The optional stop code is represented by which M code?

The optional stop code is represented by M1. In CNC programming, the M codes are used to control various functions of the machine. M1 specifically instructs the machine to stop at that point in the program only if the optional stop function is enabled. This means that if the operator has activated the optional stop feature, the machine will pause at M1, allowing for inspections, tool changes, or other necessary tasks without the program continuing automatically. If the optional stop feature is not activated, the machine will proceed past the M1 command without stopping, thus providing flexibility in the operation of the CNC machine. Understanding the role of M1 in programming is critical for effective machine management during milling operations.