Serial2 on Boron Needed: Availability and Instructions

I need to use the Serial2 hardware UART on the Boron. The documentation explicitly references the existence of hardware Serial2 and even includes the otherwise extraneous detail that the input buffer therefor is 128 bytes and immutable.

Because of the above, Serial2 must exist and be somehow accessible, or else this specific information would not be in Particle Boron documentation.

But I have found zero results in this forum nor on Google how to use it, that is, to which pins Serial2 RX/TX are mapped, and if any other special considerations are necessary.

If this is attributable to my ignorance or flawed information-finding skills, then I apologize. But it is very useful to have multiple Serial ports and frankly I am surprised that I seem to be the first to ask the question. It would impose undue development strain on my system if an unavailable Serial2 on Boron required me to use SPI or I2C instead. These are just 4 different 32-byte packets streamed every 0.5 seconds to my Boron which I’d like to have remotely streamed over MQTT when remotely enabled for such streaming, and ignored at all other times.

Serial1 input is already occupied by my core-competency one-minutely 132-byte-packets which I upload. I am using the Boron solely as an LTE internet gateway. I have a separate MCU actually collecting sensor data and streaming to Boron over Serial. Trust me that in my particular case/application, there are good reasons for this separation and not attempting to have the Boron continuously poll sensors.

  1. Is Serial2 accessible on the Boron?
  2. If so, what pins are RX/TX?
  3. If so, are there any special considerations beyond simply creating a UART object as with Serial1?

Thank you in advance.

The datasheet here and here states only 1 UART - where is the reference to a second Part ?

I’m pretty sure that’s an oversight on the docs side (tag @rickkas7)

However, I’d value this explicit statement higher

than this “explicit” inline side note

Especially when looking at the datasheet
https://docs.particle.io/datasheets/cellular/b-series-datasheet/#peripherals-and-gpio

There is a second UART on the nRF52840 but that is occupied with communication with the cellular module.

ScruffR is correct. The second serial port on the nRF52840 is connected to the cellular modem on the Boron and ESP32 on the Argon.

There are only two serial ports available on the Xenon, which has no network coprocessor.

One option is to add a SC16IS740, connected by I2C or SPI.

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