FRDM-RW612 UART0/1 suddently stopped outputting

[james_zhu]

Hi，

I am using  wireless uart demo(sdk 25.09.00); At the beginning, the uart1(Flexcom1 GPIO8/9) works normally. While, I just reconnected the wires Connected to USB adapter, the uart1(Flexcom1 GPIO8/9) is not print.  I change UART  to FLexcom3， all print is ok.  I change to Flexcom0(GPIO2/3) also not work.  And I reset and reboot many times, It also not work. I think Flexcom0/1  is may be physical damage due some reason, such as ESD.  

I using below ways to change print from flexcom3 to flexcom1 or flexcom0：

1. frdmrw612_wireless_uart\source\pin_mux.c  -- line 65 IO_MUX_SetPinMux(IO_MUX_FC3_USART_DATA);  to  IO_MUX_SetPinMux(IO_MUX_FC1_USART_DATA)

2.frdmrw612_wireless_uart\board\board.h  --line 30 #define DEBUG_CONSOLE_UART_INDEX 3 to #define DEBUG_CONSOLE_UART_INDEX 1

Could help me check the modification? and How to confirm whether the serial port function of flexcom0/1 is physically damaged？Has anyone encountered a similar problem？

I sincerely hope you can reply soon.

[james_zhu · Accepted solution]

Hi Ricardo,

Your reply remind me.  I found the reason. The hardware is not damaged. There are two sets of GPIO8/9 on the board, but the UART function or SPI function is selected through SJ13 and SJ16. Initially, I connected to pins 2 and 4 of J1, which correspond to the UART function pin and are the default hardware connection. Later, after unplugging and reinserting, I mistakenly thought that GPIO/8/9 on J2 on the PCB was also GPIO8/9 of RW612. Moreover, My modification of the program from UART3 to UART0/1 was correct. After connecting to the correct TXD and RXD, UART0/1 can now output correctly.

Thanks,

james

[Ricardo_Zamora]

Hello,

Hope you are doing well. Could you please clarify what do you mean with " While, I just reconnected the wires Connected to USB adapter, the uart1(Flexcom1 GPIO8/9) is not print"?

Can you share a photo of the connections?

Best Regards,

Ricardo

[james_zhu]

Hi Ricardo,

my mean is " I just do a general action,  changed the wires (GPIO8/9 and GND) connected the serial screen to the USB adapter(uart to PC, in the photo).

Here is the photo, thanks.

[Ricardo_Zamora]

Hello,

Could you please clarify the physical connections you are using on the FRDM? Header and pin.

Did you make any HW change?

Best Regards,

Ricardo

[james_zhu]

Hi Ricardo，

   I used the pin. No HW change.    Could you help me confirm whether my software code modifications are correct for Flexcom1(GPIO8/9) as the UART?

James,

Thanks

[Ricardo_Zamora]

Hello,

Could you please provide the requested information?

On the FRDM, what are the Header and Pin you are using for GPIO 8 and GPIO 9?

As you might know, GPIO_50_ARD_D8 is connected to CC Logic for USB Type-C Applications | NXP Semiconductors.

And GPIO_52_ARD_D9 should work correctly, as it does not need any HW change on the FRDM.

Best Regards,

Ricardo