Barcode PLCENGCHANGE
From PlcWiki
How does it work:
A barcode with the following content is loaded on the client:
PLCENGCHANGE; old_part; new_part
Subsequently, the operator is prompted to scan the car number from which the change will take effect. After it is scanned, a prepareEngineeringChange request is sent to the kernel with the specified data, and the kernel is created in the / usr / local / plc / var / engchanges / prepared directory (may not exist in advance), a subdirectory named the same as the car from which the change is to take effect. A file under the name of the old part will be created in this subdirectory and its contents will be the new part. Then the operation data script PREPARE_ENGCHANGE is called, which should create a feedback message for JIS. The implementation of this script is very similar to the standard script printing script. Once the car in question passes END_OF_ASSEMBLY, the file from the / usr / local / plc / var / engchanges / prepared / <ProductID> / directory should be moved to the / usr / local / plc / var / engchanges / active / directory (this should be should create if it does not exist) and so ship_message should be able to easily recognize that the part is to be replaced (and by what - see the contents of the file) by a simple test for the existence of the file.
An example of all of the above is on the plcclvkrnl kernel, including the new kernel version and the PREPARE_ENGCHANGE script.