Sheesh, Don - have mercy!
I'll send you the ROM Real Soon Now (tm).
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Just kidding. I don't really need the physical PROM, just the 64W octal image dump would do, if you can put in in an M9312 and use ODT to dump the bits.
Otherwise I can read the physical prom as a hex file and disassemble the bits back to source (I wrote some tools to do that for all the other PROM images).
Don
As an aside, I suspect it is similar to the MSCP DU boot prom, but I tried writing an MU version based on documentation, and just could not get it to fit in 64W.
So I am technically interested in what shortcut(s) DEC could take to get the MSCP command sequence for booting from an MU device.
There may just be some magic pattern you shove into a register to make it happen. Just guessing. IDK.
Not to worry - no offense taken. I don't have anything to run it in or read it on, but I'll send the board off to you this week.
Some rumor had it that you wrote a magic sequence into the CSR for the TMSCP, yes. A vague memory of mine is that it was the word for "MU". But that is all hearsay. I have never seen the actual rom.
And I know that others have also tried and failed to get the code to fit in 64 words.![]()
Hi all,
UniBone emulates now the M9312 bootstrap ROM card.
Each of the 5 ROMs can be loaded with MACRO11 listings files from
http://www.ak6dn.com/PDP-11/M9312/
The tricky bootvector redirection logic is also implemented.
The address to execute after power-on is given as symbolic MACRO11 label.
For demonstration the script "m9312+xxdp_dl0.sh" is given,
which boots into 11/34 console emulator, or auto-boots XXDP from RL02.
kind regards,
Joerg
Wow, Joerg! This is great! And barely over a month since my inquiry on the UniBone group. Talk about Ask and ye shall receive!
Now if only snail mail would hurry up and deliver my UniBone to me.
Thanks for making this happen.
--Jay
Thanks Jack!
I got the board today, pulled the MU boot prom, read it, and converted it back to source/listing/hex file for the device.
The results have been uploaded to my site: https://www.ak6dn.com/PDP-11/M9312/ and are under the 23-E39A9 'MU' boot device entry.
Surprisingly (or maybe not) there is no magic sequence or anything like that. Basic TMSCP commands but not as complete as most toggle-in bootstraps. Ie, there is no 'rewind' command given, just go ONLINE and READ blocks. So this boot PROM is not quite as robust as is, for example, the SIMH boot code for MU.
Don
And FYI if anyone needs any device boot PROMs I have blank NOS devices where I can program any device from my website using an EEtools TopMaxII programmer.
Also have lots of the common devices (DL, DY, etc) from DEC boards available. Nominal cost of $5 per device plus shipping for anyone interested.
Interesting. So the rumors were all false.
And actually, an MU prom could be rather useful for Update's PDP-11/70, which nowadays only have a TU81 connected. We do have a TU77 around, but it would require some work to get it in order. And I do worry that an accident would happen that would require me to recover the system without a working disk...
But already just having the code makes it much easier to do a recovery through the front panel to start with.
But maybe I should ping you offline...
An additional FYI I found actual 23-E32A9/23-E33A9 'XE' DELUA/DEUNA net boot devices that I had previously acquired (and misfiled).
I read these and converted to source/listings/hex files are they are now up on the website under: https://www.ak6dn.com/PDP-11/M9312/
Don
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