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Publication No. SBC329-HRM/1
Functional Description 51
5.3.4
NVRAM
A maximum of 1 MB of FRAM-type memory-mapped non-volatile memory is
provided on the SBC329, and half of this is available to the user for general-purpose
use. The remainder is allocated for system-only use, and is primarily used by BIT to
store test results and sensor data.
Access to the devices is through 64 KB pages mapped into LPC memory space. The
device-selection and addresses of the pages within the devices are set by the
NVRAM page register.
TIP
Only access this device using proprietary driver software.
The NVRAM device has very high read/write endurance (10
14
cycles) and stated data
retention is greater than 10 years.
LINK
For more details on the FRAM, see
Write
Protection
Each area of the NVRAM can be independently write-protected by setting bits in the
EEPROM DIP switch, which can be accessed through the BIOS setup menus.
Write protection for the user device is also set by the backplane NVMRO signal (on
the
–
if either signal is active, the NVRAM is write protected.