Two UART's pin configuration in nRF52833 QFN40

[Sai Mukesh]

Hi,

     I want to develop a device using nRF52833. I am using QFN40, so can I use two UART connections. If yes, then what are the Tx, Rx pins for both the UART's

[Jørgen Holmefjord]

Hi,

Yes, nRF52833 supports two UARTE instances (UARTE0 and UARTE1), as you can see in Registers. All nRF52 series chips has a pin crossbar feature, allowing any GPIO to be assigned to any serial peripheral like UART, SPI, TWI, etc. You should however avoid using pins marked as "Standard drive, low frequency I/O only" in Pin assignments for high frequency peripherals. The pins are controlled in FW, and both UARTE instances needs to be configured and initialized before use.

Best regards,
Jørgen

[Sai Mukesh]

Hi,

Thanks for the reply.

But I want exact pin numbers which I can use as UART

[Jørgen Holmefjord]

Hi,

Like I said in my previous reply, ALL GPIOs can be assigned to the UARTs, but not all are recommended. Here is a table of available GPIOs on nRF52833 QFN40 package and their recommended usage:

Green shows GPIOs with no restriction. Red shows pins with frequency/drive restrictions, which should be avoided. I have also marked some pins in yellow. The yellow pins are shared with other functionality (32.768 kHz crystal pins and pin reset), so you might also want to avoid these pins if these functionalities are used in your product

Best regards,
Jørgen

[Sai Mukesh]

Hi,

Thanks for the reply.

How to flash the program in nRF52833 QDAA QFN40. What are the pins I should use for programming.

[Jørgen Holmefjord]

See my answer in this ticket. The programming procedure are the same for all nRF52 series chips.