEK can't go any faster than the Floppy's IDE 
(I thought floppy was a derivative of IDE.) bus can carry the data. I was 
hoping to avoid some timings of the physical aspects of spinning the disk and 
seeking.


Floppy interface (SA800/SA400 and derivatives) was long before the IDE 
("Integrated Device Electronics") hard disk interface, so the derivation 
is mostly the other direction.


The disk spins at 360 (8", 1.2M, NEC) or 300 (5.25", 3.5") RPM. (180RPM 
for Weltec 1.2M kludge to get 1.2M on XT; 600RPM for one of the Sony 3.5")


The data transfer rate was
125,000 bits per second (5.25" SD)
250,000 bits per second (8" SD, 5.25" DD, 3.5" DD, Weltec 1.2M)
300,000 bits per second (360K disk in 1.2M drive)
500,000 bits per second (8" DD, 1.2M, 3.5" HD)
1,000,000 bits per second (2.8M)

Each controller only supported some of those.
5150 was 250,000.
5170 (AT) was 250,000, 300,000, 500,000.
Spinning the disk at 300RPM, and transferring at 250,000 bps controlled 
the positioning of the bits on the track.
Spinning faster, even if only virtual, can't change that data transfer 
rate.  Well ALMOST not.  Weltec had a slower than normal drive to permit 
1.2M on slower controllers, and Sony had a 3.5" drive that sun at 600RPM 
requiring controller with faster data transfer rate).
To over-simplify, you can think of the rotational speed as being solely 
to match the controller data transfer rate; and therefore, not helped by 
this.


So, those preset data transfer rates in the controller are the sole 
determining factor of the speed that you will get.



On the other hand, SEEK could be improved.
You could probably get some minor speed improvement by tampering with 
the seek time parameters!  The computer waits after a "STEP" command to 
give the drive time to step and settle.  When IBM used the Qumetrak 142 
drives (PCJr), they had to release a new version of PD-DOS (2.10) to 
slow down that time for the SLOW-ASS drives.  Check out INT 1Eh (pointer 
to where those vaariables are stored)


So, other than the possibility of a faster virtual SEEK/STEP time, this 
will be exactly the same speed as a real floppy.


It also might be possible to create new firmware AND drivers on PC, that 
would fake being at 600RPM, to let the FDC use its 500,000 bps data 
transfer rate.  Or use the 1,000,000 bps rate on 2.8M capable controllers.



I think I've been messing with virtualization too much that can simply do 
things a LOT faster because more of the computer is emulated.  (This does 
come with it's own problems too.)


yep.  that would also does away with the FDC data transfer rate 
bottleneck.







It will be interesting to see the track count on the OLED once I install it.


That will be a sweet add-on



Bit like watching a kettle boil :)

Or watching paint dry.

Or grass growing.


--
Grumpy Ol' Fred ci...@xenosoft.com

Re: GoTEK SFR1M44-U100...

[Grant Taylor via cctalk]

On 07/17/2018 02:04 PM, Adrian Graham via cctalk wrote:
Just a question, you’re not expecting the Gotek to whizz files onto the 
Compaq are you?


No, not as such.

It may be something modern emulating a floppy drive but it also has 
to emulate the floppy drive rotational speed so it should be the same 
speed as a real drive.


I am guessing that there is some false hope ~> expectation on my part 
that things might be a little bit faster than they were.


That being said, there is every chance that this process was doing extra 
work and likely verifying the format (I think format has a flag to test 
a floppy as it's formatted), thus making it take longer.


I conceptually get that the GoTEK can't go any faster than the Floppy's 
IDE (I thought floppy was a derivative of IDE.) bus can carry the data. 
I was hoping to avoid some timings of the physical aspects of spinning 
the disk and seeking.


I think I've been messing with virtualization too much that can simply 
do things a LOT faster because more of the computer is emulated.  (This 
does come with it's own problems too.)


One thing that sometimes makes it seem slow to me is that I don’t 
have the little piezo speaker for mine so you’re getting no audible 
feedback, and with no OLED either you have no idea about which tracks 
its reading, etc.


Fortunately for me, my GoTEK does have an activity LED.  Apparently some 
models don't even have that.


It will be interesting to see the track count on the OLED once I install it.

As it is, I go from starting to assumed finish without any progress 
indicator.



Bit like watching a kettle boil :)


Or watching paint dry.



--
Grant. . . .
unix || die

Re: GoTEK SFR1M44-U100...

[Adrian Graham via cctalk]

> On 17 Jul 2018, at 18:49, Grant Taylor via cctalk  
> wrote:
> 
> I don't know if the GoTEK is itself slow or if it's a result of what the 
> computer was doing with it.  —  My only experience was trying to have a 
> Compaq System Utility Partition back itself up to the GoTEK.  The first 
> ""disk worked without a problem.  The backup routine fails complaining about 
> a file after formatting the second disk.  I suspect this may be more source 
> than the destination.

Just a question, you’re not expecting the Gotek to whizz files onto the Compaq 
are you? It may be something modern emulating a floppy drive but it also has to 
emulate the floppy drive rotational speed so it should be the same speed as a 
real drive. One thing that sometimes makes it seem slow to me is that I don’t 
have the little piezo speaker for mine so you’re getting no audible feedback, 
and with no OLED either you have no idea about which tracks its reading, etc.

Bit like watching a kettle boil :) 

-- 
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest home computer collection?
t: @binarydinosaursf: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/17/2018 10:49 AM, Grant Taylor via cctalk wrote:

> I'm sure there is a healthy dose of my ignorance of using the GoTEK.
> There was zero documentation that came with it.  Online searches turn up
> a myriad of versions for the different models and it's all combining
> into a … cesspool seems like the proper word.
> 
> I think I'm going to like the GoTEK as I get more experience with it.  I
> am planing on trading out the firmware and moding it to add an OLED
> display so I'll have more information on what it's doing.

Why not put a scope on the INDEX pin output and see if it's nice and
regular or it skips revs when the firmware has to ge fetch a track's
worth of data?

Just a suggestion...

--Chuck

Re: GoTEK SFR1M44-U100...

[Grant Taylor via cctalk]

On 07/13/2018 03:12 PM, Grant Taylor via cctalk wrote:
Does anyone have any experience with the GoTEK SFR1M44-U100 floppy drive 
emulator that reads ""images from a USB flash drive?


In case anyone is interested.

I have received my GoTEK and my initial impression is something between 
neutral and positive.


I'm still running the stock firmware on it but plan to transition to 
FlashFloppy (?) after my new soldering iron arrives.  (My last one 
didn't make a cross country move.)


I don't know if the GoTEK is itself slow or if it's a result of what the 
computer was doing with it.  —  My only experience was trying to have a 
Compaq System Utility Partition back itself up to the GoTEK.  The first 
""disk worked without a problem.  The backup routine fails complaining 
about a file after formatting the second disk.  I suspect this may be 
more source than the destination.


I'm sure there is a healthy dose of my ignorance of using the GoTEK. 
There was zero documentation that came with it.  Online searches turn up 
a myriad of versions for the different models and it's all combining 
into a … cesspool seems like the proper word.


I think I'm going to like the GoTEK as I get more experience with it.  I 
am planing on trading out the firmware and moding it to add an OLED 
display so I'll have more information on what it's doing.




--
Grant. . . .
unix || die

Re: GoTEK SFR1M44-U100...

[Peter Corlett via cctalk]

On Tue, Jul 17, 2018 at 03:21:43PM +0200, Liam Proven via cctalk wrote:
[...]
> But then, when I look at school examination papers from 50 or 100 years
> before I was at school, *I'm* terrified. I feel like I am retarded, compared
> to schoolchildren of the turn of the 20th century who were expected by 11 to
> be fluent in 3-4 foreign languages, to play several musical instruments, to
> be able to confidently quote literature in multiple languages, and so on.

That's an extraordinary claim that sets off my bullshit detector. Snopes offers
this commentary: https://www.snopes.com/fact-check/1895-exam/

50-100 years before you were at school would be roughly 1870-1920, which is
right at the start of both state-provided schools and compulsory education. The
UK only raised the school leaving age to 11 in 1893. Truancy was rife, because
parents still expected their children to work instead and contribute to the
household. The average child was very poorly educated if at all.

Children actually taking examinations at age 11 are already on the academic
track for those who are both clever and rich enough to continue their education
further. It may even be the entrance exam for a posh public school. Your
average working-class oik is never going to get anywhere near that exam paper.

For fun, have a crack at some of the recent exam papers given to 13 year olds
hoping for a scholarship: https://www.etoncollege.com/KSpapers.aspx

Re: GoTEK SFR1M44-U100...

[Grant Taylor via cctalk]

On 07/17/2018 07:21 AM, Liam Proven via cctalk wrote:

…but they don't see them as particularly important.


Sadly, many of my generation and younger, don't understand that the 
perception of importance often doesn't match the actual importance.




--
Grant. . . .
unix || die

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/17/2018 09:50 AM, Eric Smith via cctalk wrote:

> The latter, two single single-sided heads, each opposed by a pressure pad.
> 
> Aside from the provision for extra fingerprints, a problem with this scheme
> was that they varied the rotation rate depending on the position of the
> head in use. Unfortunately since there was only a single actuator, when the
> top head was near the inside, the bottom was near the outside, and vice
> versa. Except for the middle few tracks, it was never fast to switch from
> one head to the other without seeking. The logical disk organization was
> all of side zero followed by all of side one, rather than by cylinder.

It was probably one of the more insane things that Apple did.  871K
using variable speed spindle motors (very irritating if you were a user)
and GCR.  Just across the street on Bubb Road, we were getting 960K
using GCR on stock Micropolis drives in 1978.  No fancy zoned recording
schemes or non-standard drives.

The Apple Mentality:  NIH sometimes backfires badly.

--Chuck

Re: GoTEK SFR1M44-U100...

[Eric Smith via cctalk]

On Mon, Jul 16, 2018 at 4:58 PM, Fred Cisin  wrote:

> On the Lisa "Twiggy" diskettes, they made special provision to get more
>>> thumb prints.
>>>
>>
> On Mon, 16 Jul 2018, Eric Smith wrote:
>
>> I imagine you're aware of the actual reason for the two diametrically
>> opposing jacket cutouts for the read/write heads.
>>
>
> I'm NOT sure.  I speculate:
> 2) To have two sets of heads.  Either performance, or simply two single
> sided heads, to have felt pad instead of head to head pressure
>

The latter, two single single-sided heads, each opposed by a pressure pad.

Aside from the provision for extra fingerprints, a problem with this scheme
was that they varied the rotation rate depending on the position of the
head in use. Unfortunately since there was only a single actuator, when the
top head was near the inside, the bottom was near the outside, and vice
versa. Except for the middle few tracks, it was never fast to switch from
one head to the other without seeking. The logical disk organization was
all of side zero followed by all of side one, rather than by cylinder.

Re: GoTEK SFR1M44-U100...

[Liam Proven via cctalk]

On Tue, 17 Jul 2018 at 14:36, Noel Chiappa via cctalk
 wrote:
>
> Yikes.
>
> Send them this:
>
>   http://www.chiappa.net/~jnc/tech/sflovers/

*Chuckle*

I doubt they'd understand. This quiz was in the basement bar of a
youth hostel. I would guesstimate that these kids are all young enough
that they don't remember the 20th century.

They're highly media-literate -- my team only won by 1 point, although
if they'd listened to me it would have been 3 -- but the quizmaster
struggled with the task of reading the team names out.

Ours was called "Intravenous de Milo". This had to be explained to
him. He confessed embarrassment that he didn't know the reference --
he hadn't heard of the sculpture -- nor did he know the word
"intravenous".

Most team names were puns. He struggled with every one, simply to pronounce it.

To mark another team's paper, you need to be able to add up and count
to between 10 and 12. Several times we've had to ask for a recount
because that much mental arithmetic is hard for them. The former quiz
mistress, who's ~32, totally them wrongly about 3 weeks ago and gave
the prize to someone else who'd got 3 less than us.

These are abstract skills that are not handled well by millennial kids.

It scares the pants off me, because in a decade, some of these people
will be running companies. Some will employ thousands.

These are smart, monied, well-travelled kids, travelling the world
alone for fun. They're probably among the brighter of their
generation.

But then, when I look at school examination papers from 50 or 100
years before I was at school, *I'm* terrified. I feel like I am
retarded, compared to schoolchildren of the turn of the 20th century
who were expected by 11  to be fluent in 3-4 foreign languages, to
play several musical instruments, to be able to confidently quote
literature in multiple languages, and so on.

My generation were considerably dumber than that.

Now, my generation is running things -- I'm broadly of an age with the
government members of most of the English-speaking world.

And they are, very evidently, making a total mess of it.

So I am perversely reassured that it's not just me. Nope, my
generation were dumb too. Yes, the next generation seem very stupid to
me, but they know stuff I don't know, have skills I don't have. I
marvel that they lack skills that seem basic to me, like the "three
Rs", but they don't see them as particularly important.

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: GoTEK SFR1M44-U100...

[Noel Chiappa via cctalk]

> From: Liam Proven

> one of the questions was about "the early days of the old-time
> internet, if you're old and you've been online forever."
> It was about Myspace.

Yikes.

Send them this:

  http://www.chiappa.net/~jnc/tech/sflovers/

Noel

Re: GoTEK SFR1M44-U100...

[Liam Proven via cctalk]

On Tue, 17 Jul 2018 at 03:41, Fred Cisin via cctalk
 wrote:
>
> On 8", notch is write protect; no notch is write enabled.
> on 5.25", notch is write enabled; no notch is write protected.
> I think that that justifies calling the 8" a "write protect notch", and
> calling the 5.25" a "write enable notch".

I was not aware of that.

Thank you, once again, ClassicCmp, for making me feel relatively young.

I think I have seen live working systems with 8" floppies about twice
in my entire working life, both in the late 1980s. I have never used a
system with them, not even once.

I'm 50 and my first memory of any kind is the first moon landing.

Last night, in a pub quiz, which to the organizers'  amazement we won
-- we were the "old people" team (3 × ~50, 1 × ~35), when one of the
questions was about "the early days of the old-time internet, if
you're old and you've been online forever."

It was about Myspace.

>_<

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: GoTEK SFR1M44-U100...

[Liam Proven via cctalk]

On Tue, 17 Jul 2018 at 00:17, Fred Cisin via cctalk
 wrote:
>
> Or maybe it's the need for fingerprint oils on the media!  3.5" keeps
> fingers away more than 5.25 or 8".  On the Lisa "Twiggy" diskettes, they
> made special provision to get more thumb prints.

*Chuckle*

Even if I never saw them, IKWYM.

I am slowly staggering towards having my ZX Spectrum machines up and
running again -- and I hope my QL, too. They both have 5¼" drives.
When I kitted out my Spectrum with an MGT DISCiPLE and a single DS/DD
80t drive, circa 1986 or so, 5¼" drives were ~½ the price of 3½" ones,
and the media were much less -- maybe 1/10th of the price.

Due to acute media shortage, if my old disks can still be read, now
I'm looking at moving over to 3½" drives and media.

I do have a µSD card interface too, but it doesn't feel the same...

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: GoTEK SFR1M44-U100...

[Liam Proven via cctalk]

On Mon, 16 Jul 2018 at 17:31, Chuck Guzis via cctalk
 wrote:
>
> There were a couple of versions of web-browser with OS that fit on a
> 1.44M floppy.

I know about the famous QNX Demo Disk. It's the only one I knew of, though.

http://toastytech.com/guis/qnxdemo.html

Although I guess I could, just for laughs, try to do a modern DR-DOS +
web browser demo disk... I have some already...

https://liam-on-linux.livejournal.com/58013.html

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: GoTEK SFR1M44-U100...

[dwight via cctalk]

I still don't know for sure which way to do 8 inch compared to 5.25. I usually 
try to write both ways but soon forget which is which.

It won't do any good to tell me as I'll still forget. I just remember the 8 
inch drives were different.

Another good quiz question is where the index hole was on a 8 inch disk for the 
various flavors of 8 inch disk.

Dwight



From: cctalk  on behalf of Chuck Guzis via 
cctalk 
Sent: Monday, July 16, 2018 7:28:19 PM
To: Fred Cisin via cctalk
Subject: Re: GoTEK SFR1M44-U100...

On 07/16/2018 06:40 PM, Fred Cisin via cctalk wrote:

> On 8", notch is write protect; no notch is write enabled.
> on 5.25", notch is write enabled; no notch is write protected.
> I think that that justifies calling the 8" a "write protect notch", and
> calling the 5.25" a "write enable notch".
> Used 8" drives that I got sometimes had write-enable tabs in them that
> had fallen off.  Once out of the enclosure, you did not need tiny
> fingers to work on 8" drives.

Well, it's a matter of half-full/half-empty.  The 5.25" notch was always
called write-protect, so go figure.

I've got a few old 5.25" DSDD floppies with a very clover
adaptation--they use a little aluminum slider in the jacket so that one
doesn't have deal with finding sticky things for protection.

The placement of the 5.25" notch, under whatever terminology--on the
jacket *side* was very convenient.  It was possible to poll the sensor
to detect disk insertion/removal without the need for powering the
spindle motor.   I coded some stuff up in the late 70s for a "Put that
back!" alarm when the disk contained files open for writing.

I've got some 3M-branded 8" notched floppies that came with a strip of
transparent *red* stick-ons.   The result was that even when applied,
the disk to some drives was still write-protected.   Very frustrating
the first time encountered.

--Chuck

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/16/2018 06:40 PM, Fred Cisin via cctalk wrote:

> On 8", notch is write protect; no notch is write enabled.
> on 5.25", notch is write enabled; no notch is write protected.
> I think that that justifies calling the 8" a "write protect notch", and
> calling the 5.25" a "write enable notch".
> Used 8" drives that I got sometimes had write-enable tabs in them that
> had fallen off.  Once out of the enclosure, you did not need tiny
> fingers to work on 8" drives.

Well, it's a matter of half-full/half-empty.  The 5.25" notch was always
called write-protect, so go figure.

I've got a few old 5.25" DSDD floppies with a very clover
adaptation--they use a little aluminum slider in the jacket so that one
doesn't have deal with finding sticky things for protection.

The placement of the 5.25" notch, under whatever terminology--on the
jacket *side* was very convenient.  It was possible to poll the sensor
to detect disk insertion/removal without the need for powering the
spindle motor.   I coded some stuff up in the late 70s for a "Put that
back!" alarm when the disk contained files open for writing.

I've got some 3M-branded 8" notched floppies that came with a strip of
transparent *red* stick-ons.   The result was that even when applied,
the disk to some drives was still write-protected.   Very frustrating
the first time encountered.

--Chuck

Re: GoTEK SFR1M44-U100...

[Fred Cisin via cctalk]

I am reminded of an episode of "Computer Bowl" (TV game show).  Nobody
on Bill Gates' team could answer WHERE the write protect notch is on an
8 inch diskette!


On Mon, 16 Jul 2018, Chuck Guzis via cctalk wrote:

Indeed, I couldn't even tell you.  I *do* know where the write *enable*
notch is, however.


Their team couldn't have come up with that, either.  And, they DID have an 
opportunity to give an adequately detailed answer to such things.


On 8", notch is write protect; no notch is write enabled.
on 5.25", notch is write enabled; no notch is write protected.
I think that that justifies calling the 8" a "write protect notch", and 
calling the 5.25" a "write enable notch".
Used 8" drives that I got sometimes had write-enable tabs in them that had 
fallen off.  Once out of the enclosure, you did not need tiny fingers to 
work on 8" drives.



I learned the hard way to distribute 5.25" software on no-notch disks,
after somebody peeled off the write protect tab in order to infect one 
with "STONED", and then claimed that we had sent it that way.  The serial 
numbers before and after were local, so I was able to confirm that it was 
ONLY that one disk.
When I switched to no-notch disks, I jumpered an SA455 for writing to 
non-notch disks.  I sure hope that I remember to jumper it back before I 
give that drive away.  I never had enough volume to justify a dedicated 
duplicator.)



I can't ever recall hearing anyone ever calling the plastic ring on
open-reel mag tape a "write-protect" ring.

I've sometimes wondered how many 5.25" diskettes got inadvertently
clobbered because of the reversal of the sense of the notch.


A lot.  I'm ambivalent about which way is better, but that is not a good 
kind of thing to change.

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/16/2018 03:58 PM, Fred Cisin via cctalk wrote:

> I am reminded of an episode of "Computer Bowl" (TV game show).  Nobody
> on Bill Gates' team could answer WHERE the write protect notch is on an
> 8 inch diskette!

Indeed, I couldn't even tell you.  I *do* know where the write *enable*
notch is, however.

I can't ever recall hearing anyone ever calling the plastic ring on
open-reel mag tape a "write-protect" ring.

I've sometimes wondered how many 5.25" diskettes got inadvertently
clobbered because of the reversal of the sense of the notch.

--Chuck

Re: GoTEK SFR1M44-U100...

[Fred Cisin via cctalk]

On the Lisa "Twiggy" diskettes, they made special provision to get more
thumb prints.


On Mon, 16 Jul 2018, Eric Smith wrote:

:-)
I imagine you're aware of the actual reason for the two diametrically
opposing jacket cutouts for the read/write heads.


I'm NOT sure.  I speculate:
1) for users who put it in the wrong way.  In which case, they should have 
had FOUR cutouts, AND a reversing motor and/or full track read and 
extraction to include upside down.  (there are EIGHT ways that a 5.25 will 
fit into the drive).

(cf. reasons for SINGLE button on Apple mouse)

2) To have two sets of heads.  Either performance, or simply two single 
sided heads, to have felt pad instead of head to head pressure




I am reminded of an episode of "Computer Bowl" (TV game show).  Nobody on 
Bill Gates' team could answer WHERE the write protect notch is on an 8 
inch diskette!

Re: GoTEK SFR1M44-U100...

[Eric Smith via cctalk]

On Mon, Jul 16, 2018 at 4:17 PM, Fred Cisin via cctalk <
cctalk@classiccmp.org> wrote:

> On the Lisa "Twiggy" diskettes, they made special provision to get more
> thumb prints.
>

:-)

I imagine you're aware of the actual reason for the two diametrically
opposing jacket cutouts for the read/write heads.

Eric

Re: GoTEK SFR1M44-U100...

[Fred Cisin via cctalk]

On Mon, 16 Jul 2018, Chuck Guzis via cctalk wrote:

The problem with 3.5" floppies for me was the declining quality of the
media as manufacturers raced toward the bottom pricing point.
IIRC that initially, a box of 10 3.5" DSHD floppies was about $50--at
least that's what I paid for a box of Fujis back then.  None from that
original box have survived.  Initially, 3.5" DSED cost about the same.
On the other hand, I still have some of my 8" floppies from the 1970s
that are quite readable today.


In addition to the race to the bottom declining quality, the reliability 
may also have been slightly affected by

change in linear density (physical length of track),
48tpi V 135tpi,
reduced write current (with 300 Oersted V 600 V 750)


Or maybe it's the need for fingerprint oils on the media!  3.5" keeps 
fingers away more than 5.25 or 8".  On the Lisa "Twiggy" diskettes, they 
made special provision to get more thumb prints.
If it were only still in the public consciousness, I can imagine CSI 
dialog, "They cleaned up the crime scene, but I know one place where we 
can get a thumbprint of the computer operator!"


--
Grumpy Ol' Fred ci...@xenosoft.com

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/16/2018 07:38 AM, Liam Proven via cctalk wrote:

> I did that on occasion. So did some OS distributions, just to keep the
> number of boot diskettes down to just 3 and still be able to boot a
> bloated 1990s OS off floppy, plus enough drivers and storage subsystem
> to access a CD drive.

There were a couple of versions of web-browser with OS that fit on a
1.44M floppy.

Don't forget the XDF and DMF format as well as the 2M format.

The problem with 3.5" floppies for me was the declining quality of the
media as manufacturers raced toward the bottom pricing point.

IIRC that initially, a box of 10 3.5" DSHD floppies was about $50--at
least that's what I paid for a box of Fujis back then.  None from that
original box have survived.  Initially, 3.5" DSED cost about the same.

On the other hand, I still have some of my 8" floppies from the 1970s
that are quite readable today.

--Chuck

Re: GoTEK SFR1M44-U100...

[Liam Proven via cctalk]

On Sun, 15 Jul 2018 at 06:40, Fred Cisin via cctalk
 wrote:
>
> And, in the 3.5" form factor, it was fairly straightforward to tweak the
> parameters of the format to get 1.7M on a 1.4M disk.

I did that on occasion. So did some OS distributions, just to keep the
number of boot diskettes down to just 3 and still be able to boot a
bloated 1990s OS off floppy, plus enough drivers and storage subsystem
to access a CD drive.

I always thought the WinNT installer bootstrap process was a clever
way to get around this. Boot into DOS, run WINNT.EXE and you're off.
It was much easier to get a CD working under DOS than under, say, OS/2
(swearing at the painful memories) or Linux in the early kernel-1.0
days.

I tried to explain this to an OS/2 evangelist friend of mine. He
thought I was deranged. Still, I think it would have done OS/2 a lot
of good.

> Note: to call it "1.44MB" requires creative redefining a MB to be 1024000
> bytes (10^3 * 2^10).

Once I learned this, I switched to calling them 1.4 MB floppies. This
has an added bonus: as well as feeling smugly pedantic, I infrequently
but regularly got to correct people trying to out-pedanticize me.

> There was a Barium-ferrite vertical recording 3.5" ("ED") with 2.8M
> capacity seen occasionally on IBM PS/2.  ("2.88M" in marketing megabytes,
> or 4MB unformatted capacity (which is what NeXt chose to call it))

I wish they'd caught on, if only as a bridge to...

> The "floptical" was 20MB.  Admittedly a change in technology, but the
> floptical drive could also read/write 1.4M disks.
> It was usually connected SCSI, not SA400.

I mostly saw IDE (well, ATAPI, I suspect) ones.

But they didn't stop at 20MB, of course... there were Sony HiFD and
SuperDisks. 100 MB, 120, 150, 200, 240. If the floppy diskette
industry had just kept it together, it could have kept the rewritable
CD-ROM at bay for another decade or more.

https://liam-on-linux.livejournal.com/49563.html

> There were a variety of 2.5", 2.9" drives.  Some were smaller images of
> 720K, but there was at least one with a single spiral track.

TBH I never saw much point in the (even) smaller ones.

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: GoTEK SFR1M44-U100...

[Liam Proven via cctalk]

On Sun, 15 Jul 2018 at 05:55, Grant Taylor via cctalk
 wrote:
>
> Wow.
>
> I had no idea that there was a 5¼" disk that held more than 1.2 MB.
>
> So much history that I'm sure is being lost to time.

Me neither -- and I thought I knew a fair bit about floppies. I
sometimes misstate things just in order to wind up Fred, mind you. :-)

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053

Re: GoTEK SFR1M44-U100...

[dwight via cctalk]

2.88 might be pushing the ability of a 72MHz processor. Also things like buffer 
size become an issue. For the Gotek, it is somewhat limited. One of the newer 
processors like the STM32F407, it might be possible. The Gotek uses an older 
generation processor that has limited resources. Also, the way the code is 
currently written, hard sectored is hard to do. Different encodings are not a 
big an issue as it uses transition timing and doesn't care how the data looks.

Dwight



From: cctalk  on behalf of Dave Wade via cctalk 

Sent: Sunday, July 15, 2018 1:13:20 AM
To: cctalk@classiccmp.org; 'Grant Taylor'
Subject: RE: GoTEK SFR1M44-U100...


> -Original Message-
> From: cctalk  On Behalf Of Grant Taylor via
> cctalk
> Sent: 15 July 2018 04:56
> To: cctalk@classiccmp.org
> Subject: Re: GoTEK SFR1M44-U100...
>
> On 07/14/2018 05:54 PM, Chuck Guzis via cctalk wrote:
> > There are many more forgotten floppy formats than most realize--for
> > example, the Drivetec/Kodak 5.25" 2.8MB and 6MB formats.
>
> Wow.
>
> I had no idea that there was a 5¼" disk that held more than 1.2 MB.
>
> So much history that I'm sure is being lost to time.
>

Not sure the IBM 2.44/2.88 format has been forgotten, but I would like to see a 
GoTek emulator for it..


>
>
> --
> Grant. . . .
> unix || die

Re: GoTEK SFR1M44-U100...

[Bill Gunshannon via cctalk]

On 07/13/2018 06:51 PM, Torfinn Ingolfsen via cctalk wrote:
> On Fri, Jul 13, 2018 at 11:42 PM, Chuck Guzis via cctalk
>  wrote:
>> On the other hand, if you want to use this with more general floppy
>> images, you can install the HxC firmware which supports lots of formats.
>>
> Or FlashFloppy firmware: https://github.com/keirf/FlashFloppy
> HTH

Can this be used on the device labeled SMUFDDV4@1104.

bill

RE: GoTEK SFR1M44-U100...

[Dave Wade via cctalk]

> -Original Message-
> From: cctalk  On Behalf Of Grant Taylor via
> cctalk
> Sent: 15 July 2018 04:56
> To: cctalk@classiccmp.org
> Subject: Re: GoTEK SFR1M44-U100...
> 
> On 07/14/2018 05:54 PM, Chuck Guzis via cctalk wrote:
> > There are many more forgotten floppy formats than most realize--for
> > example, the Drivetec/Kodak 5.25" 2.8MB and 6MB formats.
> 
> Wow.
> 
> I had no idea that there was a 5¼" disk that held more than 1.2 MB.
> 
> So much history that I'm sure is being lost to time.
> 

Not sure the IBM 2.44/2.88 format has been forgotten, but I would like to see a 
GoTek emulator for it..


> 
> 
> --
> Grant. . . .
> unix || die

Re: GoTEK SFR1M44-U100...

[Eric Smith via cctalk]

On Sat, Jul 14, 2018 at 10:22 PM, Chuck Guzis via cctalk <
cctalk@classiccmp.org> wrote:

> So has any of the firmware writers for the GoTek implemented the Victor
> 9000 scheme (zoned+GCR) yet?  Just curious.
>

I have a Victor 9000, so I've been meaning to add support to fluxtoimd to
be able to extract Victor 9000 data from flux transition images (DiscFerret
and KyroFlux stream file) into ImageDisk images, which are then easily
manipulated. Which reminds me, I'm way behind in merging some contributed
bug fixes.

Eric

Re: GoTEK SFR1M44-U100...

[ben via cctalk]

On 7/14/2018 6:29 PM, Chuck Guzis via cctalk wrote:

On 07/14/2018 05:05 PM, Fred Cisin via cctalk wrote:


Stringy Floppy is best forgotten.


Along with TI wafertape and similar nonsense.


I always liked the 8 track tape idea for a home brew system.
Never got around to it however.
Ben.

Re: GoTEK SFR1M44-U100...

[Fred Cisin via cctalk]

On Sat, 14 Jul 2018, Grant Taylor via cctalk wrote:

Wow.
I had no idea that there was a 5??" disk that held more than 1.2 MB.
So much history that I'm sure is being lost to time.


Just by going to 10 sectors per track (as Kaypro, Otrona, etc. did), or 
switching to 5 1024 byte sectors,  upped a 360K to 400k, or 720K to 800K.
Talltree Systems (Jlaser, etc.) peddled JFORMAT, to implement 400K on PC. 
Or, if you pushed the head past the spec'd range, to get 41 or 42 tracks, 
. . .


And, in the 3.5" form factor, it was fairly straightforward to tweak the 
parameters of the format to get 1.7M on a 1.4M disk.
Note: to call it "1.44MB" requires creative redefining a MB to be 1024000 
bytes (10^3 * 2^10).


Ensoniq Mirage, and a few others put 5 1024 byte sectors PLUS a 512 byte 
sector on each track for 880K.


There was a Barium-ferrite vertical recording 3.5" ("ED") with 2.8M 
capacity seen occasionally on IBM PS/2.  ("2.88M" in marketing megabytes, 
or 4MB unformatted capacity (which is what NeXt chose to call it))


The "floptical" was 20MB.  Admittedly a change in technology, but the 
floptical drive could also read/write 1.4M disks.

It was usually connected SCSI, not SA400.

LS120 drive also had the 1.4M capability, but the ZIP (100M, 250M?) did 
not.



And, these were just the ones that almost caught on.  At Comdex, you could 
see demos of a lot of amazing stuff that would never be seen again.


There were a variety of 2.5", 2.9" drives.  Some were smaller images of 
720K, but there was at least one with a single spiral track.


--
Grumpy Ol' Fred ci...@xenosoft.com

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/14/2018 08:56 PM, Grant Taylor via cctalk wrote:

> I had no idea that there was a 5¼" disk that held more than 1.2 MB.
> 
> So much history that I'm sure is being lost to time.


So has any of the firmware writers for the GoTek implemented the Victor
9000 scheme (zoned+GCR) yet?  Just curious.

--Chuck

Re: GoTEK SFR1M44-U100...

[Grant Taylor via cctalk]

On 07/14/2018 05:54 PM, Chuck Guzis via cctalk wrote:
There are many more forgotten floppy formats than most realize--for 
example, the Drivetec/Kodak 5.25" 2.8MB and 6MB formats.


Wow.

I had no idea that there was a 5¼" disk that held more than 1.2 MB.

So much history that I'm sure is being lost to time.



--
Grant. . . .
unix || die

Re: GoTEK SFR1M44-U100...

[dwight via cctalk]

I understand that HxC has a hard sectored working on the Gotek for H89/H8. They 
are having issues with the timing restrictions for N* hard sectored.

I've thought some about modifying a Gotek to use on my Nicolet but after some 
thought, realized it would be much easier to use something like an arduino 
directly on the I/O bus and bypass the complication of sector pulses at the 
same time as data was being transferred.

It uses 32 hard sectored disk and writes continuous data over 16 sectors. It 
looks like it can be done but it is so much simpler to just send 20 bits as 
parallel data, as one word, rather then sending FM a bit at a time.

Dwight





From: cctalk  on behalf of Chuck Guzis via 
cctalk 
Sent: Saturday, July 14, 2018 5:29:53 PM
To: Fred Cisin via cctalk
Subject: Re: GoTEK SFR1M44-U100...

On 07/14/2018 05:05 PM, Fred Cisin via cctalk wrote:

> Stringy Floppy is best forgotten.

Along with TI wafertape and similar nonsense.

Re: GoTEK SFR1M44-U100...

[Cameron Kaiser via cctalk]

> > Stringy Floppy is best forgotten.
> 
> Along with TI wafertape and similar nonsense.

I've got one of those. Fun, when it works (there's always a moment of
panic to see if it feels like working).

-- 
 personal: http://www.cameronkaiser.com/ --
  Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckai...@floodgap.com
-- Life is too short to remove USB safely. 

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/14/2018 05:05 PM, Fred Cisin via cctalk wrote:

> Stringy Floppy is best forgotten.

Along with TI wafertape and similar nonsense.

Re: GoTEK SFR1M44-U100...

[Fred Cisin via cctalk]

The floppy disk has an "index" hole and sensor.
HARD sector disks have one hole per sector.
SOFT sector disks have only one hole, and divide the track into sectors in 
software.


. . . and Apple and Commodore used soft-sectored, but do not use the index 
hole, so the track can begin at any rotational position.



Stringy Floppy is best forgotten.

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/14/2018 04:04 PM, Grant Taylor via cctalk wrote:

> It's my understanding that MS-DOS was one of the earlier OSs to
> standardize file systems used across disks for various computer
> manufacturers.  There were still some physical differences though.

Well, yes and no.  NEC really is the trailblazer here, not IBM (or for
that matter Microsoft).  The PC98 platform maintains the same format and
datarate across 8", 5.25" and 3.5" floppies, although it many cases it
can recognize and work with the IBM PC versions.   One notable aspect is
that the drives use all spin at the same 360 RPM speed.

As far as CP/M, well there is the 8" SSSD (IBM 3740) format that DRI
distributed the software on.  Various OEMs tweaked their own
interpretation of "CP/M Format, both in terms of drives and the
organization and method of storing data on them.

There are many more forgotten floppy formats than most realize--for
example, the Drivetec/Kodak 5.25" 2.8MB and 6MB formats.

--Chuck

Re: GoTEK SFR1M44-U100...

[Fred Cisin via cctalk]

On Sat, 14 Jul 2018, Grant Taylor via cctalk wrote:
I had a vague sense that different OSs had different types of floppy drives. 
I've also heard of hard vs soft sector drives, but I have no idea what the 
difference is.


The floppy disk has an "index" hole and sensor.
HARD sector disks have one hole per sector.
SOFT sector disks have only one hole, and divide the track into sectors in 
software.


I'd used CP/M at school but assumed all CP/M machines used the same disk 
format. Wrong!

*nod*
It's my understanding that MS-DOS was one of the earlier OSs to standardize 
file systems used across disks for various computer manufacturers.  There 
were still some physical differences though.


CP/M DID have a "standard format" - 8 inch Single-dided, single density.
But, when manufacturers created double sided, and double density formats, 
or used hardware that was not compatible with the "standard format", they 
each came up with different ones.  When 5.25" drives came out, each 
format was different.


I estimate that there are 2500 floppy disk formats.

I once got an opportunity to talk to Gary Kildall.  I asked him about 
creating a standard format for 5.25" CP/M.  He replied, "The standard 
format is 8 inch single sided single density."  I thought that maybe my 
request wasn't clear, and suggested that it would be helpful if there were 
also a 5.25" standard.  He reiterated, "The standard format is 8 inch 
single sided single density."  Admittedly, a single standard was simpler 
than having a single sided and a dounle sided standard, with single 
density standard, and double density standard, for each size.  (8 so far, 
and no clear end in sight.)


The IBM PC domination of the market led to all of the imitators of IBM 
being standardized.  (5.25" MFM single and double sided, 8 sectors per 
track and then 9 sectors per track.  Then "High" density 5.25" (which was 
basically similar to an 8"!).  Then "720K" 3.5".  Then "1.4M" 3.5".  Then 
"2.8M" 3.5".)


But, besides the IBM compatible MS-DOS, MANY companies had reasons for 
other formats, even with MS-DOS, as well as CP/M.


That even included a few companies who simply deliberatly wanted 
incompatability!  Intertec (Superbrain) could not grasp any reason to 
transfer files between their disks and others, other than attempts to 
STEAL their "proprietary" software! (such as PIP.COM, FORMAT.COM, . . . )
They threatened to sue me if I included their formats in XenoCopy!  That 
was the first time that I added an additional format during a tradeshow.


But, MOST incompatabilities were for perceived advantages.  Such as 800K 
GCR on Sirius/Victor-9000.  Or "quad density" 80 track formats, such as 
720K.
Or 3.5", before IBM came up with one (PC-DOS 3.20).  Companies that had 
already implemented 3.5", such as Gavilan, scrambled to change their 
formats to match IBM.

3 inch!
3.25 inch!  (Dysan bet the company on the premise that software 
availability would be the deciding factor on which "shirt-pocket" diskette 
would win out.  They created a surprisingly comprehensive publishing 
project.   Where are they NOW?)


NEC, however, made their "1.2M" format identical to their 8" format, and 
then also made their HD 3.5" identical.  (360RPM drive, instead of 
the usual 300RPM)  Although physically different, they all had the same 
layout.


--
Grumpy Ol' Fred ci...@xenosoft.com

Re: GoTEK SFR1M44-U100...

[Grant Taylor via cctalk]

On 07/14/2018 04:40 PM, Adrian Graham via cctalk wrote:
Since I got my first Gotek last year I've learned more about floppy 
drives and disks than I ever thought would be neccesary but there's SO 
many different formats out there that I never knew about.


Yep.

I expect that I will be learning things too.  In fact, I'm planing on ~> 
counting on exactly that.


Thankfully I've had some exposure through friends and various mailing 
lists; cctalk, TUHS, COFF, and various newsgroups; comp.os.vms being 
predominant.


In the 80s my exposure to floppies was all DEC so I knew about hard/soft 
sectored drives and that RX50s had to be read in an RX50 drive. PC wise 
it was all IBM-related so a disk from one machine would work in another 
(alignment issues notwithstanding).


I had a vague sense that different OSs had different types of floppy 
drives.  I've also heard of hard vs soft sector drives, but I have no 
idea what the difference is.


I'd used CP/M at school but assumed all CP/M machines used the same disk 
format. Wrong!


*nod*

It's my understanding that MS-DOS was one of the earlier OSs to 
standardize file systems used across disks for various computer 
manufacturers.  There were still some physical differences though.



Fortunately I still find learning fun :)

:-D



--
Grant. . . .
unix || die

Re: GoTEK SFR1M44-U100...

[Adrian Graham via cctalk]

>>On 07/14/2018 02:43 PM, Adrian Graham via cctalk wrote:

> I love them, I see FlashFloppy has also been mentioned which is also
> excellent. Keir Fraser (flashfloppy) is constantly updating it to add new
> support for formats suggested by folk either on the facebook group or on
> the github repository. It will support a lot of image formats natively and
> can be configured as IBM or Shugart interface though only as DS0 or DS1.
>

>*nod*

>I really like that FlashFloppy will allow the same single device to
support both 1.44 MB and 720 kB floppies.

>Aside:  I've got to say, I've never really messed with the various numbers
associated with floppy drives, but the 1536 really surprised me.

>I apparently have a lot of history to learn at some point.

Since I got my first Gotek last year I've learned more about floppy drives
and disks than I ever thought would be neccesary but there's SO many
different formats out there that I never knew about. In the 80s my exposure
to floppies was all DEC so I knew about hard/soft sectored drives and that
RX50s had to be read in an RX50 drive. PC wise it was all IBM-related so a
disk from one machine would work in another (alignment issues
notwithstanding). I'd used CP/M at school but assumed all CP/M machines
used the same disk format. Wrong!

Fortunately I still find learning fun :)

-- 
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest home computer collection?
t: @binarydinosaursf: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk

On 14 July 2018 at 22:34, Grant Taylor via cctalk 
wrote:

> On 07/14/2018 02:43 PM, Adrian Graham via cctalk wrote:
>
>> I love them, I see FlashFloppy has also been mentioned which is also
>> excellent. Keir Fraser (flashfloppy) is constantly updating it to add new
>> support for formats suggested by folk either on the facebook group or on
>> the github repository. It will support a lot of image formats natively and
>> can be configured as IBM or Shugart interface though only as DS0 or DS1.
>>
>
> *nod*
>
> I really like that FlashFloppy will allow the same single device to
> support both 1.44 MB and 720 kB floppies.
>
> Aside:  I've got to say, I've never really messed with the various numbers
> associated with floppy drives, but the 1536 really surprised me.
>
> I apparently have a lot of history to learn at some point.
>
> They've let me bring a lot of my collection back to life.
>>
>
> Yay.
>
> I'm messing with a machine that I can likely get the floppy drive to work
> (it's only 25 years old).  But I have exactly one other floppy drive and no
> floppy disks that I trust.  So I figured that I might as well convert to
> emulation and catch up with all the images that I'm using in virtualization.
>
>
>
>
> --
> Grant. . . .
> unix || die
>

Re: GoTEK SFR1M44-U100...

[Grant Taylor via cctalk]

On 07/14/2018 02:43 PM, Adrian Graham via cctalk wrote:
I love them, I see FlashFloppy has also been mentioned which is also 
excellent. Keir Fraser (flashfloppy) is constantly updating it to add new 
support for formats suggested by folk either on the facebook group or on 
the github repository. It will support a lot of image formats natively and 
can be configured as IBM or Shugart interface though only as DS0 or DS1.


*nod*

I really like that FlashFloppy will allow the same single device to 
support both 1.44 MB and 720 kB floppies.


Aside:  I've got to say, I've never really messed with the various 
numbers associated with floppy drives, but the 1536 really surprised me.


I apparently have a lot of history to learn at some point.


They've let me bring a lot of my collection back to life.


Yay.

I'm messing with a machine that I can likely get the floppy drive to 
work (it's only 25 years old).  But I have exactly one other floppy 
drive and no floppy disks that I trust.  So I figured that I might as 
well convert to emulation and catch up with all the images that I'm 
using in virtualization.




--
Grant. . . .
unix || die

Re: GoTEK SFR1M44-U100...

[Adrian Graham via cctalk]

 >>Does anyone have any experience with the GoTEK SFR1M44-U100 floppy drive
emulator that reads ""images from a USB flash drive?

I love them, I see FlashFloppy has also been mentioned which is also
excellent. Keir Fraser (flashfloppy) is constantly updating it to add new
support for formats suggested by folk either on the facebook group or on
the github repository. It will support a lot of image formats natively and
can be configured as IBM or Shugart interface though only as DS0 or DS1.

They've let me bring a lot of my collection back to life.

Cheers,

-- 
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest home computer collection?
t: @binarydinosaursf: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk

On 14 July 2018 at 18:13, Grant Taylor via cctalk 
wrote:

> On 07/13/2018 09:44 PM, Chuck Guzis via cctalk wrote:
>
>> Actually, given that allocation is in fixed units, it would be pretty
>> simple to plug in a valid partition table and dummy FAT32 filesystem image
>> with the disk space pre-allocated on the USB flash.
>>
>
> Possibly.
>
> I would want to likely use mount the discrete images as file systems
> directly.  So if they were considered partitions and had /dev entries for
> them, I could just mount them directly.
>
> In fact, one of the tricks I found was to use a special mount command that
> did that with parameters.
>
>mount -o loop,offset=$[15*1536]k,sizelimit=1440k /dev/sdb1 /mnt/tmp
>
> I've got to say that I really like the idea / knowledge that loopback
> devices can be constrained to a part of a file / device.  IMHO that could
> come in handy accessing partitions within a whole drive image (via dd).
> }:-)
>
> There are more details in a comment on the following page:
>
> Link - Review: GoTek System SFR1M44-U100K USB 1000 Floppy Disk Emulator
>  - http://goughlui.com/2013/05/19/review-gotek-system-sfr1m44-
> u100k-usb-1000-floppy-disk-emulator/
>
> But I'd look at the alternative firmware--it may well use a standard
>> filesystem scheme.
>>
>
> I am planing on trying the FlashFloppy firmware.
>
> I also ordered the OLED display.  ;-)
>
>
>
>
> --
> Grant. . . .
> unix || die
>

Re: GoTEK SFR1M44-U100...

[Grant Taylor via cctalk]

On 07/13/2018 09:44 PM, Chuck Guzis via cctalk wrote:
Actually, given that allocation is in fixed units, it would be pretty 
simple to plug in a valid partition table and dummy FAT32 filesystem 
image with the disk space pre-allocated on the USB flash.


Possibly.

I would want to likely use mount the discrete images as file systems 
directly.  So if they were considered partitions and had /dev entries 
for them, I could just mount them directly.


In fact, one of the tricks I found was to use a special mount command 
that did that with parameters.


   mount -o loop,offset=$[15*1536]k,sizelimit=1440k /dev/sdb1 /mnt/tmp

I've got to say that I really like the idea / knowledge that loopback 
devices can be constrained to a part of a file / device.  IMHO that 
could come in handy accessing partitions within a whole drive image (via 
dd).  }:-)


There are more details in a comment on the following page:

Link - Review: GoTek System SFR1M44-U100K USB 1000 Floppy Disk Emulator
 - 
http://goughlui.com/2013/05/19/review-gotek-system-sfr1m44-u100k-usb-1000-floppy-disk-emulator/


But I'd look at the alternative firmware--it may well use a standard 
filesystem scheme.


I am planing on trying the FlashFloppy firmware.

I also ordered the OLED display.  ;-)



--
Grant. . . .
unix || die

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/13/2018 07:57 PM, Grant Taylor via cctalk wrote:
> On 07/13/2018 04:13 PM, Chuck Guzis via cctalk wrote:
>> http://torlus.com/floppy/forum/viewtopic.php?t=1683
> 
> Thank you.

Please ignore my earlier non-reply--I hit the wrong button.

Actually, given that allocation is in fixed units, it would be pretty
simple to plug in a valid partition table and dummy FAT32 filesystem
image with the disk space pre-allocated on the USB flash.

But I'd look at the alternative firmware--it may well use a standard
filesystem scheme.

--Chuck

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/13/2018 07:57 PM, Grant Taylor via cctalk wrote:
> On 07/13/2018 04:13 PM, Chuck Guzis via cctalk wrote:
>> http://torlus.com/floppy/forum/viewtopic.php?t=1683
> 
> Thank you.
> 
>> In the as-provided form, it's just a bunch of sector-by-sector data
>> written to a predefined set of addresses on the flash drive.  No file
>> system at all.
> 
> Reading about the SFR1M44-U100 and the raw sector allocation made me
> think about modifying the Linux kernel for the 3rd time.  I feel like it
> should be possible to add a partitioning scheme that is the SFR1M44-U100
> layouts.  I.e. disk1 corresponds to memory address 1, disk2 corresponds
> to memory address 2, etc.
> 
> The first time was to hack the Emulex LightPulse driver to support the
> high LUN numbers of the Compaq RA-4000 & RA-4100.  The second time was
> pontificating the possibility of causing the Linux bridge code to
> forward frames that bridges are supposed to filter, to support a very
> specific use case.
> 
> 
> 


-- 
--Chuck

Sent from my digital computer

Re: GoTEK SFR1M44-U100...

[Grant Taylor via cctalk]

On 07/13/2018 04:13 PM, Chuck Guzis via cctalk wrote:

http://torlus.com/floppy/forum/viewtopic.php?t=1683


Thank you.

In the as-provided form, it's just a bunch of sector-by-sector data 
written to a predefined set of addresses on the flash drive.  No file 
system at all.


Reading about the SFR1M44-U100 and the raw sector allocation made me 
think about modifying the Linux kernel for the 3rd time.  I feel like it 
should be possible to add a partitioning scheme that is the SFR1M44-U100 
layouts.  I.e. disk1 corresponds to memory address 1, disk2 corresponds 
to memory address 2, etc.


The first time was to hack the Emulex LightPulse driver to support the 
high LUN numbers of the Compaq RA-4000 & RA-4100.  The second time was 
pontificating the possibility of causing the Linux bridge code to 
forward frames that bridges are supposed to filter, to support a very 
specific use case.




--
Grant. . . .
unix || die

Re: GoTEK SFR1M44-U100...

[Torfinn Ingolfsen via cctalk]

On Fri, Jul 13, 2018 at 11:42 PM, Chuck Guzis via cctalk
 wrote:
>
> On the other hand, if you want to use this with more general floppy
> images, you can install the HxC firmware which supports lots of formats.
>

Or FlashFloppy firmware: https://github.com/keirf/FlashFloppy
HTH
-- 
Regards,
Torfinn Ingolfsen

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/13/2018 02:50 PM, Grant Taylor via cctalk wrote:

> I was wondering what images looked like on the USB flash drive.  I found
> a couple of pages that talk about the SFR1M44-U100 using it's own
> storage format (that probably doesn't even qualify as a file system).
> I've also found tools and directions on how to work with it under Linux
> using loopback devices.

http://torlus.com/floppy/forum/viewtopic.php?t=1683

In the as-provided form, it's just a bunch of sector-by-sector data
written to a predefined set of addresses on the flash drive.  No file
system at all.

--Chuck

Re: GoTEK SFR1M44-U100...

[Grant Taylor via cctalk]

On 07/13/2018 03:42 PM, Chuck Guzis via cctalk wrote:
Yup, got a few of them here.   Depends on your needs.   If what you need 
is something that supports bog-standard 2x18x512 "1.44M" floppy images, 
it's pretty decent right out of the box.


Cool!

It uses an STM32F105 MCU and some stuff to accommodate 3.3V-to-5V 
logic shifts.


Interesting.

On the other hand, if you want to use this with more general floppy 
images, you can install the HxC firmware which supports lots of formats.


Hum.  I'll have to check that out.  Do you happen to have any links 
handy?  (I'll do a web search for it anyway.)


I was wondering what images looked like on the USB flash drive.  I found 
a couple of pages that talk about the SFR1M44-U100 using it's own 
storage format (that probably doesn't even qualify as a file system). 
I've also found tools and directions on how to work with it under Linux 
using loopback devices.


I'll check out the HxC firmware as it would be really nice if it could 
work with standard images on a file system that I can mount under Linux.


Thank you for the information Chuck.



--
Grant. . . .
unix || die

Re: GoTEK SFR1M44-U100...

[Chuck Guzis via cctalk]

On 07/13/2018 02:12 PM, Grant Taylor via cctalk wrote:
> Does anyone have any experience with the GoTEK SFR1M44-U100 floppy drive
> emulator that reads ""images from a USB flash drive?
> 
> Good?
> Bad?
> Indifferent?
> Run for the hills?

Yup, got a few of them here.   Depends on your needs.   If what you need
is something that supports bog-standard 2x18x512 "1.44M" floppy images,
it's pretty decent right out of the box.  It uses an STM32F105 MCU and
some stuff to accommodate 3.3V-to-5V logic shifts.

On the other hand, if you want to use this with more general floppy
images, you can install the HxC firmware which supports lots of formats.

--Chuck

GoTEK SFR1M44-U100...

[Grant Taylor via cctalk]

Does anyone have any experience with the GoTEK SFR1M44-U100 floppy drive 
emulator that reads ""images from a USB flash drive?


Good?
Bad?
Indifferent?
Run for the hills?



--
Grant. . . .
unix || die