Receive external data through UART on Thingy:91

[T1mS_]

Hi,

For my project I need to receive 9 bytes of data from our main board. This data gets send using UART. 

By looking at the pin diagram I could not find specific pins on the Thingy:91 to use as UART RX and TX.

So my question, are there any GPIO pins capable of handling an UART connection?

And if yes, which are they and last but not least how the code would look like.

Thanks,

Tim

[MJD093]

Hi,

Any P0.## pin can be used as UART pins. You just need to set them up in the device's tree structure. The Perpiheral for UART# is given the P0.## pins that you set up in the .dts files and will configure them for you according to the configuration.

See https://github.com/NordicPlayground/fw-nrfconnect-zephyr/blob/a2c36f15843f9e11bd997cf5e72b0b4d69a552f7/boards/arm/nrf9160_pca10090/nrf9160_pca10090_common.dts#L83

The above link shows how this is done for the nRF9160 PCA10090 Development Kit.

In the device files for the PCA20035 (the Thingy:91) you just need to set up your desired pins for RX and TX like the above.

The default UART Pins on the Thingy91 are currently set as https://github.com/NordicPlayground/fw-nrfconnect-nrf/blob/b456fb40c4912e3d435b9ee029d8ef24b113f7d0/boards/arm/nrf9160_pca20035/nrf9160_pca20035_common.dts#L165

[T1mS_]

Hi MJD093 ,

Thanks for the answer. So the Pins are set to 18 and 19:

Are these meant by this?

(https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.sdk5.v15.3.0%2Fble_sdk_app_cts_c.html&cp=5_0_4_2_2_7)

Thanks,

Tim

[MJD093]

Hi Tim,

No, those are test pads. The test pads 18 and 19 are connected to the Power Management IC (see Thingy:91 hardware files, PCA20035_Schematic_And_PCB pdf, page 5).

[T1mS_]

Ok, I understand the TP stands for the test pads.

But I still can't figure it out which of the GPIO pins I can access. There are some free holes to solder pins on but they are not named:

[MJD093]

The headers you have marked there are headers P6 and P7. They can be found on page 6 of the hardware pdf.

As for how to integrate with the Thingy:91, I will leave that question for Nordic as I don't honestly know how you would interface with it. I don't see any points for that.

I was just answering your original question you had on UART Pins and the code for enabling them