Nova LTE direct UART connection

[curve514]

This post would have been in reply to this closed thread:

Using UART on a brand new Nova Global Cellular Modem

Hi There! I just received my brand new and fresh Nova Global where the main modem is an Ublox SARA-R410 and I am planning to use the UART interface instead of USB to issue AT commands. Reading a bit more on the https://hologram.io/docs/reference/nova/datasheet/ _ The USB_D+ / USB_D- lines carry the USB serial data and signaling. The USB interface is automatically enabled by an external valid USB VBUS supply voltage (5.0 V typical) applied on the VUSB_DET pin. _ and also Ublox SARA-R410 d…

Minding the level shifters to 1.8V logic, you only need to “scrape-off” one via to gain direct uart communication to the Nova LTE board. Removing top layer of the via just left to the RESET solder pad will disable USB communication. With basic magnification an a sharp x-acto blade, this is a relatively quick and easy job.

Also, the module will work with direct Li-Ion voltage power on USB VCC pin. (Be sure to have low-ESR cap at the mating USB connector.) No need to remove regulator.

Disclaimer : This post is only intended to people using Hologram hardware as engineering testing shortcuts. Waiving any warranty or liability to the manufacturer. (Duh!)

J.