Rabbit RabbitCore RCM5400W, Руководство пользователя, Страница: 55 / 120

OEM User’s Manual 49
5.2 Dynamic C Function Calls
5.2.1 Digital I/O
The RCM5400W was designed to interface with other systems, and so there are no drivers
written specifically for the Rabbit 5000 I/O. The general Dynamic C read and write func-
tions allow you to customize the parallel I/O to meet your specific needs. For example, use
WrPortI(PEDDR, &PEDDRShadow, 0x00);
to set all the Port E bits as inputs, or use
WrPortI(PEDDR, &PEDDRShadow, 0xFF);
to set all the Port E bits as outputs.
When using the auxiliary I/O bus on the Rabbit 5000 chip, add the line
#define PORTA_AUX_IO // required to enable auxiliary I/O bus
to the beginning of any programs using the auxiliary I/O bus.
The sample programs in the Dynamic C
SAMPLES/RCM5400W
folder provide further
examples.
5.2.2 Serial Communication Drivers
Library files included with Dynamic C provide a full range of serial communications sup-
port. The
RS232.LIB
library provides a set of circular-buffer-based serial functions. The
PACKET.LIB
library provides packet-based serial functions where packets can be delimited
by the 9th bit, by transmission gaps, or with user-defined special characters. Both libraries
provide blocking functions, which do not return until they are finished transmitting or
receiving, and nonblocking functions, which must be called repeatedly until they are fin-
ished, allowing other functions to be performed between calls. For more information, see
the
Dynamic C Function Reference Manual and Rabbit Semiconductor’s Technical Note
TN213, Rabbit Serial Port Software , both included with the online documentation.
5.2.3 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
USERBLOCK_INFO.C
in
the Dynamic C
SAMPLES\USERBLOCK
folder can be used to determine the version of the
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.