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Tricks for Demos

Collected by Ed Thelen


No adding devices to 1401 - Dag, 11/12/04
I am *not* in favor of adding such devices to the 1401.

The system is what it is and will be displayed in that fashion.


-----Original Message-----
From: Van Snyder []
Sent: Friday, November 12,

"Ronald Mak" wrote:

> Question #2: How hard would it be to hook up a laptop to the 1401 to
> act as a card reader? This would save us the effort to punch cards.

Consider also hooking up SCSI devices. I have two ExaByte 8200's, an
8505, and an 8900. You can't see the tape spinning, so it's not as
impressive as a "real" tape drive. Other SCSI tape drives would work
with the same interface. Once you get SCSI interfaces to the TAU (or
indeed the card reader, disk interface, ...) you could hook a PC to

... be on lookout for [demo programs] - Van Snyder 11/12/04
-----Original Message-----
From: Van Snyder []
Sent: Friday, November 12,
"Ronald Mak" wrote:
> Task #2: All of us should be on the lookout for any 1401 programs and
> utilities, especially ones that we can use as demos. In particular, we
> need Autocoder or SPS assemblers that run on the 1401 if we want to
> write our own demos or conduct programming classes.

I have a few. I have the Autocoder that Dick Weaver sent me and two core- dump routines. I've disassembled both of them. I have a listing for a core-to-punch routine, but I haven't transcribed it or disassembled it.

I have two-tape autocoder but never got it to work. I suspect the "deck" is an install deck, and that one needs to remove the bootstrap loader cards from between the phases, but I haven't had time to fool with it.

I have SPS that I've never done anything with. IIRC, I got two-tape Autocoder and SPS from Paul Pierce.

I have the source code for Autocoder, which I keyed in from the CE manual and assembled with my Autocoder. Except for slightly different strategies to assign set-word-mark instructions arising from DA's to individual load cards, the deck I produced is the same as the one I got from Dick, so I think the source is OK.

> Task #3: Evaluate 1401 simulators and emulators. Dan McInnis has
> already started with one. Each evaluator should e-mail a short summary
> of what was good or bad. This will be useful information to give out to
> students of our classes.

I've used simh_v3.2 for several things, but Autocoder doesn't work in it. I suspect there's something wrong with load-mode tape input, but I haven't been able to repair it. It has facilities for breakpoints and dumping, and to configure the simulator for many different machine configurations. I just added a trace, and Bob Supnik just added a history buffer. It doesn't do column binary read or punch, or move-and-binary-[de]code. (Does the CHM machine have column binary?) Other than not running Autocoder, it appears to be accurate.

I have the simulator that Newcomer and Jaeger wrote, but it's for Windoze, which I don't have, so I never compiled it or ran it.

I wrote an Autocoder that doesn't do macros (other than CHAIN) or IOCS. It's all in Fortran 90. I don't have a Windoze Fortran compiler, but I'm confident it's portable. Does anybody want the source, or a Linux executable to play with?

HYPE about 1403 chain breaking - LeRoy Kaump via Bob B. 11/12/04
Hi Bob... Yea, I've seen some concern in the forum!

The pattern that put's a load on the chain is 1 2 3 3 4 5 5 6 7 7 8 9 Etc.... This causes ALL the hammers to fire in 1 printscan instead of the normal 48 (1/3 on each 3 subscans)

I have never heard of any damage, BUT it normally will give a SYNC CHECK due to the sudden load on the drive motor! The chain is pretty robusk & all the mis-information about it breaking and going thru a cover is HYPE!

I've seen broken chains but they just get loose in the cartridge & maybe a end sticks out... I guess if the chain was almost ready to break.. this pattern might do it!