20-101-1138 Rabbit Semiconductor, 20-101-1138 Datasheet - Page 114

• Manufacturer Part Number: 20-101-1138
• Description: RCM4300 RABBITCORE
• Manufacturer: Rabbit Semiconductor

Specifications of 20-101-1138

• 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: 2 MBytes
• 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: RCM4300
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 316-1141

B.4.4.1 RS-232
RS-232 serial communication on header J4 on both Prototyping Boards is supported by an
RS-232 transceiver installed at U3. This transceiver provides the voltage output, slew rate,
and input voltage immunity required to meet the RS-232 serial communication protocol.
Basically, the chip translates the Rabbit 4000’s signals to RS-232 signal levels. Note that
the polarity is reversed in an RS-232 circuit so that a +3.3 V output becomes approxi-
mately -10 V and 0 V is output as +10 V. The RS-232 transceiver also provides the proper
line loading for reliable communication.
RS-232 can be used effectively at the RCM4300 module’s maximum baud rate for distances
of up to 15 m.
RS-232 flow control on an RS-232 port is initiated in software using the
trolOn
of the flow control lines are specified using a set of five macros.
Standard 3-wire RS-232 communication using Serial Ports C and D is illustrated in the
following sample code.
RabbitCore RCM4300 User’s Manual
SERX_RTS_PORT—Data register for the parallel port that the RTS line is on (e.g., PCDR).
SERA_RTS_SHADOW—Shadow register for the RTS line's parallel port (e.g., PCDRShadow).
SERA_RTS_BIT—The bit number for the RTS line.
SERA_CTS_PORT—Data register for the parallel port that the CTS line is on (e.g., PCDRShadow).
SERA_CTS_BIT—The bit number for the CTS line.
#define CINBUFSIZE
#define COUTBUFSIZE 15
#define DINBUFSIZE
#define DOUTBUFSIZE 15
#define MYBAUD 115200
#endif
main(){
}
function call from
serCopen(_MYBAUD);
serDopen(_MYBAUD);
serCwrFlush();
serCrdFlush();
serDwrFlush();
serDrdFlush();
serCclose(_MYBAUD);
serDclose(_MYBAUD);
RS232.LIB
15
15
// set baud rate
// set size of circular buffers in bytes
// open Serial Ports C and D
// flush their input and transmit buffers
// close Serial Ports C and D
, where
X
is the serial port (C or D). The locations
serXflowcon-
114