RS485 – ttyS1, maximum baud rate 115200bps RS232 – ttyS3, maximum baud rate 115200bps Test with the supporting UART script. Max load: 1A. Wire length shall not exceed 1M. GPIO-IN Low level or floating: CPU reads "1". High level (3.3-12V): CPU reads "0". GPIO IN1: echo 338 > /sys/class/gpio/export echo in > /sys/class/gpio/gpio338/direction cat /sys/class/gpio/gpio338/value GPIO IN2: echo 339 > /sys/class/gpio/export echo in > /sys/class/gpio/gpio339/direction cat /sys/class/gpio/gpio339/value GPIO-OUT CPU outputs "1": port outputs 3.3V. CPU outputs "0": port outputs 0V. GPIO output is open-drain with 3.3V@10K pull-up. It can control 5V-12V devices (external pull-up required). GPIO OUT1: echo 335 > /sys/class/gpio/export echo out > /sys/class/gpio/gpio335/direction echo 0 > /sys/class/gpio/gpio335/value echo 1 > /sys/class/gpio/gpio335/value GPIO OUT2 : echo 334 > /sys/class/gpio/export echo out > /sys/class/gpio/gpio334/direction echo 0 > /sys/class/gpio/gpio334/value echo 1 > /sys/class/gpio/gpio334/value |