The 3540 was the reader/punch that was to replace the card reader/punch
system. Which it did at both my college (while I was there) and at my
first job (where it replaced the 96 column card system) just before I
got there.
The 3740 and 3742 were the replacement for the card punch machine. They
were highly programmable. You could set up programs where some
characters "punched" as packed decimal and other characters were punched
as display characters. It would also sum-check fields in a single record
and automatically punch final "sums records".
The 3540 had a AWSOMA: Optical Media AttachTOC that contained a VOL1
record and multiple HDR1 records which supported multiple files. It had
tracks and records. I am fuzzy, but I think it supported different
record lengths (set in the HDR1 for each file). I know you could punch
both 80 and 96 (in separate files).
The VTOC design was also used in the Optical Media Attach Feature, which
was actually 'emulated' on the P360/P390 in the AWSOMA dirver.
(All "facts" subject to dropped memory bits due to old age.)
Tony Thigpen
R.S. wrote on 5/13/20 6:59 PM:
I just checked bitsavers and found some information about 3540
1. Capacity - it depends. There were several types and subtypes, and
sub-subtypes of diskettes. Approximately 256kB to 1,2 MB, however 3540
used only those low capacity. (details available on request)
2. Feeding media - automatically, not manually.
3. There were two types of 3540, single and double drive.
4. The purpose was to deliver data from keypunch (wrong!) data entry
stations. At the times before CRT screens became popular.
However still I have no idea about system support. How to write data on
diskette, how to read from diskette, how to recognize volume ID, etc.
No, I'm not going to use it, but I'm just curious.
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