Difference between revisions of "EDSAC"

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(add order code table)
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| H n      || Copy the number in storagae location n into the multiplier register
 
| H n      || Copy the number in storagae location n into the multiplier register
 
|-
 
|-
| V n      || Multiply the number  
+
| V n      || Multiply the number in storage location n by the number in the multiplier
 +
|          || register and add the product into the accumulator
 
|-
 
|-
| *Z      || Multiply the number
+
| N n      || Multiply the number in storage location n by the number in the multiplier
 +
|          || register and subtract the product into the accumulator
 +
|-
 +
| T        || Transfer the contents of the accumulator to storage location n and clear the accumulator
 +
|-
 +
| *Z      || Stop the machine 
 
|-
 
|-
 
|}
 
|}

Revision as of 21:28, 18 May 2007

Conceived in 1946 and the machine did its first calculation in the summer of 1949

Order Codes

Order Description
A n Add the number in storage location n into the accumulator
S n Subtract the number in storage location n from the accumulator
H n Copy the number in storagae location n into the multiplier register
V n Multiply the number in storage location n by the number in the multiplier register and add the product into the accumulator
N n Multiply the number in storage location n by the number in the multiplier register and subtract the product into the accumulator
T Transfer the contents of the accumulator to storage location n and clear the accumulator
*Z Stop the machine
*The addresses in these order codes need not be zero.
** The addresses in these orders may be k.p-2 where k is odd, provided that the addresses do not exceed 2047.