20-101-1196 Rabbit Semiconductor, 20-101-1196 Datasheet - Page 46

• Manufacturer Part Number: 20-101-1196
• Description: MODULE RABBITCORE RCM3900
• Manufacturer: Rabbit Semiconductor

Specifications of 20-101-1196

• Module/board Type: MPU Core Module
• For Use With/related Products: RCM3900
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 20-101-1196; 316-1155

5.2 Dynamic C Functions
5.2.1 Digital I/O
The RCM3900 was designed to interface with other systems, and so there are no drivers
written specifically for the I/O. The general Dynamic C read and write functions allow
you to customize the parallel I/O to meet your specific needs. For example, use
to set all the Port E bits as inputs, or use
to set all the Port E bits as outputs.
When using the external I/O bus on the Rabbit 3000 chip, add the line
to the beginning of any programs using the auxiliary I/O bus.
The sample programs in the Dynamic C
examples.
5.2.2 SRAM Use
The RCM3900 has a battery-backed data SRAM and a program-execution SRAM.
Dynamic C provides the
into the battery-backed SRAM. The compiler generates code that creates a backup copy of
a protected variable before the variable is modified. If the system resets while the protected
variable is being modified, the variable's value can be restored when the system restarts.
The sample code below shows how a protected variable is defined and how its value can
be restored.
The
backed SRAM without affecting the performance of the application program. Data integ-
rity is not assured when a reset or power failure occurs during the update process.
Additional information on
User’s Manual.
RabbitCore RCM3900 User’s Manual
bbram
WrPortI(PEDDR, &PEDDRShadow, 0x00);
WrPortI(PEDDR, &PEDDRShadow, 0xFF);
#define PORTA_AUX_IO
protected nf_device nandFlash;
int main() {
...
_sysIsSoftReset();
keyword may be used instead if there is a need to store a variable in battery-
protected
bbram
// required to enable auxiliary I/O bus
and
// restore any protected variables
keyword to identify variables that are to be placed
protected
SAMPLES/RCM3900
variables is available in the Dynamic C
folder provide further
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