101-1226 Rabbit Semiconductor, 101-1226 Datasheet - Page 97

• Manufacturer Part Number: 101-1226
• Description: RCM3900 DEV KIT UNIVERSAL
• Manufacturer: Rabbit Semiconductor
• Series: RabbitCore 3900r
• Type: MPU Moduler

Specifications of 101-1226

• Contents: RabbitCore Module, Dev. Board, AC Adapter, Cable and Dynamic C® CD-Rom
• For Use With/related Products: RCM3900
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 316-1137

B.4.6.1 RS-232
RS-232 serial communication on the Prototyping Board is supported by an RS-232 trans-
ceiver installed at U9. 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 3000’s signals to RS-232 signal levels. Note that the polarity
is reversed in an RS-232 circuit so that a +5 V output becomes approximately -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 RCM3900 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
serXflowcontrolOn()
port (E or F). The locations of the flow control lines are specified using a set of five macros.
Standard 3-wire RS-232 communication using Serial Ports E and F is illustrated in the fol-
lowing sample code.
RabbitCore RCM3900 User’s Manual
SERX_RTS_PORT—Data register for the parallel port that the RTS line is on (e.g., PGDR).
SERX_RTS_SHADOW—Shadow register for the RTS line's parallel port (e.g., PGDRShadow).
SERX_RTS_BIT—The bit number for the RTS line.
SERX_CTS_PORT—Data register for the parallel port that the CTS line is on (e.g., PCDRShadow).
SERX_CTS_BIT—The bit number for the CTS line.
#define EINBUFSIZE
#define EOUTBUFSIZE 15
#define FINBUFSIZE
#define FOUTBUFSIZE 15
#define MYBAUD 115200
#endif
main(){
}
serEopen(_MYBAUD);
serFopen(_MYBAUD);
serEwrFlush();
serErdFlush();
serFwrFlush();
serFrdFlush();
serEclose(_MYBAUD);
serFclose(_MYBAUD);
function call from the
15
15
// set baud rate
// set size of circular buffers in bytes
// open Serial Ports E and F
// flush their input and transmit buffers
// close Serial Ports C and D
LIB\RS232.LIB
, where
X
is the serial
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