[Simh] vmb.exe - info - source code ? / vax (no O.S.) disk programming

[Johnny Billquist]

On 2020-05-12 16:23, Mike Stramba wrote:
> What is the "story"  with vmb.exe ?
> 
> Is there source code for it ?
> 
> If not, why not ?

VMB is the boot firmware for VAXen. For some models it is loaded from 
disk, for most it's in EEPROM or flash storage on the machine.

Source code was never, as far as I know, made available. It's just a 
boot loader. Noone ever modified it, or had use for it in any other 
context than on a VAX in the first place, and it already was on the VAX. 
So nobody really felt even a need...

> Is it "abandon ware" ?

Not really. It's owned by HP.

> I'm interested in seeing how it  does  "raw disk" access.

Uh? Why? Do you expect it to do something particular that any OS 
wouldn't? I haven't got a proper clue, but I would also suspect it's 
either written in MACRO-32 or Bliss. You like reading that?

> I have MSCP Basic Disk Functions Manual AA-L619A-TK Version 1.2 and
> EK-UDA50-UG-002_UDA50_Users_Guide_Oct82.pdf
> 
> Are there any other relevant docs ?

If you want to know how to talk MSCP, why don't you just look at the 
device drivers for NetBSD or something? You already have the code there, 
which in combination with the documents you possess should be more than 
enough, and then you'll have code in C, which might be easier to read...

   Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol