12 Jan
2019
12 Jan
'19
10:13 a.m.
On 1/12/19 11:39 AM, Bill Gunshannon via cctalk wrote:
On 1/12/19 12:29 PM, Pete Turnbull via cctalk wrote:
I use this guide in general -
http://web.frainresearch.org:8080/projects/pdp-11/dcj11.php to
understand the key differences in DEC DCJ11 implementations. You can see
how the clock speed, caching and memory type drove differences in
performance and marketing labels.
The 11/83 (M8190-AD or AE) with Non-PMI memory is just a slow 11/83 in
my view. I know RT11 did report it as an 11/73.?? It could be that from
a software perspective, RT11 might not be possible to determine the
actual module in use.
Does the 2MB 11/93 not work with and extra 2Mb of QBUS Non-PMI memory??
I would have thought the upper 2MB would still be addressable, if for
nothing else than for compatibility memory mapped display controllers
and such.
?? Jerry
On 12/01/2019 01:24, Zane Healy via cctalk
wrote:
One confusing part of this. Everything I have read today
seems to say that the only difference between the 11/73
and the 11/83 in a MicroPDP-11 was the memory used.
QBUS = 11/73
PMI = 11/83
I?m pretty sure you could get the /23+, /53, /73,
/83, and /93 in
either a BA23 or a BA123.? I have an actual badged BA23 pedestal for
my /23+.
I'm fairly certain all microPDP-11/23+ systems were only sold in
BA23
boxes, and I think microPDP-11/73 and the later, cheaper, cut-down 11/53
were as well.? But almost all the 11/83 systems I've ever seen were in
BA123 boxes, though they did sell some in BA23 pedestals - I've got one.