Hi all,
I'm working on a project involving UART communication over RS-485 between an STM32 Nucleo board and a rotary encoder. I'd appreciate any advice or insights on whether my hardware and firmware setup looks correct, and what to check next to ensure reliable communication.
Board: STM32 Nucleo-L476RG
Encoder: 6-pin rotary encoder with the following pinout:
Pin 1: 5V
Pin 2: B
Pin 3: A
Pin 4: GND
Pin 5: MODE
Pin 6: MCLR
RS-485 Transceiver: MAX485-compatible module
RO (Receiver Out) → PA10 (USART1_RX)
DI (Driver In) → PA9 (USART1_TX)
RE (Receiver Enable) → PB3
DE (Driver Enable) → PB4
VCC: 3.3V (from Nucleo 3.3V)
GND: common with Nucleo and encoder
- A ---> Encoder Pin A
- B ---> Enocder Pin B
PC Interface:
I'm using a USB cable from the laptop to the Nucleo, which powers the board and also uploads code.
USART2 is used for debug printouts via USB virtual COM port (seen in PuTTY).
USART1 is used for RS-485 communication
I believe my issue is in the software. How do I get communication?
Here are the datasheets:
Encoder: https://www.sameskydevices.com/product/resource/amt21.pdf
