Instruction type ANA R in 8085 Microprocessor

In 8085 Instruction set, ANA is a mnemonic, which stands for “ANd Accumulator” and “R” stands for any one of the following registers, or memory location M pointed by HL pair.

R = A, B, C, D, E, H, L, or M

This instruction is used to AND contents of R with Accumulator’s content. The result thus produced for this AND operation will be stored back in to the Accumulator over writing its previous content. As R can have any of the eight values, there are eight opcodes for this type of instruction. It occupies only 1-Byte in memory.

Let us consider ANA E is an example instruction of this type. As it is a 1-Byte instruction so in memory only a single Byte will get allocated for it during execution. Let us consider the initial content of Accumulator is ABH and register E is CDH. So after The result of execution of this instruction has been depicted in the following tracing table −

The internal calculation will be done as shown below −

(A) ABH ---> 1010 1011
(d8) CDH ---> 1100 1101
              ---------
      ANA E ---> 1000 1001 (89H)

The timing diagram against this instruction ANA E execution is as follows −

Summary − So this instruction ANA E requires 1-Byte, 1-Machine Cycle (Opcode Fetch) and 4 T-States for execution as shown in the timing diagram.