Hi,
I am using Nanopi Neo board and I need RS485 driver to control DE pin automatically.
I have prepared DTS Overlay file:
/dts-v1/;
/plugin/;
/ {
compatible = "allwinner,sun8i-h3";
fragment@0 {
target = <&uart1>;
__overlay__ {
status = "okay";
pinctrl-names = "default";
pinctrl-0 = <&uart1_pins &uart1_de_pin>;
rs485-rts-gpios = <&gpio6 8 0>; /* PG8 active-low */
linux,rs485-enabled-at-boot-time;
rs485-rts-delay = <0 300>;
};
};
fragment@1 {
target = <&uart2>;
__overlay__ {
status = "okay";
pinctrl-names = "default";
pinctrl-0 = <&uart2_pins &uart2_de_pin>;
rs485-rts-gpios = <&gpio0 2 0>; /* PA2 active-low */
linux,rs485-enabled-at-boot-time;
rs485-rts-delay = <0 300>;
};
};
};
I produced dtbo file from dts one with the command: dtc -@ -I dts -O dtb -o rs485.dtbo rs485.dts
I copied this rs485.dtbo file to /boot/dtb/overlay. Also I added rs485 string to ArmbianEnv.txt and rebooted.
But only TX works, RX doesn't.
What should I do else to make it work?