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RSB-4220 User Manual
32
2.5.11.3
UART1 RS485 test
Switching SW8 to set UART1 working at RS485, connect 2x20Pin’s Pin27 and Pin 29
to RS485 port of ADAM, then connect UART4 port to RS232 port of ADAM, run pro-
gram to transmit data between UART1 and UART4.
RSB-4220 RS485 can not support auto flow control, it need be controlled by cus-
tomer APP.
root@am335x
‐
adv:/unit_tests#
./AutoRun_uart485
‐
p
/dev/ttyO1
/dev/
ttyO4
‐
t
6
Open uart /dev/ttyO1 OK ....
Open uart /dev/ttyO4 OK ....
Writing : helloworld!
Reading : helloworld!
->TX/RX Signal pass
+-----------------------------------+
| UART RS485 Testing PASS |
+-----------------------------------+
Close uart /dev/ttyO1 OK ....
Close uart /dev/ttyO4 OK ....