I have a couple of AT&T 615MT terminals I'd like to get more information
on. I understand they're capable of running Layers (mouseless) on System
V UNIX, but other than that I have no idea what features they have.
If you have any 615MT documentation, could you please let me know?
All the best,
web at loomcom.com
I was at a small technical conference last weekend (www.devconf.cz) at
the Faculty of Informatics, Brno Masaryk University.
What I didn't know is that it has its own small museum of computing.
I enjoyed it a lot. There's a good range of Sinclair kit and clones,
including various real ZX Spectrum machines (48, Plus, 128 with
vanishingly rare numeric keypad, Plus 2, Plus 2A, Plus 3, Interface 1
and Microdrives, MGT +D, Opus Discovery) and clones including Soviet
(Orel BK-08), Polish (CZ Spectrum 48) and Czechoslovakian (Didaktik
Gama, Kompakt and Kompakt M, with rare built-in 3?" floppy drive) and
a SAM Coup?. There are other Czechoslovak machines, micros and minis
and mainframe parts.
They have an HP 3000, a PDP-11/34 and multiple RL02s, with both VT-120
and VT-220) and a Soviet PDP-11 clone.
Mechanical and early electronic calculators.
And a mediaeval clock!
In the unlikely even folk are passing, it's well worth a visit. I
spent a happy couple of hours in there.
Liam Proven ? Profile: https://about.me/liamproven
Email: lproven at cix.co.uk ? Google Mail/Hangouts/Plus: lproven at gmail.com
Twitter/Facebook/Flickr: lproven ? Skype/LinkedIn: liamproven
UK: +44 7939-087884 ? ?R (+ WhatsApp/Telegram/Signal): +420 702 829 053
Thanks for your feedback. Also, Noel was correct on the typos I made on DD1, DE1, and DF1. I was copying from a scanned .pdf and some strange OCR translation was occurring and I missed correcting those.
Yesterday I stuck the ADV11-A in a MINC-23 with 256 KB memory and verified that it worked. The CSR is different than a MNCAD and the voltage range bits may be different, but when I connected a 40 pin cable and a IDE to screw terminal connector on the I could match up the +4.5 and -4.5 reference voltage signals with the diagram with the screw terminals and then make voltage changes on channel 0 and see the A/D counts change.
Today, I cut the BDAL18 BC1 trace to ground, verified it still worked in the MINC, then moved it to a PDP-11/73 RSX11M+ system I use for hardware testing. The RSX system was not configured for this card and the default 400 vector conflicts (I think) with the bottom of kernel stack so I?ll need to either move the vector switches on the card down or re-sysgen this test RSX system. Thus, the only quick testing I could do is via the CSR.
Also, to make it easy to see values change I used the 2 digit LED display next to the console port to display the least significant bits of the readings. This is a technique I use to debug interrupt routines as you can write a 2 digit octal number with a simple MOV.
I didn?t loop on the status bit because RSX is multiuser/tasking, but just used a 1 second mark time to assure the conversion was done. This would be changed to an interrupt service routine once I fix the vector issue. Using the LED display made the test code very simple:
; TKB commands: IDLE/PR:5/-FP=IDLE
.MCALL EXIT$S MRKT$S WTSE$S
LEDCSR = 177524
ADCSR = 170400
ADBUF = 170402
LEDS: MOV #177777,R0
MOV #100,R1 ; COUNT
10$: MOV R0,@#LEDCSR ; Display inverted contents of R0
CLR @#ADCSR ; Clear A/D status register
INC @#ADCSR ; START A/D
MRKT$S #1,#1,#2 ; Set Mark Time for 1 sec on eflg #1
WTSE$S #1 ; Wait for eflg #1
MOV @#ADBUF,R0 ; Get A/D value
BIS #177700,R0 ; Set all bits high but lower 100
; DEC R0 ; this line counts to 77 octal on display
MOV #177777,@#LEDCSR ; Reset LEDs to .
So Noel and Jerry, you are correct it is that simple. If the A/D was DMA, that would be another situation (like the RX02 controller).
I mentioned this in the thread where I'd asked about basic Microvax II
info, but it may have got lost in traffic...
The machine's H7260 PSU is somewhat unwell - one of the internal +5/12V
supplies appears to be healthy, but the other has outputs which are sitting
at around 2.5V (both on the 5V and 12V rails) under a test load.
1) Are schematics are available online? I couldn't find them (either under
the DEC p/n or the Astec AA13010 one), but perhaps they're buried in
schematics for a specific DEC machine somewhere.
2) Upon initial glance, the 'first' board of the three in the PSU module
appears to be a pair of control relays, bridge rectifiers and capacitors,
supplying +/- DC voltages to the two individual PSU boards. Does anyone
know if I can disconnect these from the PSU boards safely* and measure
their outputs, and if so what voltages I should expect to see? That might
be a good initial test before pointing a finger at the PSU board associated
with the low outputs.
* I mean without component damage - I expect they might be sitting at a
significant DC voltage, so there's an obvious personal safety aspect too ;-)
> From: Mark J. Blair
> I have a single decpack cartridge ... It's marked "decpack 2200 BPI-12"
> and has 12 sector notches in the hub. Does that mean that it was most
> likely used with an RK05 drive in a PDP-11 system?
> I hope that I can procure a matching drive for it one of these days
The come by occasionally on eBait; here's the most recent one (October
They're usually mildly pricy, alas.
> From: Mark Matlock
> Any device which uses backplane pins BC1, BD1, BEl, BF1 or DC1, 001,
> DEl, OF!
Those last are probably typos for "DD1, DE1, DF1".
> Several other pins are also tied to ground on that connector such as
> BC2, BJ1, and BT1.
Yeah, those are all standard Q22 ground pins.
> When I look at the Board connector B pin C side 1 (component side) the BC1
> pin is tied to ground. .. So it looks like if I simply cut the trace
> between the BC1 finger and its connection to ground on the board it
> would become Q22 compatible.
> Is it that simple?
That would be my take on it, yes.
As Jerry Weiss mentions, since it's not a DMA device, once you do that, it
should be Q22-capable; all QBUS devices are supposed (per the QBUS spec) to
use BBS7, along with BDAL0-12, to listen for register accesses, so the fact
that it's not listening to BDAL18-21 should not be an issue.
(Odd factoid: various QBUS CPU's drive various combinations of BDAL13-21
during references to the I/O page; I forget the details off the top of my
head, but Dave Bridgham and I were just looking at that.)
Three ?computing? events are happening:
1) The i-Pad was introduced by S. Jobs 8 yrs. ago and defined a ?new?
computing paradigm for the masses. The reason I mention this event is
because a young friend(20 yrs. old) said ?That?s ancient computing!? What
is one to make of classic-computing then?
2) Bitcoin mining ? The energy usage is extreme because of GPUs. Was
16-bit computer era, employing the 80287, such an energy hog?
3) INTEL doesn?t seem to have been hurt by Meltdown & Specture
financially- speaking. Had excellent earnings and profits for the last
quarter but ?may? change this quarter. However, INTEL marches on going from
4004 to 7980XE. AMD was/in the picture but financially-wise?
Happy computing all!
I?d like to thank whoever it was who added the Abit K8V Pro/Winbond W83627HF with its test results to the TESTFDC page for writing SSSD disks. I?ve been trying to get a similar setup going for a fortnight now and last week found this motherboard on e*ay for Not Many UK Pounds. Coupled with a scrap Athlon64 system from work and a scratched Windows98 CD I eventually got it going earlier and can now read/write single density floppies meaning I can archive the disks I got with my Research Machines 380Z :D
Typical of my luck a contact has also found an Adaptec 1522A that he?ll hopefully send me too, then I?m covered for all eventualities.
Now where did I put that 8? drive...
Binary Dinosaurs - Celebrating Computing History from 1972 onwards
w: binarydinosaurs.co.uk <http://binarydinosaurs.co.uk/> t: @binarydinosaurs