|.||Kisco Home : An IT Retrospective - 50 Years in the Business||.|
I think my work ethic impressed someone in management because they approached me about taking a Programmer's
Aptitude Test. In those early days of computing, colleges did not offer any curricula for information technology (we just called it Data Processing). Most
employers who were implementing computer systems were looking to their own people to train to do the programming. I took the test and ended up scoring the
highest score the railroad had ever gotten on the test. (Two years later, after I'd been working successfully as a programmer, I took the same test again
at Reader's Digest and failed it miserably . . . so much for the PAT.) The railroad offered me a job as a programmer trainee and I accepted.
Since you could not go to college for programming, the only place to learn was from the computer manufacturer. So, the New York Central sent me off to IBM's programming school in Manhattan, where I started out my programming career by learning "1401 Autocoder." At the end of the class, I started programming on the railroad's IBM 1401 computer system. This first computer was quite different from what we think of today as a computer. It was the size of two desks stacked on top of each other and came from the factory with all of 4 K of memory. On that machine, 4 K of memory meant 4,000 characters of storage, not the 4096 bytes that we think of today. The machine I worked on had a "caboose" on it that included the optional additional 4 K, so we had the huge amount of 8K of memory to work with. That machine also did not have any operating system installed on it (they were another couple of years in the future) nor did it have any disk drives or tape drives. The input unit was a punched card reader where you loaded your programs to run along with your input data. The output units consisted of a line printer and a card punch unit that was integrated with the card reader.
The IBM 1401, first introduced in 1959, and its later cousin the IBM 1410, were variable word length machines. The size of each word, rather than today's standard 4 bytes, was determined by the placement of a wordmark bit. This was a part of the 8-bit character coding known as Binary Coded Decimal (BCD). The character was comprise of 6 bits (4 numeric bits and 2 zone bits) and the other two bits were for the wordmark and parity check. The memory on these systems was actually made up of magnetized "cores" or very small circles that could be charged in one direction or the other (on or off). I even have a small sample of this core memory that I keep clipped to a cork board in my office today as a reminder of where the term "core storage" came from.
After six months or so, I graduated to programming on the "big machine" in the computer room. This was an IBM 7010 (a grown up version of the IBM 1410) which had 100 K of memory, 6 tape drives, a very early disk drive unit and an interactive console which looked an awful lot like an IBM Selectric typewriter. It also had a very early form of an operating system and could actually run two programs at the same time; quite an advanced application for its day. The railroad used this system to keep track of its rolling stock in files on the disk drive. We actually worked on developing the idea of indexed-sequential files on this system and this is one of the applications I worked on.
The disk drive, an IBM 2302, was huge with platters that were about 6 feet across and 8 pneumatic access arms. I remember that if it ever got turned off, like after the blackout, it took at least 30 minutes to warm up and get back up to speed before it could be used. Since there was no operating system to manage the disk contents, we had to keep the disk layout all mapped out so that every area of the disk that was used was pre-assigned a space.
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