FAQ: It seems that sometimes not all variables are correctly written to the PLC by the RGM module, although the system driver variable states that the recipe was written successfully and the option "write synchronously" is active. How can this be?

FAQ: It seems that sometimes not all variables are correctly written to the PLC by the RGM module, although the system driver variable states that the recipe was written successfully and the option "write synchronously" is active. How can this be?

When reading a RGM recipe immediately after writing a RGM recipe, with a driver that has the option "keep update list in memory" active, and recipe variables that have been read previously, it can happen that a read cycle is currently in progress, and the recipe read recipe action uses partly new values and partly old values from the PLC (the driver read cycle is asynchronous to the RGM read action). 

This way under fast timing conditions it can seem that the recipe was not properly written, although in fact the driver did not yet update all variables in the read cycle, and the recipe was written properly. 

One option can be to disable the option "keep update list in memory" in the driver configuration and not use the recipe variables in other modules. In this case, reading the recipe will request all variable values from the PLC and there are no existing values in the Service Engine that can be used.