18 Jun
2021
18 Jun
'21
11:17 p.m.
Tom said
On 6/17/21 6:57 AM, Steve Malikoff via cctalk wrote:
Yes my M7261 board drawing appears to be the earlier one, similar to the GT40 drawing but
is
revision N instead of M. (I myself have an early 11/05 s/n 151 but it has a later M7261 in
it.)
Tom said
If you look at the board layout for the M7261, the E rev board has a large open
area, devoid of ICs,
whereas
the non-E rev board has a uniform distribution of ICs across the surface.
--tom
I have a couple different drawing sets for the
11/05 and while some have the matching M7260
schematic, only the GT40 drawings (I found on bitsavers) has the M7261E schematic:
http://www.bitsavers.org/pdf/dec/graphics/VT11/GT40_Graphic_Terminal_Engine…
The GT40 drawings has the PROM listings and related, so I am hoping that they match what
is in the
two boards.
My original PDP-11/05 print set that came from the BHP steelworks is
titled just 'PDP-11/05 Engineering
Drawings' and the drawings are for machine revision 1105-0. It covers the early 11/05
with the cast metal
grille with no slots (as seen in the 11/05 handbook) rather than the later 11/05 with the
plastic slotted
grille.
The dates on the drawings are 1972 and some of the microcode listing dates are different
to the 'PDP-11/05-S,
11/10-S systems engineering drawings' bitsavers scan and the GT-40 scan, and some of
them are the same.
I'm not sure where I look to see what revision of the M7261 it shows, as the Rev box
in the bottom right
seems to jump around, eg. Rev N, Rev K, Rev H or is that just the minor drawing revision
for that page?
Steve
From the ex-BHP print set the microcode listing details
and Page Revision Control Sheet latests are
----
K-MP-KD11-B-1 MICROPROGRAM FLOW Rev B
(PRCS: Rev. B [BAAAAABAAAAAAAAAAAAAAA]) (Listing: K-MP-KD-11B-1 Rev. A 27-JUL-72)
----
K-MP-KD11-B-2 MICROPROGRAM SYMBOLIC LISTING Rev D
(PRCS: Rev. D [DABCBA]) (Listing: K-MP-KD-11B-2 Rev. A 27-JUL-72)
----
K-MP-KD11-B-3 MICROPROGRAM BINARY LISTING Rev D
(PRCS: Rev. D [DABBBBA]) (Listing: K-MP-KD-11B-3 Rev. A 27-JUL-72)
----
K-MP-KD11-B-4 MICROPROGRAM CROSS REF LISTING Rev D
(PRCS: Rev. -) (Listing: K-MP-KD-11B-4 Rev. * 2-MAY-72)
----------------------------
M7620-0-1 DATA PATHS Rev. N
(PRCS: Rev. N [NNNNMMMNMMMM])
M7260-0-8 DATA PATH ROM PATTERNS Rev. ? (same as GT40)
----------------------------
M7261-0-1 CONTROL LOGIC AND MICROPROGRAM Rev. P
(PRCS: Rev. P [PNHHJKJHJMKKKH])
M7261-0-1 CONTROL LOGIC ROM PATTERNS Rev. A (same as GT40)
(PRCS: Rev. A [AAAAAAAAAAAAAAAAA])
Steve.