This is a breakout board for the SX1280 in Arduino form-factor to use with e.g. STM32 Nucleo Dev Boards or similar. It uses the E28-2G4M12S module from EBYTE, which is readily available from AliExpress or Banggod.
The official SX1280 shield (SX1280RF1ZHP) from the Semtech's SX1280DVK1ZHP or SX1280ED1ZHP development kits have resistors in the SPI lines, which limit the SPI speed to about 5 Mhz.
While SPI speed is not relevant for LoRa operations, implementing Bluetooth Low Energy requires to transfer data packets to/from the SX1280 quickly, which is easier to achieve with the max SPI speed of 18 Mhz. This breakout board was created to avoid replacing the resistors with 0 Ohm ones on the official shield and to allow the full 18 Mhz SPI speed.
| Signal | Arduino | Debug connector |
|---|---|---|
| 3V3 | 3V3 | |
| GND | GND | 1 |
| NSS | D7 | 2 |
| SCK | SCK | 3 |
| MOSI | MOSI | 4 |
| MISO | MISO | 5 |
| BUSY | D3 | 6 |
| DIO1 | D5 | 7 |
| DIO2 | 8 | |
| DIO3 | 9 | |
| nReset | A0 | 10 |
All signals are provided at the J1 debug connector to hook up a logic analyzer.
The SX1280 can map various IRQ requests on the DIO1-3 pins. DIO1 is pre-assigned in this shield, while the DIO2 and DIO3 can be connected via jumper J2 to other GPIO pins if needed.
Please note: The SX1280 is not 5V tolerant.
