Want a timout if the DATUM command fails to find the sensor or the Z.

We don't have anything built in to the DATUM command itself. You could make 2 separate DATUM commands, one for the swtich and then one for the Z. Add a timeout to each one.

DATUM(3)

TICKS = 10000 ' 10 seconds

REPEAT

     WA(1)

UNTIL IDLE OR TICKS<0

IF NOT IDLE THEN

     CANCEL

     home_error = 1

ENDIF

WAIT IDLE

IF home_error = 0 THEN

     DATUM(2)

     TICKS = 2000 ' 2 seconds

     REPEAT

          WA(1)

     UNTIL IDLE OR TICKS<0

     IF NOT IDLE THEN

          CANCEL

          home_error = 2

     ENDIF

ENDIF

The second one could be done as a position check, say 1.1 turns of the motor, instead of a timeout. The first datum will set the axis to 0 at the switch, so the MPOS should not go more than one turn before it sees the Z.

Or write your own datum function that includes timeout or position checks.