HamShield: LoRa Edition Pinouts

HamShield: LoRa Edition is compatible with both Arduino and Raspberry Pi, allowing for a lot of different connection options. This article will discuss connected pins, as well as various GPIO options you can implement.

The shield features 5V to 3.3V level shifters for Arduino Uno operation, and directly connected 3.3V logic for the Raspberry Pi, which is a 3.3V system.

Arduino Uno Pinouts

HamShield: LoRa Edition uses SPI to communicate with the SX1276 within the LoRa module. There are also additional GPIO lines to handle functions like packet interrupts as well as a chip select line. All other Arduino pins are passthrough and are not interfered with.

 

 Pin Purpose Description
D2 DIO0 Multi-purpose GPIO from radio, typically used for incoming packet interrupts
D3 Radio Reset Used to reset the radio
D10 SS Chip select
D11 MOSI Master Out, Save In (SPI data line)
D12 MISO Master In, Slave Out (SPI data line)
D13 SCK Clock (SPI clock line)

 

Raspberry Pi Pinouts

The Raspberry Pi interface is a basic Hat interface that does not feature a configuration EEPROM.

SPI1 is used for communication between the Raspberry Pi and the SX1276, and two additional GPIOs are used to handle incoming packet interrupts and chip reset. Each pin number corresponds to the pin number on the 2x20 40 pin header.

 Pin Purpose Description
19 MOSI Master Out, Slave In (SPI data line)
21 MISO Master In, Slave Out (SPI data line)
23 SCK Clock (SPI Clock Line)
24 SS Chip select for SX1276

 

Additional GPIO Access

The SX1276 provides a bank of 5 additional GPIOs (D1-D5), which can be configured for a variety of functions. While not typically used in standard LoRa libraries, there are some powerful features that can be accessed by the more advanced user. 

GPIOs D1-D5 are available at two voltages: 3.3V and 5V. The 5V voltages are levelshifted down to 3.3V, making them useful for 5V microcontrollers, such as the Arduino Uno. 3.3V GPIOs are directly connected into the SX1276.

LL-3V3 are 3.3 volt lines. LL-5V are 5 volt lines.

Please note that you must use the correct voltage for your system, otherwise, it can damage your HamShield: LoRa Edition.

We advise using a small gauge "green wire" to access these breakout pins, or soldering headers and using jumper wire.