Configure LoRa E22-900M22s module and MAX3485 (for Rs485) into STM32H753ZIT6

[Ematic]

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?

[Andrew Neil]

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?

[Ematic]

Hi @Andrew Neil, in response to your concern, I’ve shared the schematic diagram. Please note that the E22 LoRa and MAX485 (RS485) modules are separate interfaces.

 

[Andrew Neil]

You've marked by previous reply as The Solution - but it was really just a question.

Are you saying that you've now resolved the problem?

If not, here are instructions to un-mark it.

 

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@Ematic wrote:

the E22 LoRa and MAX485 (RS485) modules are separate interfaces.

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So just handle them separately:

1. the E22 LoRa does not depend on the RS485 - it's just the same as any other E22 LoRa application
    
2. the RS485 does not depend on the E22 LoRa - it's just the same as any other RS485 application

 

Note that the E22 is a third-party product - not ST - so you should go to Ebyte for support with that: 

https://www.cdebyte.com/products/E22-900M22S