We didn't want to wind up walking around in the rain, so we went to the
Air and Space Museum Annex. It was very cool if you like spending four hours looking at airplanes and such. In the back corner, I was recalled to a time long ago in a lifetime far away when I worked at System Development Corporation operating a Control Data 3800 computer.
The cabinet behind the console is part of the CPU unit. There were more cabinets than that, but some of them housed memory and some housed IO channel interfaces. It was crammed with small circuit cards, each holding a few transistors. The other side was a maze of wires. The cabinet was mostly to contain the air which was cooled and then blown up from under the floor to keep everything cool. All that and it ran at 2MHz and had about the equivalent of a megabyte of memory. It did have hardware for virtual memory, though. The space on the right side of the console was occupied by a selectric typewriter. When it was operating, the lights changed in cool patterns. One of the knobs on the underside of the display to the right of the 3800 logo controlled a speaker which made noises that varied according to the program that was running. After a bit, the operator could recognize patterns as the operating system performed certain functions.
The sign is not the most accurate. It says 48 bits twice and computes the memory size incorrectly. They came with six banks of 32K 48-bit words. That's 192K (8-bit) bytes per bank.
Here I am, standing in memory lane.
The cabinet behind the console is part of the CPU unit. There were more cabinets than that, but some of them housed memory and some housed IO channel interfaces. It was crammed with small circuit cards, each holding a few transistors. The other side was a maze of wires. The cabinet was mostly to contain the air which was cooled and then blown up from under the floor to keep everything cool. All that and it ran at 2MHz and had about the equivalent of a megabyte of memory. It did have hardware for virtual memory, though. The space on the right side of the console was occupied by a selectric typewriter. When it was operating, the lights changed in cool patterns. One of the knobs on the underside of the display to the right of the 3800 logo controlled a speaker which made noises that varied according to the program that was running. After a bit, the operator could recognize patterns as the operating system performed certain functions.
The sign is not the most accurate. It says 48 bits twice and computes the memory size incorrectly. They came with six banks of 32K 48-bit words. That's 192K (8-bit) bytes per bank.
Here I am, standing in memory lane.
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