You're doing everything right, except for one small detail which is not mentioned in the IOmappings doc. I guess we should probably add it!
you need to enable level translation. In practice, this means setting another GPIO (linux gpio4) high.
echo 4 > /sys/class/gpio/export
echo out > /sys/class/gpio/gpio4/direction
echo 1 > /sys/class/gpio/gpio4/value
Thanks for your solution.
I also found the method to control TX/RX pins on Linux from:
But I still cannot receive anything when I used: cat /dev/ttyS0
I already tested the TX/RX by using the Arduino IDE.
I used another Arduino board to test it.
Galileo was connected to the Arduino board through TX/RX, and it's worked.
The PS -A after entering GPIO setting command
ttyS0 00:00:01 login
I figured out that the TX/RX and ttyS0 are worked.
If we want to get output by cat /dev/ttyS0, we need to login as a terminal console first.
I used an Arduino to enter the username and password, and it's worked.
It's pretty inconvenient... so that maybe we need to disable the ttyS0 console before building kernel?
I'm sorry. Are you saying there is a getty session spawning on ttyS0? (i.e. arduino pins 0 and 1, rx & tx)
There shouldn't be. Otherwise it wouldn't work in the IDE either.
Which serial port are you trying to connect to (audio jack or arduino pins)?