Siemens Simatic S7-400 - Manual (Page 467)

CPUs for M7-400
11-39
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
System Cache
For the memory areas of the System ROM, the VIDEO ROM, and the addresses of
BIOS expansions, you can set whether they are copied to the Shadow RAM and
whether the cache should be used.
• System ROM offers you the following possible selections:
By Activating the Option Button... You Determine...
Shadowed that the BIOS address area of 128 Kbytes is
to be copied into the high-speed shadow
RAM. This option cannot be switched off.
Shadowed and Cached that a cache memory is available for this
memory area in addition to shadow RAM.
Note
If you have switched off the cache memory in the “Primary and Secondary Cache”
field, the setting in the “System ROM” field does not change automatically.
• Video ROM offers you the following possible selections:
By Activating the Option Button... You Determine...
Shadowed that the video ROM (32 Kbytes) is copied
into the fast shadow RAM. This accelerates
video output (faster screen buildup).
Shadowed and Cached that a cache memory is available for this
memory area in addition to shadow RAM.
Further accelerates video output.
OK Button
Activating this button returns to the Setup menu. Changes on the setup page are
retained.
CANCEL Button
Activating this button returns to the Setup menu. Deletes all changes you have
made on the setup page.
DEFAULT Button
When this button is activated, the default settings are entered in the setup page
again. The original settings are deleted.