Siemens Simatic S7-200 System Manual page 142

CPU Memory: Data Types and Addressing Modes
User Program
CPU configuration
V memory
M memory
Timer and Counter
current values
Figure 7-12
When you upload a program from the CPU, as shown in Figure 7-13, the user program and
the CPU configuration are uploaded from the RAM to your computer. When you upload the
data block, the permanent area of the data block (stored in the EEPROM) is merged with the
remainder of the data block (if any) that is stored in RAM. The complete data block is then
transferred to your computer. The size of the permanent V memory area depends on your
CPU. See Section 10.1.
User program
CPU configuration
V memory
M memory
Timer and Counter
current values
Figure 7-13
7-12
User program
CPU configuration
Data block (DB1): up to the
maximum V memory range
S7-200 CPU
User program
CPU configuration
DB1 (up to the maximum size of the
permanent V memory area)
RAM
Downloading the Elements of the Program
User program
CPU configuration
Remaining parts
of DB1
RAM
Uploading the Elements of the Program
User Program
CPU configuration
V memory
(permanent area)
M memory
(permanent area)
EEPROM
S7-200 CPU
User program
CPU configuration
Permanently stored
V memory
part of DB1
(permanent area)
M memory
(permanent area)
EEPROM
S7-200 Programmable Controller System Manual
C79000-G7076-C230-02