It is also possible to directly write the parameter values into the corresponding %MWCmd objects and then trigger the execution of the motion command by sending a WRITE_CMD instruction.

The behavior is similar to the one with EFs. However, it is necessary to specify what kind of command is to be executed with the command code byte. If this parameter is not valid, the command will be rejected and the detected error will be reported in the CMD_CODE_INV status object (%MWr.m.c.3.2).

When sending a command through WRITE_CMD, the command object %MWr.m.c.13 is computed internally. Its behavior is exactly the same as the CMD_NB output pin of the EF when the command is sent by EF.

This mechanism can be used to send motion commands from Control Expert Operator Screens, which can’t be done with only EFs.