10 Feb
2022
10 Feb
'22
4:05 p.m.
Looking at my inventory, I seem to have no less than four spare M8266
(plus one in my 11/34 that runs, plus probably another in my 11/34 out
in the garage.)
Rod, where are you located?
JRJ
On 2/9/2022 6:16 PM, Rod Smallwood via cctalk wrote:
Hi
??? We have narrowed the problem down.
Its the instruction decode ROM's that are the issue.
The images of those are whats needed.
Regards Rod
On 09/02/2022 23:14, Sytse van Slooten via cctalk wrote:
>>>> On Tue, Feb 8, 2022 at 7:04 PM Warner Losh <imp at bsdimp.com>
wrote:
>>>> I found
>>>>
https://deramp.com/downloads/mfe_archive/011-Digital%20Equipment%20Corporat…
>>>>
>>>> which has the source code...
>>>>
>>>> But I couldn't find the tools to use these files to create microcode
>>>> images.
>> Actually, the "m8266_ucode.v.txt" there seems to actually be the
>> program that
>> produced the symbolic dump (which is also available at:
>>
>> ? http://www.bitsavers.org/pdf/dec/pdp11/1134/m8266_ucode.out.txt)
>>
>> It looks like the program is in VHDL or something like that, but it
>> doesn't
>> seem to have the actual microcode (was it stored/defined in another VHDL
>> file?); that raises the question of where the actual microcode that
>> it was
>> dumping was.
> It's Verilog (the 'other' hardware language besides VHDL), and indeed
> the rom images are in other files/modules - in some kind of straight
> binary format, I'd guess.
>
> I'm properly intrigued why someone would choose to do this - which
> seems to be mostly listing the microcode in a readable format - in
> Verilog. Unless of course it would be with a long term goal of using
> that microcode in an emulator that is sufficiently like a 'real' 11/34
> to run it unchanged. I wonder if that is the case, and what became of
> the project - since the files are from 2014, it's probably safe to
> assume it got stuck somewhere along the way.
>
> Somewhere way down on my list of things to explore is something
> similar but then for the 11/70 - to make a vhdl version that is
> microcode compatible with the original, unlike the current pdp2011
> that's 'only' functionally compatible. And this is about exactly the
> same way I would start - except I don't have the '70 rom images yet...
> If anyone has them and is willing to share, drop me a note ;-)
>
> Cheers
> Sytse
>
>