101-1218 Rabbit Semiconductor, 101-1218 Datasheet - Page 50

• Manufacturer Part Number: 101-1218
• Description: KIT APPLCTN RABBITCORE RCM4010
• Manufacturer: Rabbit Semiconductor
• Series: RabbitCore®r

Specifications of 101-1218

• Main Purpose: *
• Embedded: *
• Utilized Ic / Part: RCM4010
• Primary Attributes: *
• Secondary Attributes: *
• Processor To Be Evaluated: Rabbit 4000
• Interface Type: Ethernet
• Operating Supply Voltage: 12 V
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• Other names: 316-1156

4.6 Memory
4.6.1 SRAM
RCM4000 modules have 512K of data SRAM installed at U16.
4.6.2 Flash EPROM
All RCM4000 modules also have 512K of flash EPROM installed at U3.
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
Designer’s Handbook
4.6.3 NAND Flash
The RCM4000 model has a NAND flash to store data and Web pages. The NAND flash is
particularly suitable for mass-storage applications, but is generally unsuitable for direct
program execution. The NAND flash differs from parallel NOR flash (the type of flash
memory used to store program code on Rabbit-based boards and RabbitCore modules
currently in production) in two respects. First, the NAND flash requires error-correcting
code (ECC) for reliability. Although NAND flash manufacturers do guarantee that block 0
will be error-free, most manufacturers guarantee that a new NAND flash chip will be
shipped with a relatively small percentage of errors, and will not develop more than some
maximum number or percentage of errors over its rated lifetime of up to 100,000 writes.
Second, the standard NAND flash addressing method multiplexes commands, data, and
addresses on the same I/O pins, while requiring that certain control lines must be held sta-
ble for the duration of the NAND flash access. The software function calls provided by
Rabbit for the NAND flash take care of the data-integrity and reliability attributes.
Sample programs in the SAMPLES\RCM4000\NANDFlash folder illustrate the use of
the NAND flash. These sample programs are described in Section 3.2.1, “Use of NAND
Flash (RCM4000 only).”
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NOTE: Rabbit 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.
for additional information.
Rabbit 4000 Microprocessor
RabbitCore RCM4000