There have been a few versions of the utility imd2raw.c floating around
that will take Dave Dunfield's ImageDisk-created images (i.e. an .IMD file)
and make a linear binary image devoid of any metadata. This is similar to
the function of Dave's IMDU.COM program's /b switch.
I've corrected a problem with the assumption that all imd2raw.c descendants
to date have made: sectors that have a skew (i.e. not 1-1 interleaved)
weren't linearized correctly. The skewed sectors need to be written out in
"sorted" order, which is not necessarily captured/physical order. This is
easily verified by comparing output from "IMDU /b" to earlier imd2raw
outputs on any .IMD that has a sector skew that isn't 1, 2, 3 [...].
It's up on github here:
https://github.com/RetroFloppy/imd2raw
Hello,
I'm an employee with the National radio astronomy observatory here in Socorro New Mexico.
As part of our NGVLA upgrades, we are seeking to get rid of old data tapes from the tape reel days of Computing. These contain things such as the boot loaders, OS, specific collection programs and antenna movement programs.
I personally would hate to see these just wind up in the literal dumpster and would like to see them sent out to a museum or an archiving body that can preserve them and keep them safe as a dynamic part of history.
If anyone is interested or knows someone who would be interested in the VLAs data tape library please let me know.
V/R
Danielle Werts
Front end engineer
VLA Socorro New Mexico
I am Michael St. Clair, Chuck's nephew by marriage. I'm writing from his
account to establish bona fides; apologies for any surprise it might cause.
You appear to be the people he considered his professional peers, so I'm
reaching out to you for some help. Chuck had little warning before he
passed. He left his equipment and development environments in working
order, but without a legacy plan. I'm a software engineer and data
archivist, and my aunt has asked me to find good homes for his equipment
and IP. I'm going to organize and open-source the software and other IP
that he hadn't already released. However, I don't know how to safely
use, maintain, or even store his physical gear.
I'm only in Eugene for a couple more days on this particular trip. is
there any specific physical information (that doesn't require
disassembly) that might be useful to potential adopters? I don't have
time to make a complete inventory, but here's a list of highlights and a
Drive folder containing some photographs. This is not (yet) a formal
"come and get it" offer, but it's likely a prelude to one (excluding
business documents and computers).
Highlights:
- Multiple 8-inch floppy drives in built-like-a-truck housings
- Dozens of assorted 80s and 90s-era I/O devices -- ZIP drives, 5 1/4"
readers, etc.
- rack-mounted HP 7970B tape drive
- another full-height rack-mounted 9-track tape drive with external
control panel; no manufacturer or model number on anything I can get to
- custom-built 'tape dehydrator'
- around a thousand pieces of assorted removable media, primarily 3.5",
5 1/4", 8", CD, DVD, and a variety of late-90s and 00s digital tape
formats. Per labels and spot-checks, their contents range from
widely-distributed commercial software to Sydex master floppies to lost
BASIC dialects to industrial control software in CP/M formats. Basically
25 years of Chuck's professional life and the industry around it.
- full electronics workbench with partially-finished projects, including
something involving Pertec controllers
- a variety of functioning vintage keyboards, from IBM Model Ms to
something apparently taken from an industrial control station.
Drive folder:
https://drive.google.com/drive/u/1/folders/1KUs-x6t4OtzS_b7lxYMM7i-GxNi-QRv3
I'd very much appreciate any input.
-- Michael St. Clair
Peter,
I also had the same problem when using RSX11M instead of M+.
Below is a quick Macro-11 program that sends two VT100 escape sequences.
The first clears the screen and the second sends the cursor home.
It can be easily modified for other terminal types if needed.
For command line editing that works with RSX11M, take a look at the MCE command line editor.
It is a great DECUS program found on RSX SIG Tape Spring 1989 in [265,1]
Best,
Mark
>TYP CLR.MAC
.TITLE Reset VT Terminal
.MCALL QIOW$S,EXIT$S
.EVEN
MSG:
.ASCII <33>/[2J/<33>/[H/
LEN = . - MSG
.EVEN
START: QIOW$S #IO.WVB,#5,#1,,,,<#MSG,#LEN,>
EXIT$S
.END START
>MAC CLR=CLR
>TKB
TKB>CLR=CLR
TKB>/
TKB>TASK=…CLR
TKB>//
>PIP LB:[1,54]/NV/CO=CLR.TSK
>INS $CLR
The russians build PDP11's and VAXes. They made chips similar to the
special DEC chips. For example there is an K559IP2 which is an DS8640,
and there is an K559IP1 and they list an DS3881 as equivalent, 4 NAND
gates "standard DEC" Bus driver ..hmm.
1,2-3, 4,5-6 10,11-9 and 13,14-12. ..input,input-output. 16 VCC, 8 GND,
7,15 free. It is an 16 pin 300mil DIP.
Now I have problems to find a Datasheet for an DS3881 which is NOT an
CCFL Inverter from Maxim/Dallas/Analog but I' pretty shure I've seen such
beasts already in the past.
An DEC8881 is sitting next to an DS8640 on a DLV11 I have in my hands..but
this is an DIP14 Chip (similar to an 7401 or an 7439).
What the heck could a DS3881 be?
(DEC Bus drivers are getting rare those days, that's the cause that I've
bought those russian chips in the past for cheap..
Regards,
Holm
--
Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe,
Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583
info(a)tsht.de Tel +49 37292 709778 Mobil: 0172 8790 741
Recently I got a nice and complete PDP-8/s from the US. The power supply
uses a ferroresonant transformer which in addition to the standard primary
and secondary windings has a separate 2.3H winding connected in series to a
2uF 660VAC capacitor forming a resonant "tank" circuit. The transformer's
secondary side and the resonant circuit are operated in saturation. There
is a magnetic shunt to prevent the primary side going into saturation as
well. It accepts a wide input voltage range, but is very sensitive to the
input frequency of 60Hz. This is quite a nice if not elegant design for the
period in question, but maybe not the most efficient.
As I live in Australia I get 240VAC and 50Hz as opposed to the US 115VAC
and 60Hz.
I can easily convert our 240VAC to 115VAC with a step-down transformer, but
cannot easily supply 115VAC at 60Hz. So I was considering using a step-down
transformer to get the 115VAC, but modify the resonant "tank circuit" for
50Hz.
Unfortunately there is some magic I don't understand. The resonant
frequency of a LC circuit with L=2.3H and C=2uF is about 75Hz not the
expected 60Hz.
Otherwise I could just solve the standard LC resonant circuit formula for C
and plug in 50Hz and 2.3H to get the required C.
Obviously ferroresonant transformers are more complex than this former
software engineer can grasp. Could any experienced EE with relevant
transformer knowledge please chime in and help me understand how to
redimension the tank circuit to use 50Hz instead of the original 60Hz input.
Obviously I could replace the entire power supply with two modern switch
mode supplies to create the two rails, but it would be really nice to keep
the original supply and just reversibly adapt it for 50Hz.
Thanks and best regards
Tom
So, I may just be spoiled from using RSX11M-PLUS and now expect too much
from the RSX11M OS. But it seems to me the CLS command would be a
nice-to-have, but I am not able to find anything about it. So did that not
exist for RSX11M? How does one clear the screen in that environment?
-Peter
https://www.raspberrypi.com/products/rp2350/
From postings, I know that folks use the RP2350 for interfacing; the trade press has been shipping news of RP's rev A4 datasheet in volume.
The datasheet should tell all. However, the 5V tollerance of the "IO" pins is significant for its simplification of TTL interfacing; the maximum supply and output voltage remains 3v3. See section 14.8.2 (p 1335) et seq - NB the FT indication.
Martin
I tried to contact rsts.org using their web site form, but it threw a
server error when I tried.
I have two pieces of info for them, if they hang out here:
1) The files at
http://www.rsts.org/autoindex.php?dir=distros/RSTS_tapes/V_10.0/ and
http://www.rsts.org/autoindex.php?dir=distros/RSTS_tapes/V_10.1/
cannot be downloaded: access Forbidden error.
2) I have a product code for the RSTS 10.0 distribution tape (they say
"Unknown DEC Product Code" on the index page.)
The code on the actual tape is BB-P016P-BC RSTS/E V10.0 INSTALL 16MT9
(Unfortunately, my tape has not yet responded to my attempts to read it
- I think the signal that ought to tell the drive it is 1600 BPI PE
isn't being recognized by my HP SCSI tape drive - it thinks the tape is
800BPI, but it works OK with other 1600BPI tapes.)
JRJ
