> Date: Sun, 19 Apr 2020 15:29:44 -0400
> From: Chris Zach <cz at alembic.crystel.com>
> To: CCTalk mailing list <cctalk at classiccmp.org>
> Subject: pdp11/84 PMI memory: What is the problem with Q bus?
> Message-ID: <3efa4105-3d3d-bb98-0358-8c46fca0fdcf at alembic.crystel.com>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
> So I picked up an 11/84 CPU, 3mb of memory, and a 11/84 Unibus card on
> Ebay. Goal is to speed up my fastest 11 here
>
> For boot time, the diagnostics run in 13 seconds (from when it starts to
> prompt) on the 11/73 board I have and 13 seconds on the 11/84 board.
> This is with a camintonn 2mb half height memory board.
>
> Put in the first PMI module above the 11/84 CPU and tried it out. This
> is a CA rev board which apparently only works in a Unibus pdp11 and not
> a Q-bus one. Apparently it does work.
>
> So what exactly was the bug with the older PMI memory? Block mode DMA,
> I'm using an MTI ESDI controller which can do 16 word block DMA on Q
> Bus. Something else?
Chris,
Congrats on the PDP-11/84! I also have a PDP-11/84 that uses one of Joerg?s Hoppe?s
UniBone devices to simultaneously emulate MSCP disks, RL02 disks (including the
RL02 Load/Ready/WriteProtect/ and fault lights) and a DL11.
I have a question about something you said above, that you are using a MTI
ESDI disk controller and then you mention Qbus block mode DMA. Are you able to use a
Qbus MTI controller in the 11/84?s Qbus section of the backplane? This is something
I?ve often wondered about but never tried.
Also, you mention putting the PMI memory above the 11/84 CPU. In the 11/83
Qbus backplane this is of course determines whether the M8637 memory is accessed via
Q22 or PMI. In the 11/84 System Maintenance Guide Figure 2-8 shows the
CPU card above the memory which if you were to do this in the 11/83 would mean
that the memory will be accessed via Q22 and essentially become an 11/73.
In my 11/83 I have run both configurations to understand and measure the benefit of PMI.
As has been mentioned the 11/84 can use any of the M8637 memory boards but the
11/83 can only use the M8637-D or -E versions. For anyone who is curious about what
Happens when a M8637-C version board is used as PMI memory in an 11/83 I can speak
>From experience. This was running RSX11M+ and it boots fine but after a few minutes if
The system is active, the console starts to report that various installed tasks are corrupted
And the system will XDT a bit later. After this the disk is corrupted and you will need to restore
the system disk from backups after you get the correct PMI memory boards.
I?m not completely sure how the write DMA operations put bad data through the disk controller
(I was using an Emulex UC07 with a SCSI2SD) into the disks but that is what happens.
Mark Matlock
Old IBM magnetic media
I am hoping someone can help me with a project. I?m volunteer at our local
music museum (National Music Centre/Studio Bell.) They are restoring a
vintage Synclavier, an early digital audio workstation, which happens to
have an embedded DEC PDP 11/23. Part of the museums purpose is to restore,
maintain and make available these instruments for musicians to use in
addition to static displays.
The Synclavier should have a matching VT100, but that is the only component
the museum does not currently have for this functioning device. Yes, the
VT100 can be easily emulated, but as a museum, historical accuracy is also
vital.
I was wondering if anybody had any leads on a VT100 that might be donated?
Thanks for any help!
Anyone seen Rik Bos around? I sent him some 12920/21 mux boards to repair, and he got to keep some but haven?t heard anything in a long time?. I may start playing with the HP2000 again soon ?
Old IBM magnetic media
Yes, two cartridges have a total capacity of 100mb, the same as the staging
disks, IBM 3330-1.
However, the entire cartridge contents are not staged, only the cylinders
that have the requested data.
Not sure why your cartridges were empty.
Here?s a link to my ?working ? 3850 mass storage robotic arm for your
viewing pleasure!
*https://www.youtube.com/watch?v=V8ifNxDgxuY&pbjreload=10*
<https://www.youtube.com/watch?v=V8ifNxDgxuY&pbjreload=10>
?\_(?)_/?
So I picked up an 11/84 CPU, 3mb of memory, and a 11/84 Unibus card on
Ebay. Goal is to speed up my fastest 11 here
For boot time, the diagnostics run in 13 seconds (from when it starts to
prompt) on the 11/73 board I have and 13 seconds on the 11/84 board.
This is with a camintonn 2mb half height memory board.
Put in the first PMI module above the 11/84 CPU and tried it out. This
is a CA rev board which apparently only works in a Unibus pdp11 and not
a Q-bus one. Apparently it does work.
So what exactly was the bug with the older PMI memory? Block mode DMA,
I'm using an MTI ESDI controller which can do 16 word block DMA on Q
Bus. Something else?
Here's the output from RT11.
.show all
RT-11FB (S) V05.05
Booted from DU6:RT11FB
USR is set SWAP
EXIT is set SWAP
KMON is set NOIND
TT is set NOQUIET
ERROR is set ERROR
SL is set OFF
EDIT is set KED
FORTRAN is set FORTRA
KMON nesting depth is 3
Global .SCCA flag is disabled
PDP 11/83 Processor
2048KB of memory
Floating Point Accelerator Unit
Extended Instruction Set (EIS)
Memory Management Unit
ECC Memory
Cache Memory
PMI Memory
60 Cycle System Clock
Device I/O time-out support
Error logging support
Memory parity support
System job support
Global .SCCA support
FPU support
Extended unit support
Device Status CSR Vector(s)
------ ------ --- ---------
EL Not installed 000000 000
LD Installed 000000 000
BA Installed 000000 000
DY Not installed 177170 264
VM Installed 177572 250
SP Installed 000000 110
XL Not installed 176500 300 304
DL Installed 174400 160
MS Not installed 172522 224
DU Resident 172150 154
LS Not installed 176510 310 314
NL Installed 000000 000
TT (Resident)
DU (Resident)
DU6 = DK , SY
MQ (Resident)
LD
DL
VM
SP
BA
NL
9 free slots
Job Name Console Level State Low High Impure
--- ---- ------- ----- ----- --- ---- ------
0 RESORC 0 0 Run 000000 103232 105046
No multi-terminal support
Address Module Words
------- ------ -----
160000 IOPAGE 4096.
132174 DU 5570.
103274 RMON 5856.
001000 ..BG.. 16990.
LD0 is DU6:RTTST.DSK[6000.]
OK Looking to purchase "Sensicall" and the ATT Code-Com" bell system attachment that woukd allow deaf to tap morse over phone lines? thanks? Ed? at? SMECC
Looking to purchase CODE A PHONE? bell system attachment that woukd allow,deaf to send morse code through bell system phone.? Respond off list...... they would tap on litte finger pad . this,was,an attachment to a regular phone,set made in later 60s or 70s. Person on other end would see light flash I guess... drop us a line off list.
>
> Guys,
>
> I have been collecting all types of computer punched cards for a few years
> now. In the distant past I actually used them!
>
> I am desperately looking for two types I do not have been able to find a
> sample of:
> * Jacquard fabric/carpet loom cards. OK, not computer but the
> ancestor, for completeness of the history. There may be several formats of
> these.
>
>
Something like this?
http://www.ricomputermuseum.org/Home/interesting_computer_items/jacquard-lo…
--
Michael Thompson
Guys,
I have been collecting all types of computer punched cards for a few years
now. In the distant past I actually used them!
I am desperately looking for two types I do not have been able to find a
sample of:
* Jacquard fabric/carpet loom cards. OK, not computer but the
ancestor, for completeness of the history. There may be several formats of
these.
* Original Hollerith card, 12 rows by 24 columns. Once again, this is
a long shot.
Well if you don't ask, you never get! Thank you for your interest. Peter
