20-101-1139 Rabbit Semiconductor, 20-101-1139 Datasheet - Page 52

• Manufacturer Part Number: 20-101-1139
• Description: RCM4310 RABBITCORE
• Manufacturer: Rabbit Semiconductor

Specifications of 20-101-1139

• Module/board Type: MPU Core Module
• Product: Microcontroller Modules
• Data Bus Width: 8 bit
• Core Processor: Rabbit 4000
• Clock Speed: 58.98 MHz
• Interface Type: Ethernet
• Flash: 1 MByte
• Timers: 10 x 8 bit
• Operating Supply Voltage: 3.3 V
• Board Size: 72 mm x 47 mm x 21 mm
• For Use With/related Products: RCM4310
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 316-1142

5.2.4 User Block
Certain function calls involve reading and storing calibration constants from/to the simulated
EEPROM in flash memory located at the top 2K of the reserved user block memory area
(3800–39FF). This leaves the address range 0–37FF in the user block available for your
application.
These address ranges may change in the future in response to the volatility in the flash
memory market, in particular sector size. The sample program
the Dynamic C
ID block, the size of the ID and user blocks, whether or not the ID/user blocks are mir-
rored, the total amount of flash memory used by the ID and user blocks, and the area of the
user block available for your application.
The
tents of the user block that you are using in your application (the calibration constants in
the reserved area and the ID block are protected).
5.2.5 SRAM Use
The RCM4300 module has a battery-backed data SRAM and a program-execution
SRAM. Dynamic C provides the
placed into the battery-backed SRAM. The compiler generates code that maintains two
copies of each protected variable in the battery-backed SRAM. The compiler also generates
a flag to indicate which copy of the protected variable is valid at the current time. This flag
is also stored in the battery-backed SRAM. When a protected variable is updated, the
“inactive” copy is modified, and is made “active” only when the update is 100% complete.
This assures the integrity of the data in case a reset or a power failure occurs during the
update process. At power-on the application program uses the active copy of the variable
pointed to by its associated flag.
The sample code below shows how a protected variable is defined and how its value can
be restored.
The
battery-backed SRAM without affecting the performance of the application program. Data
integrity is not assured when a reset or power failure occurs during the update process.
Additional information on
User’s Manual.
RabbitCore RCM4300 User’s Manual
USERBLOCK_CLEAR.C
bbram
main() {
NOTE: Since RCM4300 RabbitCore modules have a serial boot flash that shares the
protected int state1, state2, state3;
...
_sysIsSoftReset();
serial flash SPI lines with other devices, exercise care when accessing the user block.
Pay attention to the instructions associated with the user block function calls in the
Dynamic C LIB\Rabbit4000\BIOSLIB\IDBLOCK.LIB library.
keyword may also be used instead if there is a need to store a variable in
SAMPLES\USERBLOCK
bbram
sample program shows you how to clear and write the con-
protected
and
// restore any protected variables
protected
folder can be used to determine the version of the
keyword to identify variables that are to be
variables is available in the Dynamic C
USERBLOCK_INFO.C
in
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