14 Oct
2008
14 Oct
'08
11:14 a.m.
On Tue, Oct 14, 2008 at 12:37 AM, Pete Turnbull
<pete at dunnington.plus.com> wrote:
The exact same board (M8189) is used for two different machines,
PDP-11/23plus and microPDP-11, the difference being the ROMs (and the
chassis) used. It's the ROMs (alone) that that make the difference to the
suffix, and therefore whether the board is designated an 11/23plus CPU or a
microPDP-11/23 CPU.
23-339E2 and 23-340E2 are 2k x 8 and make an PDP-11/23plus (-BA)
23-158E4 and 23-159E4 are 8k x 8 and make a microPDP11/23 (early -BE)
23-238E4 and 23-239E4 are 8k x 8 and make a microPDP11/23 (later -BE)
23-183E4 and 23-184E4 are 8k x 8 and make a microPDP11/23 (-BF)
23-380E4 and 23-381E4 are 8k x 8 and make a microPDP11/23 (-BG)
23-453E4 and 23-454E4 are 8k x 8 and make a microPDP11/23 (-BJ)
Thanks for the details here. I have a pair of 2716's in my M8189 so
that must be the earliest version. I have some MCM68766's I can
program and drop in place and I'll go ahead and do that now that I
know it should work.
You have the 23-380E4 / 23-381E4 images on your site. Do you also
have the 23-453E4 / 23-454E4 images?
-Glen