I seen a video on youtube the other night by usagi electric about getting a MicroPDP 11/83 running again and it appeared when he booted it it had a program run even though he had no storage hooked up, I am thinking it was a monitor on a rom, it looked like the vax rom you can get on boot up with >>> where you would pass b dua0 or whatnot, I didn’t think PDP11’s had those though I never have personally owned a PDP11. I was curious it it would be xxdp built into a rom or maybe a bootstrap card like a M9312? I play around in simh with the PDP11s and wanted to try to load up whatever rom that was but I don’t know exactly what I am searching for and so far the rom’s I’ve tried have done nothing upon booting. Any ideas?
He may have digital tape cassette rather a regular floppy or HD.
http://sparetimegizmos.com/Hardware/TU58_Emulator.htm
I haven’t seen this particular video, but PDP-11 bootstrap ROMs on the post-blinkenlights machines (and retro-fitted to most of the blinkenlights machines) contain a piece of software called the On-line Debugging Tool, or ODT. (It would indeed be on the m9312, as you mention, for the Unibus machines.) It provides basic monitor services (deposit a word into RAM, examine a word of RAM, jump to an instruction in RAM). It typically also provides a very brief POST-style diagnostic, and can have up to two boot ROMs fitted. These boot ROMs vary in capability, but can generally boot from the DEC-defined boot sector of various hardware devices (for example, block 0 of a disk or DECTape).
Is it this video?
There’s an Australian retro forum which has some experience with the same kit:
Thank you all for your replies, the video shows exactly the screen I seen in the other video, I’m going to give a try with the tu emulator, ODT if I can find it and the disks they linked from that mpdp rebuild you linked.
There are two parts in this; the ODT is part of the micro-code of the LSI processors. The boot ROMs are on some board (can be processor board, like the M8189 in the PDP-11/23+ or another board, like the BDV11/M8012). These ROMs contain boot routines for various tapes and disks and RAM tests. Very useful!
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Useful, but at a price. DEC never sold a personal PDP 11 so configuration of any of PDP 11 systems is always a black art for the average Joe, who does not have that knowledge. The Heathkit 11 came only in one flavor. With bitsavers things are a bit better, but Unix quote “You are Not Expected to Understand This” still applies.
DEC did have the DEC Pro 350 series. Which was pretty much a PDP-11 personal workstation.