17 Jan
2012
17 Jan
'12
1:06 a.m.
Glen Slick wrote:
On Jan 16, 2012 10:28 AM, "Shoppa, Tim"
<tshoppa at wmata.com> wrote:
Can you describe the fine details which make the QED993 different
Most of the 3rd party boards (including much of
the Mentec stuff) are
"just J11's" maybe sped up/speed selected.
Tim.
I wish the QED993 was just a fast J11. It's a Xilinx FPGA implementation
which has some compatibility issues.
from the J11 chip? For example, the early PDP-11
hardware did
not support the MFPT instruction. The PDP-11/73, PDP-11/83 and
PDP-11/84 which supported PMI memory could be tested for. The
Maintenance Register at 177750 had difference values for systems
which included the J11 chip.
Any specific differences for the QED993? Also, what is the official
spelling of QED993? If it is going to be noted, it is best to use the
official spelling used by QED.
I'd have to look at its configuration options. It
might be possible to
alter the return values of the CPU type registers.
That would not be needed if the compatibilities between the QED993
and the J11 from DEC can be tested for.
Jerome Fine