nRF9160 AT interface UART hardware related

[Smart.Enrg]

Hi,

I'm trying to make provision for AT command interface in my new nRF9160-SiP based design.

Couple of questions related to that:

1) Which UART (nRF9160-SiP pins) should I be using for this purpose? Also - are handshake
    (RTS, CTS, etc) lines absolutely needed for AT interface use. If possible,I would rather use
     RX,TX only.

2)  I understand firmware for this pre-production part is very much evolving right now. So, I'm 
     wondering what LTE, GPS functions are currently supported, which ones are on roadmap 
     for release in near future. I'm trying to evaluate what I lose by going AT interface vs. full 9 
     line (nRF52840) co/processor functionality; is there any feature set comparison available?

Please advise. Thanks.

Best,
Ash

[Martin Lesund]

Hi Ash,

1) The AT Host library lets you choose which UART to use.
As default it is UART0 and the pins can be any of the GPIOs. 

For the nRF91 DK for example, the UART0 is using the pins P0.26, P0.27, P0.28, and P0.29 and they are routed to VCOM0.

The RTS, CTS lines are not absolutely needed, but usually recommended. 

2) Please refer to the Development Status page on what is supported and what is coming.

Please note that the nRF9160 SIP in not just a modem.

It has its own Microcontroller with the ARM Cortex M33++, Product Specification.

The only functionality you would lose if you do not want to interface the nRF9160 SIP with a nRF52840 chip is typical BLE which the nrf52 has.