Not able to send data over UART on nRF52810

RE: Not able to send data over UART on nRF52810

ovrebekk — Tue, 22 Oct 2019 06:48:27 GMT

If your devices are running at different voltages you would need some kind of level shifter on the signals to convert the voltages accordingly.

For one directional signals, such as the reset pin, you can typically get away with a simple transistor circuit, but for bidirectional signals it is a bit more complicated (either a more complex transistor network or a dedicated level shifter chip is needed).

Best regards
Torbjørn

RE: Not able to send data over UART on nRF52810

Sudeep R J — Mon, 21 Oct 2019 08:56:16 GMT

Hi Torbjorn,

I think there is a hardware issue with my board. I was pulling up the DSP reset pin from the BLE and it was not happening as the BLE and DSP work at different voltages. So the voltage given by the BLE is not sufficient for the DSP Reset pin to be pulled high.

I have figured out till this. So a quick rework to my board should work for me I guess.

Thanks for your response.

RE: Not able to send data over UART on nRF52810

ovrebekk — Mon, 21 Oct 2019 08:50:30 GMT

Sorry for the slow response. Hung is currently out of office, and I will help out in the mean time.

Did you have any progress with this?

Do you get any error messages in the code when you try to enable the UART, or write to it?

Have you tried to probe the UART pins with a scope or logic analyzer to see if there is any activity?

Best regards
Torbjørn

RE: Not able to send data over UART on nRF52810

Sudeep R J — Fri, 11 Oct 2019 07:04:44 GMT

Hello Hung Bui,

Yes I did disable the log completely.

I do not want the log messages anyway so i have not enabled the RTT log also. I compared my sdk.config file with that of ble_app_uart but still there is no data that can be seen on the DSP Rx.

Thanks & Regards

Sudeep R J

RE: Not able to send data over UART on nRF52810

Hung Bui — Thu, 10 Oct 2019 12:20:21 GMT

Hi Sudeep,

Have you tried to disable log completely ? (set NRF_LOG_ENABLED = 0)

Or you can set NRF_LOG_ENABLED = 1 but use RTT logging instead of UART.

You can refer to our ble_app_uart example where we use RTT log and UART interface at the same time.