Serial Communication - RabbitCore RCM4500W User Manual

the RCM4510W's header J4 cannot be used with the Prototyping Board without modifying the Prototyp-
ing Board.
B.4.4 Serial Communication
The Prototyping Board allows you to access the serial ports from the RCM4510W module.
Table B-3 summarizes the configuration options.
Table B-3. Prototyping Board Serial Port Configurations
Serial Port
A
B
C
D
E
F
Serial Ports E and F may be used as serial ports, or the corresponding pins at header location J2
may be used as parallel ports.
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 approximately -10 V and 0 V is
output as +10 V. The RS-232 transceiver also provides the proper line loading for reliable com-
munication.
RS-232 can be used effectively at the RCM4510W module's maximum baud rate for distances of
up to 15 m.
User's Manual
Header Default Use
J2 Programming Port
J2 XBee RF Module
J2, J4
J2, J4
J2
J2
Alternate Use
RS-232
RS-232
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RS-232
RS-232
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