1401 Emulation By IBM

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IBM 360 Mod 30

from Charlie Cleveland Dec 2007
Hi Ed,

WOW !!! I just read your 360/30 page. I am amazed at the memories it conjured.
Gosh, I haven't heard the term ' IPL' in decades.

While going to school to learn programming (1970, they had a 360/30), I was working as an operator at a shop (they had a 360/25) in the Wash DC area. After graduating, I acquired a position as an operator at an insurance company (360/30).

A year and a half later, I finally landed a programming position (COBOL) with a contracting firm (very fortunate for me as this company was started by the people who worked with Grace Hopper, the "Mother of Computers"). During this time, I realized that the 360/30 was by far the most widespread machine in the DC area.

I recall the 1401 emulation both as an operator as well as a contractor.

As an operator, I used the '// FETCH' JCL (I don't recall the parameters) to initiate the 1401 emulation. You also had to turn off the I/O check at the CPU (this was because the 1401 allowed a multi-punch in rows 4 thru 7 whereas the 360 did not).

As a contractor, I had to convert some systems from 1401 to 360. I recall, in the 1401 world, the sign (+, -) was located in the high order byte, wherein the 360 and all subsequent worlds, the sign is located in the low order byte.

I remember the partitioning and spooling. It seems to me, we used two programs in this area, DEBE and DITTO. I believe DEBE was a print spooler and DITTO was a general utility (not sure).

One short story during my time with the insurance company as an operator:

From time to time I had to go into the stock room for printer paper. I noticed there was a small box on the top of one of the shelves. After several month's, I decided to check it out. After blowing off a 1/4" of dust (this box was ancient even in 1971), I realized that I had found an "IBM Port-a-Punch". I asked the DP manager if I could have it and he said OK. Over 36 years later, I still have it here in my office in the original box.
What a wonderful site this is. Thank you so much for the moment of fond memories you have inspired.

au,
Charlie Cleveland


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