Rabbit RabbitCore RCM4400W Product Manual - page 50
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RabbitCore RCM4400W
4.5 Memory
4.5.1 SRAM
All RCM4400W modules have 512K of battery-backed data SRAM installed at U6, and
512K of fast SRAM are installed at U7.
4.5.2 Flash EPROM
All RCM4400W modules also have 512K of flash EPROM installed at U5.
NOTE: Rabbit Semiconductor recommends that any customer applications should not be
constrained by the sector size of the flash EPROM since it may be necessary to change
the sector size in the future.
Writing to arbitrary flash memory addresses at run time is discouraged. Instead, define a
“user block” area to store persistent data. The functions writeUserBlock and
readUserBlock
are provided for this. Refer to the
Rabbit 4000 Microprocessor
Designer’s Handbook
for additional information.
4.5.3 Serial Flash
The 1 MByte serial flash memory on the RCM4400w is used to support the FPGA for the
Wi-Fi circuits, and is not available for customer use.