Siemens SIMATIC S7-200 - Restoring the Program and Memory with a Memory Cartridge; Restoring Memory on Power on (with Memory Cartridge Installed)

CPU Memory: Data Types and Addressing Modes
5-24
S7-200 Programmable Controller System Manual
A5E00066097-02
Restoring the Program and Memory with a Memory Cartridge
To transfer the program from a memory cartridge to the CPU, you must cycle the
power to the CPU with the memory cartridge installed. As shown in Figure 5-21,
the CPU performs the following tasks after a power cycle (when a memory
cartridge is installed):
• The RAM is cleared.
• The contents of the memory cartridge are copied to the RAM.
• The user program, the CPU configuration, and the V memory area are copied
to the permanent EEPROM.
Note
Powering on a CPU with a blank memory cartridge, or a memory cartridge that
was programmed in a different model number CPU may cause an error. Memory
cartridges that were programmed by a lower model number CPU can be read by a
higher model number CPU. However, the opposite is not true. For example,
memory cartridges that were programmed by a CPU 221 or CPU 222 can be read
by a CPU 224, but memory cartridges that were programmed by a CPU 224 will
be rejected by a CPU 221 or CPU 222.
Remove the memory cartridge and power on again. The memory cartridge can
then be inserted and reprogrammed, if desired.
User program
V memory
(permanent area)
CPU configuration
M memory
(permanent area)
RAM EEPROM (Permanent)
User program
V memory
CPU configuration
M memory
Timer and counter
current values
User program
CPU configuration
V memory (permanent area)
User program
CPU configuration
V memory (permanent area)
All other areas of
memory are set to 0.
Memory
Cartridge
Figure 5-21 Restoring Memory on Power On (with Memory Cartridge Installed)