How many serial communication(RX/TX) channels does Boron have?

Currently, I use Boron RX/TX pins to communicate with some other board, but now I want to it to communicate with another additional board through another RX/TX channel. I know Electron has at least two if not three serial communication channels, how many does Boron have?

Sadly the Xenon board has 2 sets of Rx/Tx pins but the Boron has only 1 set (the processor itself has 3 sets). It was a choice of what processor pins to bring out given the size constraints of the board.

A pity as I have a similar need - I use one to communicate with a 4DSystems display and would like second to link to a Xenon on the same board.

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While you already got your answer, here would be the place for own investigations :wink:

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The nRF52840 only has two hardware UARTs, not three. And there is only one exposed to the user on the Argon and Boron because the nRF52 connects to the network coprocessor (ESP32 on the Argon and u-blox modem on the Boron) by serial, leaving only one port on RX/TX.

It is possible to add UARTs by I2C or SPI; I recommend the SC16IS7xx series as they are known to work.


Thank you so much guys.

Hey @rickkas7, is there more info on the data rate for this UART interface? How does that relate to the WiFI data transfer rate?
I see in the Argon datasheet that the BLE/NFC radio has a 2Mbps max rate. I am thinking BLE is always going to be faster than the WiFi connection… unless we can execute code within the ESP32?

@Pescatore, the nRF5284 datasheet is a bit hard to read (it’s very complex and verbose) but here’s an excerpt for the UARTE interface:

6.34 UARTE — Universal asynchronous receiver/transmitter with EasyDMA The Universal asynchronous receiver/transmitter with EasyDMA (UARTE) offers fast, full-duplex, asynchronous serial communication with built-in flow control (CTS, RTS) support in hardware at a rate up to 1 Mbps, and EasyDMA data transfer from/to RAM. __

Looks like 1MBit/sec

Is that also the speed at which it operates with the ESP32 for WiFi communication?

Thanks - I will follow up on this device as one possible solution to my needs

This is my library for the SC16IS740/50/60 (single port) chip:

I built a board with the dual port SC16IS752 in the Adafruit FeatherWing form-factor but I haven’t made the software driver modification for it. It should be pretty simple; the chips are nearly identical beyond the port selection.

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