iMX93(9332 soc), pinmux the gpio_io04 & gpio_io05 as LPUART6_TX & LPUART6_RX.
dts:
&lpuart6 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart6>;
status = "okay";
};
pinctrl_uart6: uart6grp {
fsl,pin = <
MX93_PAD_GPIO_IO04__LPUART6_TX 0x31e
MX93_PAD_GPIO_IO05__LPUART6_RX 0x31e
>;
};
when board power on, /dev/ttyLP5 dev created, but when I test the tx & rx pin, no signal received, and TX high, RX low all the time.
Plus, the BT dev connecting the LPUART6_TX & LPUART6_RX, no CTS&RTS pins exists.
#ls -l /dev/ttyLP*
crw------- 1 root tty 242, 0 Sep 10 18:00 /dev/ttyLP0
crw-rw---- 1 root dialout 242, 5 Sep 20 2023 /dev/ttyLP5
I changed the /dev/ttyLP5 group to be tty and I'm sure no gpios occupied by other devs.
Whicherver the termios app(read & write) or stty -F(cat & echo), the /dev/ttyLP5 attr can be saved and succedd to open /dev/ttyLP5, but no signal received by testing the RX&TX pins all the time.
Pls help me out of it or give me some hints or reference doc, Thx
Solved! Go to Solution.
Hello @sibingl
I hope you are doing well.
This behavior is expected, because the driver needs the CTS and RTS "definitions".
You can solve adding the fsl,dte-mode:
&lpuart6 {
compatible = "fsl,imx93-lpuart", "fsl,imx8ulp-lpuart", "fsl,imx7ulp-lpuart", "fsl,dte-mode";
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart6>;
status = "okay";
};
pinctrl_uart6: uart6grp {
fsl,pins = <
MX93_PAD_GPIO_IO04__LPUART6_TX 0x31e
MX93_PAD_GPIO_IO05__LPUART6_RX 0x31e
>;
};
Then, you will be able to get data from the TX signal:
Remember the default speed is 9800 BPS.
Best regards,
Salas.
Hello @sibingl
I hope you are doing well.
This behavior is expected, because the driver needs the CTS and RTS "definitions".
You can solve adding the fsl,dte-mode:
&lpuart6 {
compatible = "fsl,imx93-lpuart", "fsl,imx8ulp-lpuart", "fsl,imx7ulp-lpuart", "fsl,dte-mode";
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart6>;
status = "okay";
};
pinctrl_uart6: uart6grp {
fsl,pins = <
MX93_PAD_GPIO_IO04__LPUART6_TX 0x31e
MX93_PAD_GPIO_IO05__LPUART6_RX 0x31e
>;
};
Then, you will be able to get data from the TX signal:
Remember the default speed is 9800 BPS.
Best regards,
Salas.