December 2023 - cctalk - classiccmp.org

imd2raw.c correction - linearizing ImageDisk images

by David Schmidt

There have been a few versions of the utility imd2raw.c floating around that will take Dave Dunfield's ImageDisk-created images (i.e. an .IMD file) and make a linear binary image devoid of any metadata. This is similar to the function of Dave's IMDU.COM program's /b switch. I've corrected a problem with the assumption that all imd2raw.c descendants to date have made: sectors that have a skew (i.e. not 1-1 interleaved) weren't linearized correctly. The skewed sectors need to be written out in "sorted" order, which is not necessarily captured/physical order. This is easily verified by comparing output from "IMDU /b" to earlier imd2raw outputs on any .IMD that has a sector skew that isn't 1, 2, 3 [...]. It's up on github here: https://github.com/RetroFloppy/imd2raw

1 week, 5 days

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NRAO Data tapes

by Dani Werts

Hello, I'm an employee with the National radio astronomy observatory here in Socorro New Mexico. As part of our NGVLA upgrades, we are seeking to get rid of old data tapes from the tape reel days of Computing. These contain things such as the boot loaders, OS, specific collection programs and antenna movement programs. I personally would hate to see these just wind up in the literal dumpster and would like to see them sent out to a museum or an archiving body that can preserve them and keep them safe as a dynamic part of history. If anyone is interested or knows someone who would be interested in the VLAs data tape library please let me know. V/R Danielle Werts Front end engineer VLA Socorro New Mexico

5 months, 1 week

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FTGH: (3) Qualstar 1260 9 track tape drives pertec interface

by js＠cimmeri.com

2 units working when properly stored a few years ago. 1 unit, parts unit. Must take all 3. Tested successfully only with a PC and a VAX. Located in Frederick, Maryland, USA

2 years, 5 months

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11/15, 11/20 systems and parts, more

by Paul Anderson

I am working on a deal which includes several PDP11/15 or 20s. I will be looking at them next week and hope to get more details. I will look for exact model numbers and configuration.At least 2 of them have non DEC silkscreens on the front panel. Also a selection of 11/05 and 11/10 including 5 1/4 box, BA11-D, and BA11-K units. If you are interested in a box or parts please email me off list. Thanks, Paul

2 years, 6 months

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86-DOS disks...

by geneb

For those interested, I've imaged a couple of super rare (actually rare, not "ebay" rare) original 86-DOS disks. https://archive.org/details/86-dos-version-0.1-c-serial-11-original-disk https://archive.org/details/86-dos-version-0.34-c-serial-221-original-disk Both will boot under simh. g. -- Proud owner of F-15C 80-0007 http://www.f15sim.com - The only one of its kind. http://www.diy-cockpits.org/coll - Go Collimated or Go Home. Some people collect things for a hobby. Geeks collect hobbies. ScarletDME - The red hot Data Management Environment A Multi-Value database for the masses, not the classes. http://scarlet.deltasoft.com - Get it _today_!

2 years, 6 months

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Anyone have a D1 deck?

by Jim Brain

https://entertainment.slashdot.org/story/23/12/30/0151241/documentarians-se… -- Jim Brain brain(a)jbrain.com www.jbrain.com

2 years, 6 months

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Axil 220/245 PSU

by Alan Perry

Does anyone here have a running Axil 220 or 245 (Sun SPARCstation LX clone)? My 220 has a dead PSU and I am trying to get it working with a modern PC PSU. But I don’t know the pinout for the power connector. While the power connector is the same as used by Sun, the pinout and, aside from +5V and GND, the wire color scheme are different. I have identified 3 of the 6 wire colors and 7 of the 10 pins. The wire color scheme seemed to be a match for early sun4c but I just found something that suggests a couple wire colors are used differently. I have found that black is ground, red is +5V, and yellow is +12V. White, orange, and blue are TBD. A marking on the PSU board suggests white is -12V. Blue and orange seem to only used by a daughter board centered on a LM339 chip. But, as a software guy, I can’t tell what it does. Anyone here have any insight here that might help me? alan

2 years, 7 months

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Re: Computhink Eagle 32 - software, docs, info?

by Chris Hanson

I picked up this system from its previous caretaker yesterday, to hold onto for a friend. I’ve also inventoried the major functional ICs and archived the “IPL-M” ROMs. Here’s what’s in the Eagle-32: - Main Logic Board - 8MHz 68000 CPU - 2x D8255 programmable peripheral interface - left 8255 is clearly for parallel and user port - right 8255 I strongly suspect is for hard disk, possibly ANSI or SASI - D8253C programmable interval timer - 2x 2651N programmable communications interface for serial ports - 2x 2716 for IPL-M 0/1 ROMs - Disk Controller Board - FD1701B-02 floppy disk controller - No video board, whether text or graphics Since there’s no video board in the system, and a couple of cables internally that aren’t attached to anything, I expect it was removed by a previous caretaker. This is sad because without one it’s unlikely to come up, not that anyone has found any software for it. On the other hand, there are zero PALs, so both full reverse engineering and maintenance should be straightforward. I threw the 4KB of boot ROM in Ghidra and confirmed a couple things: - At boot, ROM is mapped to 0, and then remapped either by a write to the location or by a cycle counter: The initial stack pointer at 0x0 is 0x0001fffe and the initial program counter at 0x4 is 0x00ffc026, indicating the ROM is normally located at 0x00ffc000. - The ROM freely interchanges addresses in the 0x00ffc000..0x00ffffff range and addresses in the 0xffffc000..0xffffffff range, which is annoying to deal with in Ghidra. - I/O devices appear to be in the 0x00ff8000..0x00ffbfff range, all of the devices accessed via the bootstrap seem to be barely above 0x00ff8000. - Only NMI, bus error, interrupt 2, and interrupt 5 are set up by the bootstrap. - The bootstrap is very bare-bones but still has a bunch of indirection in it; it’s obviously written in assembly, but it does seem to have parameterization so it may support both console and serial I/O. I suspect that I can figure out from the pattern of I/O accesses which devices are at which address in the memory map, at least if I bring up an emulation in MAME. That should at least allow writing new code for it, and _maybe_ even figuring out which CRT controller the video hardware uses and where in the memory map it is. (I suspect the 6845 and/or 6847 just from the time period, but who knows? Gotta see what it actually do when trying to show the “IPL IN PROGRESS” string contained in the ROM, or one of the couple error strings…) — Chris

2 years, 7 months

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qbert license?

by Steve Lewis

Perhaps slightly off topic, but perhaps someone here has a contact or idea on how to get started on this: Someone has done a Q-Bert port in 2023 to a new system. The title is different, but the "look and feel" (and audio) is pretty "authentic" to the original (not sure if using exactly the same original tiles and such, I believe it was all original work - but still, it's very much an arcade-style clone). We see now that Sony "owns" it these days (I seem to remember decades ago there a Q-bert cartoon? But perhaps remembering it wrong). The question is, how would one start on obtaining a license? I assume it wouldn't be cost effective (for a free casual port), but still just curious. I've tried to contact Sony in the past (on a different software title), but it's just a huge enterprise it's a bit challenging to approach. Just wondering on the off chance if maybe someone around here has gone down this road already? -Steve

2 years, 7 months

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RSTS/E questions.

by Bill Gunshannon

I am back to playing with RSTS/E 10.1 again and have a couple questions if there is still anyone around with experience. First: Is there a way to change the allowed length for passwords? Second: Is there a way to make login take the assigned name rather than the x,x format for logins? I seem to remember using a system once that did but I have no idea if it was legit or a local hack. Although I have no problem using local hacks. :-) Need to get a system going and maybe even join HECNET. I really wish there was TCP/IP for RSTS. bill

2 years, 7 months

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cctalk December 2023