User`s manual

34 RabbitCore RCM2100
4.4 Memory
4.4.1 SRAM
The RCM2100 is designed to accept 32K to 512K of SRAM packaged in an SOIC case.
4.4.2 Flash Memory
The RCM2100 is also designed to accept 128K to 512K of flash memory packaged in a
TSOP case.
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 also discouraged. Instead,
define a “user block” area to store persistent data. The functions writeUserBlock and
readUserBlock are provided for this.
A Flash Memory Bank Select jumper configuration option based on 0 Ω surface-mounted
resistors exists at header JP4. This option, used in conjunction with some configuration
macros, allows Dynamic C to compile two different co-resident programs for the upper
and lower halves of the 512K flash in such a way that both programs start at logical
address 0000. This is useful for applications that require a resident download manager and
a separate downloaded program. See Technical Note 218, Implementing a Serial Download
Manager for a 256K Flash
, for details.
NOTE: Only the Normal Mode (pins 1–2 connected at JP4), which corresponds to using
the full code space, is supported at the present time.
4.4.3 Dynamic C BIOS Source Files
The Dynamic C BIOS source files handle different SRAM and flash EPROM sizes auto-
matically.