I am trying to receive a string on UART 2 of CL-SOM-iMX6, in the serial boot-up logs i am able to see that ttymxc1/ttymxc2/ttymxc3/ttymxc4 enabled but i am not able to read any incoming data .
in the .dtsi file i am setting the status = "okay" for UART2/UART3/UART4/UART5
serial console -
imx6q-pinctrl 20e0000.iomuxc: pin MX6Q_PAD_EIM_D27 already requested by 20e0000.iomuxc; cannot claim for 21e8000.serial
imx6q-pinctrl 20e0000.iomuxc: pin-48 (21e8000.serial) status -22
imx6q-pinctrl 20e0000.iomuxc: could not request pin 48 (MX6Q_PAD_EIM_D27) from group uar2grp on device 20e0000.iomuxc
imx-uart 21e8000.serial: Error applying setting, reverse things back
21e8000.serial: ttymxc1 at MMIO 0x21e8000 (irq = 291, base_baud = 5000000) is a IMX
21ec000.serial: ttymxc2 at MMIO 0x21ec000 (irq = 292, base_baud = 5000000) is a IMX
21f0000.serial: ttymxc3 at MMIO 0x21f0000 (irq = 293, base_baud = 5000000) is a IMX
console [ttymxc3] enabled
21f4000.serial: ttymxc4 at MMIO 0x21f4000 (irq = 294, base_baud = 5000000) is a IMX
pin configurations in .dtsi -
/* pins for ttymxc1 */
pinctrl_uart2: uar2grp {
fsl,pins = <
MX6QDL_PAD_EIM_D27__UART2_TX_DATA 0x1b0b1
MX6QDL_PAD_EIM_D27__UART2_RX_DATA 0x1b0b1
>;
};
/* pins for ttymxc2 */
pinctrl_uart3: uar3grp {
fsl,pins = <
MX6QDL_PAD_EIM_D24__UART3_TX_DATA 0x1b0b1
MX6QDL_PAD_EIM_D25__UART3_RX_DATA 0x1b0b1
>;
};
/* pins for ttymxc3 console */
pinctrl_uart4: uart4grp {
fsl,pins = <
MX6QDL_PAD_KEY_COL0__UART4_TX_DATA 0x1b0b1
MX6QDL_PAD_KEY_ROW0__UART4_RX_DATA 0x1b0b1
>;
};
I am able to see the square wave on oscilloscope when I transmit the string by placing probes on the hardware lines, i want to view the same character on the serial console , I am not able to see the characters that are received .
Can anyone please tell me what all changes I have to do or the steps to follow to achieve it ?
Hi Igor,
I have tried using "cat" to read from ttymxc1, it's sort of in a hang state , in the sense nothing is read from ttymxc1.
Is there any other UART configuration changes that have to be done?
Hi Ajay3
this board was developed and supported by compulab, suggest to post issue
on its support portal:
https://mediawiki.compulab.com/w/index.php?title=Support
Best regards
igor
Hi Ajay3
example of reading from serial console can be found on
https://www.technexion.com/support/knowledgebase/using-a-serial-port-from-a-linux-shell/
https://unix.stackexchange.com/questions/42376/reading-from-serial-from-linux-command-line
Best regards
igor