I have a Boron 2G/3G that i am programming from scratch (no particle software) but am stuck getting the connection between the nrf52840 and the SARA U201 working.
I have two particular questions that I hope someone can help with.
Should I expect the uart baud rate to be 115200 (factory default) or 921600 (as used in particle firmware)?
Is there a way to enable DTR (drive it low) which is what I think the modem needs to work? I cannot see how to do this from the schematic but is required as described in the Ublox system integration manual.