VAR-SOM-AM43 RS485-Port: Difference between revisions
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{{PageHeader|VAR-SOM-AM43 - RS-485 Port}} {{DocImage|category1=VAR-SOM-AM43|category2=Yocto}} __toc__ | |||
Please do the following to enable and test RS-485 port: <br> | Please do the following to enable and test RS-485 port: <br> | ||
1. Perform a loopback at RS-485 port by shorting pins 1 to 3 and 2 to 4 on J11 (on the carrier board). | 1. Perform a loopback at RS-485 port by shorting pins 1 to 3 and 2 to 4 on J11 (on the carrier board). | ||
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# Tx enable: gpio173 | # Tx enable: gpio173 | ||
$ echo 173 > /sys/class/gpio/export | $ echo 173 > /sys/class/gpio/export | ||
$ echo "out" > /sys/class/gpio/gpio173/direction | $ echo "out" > /sys/class/gpio/gpio173/direction | ||
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</pre> | </pre> | ||
3. | 3. Start minicom | ||
<pre> | <pre> | ||
$ minicom -D/dev/ttyO2 -b115200 -8 | $ minicom -D/dev/ttyO2 -b115200 -8 | ||
Latest revision as of 15:30, 24 December 2015
VAR-SOM-AM43 - RS-485 Port
Please do the following to enable and test RS-485 port:
1. Perform a loopback at RS-485 port by shorting pins 1 to 3 and 2 to 4 on J11 (on the carrier board).
2. Type the following commands in the Linux shell to enable:
$ echo 168 > /sys/class/gpio/export $ echo "out" > /sys/class/gpio/gpio168/direction $ echo 0 > /sys/class/gpio/gpio168/value # Tx enable: gpio173 $ echo 173 > /sys/class/gpio/export $ echo "out" > /sys/class/gpio/gpio173/direction $ echo 1 > /sys/class/gpio/gpio173/value
3. Start minicom
$ minicom -D/dev/ttyO2 -b115200 -8
4. Type a few characters at the minicom and see that the loopback is working.