Title: +038=360.000-OU045T_03-PCD2.m4160 PLS SBC - Hardware Manual.pdf
To run an application on the PCD, it is sufficient to load only the user program memory. As this is a RAM, the program and the contents of the texts and DBs (and the other media, registers, flags etc.) may be lost if there is no power and the battery is flat or not connected.Backup memory (Flash)In order to prevent the loss of the program, every PCD CPU has onboard flash memory fitted as standard to back up the user program memory.It is also possible to save DBs on this flash during runtime. This allows key values of registers and flags to be saved to the flash at runtime and reloaded later.Along with the installed onboard flash memory, a flash card can also be used for the user backup program, e.g. PCD7.R500. The use of this card allows the user program and the configuration to be transferred from one controller to another.Even with backup to the flash card, the source files for the project must be retained, as the application is only stored in the PCD as machine code.