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Hi all, I'd like to see if anyone has ever dumped the PROMs on the PDP-11/70's M8123 RAC card. I've started the laborious process of transcribing the microcode firmware as listed in the M8123 engineering drawings (drawing number D-CS-M8123-0-1), but this is obviously tedious and error prone...

Hi all, I recently completed writing a DMD 5620 Terminal Emulator. This was the commercial version of the "Blit" or "jerq" terminal developed at AT&T Bell Labs for use with UNIX systems. I hope it's not too off-topic for this forum! Of course, to really get the best functionality out of it...

Hi all, I have just been given my dream setup - a number of AT&T 3B2/600G systems, peripherals, spares, and manuals. Over all, I'm going to guess this is one to two shipping pallets worth of stuff. The only problem is that it's all in Virginia, and I'm near Seattle, WA. I know I'm going to need...

This weekend I picked up a VT52 DECscope terminal from a fellow collector. It's in fantastic shape, apart from being a little dirty and missing the number "6" keycap from the number pad. This is a real long shot, but if you have a permanently broken VT52 terminal you're keeping for parts, could...

I just noticed my fans going crazy while reading the forum, and then Symantec popped up this warning: I'm not sure how it got here, but just a warning: Someone is mining cryptocurrency by inserting some random JavaScript into the forum, somewhere. -Twylo

Hi folks, I just wanted to post a quick note here that the SIMH AT&T 3B2 Emulator I've been working on for ages is finally ready for real users now. There are still a few things broken, but for the most part it seems to work pretty well. I've put up some documentation about how to get...

Hi all, Yesterday I picked up a couple of free DECstation 5000/133s. Upon inspection when I got them home on my bench, one power supply was dead, the other seemed OK, but failed almost immediately. The failure mode was completely non-spectacular. No blown caps, no blown fuses, the fans just...

Yes, I'm still working on it! Thanks to the gift of an anonymous donor, I have access to the 3B2 Off-Line Diagnostics manual, and that has helped me fix numerous bugs. The "Off-Line Diagnostics" referred to in the manual are the Debug Monitor (DGMON) tests available on the "3B2 Maintenance...

It's been about a year since I last asked around, so it's that time again! Time for me to beg, on bended knee, for any and all documentation that might exist about the AT&T 3B2 architecture and internals. My 3B2 emulator sits unfinished, and likely will remain unfinished until I have access to...

Hi folks, Just a general update, I'm still working on my AT&T 3B2 emulator based on the SIMH platform. It lay dormant for almost a year while I was dealing with life matters, but I've recently dived back in with a vengeance. I'm still desperately seeking any documentation or schematics that...

Hi folks, This is as always a tremendous long shot, but I figured I would put it out there anyway...

This TD Systems TDL-11 card came with the DEC stuff that I picked up last weekend. I can't find a single reference to the TDL-11 on the Internet, but there are references to the TDL-12, which apparently was much more common. The TDL-12 pretended to be an RLV-12 controller and mapped virtual...

Last week, I scored a big pile of free DEC gear, including a couple of MicroPDP-11's and about 6 RD52 drives, woo-hoo! Bad news: all the RD52 disks but two had been wiped clean some time in the early 2000s. They all have nearly empty RT11SJ installs with little more than DIR.SAV on them. Worse...

Hey all, I just wanted to share an update on the current status of my 3B2 emulator. I've been making a lot of good progress. I have enough of a WE32100 CPU core built to run the 3B2 firmware. It passes power-on self tests, and can run the built in firmware mode programs (like "version" and...

Hey folks, I've started down the path of implementing an AT&T 3B2 simulator using the SIMH platform. Key to doing this will be access to 3B2 ROMs and technical information, both of which have proven very difficult to get ahold of. Right now I'm working from the 3B2 information publicly...

Hi folks, Alright, I know the MPS-803 is (putting it nicely) a terrible, terrible printer. But it's also nostalgic for me, because that's the printer I had with my C64 growing up. That said, I have an MPS-803 that used to work fine until I moved houses. I've just set it up for the first time...

Hey all, One of my projects yesterday was to finally fix the power supply in my Heathkit H89 CP/M computer. It's back up and running now, but I haven't got ANY media for it, so I'm basically stuck with an "H:" prompt and not much else to do with it. Here's my very, very dumb question for you...

Hi all, I recently bought a TRS-80 model 4 at a flea market. After cleaning it up and repairing the power supply (it had a bad solder joint on the +12V line, which I understand is pretty common) it's in good working shape again. But, I haven't got any disks for it. None at all. Is there a...

I just picked up a Packard Bell Pack-Mate PB800. It's got the following specs: 80286 CPU 1MB RAM C&T CS8221 Chipset Phoenix BIOS WD1003V-MM2 MFM Controller I was hoping to use this box as a general-purpose MFM drive tester and formatter, but I can't seem to find the Winchester controller...

Hey folks, Two weekends ago I was at a local swap meet when a beige box caught my eye. It turns out to have been a Pro 350 in a pedestal stand that looked like it had been dropped off a truck two or three time -- dirty, covered in thick dirt, and badly cracked. Amazingly, once I got the broken...