;program to demonstrate how to ADD
;The ADD instruction was not added to the SSEM until August 1948
;until that time, all adding therefore had to be done in software.

01 LDN 28   ;-x to A
02 SUB 29   ;-x - y to A            {=  -(x + y)  }
03 STO 30   ;-(x + y) to Result
04 LDN 30   ;-(-(x + y)) to A       {=  (x + y )  }
05 STO 30   ;x + y to Result
06 STP      ;halt program
28 NUM 5    ;value x to be added
29 NUM 6    ;value y to be added
30 NUM 0    ;location for result x+y