On Dec 12, 11:27, John Allain wrote:
> >> Jerome Fine replies:
> >>
> >> First, the M8190-AB is a PDP-11/73 CPU board and
> >> usually runs in an ALL Qbus system. Don't forget that
>
> > Patrick Finnegan answers:
> > So can someone fix this in the "FIELD GUIDE TO Q-BUS
> > AND UNIBUS MODULES"
> > doc? It's got an M8190 listed as an 11/84 CPU.
>
> In another source
> KDJ11-A_UsersManual.pdf. page.73/2-18,
> the M8192 is the J11, which is the 11/73 CPU.
Not necessariliy, or to put it another way, both are correct. The J11
is a chip , used in several PDP-11 variants.
The M8190 is a processor board used in 11/73, 11/83, and 11/84. The
difference is (1) the 11/73 originally had a 15MHz clock, and the 11/83
and 11/84 had an 18MHz clock, (2) the 11/73 and 11/8x had different
ROMs, and (3) in an 11/73 system the memory is arranged after the CPU
in conventional fashion, whereas in an 11/83 the memory is PMI memory
and is placed before the CPU. There are several revisions of the ROMs
for the 11/8x, and the second letter of the suffix (the first is always
'B') tells you what the original ROM version was. This is a
quad-height board with two bootstrap ROMs (actually EPROMs), line time
clock, and two SLUs. All M8190s are the same (modulo engineering
change orders etc) apart from crystal and ROMs.
The M8192 is always an 11/73; it's a dual-height board with no SLus or
ROMs, etc. It was usually sold as an OEM item or as an upgrade for
11/23 systems. There ar a few variants of this too, becasue there as a
bug in early versions of an ASIC which meant that some early ones would
not work with an FPU upgrade.
All these boards are Q-Bus boards. There is no Unibus version. The
11/84 used an M8190 in a backplane with a Unibus converter (the CPU and
memory were Q-Bus, the rest of the machine was Unibus). The 11/94
worked in a similar way. However, Eric may be right about the 11/84
bus being slightly different from normal Q-Bus, so that the official
11/84 memory may be different.
--
Pete Peter Turnbull
Network Manager
University of York
Received on Sat Dec 13 2003 - 17:50:50 GMT