Why are the DBs not correctly restored after a "restore program from flash"?

FAQ #101279

 

Problem
On a PCD3.Mxxx0 or PCD2.M5xx0 it is possible to make a user program backup to flash. In case of a program lost, the program is restored. Often it is necessary to restore some values as well. In this case one can copy DBs to the onboard flash using the syswr 3100 (explanation in the manual 26/789). These DBs can be restored as well in case of a program lost. This works well, as long as no additional memory card is in use. As soon as a PCD3/7.R551 or a PCD3.R600/PCD2.R600 is in use, the program backup is stored to the flash card. The DBs on the onboard flash are therefore overwritten during the program restore.

Reason
The reason for this behaviour is, that when executing a program restore, the program is copied from the flashcard to the PCD RAM and to the onboard flash as well. Because of a wrong behaviour of the firmware, the DBs stored on the onboard flash are erased during this procedure.

Solution
The firmware 1.10.51 or higher corrects this problem.