Rabbit RabbitCore RCM3100 User Manual page 21

Distributor of Digi International: Excellent Integrated System Limited
Datasheet of 101-0533 - KIT DEV RABBIT3000/RCM3100
Contact us: sales@integrated-circuit.com Website: www.integrated-circuit.com
—This program demonstrates transmitting and then receiving an
•
SWITCHCHAR.C
ASCII string on Serial Ports B and C. It also displays the serial data received from both
ports in the STDIO window.
To set up the Prototyping Board, you will need to tie TxB and RxC
together on the RS-232 header at J5, and you will also tie RxB and
TxC together using the jumpers supplied in the Development Kit as
shown in the diagram.
Once you have compiled and run this program, press and release S2
and S3 on the Prototyping Board. The data sent between the serial ports will be dis-
played in the STDIO
Two sample programs,
SIMPLE485MASTER.C
, are available to
SIMPLE485SLAVE.C
illustrate RS-485 master/slave com-
munication. To run these sample pro-
grams, you will need a second Rabbit-
based system with RS-485, and you
will also have to add an RS-485 trans-
ceiver such as the SP483E and bias
resistors to the RCM30/31/32XX
Prototyping Board.
The diagram shows the connections. You will have to connect PC0 and PC1 (Serial Port D)
on the RCM30/31/32XX Prototyping Board to the RS-485 transceiver, and you will con-
nect PD4 to the RS-485 transceiver to enable or disable the RS-485 transmitter.
The RS-485 connections between the slave and master devices are as follows.
• RS485+ to RS485+
• RS485– to RS485–
• GND to GND
•
SIMPLE485MASTER.C
lower case letters to a slave RCM3100. The slave will send back converted upper case
letters to the master RCM3100 and display them in the
SIMPLE485SLAVE.C
•
SIMPLE485SLAVE.C
lower case letters to a master RCM3100. The slave will send back converted upper case
letters to the master RCM3100 and display them in the
SIMPLE485MASTER.C
14
window.
and
PC0
PC1
PD4
GND
—This program demonstrates a simple RS-485 transmission of
to program the slave RCM3100.
—This program demonstrates a simple RS-485 transmission of
to program the master RCM3100.
485+
Vcc
bias
DI
A
RO termi-
nation
DE B
/RE
bias
485–
STDIO window. Use
STDIO window. Use
RabbitCore RCM3100
RxC TxC
TxB RxB GND
Vcc
681 W
220 W
681 W