AND to AC
This is an instruction that performs the AND logic operation on pairs of bits in AC and the memory word specified by the effective address. The result of the operation is transferred to AC. The rnicrooperations that execute this instruction are:
D0T4: DR <-M[AR]
D0T5: AC <- AC /\ DR, SC <--- 0
The control function for this instruction uses the operation decoder D0 since this output of the decoder is active when the instruction has an AND operation whose binary code value is 000. Two timing signals are needed to execute the instruction. The clock transition associated with timing signal T4 transfers the operand from memory into DR. The clock transition associated with the next timing signal T5 transfers to AC the result of the AND logic operation between the contents of DR and AC. The same clock transition clears SC to 0, transferring control to timing signal T0 to start a new instruction cycle.