One Address Instructions

One Address instruction

It used an implied accumulator (AC) register for all data manipulation. For multiplication/division, there is a need for a second register.

LOAD  A      AC ® M [A]
ADD  B     AC ® AC + M [B]
STORE T     M [T] ® AC   X = (A +B) × (C + A)

All operations are done between the AC register and a memory operand. It’s the address of a temporary memory location required for storing the intermediate result.

LOAD C    AC ® M (C)
ADD D    AC ® AC + M (D)
ML T    AC ® AC + M (T)
STORE X    M [×]® AC