Re: Possible PUTR bug?
I wish that I were to have met you 40 years ago! Learning that stuff by error, error, error, trial, and error was inefficient. -- Grumpy Ol' Fred ci...@xenosoft.com On Sat, 11 May 2019, allison via cctech wrote: My Solution is easier, least for me. I have a few Z80 CP/M machines with 765A in it and if it can't read it its likely due to being hard sectored or M2FM. I has 3.6, 5.25 and 8" and the 5.25 are Teac FD55gfh which are dual speed and can do all modes. With my own software and utilities it does whatever even RX180, RX50, RX33, and RX22/23 formats from the DEC pool. The PC machine for when that stuff is needed is a DELL pizza box that has 32mb of ram and 486dx/66 (ISA/ISA16) and can run dos though NT4 as needed as I have a buttload of ST3660As as media for them (have two as a spare). That machine uses a combo IO controller for the FDC seems to do what I ask of it. Also an old Compag with similar features and PII and 32MB and also does Ethernet but the disk controller is a newer ISA16 using a combo chip and most of the combo chips after late 90s-ish seem to have an even shorter VFO sync window (flash blindess). I neither expect nor desire modern machine with anything past NT4 to behave well with old disks. Though Mini-ITX boards all seem to support everything and anything and have all the legacy ports. They all run linux and if needed a partition (60mb of disk is trivial) for MSdos 6.22 or freedos. Oh, unless its under threat the OS is linux, freedos, or if required XP Though the latter is usually under VMware or Virtualbox on Linux.. I just got tired of all the winders hassles and requirements for insane hardware needs every few years. Most stuff runs fine under dosemu or wine. As to RT11, I have run mostly V5.0x and as needed if a device required it a later driver borrowed from V5.04 or later. It just seems to work with out much pain. As to running a RX50 on a PC... That drive was a neat thing but its mostly the interface is incompatible with most standard floppies and a FD55A/B or any of the 48tpi 40 track drives will read and write the media. I make a point of only using it on PDP-11 as transfer media, its low density so its marginal for much. Keep in mine that drive select is used to select the A or B drive of a RX50 there is no side. They had a terrible track record for reliability. I can put Two RX33 [teac fd55gfh] in the same space and store more. Some to think of it most Late PC 5.25 and 3.5 inch drives are incompatable with old standard [TM100 and that era] as many do not have a 1 of 4 drive select jumper and use the funky PC only twist cable. I neatly sidestep all of the cruft and hacks needed for super wizbang winXP and later machines. I figure if I'm going to play with old hardware I need to retain the old hardware to maintain them. So I retained the best of the best old PCs as they bulk of them are crap. I buy new hardware that is not neutered. Mini/Micro-ITX board with atom or celeron CPUs (really all that's needed) are cheap and easily built up into linux boxes or if you must any of the older 32 bit winders incantations. Allison
Re: Possible PUTR bug?
My Solution is easier, least for me. I have a few Z80 CP/M machines with 765A in it and if it can't read it its likely due to being hard sectored or M2FM. I has 3.6, 5.25 and 8" and the 5.25 are Teac FD55gfh which are dual speed and can do all modes. With my own software and utilities it does whatever even RX180, RX50, RX33, and RX22/23 formats from the DEC pool. The PC machine for when that stuff is needed is a DELL pizza box that has 32mb of ram and 486dx/66 (ISA/ISA16) and can run dos though NT4 as needed as I have a buttload of ST3660As as media for them (have two as a spare). That machine uses a combo IO controller for the FDC seems to do what I ask of it. Also an old Compag with similar features and PII and 32MB and also does Ethernet but the disk controller is a newer ISA16 using a combo chip and most of the combo chips after late 90s-ish seem to have an even shorter VFO sync window (flash blindess). I neither expect nor desire modern machine with anything past NT4 to behave well with old disks. Though Mini-ITX boards all seem to support everything and anything and have all the legacy ports. They all run linux and if needed a partition (60mb of disk is trivial) for MSdos 6.22 or freedos. Oh, unless its under threat the OS is linux, freedos, or if required XP Though the latter is usually under VMware or Virtualbox on Linux.. I just got tired of all the winders hassles and requirements for insane hardware needs every few years. Most stuff runs fine under dosemu or wine. As to RT11, I have run mostly V5.0x and as needed if a device required it a later driver borrowed from V5.04 or later. It just seems to work with out much pain. As to running a RX50 on a PC... That drive was a neat thing but its mostly the interface is incompatible with most standard floppies and a FD55A/B or any of the 48tpi 40 track drives will read and write the media. I make a point of only using it on PDP-11 as transfer media, its low density so its marginal for much. Keep in mine that drive select is used to select the A or B drive of a RX50 there is no side. They had a terrible track record for reliability. I can put Two RX33 [teac fd55gfh] in the same space and store more. Some to think of it most Late PC 5.25 and 3.5 inch drives are incompatable with old standard [TM100 and that era] as many do not have a 1 of 4 drive select jumper and use the funky PC only twist cable. I neatly sidestep all of the cruft and hacks needed for super wizbang winXP and later machines. I figure if I'm going to play with old hardware I need to retain the old hardware to maintain them. So I retained the best of the best old PCs as they bulk of them are crap. I buy new hardware that is not neutered. Mini/Micro-ITX board with atom or celeron CPUs (really all that's needed) are cheap and easily built up into linux boxes or if you must any of the older 32 bit winders incantations. Allison ]On 05/11/2019 11:22 AM, Douglas Taylor via cctech wrote: > I understand your frustration, because all I really wanted to do was > read/write RX33 and RX50 5-1/4" floppies to move data in and out of my > microPDP11. Once, I wanted to write an RX23 3-1/2" floppy with OpenVMS > PAK files that could be read on an DEC Alpha. > > Finding a PC that supports the 5-1/4" floppy drive is difficult, the > BIOS or FDC chips only support 3-1/2" floppies in many late model PC's. > It appeared only a few of the older PC's that supported the 5-1/4" > drives could actually change the spindle speed so you could read/write > RX50 format. > > I dedicated a DELL XPS 233H to this task, 32MB memory, Pentium II cpu. > Boots from 3GB hard disk, DOS and Win 3.1 (if you so need it). I also > have an IDE to CF card adapter standing by when the hard disk dies. > Love to have something with a smaller form factor, but it gets the job > done. > > Doug > > > On 5/11/2019 10:35 AM, Charles via cctalk wrote: >> Just an update... I spent an entire long afternoon wrestling with that >> old PC, trying to find some combination of HDD jumpers and BIOS >> settings that would allow the XP hard drive to boot with another drive >> attached (either on the slave connector or the secondary channel with >> the CD-ROM removed). No dice. >> >> So I had the bright idea to use Minitool's Partition Wizard, and >> shrink my Windows partition so there'd be room for a newDOS partition. >> But it won't even run (probably because I have only 64 MB RAM on that >> box). Grrr. It's unbelievably slow anyhow, so more SDRAM on order, >> which is really cheap these days. >> I'd get a newer PC for the workbench, but need to keep the old >> motherboard because there are a couple of devices (including a PB-10 >> PROM programmer) which are ISA slots. >> >> So, this has become a Windows/PC (ugh) project instead of just being >> able to play with my PDP-11... >> >
Re: PDP-11/40 available, Arizona
On 5/10/19 6:42 PM, Adam Thornton via cctech wrote: I have been invited out to the site tomorrow morning to take an inventory of what’s there (I live near the machines). I imagine that I may well have a lot of photos that I bring to the list and say “what is this?” Standing by to help out! Go get it, Adam -- (come on, you can _make_ room! :-))
RE: HP 1000 A900 ("Magic") Questions
>-Original Message-
>From: cctech [mailto:cctech-boun...@classiccmp.org] On Behalf Of Glen Slick
>via cctech
>Sent: Friday, May 10, 2019 1:34 PM
>To: General Discussion: On-Topic Posts
>Subject: Re: HP 1000 A900 ("Magic") Questions
>
>On Fri, May 10, 2019 at 4:14 AM Paul Birkel via cctech
> wrote:
>>
>> Aficionados;
>>
>> I'm interested in acquiring an HP1000 A900, in any form-factor.
>> (http://www.hpmuseum.net/display_item.php?hw=594)
>Another hard part is the 1 memory frontplane. Maybe it wouldn't be
>too hard to build an equivalent PCB if the proper connectors can be
>acquired. They are 3-row 96-pin connectors. Maybe common DIN 41612
>connectors would work, I haven't looked at that closely.
I can confirm that DIN 41612 connectors should work fine, along with a 4-layer
PCB. HP doesn't seem to have gone "odd-ball" in that particular design choice.
I'd need to get someone to buzz out the connections to ensure that they are
1:1 all the way across before designing a PCB to fit.
>At a minimum you need either a 12005 serial card or a 12040 serial mux
>for a console interface. Both of those are fairly common, although you
>might pay more for cables than the boards if you don't build cables
>yourself. There are several firmware versions for the 12040 mux. If
>you have a D mux you need need VCP firmware 4020 or higher on the
>12203A cache controller.
Cables, and those specialized HP connectors, are always a pain. I would need
to make up my own, given my budget, I expect. I do have one or two possible
spares from a 21MX I/O environment that probably could be repurposed assuming
that the edge-connectors match up ... which they may not. We'll see. Thanks
for the notes about the firmware version issue.
>As you also said you need a 12009 HPIB card for a storage interface.
>Running HPDrive on a PC to emulate disk and tape drives works well if
>you don't have any real HPIB disk and tape drives. I managed to pick
>up a 12016 SCSI card. Those are rare and expensive.
I'll bet! Yes, I was assuming that HPDrive would be the way to proceed; it's
good to get confirmation on that point. Also the availability of a suitably
configured RTE.
paul
