Questions tagged [ibm650]
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When did the IBM 650 have a "Table lookup on Equal" instruction?
In 1959, Donald Knuth wrote an assembly program named SuperSoap for the IBM 650. Here is the manual, and here is a listing of the program (in SuperSoap assembly language). Quoting from the abstract:
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Why did the Burroughs 205 not use bi-quinary like the IBM 650?
The IBM 650, one of the first general-purpose digital computers, designed in the early fifties, used decimal digits with bi-quinary representation for reasons discussed here: Why did the IBM 650 use ...
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Why did 1950s-60s computers have such wide words?
Modern general-purpose computers typically have a 64-bit word size, but looking back in time, we see narrower CPUs. In the early 80s, the 68000 dealt with 32-bit addresses but the ALU was only 16 bits ...
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IBM 650 - how many logic gates?
How many logic gates did the IBM 650 have? I'm used to measuring the complexity of a CPU by transistor count, but the 650 was a vacuum tube machine; the number of tubes would also be an interesting ...
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Why did the IBM 650 use bi-quinary?
The IBM 650, announced in 1953, was the world's first mass-produced computer. It represented numbers in decimal, which is understandable, both because it needed to work with exact money amounts, and ...
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Why does an instruction include the address of the next instruction on the IBM 650?
The IBM 650 seems to be a load-store machine. One advantage of a load-store machine is that the instruction can be shorter because there's less pressure to pack more information into it. But the IBM ...
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