2025-06-18 2:17 AM
Hi, I am working on configuring LoRa (E22-900M22S) and the MAX3485 transceiver to establish RS-485 communication using the STM32H753ZI. I have connected the LoRa and MAX3485 modules as per the following reference:
LoRa(E22-900M22S) | |
LoRa Pin | STM32H753ZI Pin (example) |
MOSI | PA7 (SPI1_MOSI) |
MISO | PA6 (SPI1_MISO) |
SCK | PA5 (SPI1_SCK) |
NSS | PA4 (GPIO) |
RESET | PB0 (GPIO) |
DIO1 | PB1 (EXTI-capable GPIO) |
DIO2 | PB2 (EXTI-capable GPIO) |
BUSY | PB10 (GPIO input) |
GND | GND |
VCC | 3.3V |
RS-485(MAX3485) | |
STM32H753ZI Pin | MAX3485 Pin |
PD8 | DI |
PD9 | RO |
PD12 (or any GPIO with DE support) | DE + RE (tied together) |
3.3V | VCC |
GND | GND |
Could you please guide me on how to configure both LoRa and RS-485 communication using STM32CubeIDE?
2025-06-18 3:53 AM - edited 2025-06-18 3:53 AM
A schematic is a better way to present an electronic circuit.
I'm not clear if you mean that the H7 is connected to the E22 LoRa via RS485, or if these are two separate interfaces?