I have a question about UART.

[starlight]

Hello.

I have implemented a simple source code to transmit UART data to a PC using the nRF52840-DK board.

I transmitted 0x31, 0x32, 0x33, and I have confirmed that this data is received correctly on the PC.

After confirmation, I have built the project to fit the custom development board with nRF52833 connected, and downloaded the corresponding source code onto it.

ex)

1. Create a new application -> create blank app 

2. new project -> copy source

3. bulid (nRF52833 DK. set TX - 0.15, RX - 0.17)
4. download

 

The desired results are not being received as opposed to the previous outcome.

I've checked the TX, RX pin configurations as well as the baud rate, stop bit, data bit, parity, and flow control values, but it seems like the issue lies elsewhere.

Since the received values are consistently the same, it appears that the issue is not related to the baud rate.

Could you give me advice that might help me guess the cause?

plz...

[nordicator_prim3]

You said you were using a custom nrf52833 dk, do you mean you are using this board?

If you are using that one, then P0.15 is connected to LED3 which might be messing up your signal. If you wanted to use P0.15 as a normal pin on that DK you would have to cut the trace at SB7, but I would recommend just picking any other unused pins.

You can see which pins the DK is using for special functionality (buttons, LEDs, etc.) by looking at the bottom of the DK.

I wouldn't think that the LEDs would disrupt the data like that but figured I would take a guess. If you source code is all the same, it made me suspect something hardware related as it should not be an issue.

[starlight]

No, it's a board developed separately based on nRF52833.

Nothing is connected to the pins.

So, I was wondering if there are any specific settings to configure or anything else to check.

The image below captures a part of the circuit.

Below is the project file attach. Do you think there might be an issue with the source code?

project file : 8255.uart_test.zip

Thank you.