Answer
The Vela IF820 exposes to UARTS.
- UART 0 also known as the HCI UART
- UART 1the EZ-Serial UART (115200,8N1 no flow control)
On booting a Vela IF820 loaded with EZ-Serial Firmware a boot message will be sent on UART 1 and will look something like this
@E,0074,BOOT,E=01040808,S=03010000,P=0104,H=23,C=00,A=E77BCEF68661,F=EZ-Serial-CYBT_243053_02 V1.4.8.8 Jun 9 2023 10:03:25
Firmware updates should be performed on UART 0
Firmware and flashing tools can be downloaded from https://github.com/LairdCP/Vela_IF820_Firmware/releases