STM32F446VET7 LoRa E220-400T30S UART Communication
Hello,
I am trying write a LoRa library to STM32F446VET7 in my application.
In the LoRa E220-400T30S documentation, it tells me to set the UART settings for configuration mode to 9600 and 8N1 and to give 1 to M0 - M1 pins.

After doing that I am trying an exampe in below of the document

I am sending "C10004" and I have an interrupt for receive function for RX. But I got nothing in buffer...



I'm using UART for the first time, so I can't even guess what I'm doing wrong. I would be very grateful if you can help me.
