I need to configure UART2 to send/receive data.
I can send the from i.MX, but can not receive.
I took a look at 44 pin with oscilloscope and I see that it's strongly pulled high whenever there's no strong pullups at scheme. To be sure that it's not a hardware issue, I've turned off the uart2 and configured i.MX uart2 rx pin as an output gpio. Having this, I was able to drive it high and low.
I used the following connection scheme when tested the communication.
PC | CC6UL
tx - 44 rx
rx - 43 tx
On both sides I've used minicom as a serial console.
In my build I've used ccimx6ulstarter as a reference because my schematics is almost the same.
My device tree parts looks the following way:
imx6ul-ccimx6ulstarter.dts:
&uart2 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart2>;
status = "okay";
};
&iomuxc {
pinctrl-0 = <&pinctrl_hog>;
imx6ul-ccimx6ul {
pinctrl_uart2: uart2grp {
fsl,pins = <
MX6UL_PAD_UART2_TX_DATA__UART2_DTE_RX 0x1b0b1
MX6UL_PAD_UART2_RX_DATA__UART2_DTE_TX 0x1b0b1
>;
};
};
pinctrl_hog: hoggrp {
fsl,pins = <>;
};
};
Got tried a different pullups, but the result is the same.
Any clues where to look at ?