From: Johnny
Billquist bqt at update.uu.se
The per-device code are in separate PROMs that
are used in both the
9301 and 9312. Those are the ones with the device code as constants
in
the beginning of memory space for the PROM, by
the way.
As I mentioned, the M9301-YA, at least, does not have this code. (See the
listing.) Also, again on the M9301-YA, the various bootstraps, diagnostics,
and console, are scattered through both banks (ditto), so one can't just
replace a PROM or two to chance the supported devices; one would have to
replace the entire set of 4 PROMs.
I hope you also are aware that both the M9301 and
the M9312 have
different boot roms for some machines. I know that the 11/70 use
different roms with other tests than other PDP-11s, and I seem to
remember that one or two others do as well. (The 11/60 keeps popping
up
in my brain...)
I have yet to investigate the M9312's in depth, but I did know there are
quite
a few different versions of the M9301 (which amount to different ROMs: I
know
there are two different etch revisions of the card itself, but I think they
are programming-wise identical). I don't know of any good list of the
variants, but here are the versions I know of (device codes abbreviated to
save typing):
M9301-YA /04 and /34 OEM version; has basic diagnostics, console
emulator,
boots from various devices (RK, RP, TC, TM, DL, PC, TA,
RX),
supports auto-boot on power on, and also power-fail restart
M9301-YB /04 and /34 end user version; has basic diagnostics,
console emulator,
boots from various devices (RK, RP, TC, TM, TA, RX, DL, PC,
RJS, RJP, TJU), also power-fail restart
M9301-YC /70 version; contains basic CPU, cache and memory
diagnostics,
boots from various devices (TM, TC, RK, RP, RK06, RJS,
RJP, TJU, RX)
M9301-YD All models; contains code to allow a terminal attached to
the
machine to be a terminal on some other line; also has boot
code for RX and DDCMP
M9301-YE All models; has basic diagnostics, console emulator; boots
from low speed paper tape or DECnet; supports auto-boot on
power on, and also power-fail restart
M9301-YF All models (auto-start not available on /45, /50); has
basic
diagnostics, console emulator, boots from various devices
(RK, RK06, RP, TC, TM, TA, RX, DL, PC, RJS, RJP, TJU)
supports auto-boot on power on, and also power-fail restart
M9301-YH /60 and /70 version; contains basic CPU, cache and memory
diagnostics,
boots from various devices (TM, TC, RK, RP, RK06, RJS,
RJP, TJU, RX, PC)
M9301-YH All models; has basic diagnostics, console emulator; boots
from DECnet, and various devices (RX, TU, DL, DMC), also
power-fail restart
The -YA is the only one I have examined in detail.
Noel
I know this is more than half a year ago but I just recently dumped the
contents of the M9301-YB if someone is interested or like to archive it
somewhere.
and did some initial checking of the code. It is fairly similar to the
disassembly that Noel Chiappa has provided earlier, although the different
routines are arranged in completely new way.
/Mattis