In 8085 Instruction set, CMC stands for “CoMplement the Carry flag”. It performs complement operation on the cy flag, and the result is stored back in the cy flag.
|Mnemonics, Operand||Opcode(in HEX)||Bytes|
The result of execution of this instruction has been depicted in the following tracing table −
|2001||3F||CMC||Complement of Cy when Cy=1|
The timing diagram against this instruction CMC execution is as follows −
Summary − So this instruction CMC requires 1-Byte, 1-Machine Cycle (Opcode Fetch) and 4 T-States for execution as shown in the timing diagram.