[nSLUG] Cleaning out my desk...

Robin Murray subscriptions at robinandmariette.com
Mon Nov 12 22:46:53 AST 2007


Ha ha! That's a crude way to run a program. Not boring at all, very 
interesting...

Jack Warkentin wrote:
> Well, you shouldn't be feeling old. The first program I wrote, using 
> punched cards, of course, was in either January or February 1959 for an 
> IBM 650 computer. This machine had a rotating magnetic drum memory. 
> Every instruction had two addresses, the second of which was a "jump" 
> address - instead of having an Instruction Counter, the address of the 
> next instruction to be executed was this "jump" address. There was an 
> Assembler program whose major job was to calculate the jump addresses 
> based on the opcode of the instruction - depending on the opcode, its 
> execution time could vary. The idea was to make sure that the drum 
> memory had rotated just enough so that the next instruction to be 
> executed was just under the drum's read/write head when it was needed.
>
> I could go on of course but won't bore you any more.
>   




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