CPU 72x
24.05.2019
page 17
1.5.1.3
Memory Map CPU 72x
From the following memory map, it can be seen that two different memory sizes are
distinguished with the CPU 72x:
CPU 725-LT/LTH
CPU 723-T and CPU 727-T/TH
small memory with 256
kB RAM and
512 kB Flash-EPROM
large memory with 1
MB RAM and
1 MB Flash-EPROM
Fig.15: Memory map CPU 72x
Legend:
Boot SW
Boot software
MOS
MAS operating system
Backup
User program and data in flash EPROM
User Program
User program
VAR_RETAIN
Warm start variables
Parameter
Domain in flash EPROM for user parameters
IMPORTANT
With the small memory CPUs, when the 'Backup/Restore' function is executed
in the CAP1131 programming tool, the whole RAM content is copied into the
flash EPROM, i.e. the user program and the data. When the CPU is started up
in operation mode RUNB, all variables (including warm start variables) are
overwritten with the content of the variables in the flash EPROM!
Flash
RAM
User Program
MOS
Backup
Boot SW
MOS
MOS
MOS
Flash
RAM
Backup
Boot SW
MOS
MOS
MOS
User Program
MOS
User Program
Backup
Parameter
User Program
User Program
Backup
Backup
Reserve
VAR_RETAIN
VAR_RETAIN