Setup HOWTO

InAir4 Setup

[InAir4-Pinouts](##InAir4 Pinouts)

The InAir4 module is manufactuered by Modtronix, and with a Semtech SX1278 (SX1276) LoRa Module, set to 433MHz, 3.3V input, SMA Connector. Modtronix has a range of antennas that can be used with the LoRa module that are avialable as well.

http://modtronix.com/inair4.html

The pins are labelled as follows. Make sure that the model is inAir4 - this should be printed on the PCB.

()		()
GND		NC
CS		3.3V
DIO3		SCK
RST		MISO
DIO0		MOSI
DIO1		NC
DIO2		VSWITCH

[Pinout-Description](###Pinout Description)

Label	Function
GND	Ground PIN
CS	Chip Select
DIO3	Digital Input / Output (3)
RST	Reset Pin
DIO0	Digital Input / Output (0)
DIO1	Digital Input / Output (1)
DIO2	Digital Input / Output (2)
NC	Not Connected
3.3V	Vin, 3.3VDC
SCK	SPI Clock
MISO	SPI MISO
MOSI	SPI MOSI
NC	Not Connected
VSWITCH	VSWITCH

[Module-Image](###Module Image)

[Bottom-View](###Bottom View)

[Pin-Layout](###Pin Layout)

Schmatic

[Setup](##Setting up the LoRa InAir4 Module with Arduino Pro Micro)

The example code in this repo using GPIOs that can be configured accordingly, here we are using the Arduino Pro Micro.

To keep things simple the pins are wired as follows:

ProMicro	()		()	ProMicro
GND	GND		NC
18	CS		3.3V	3.3VDC
	?		SCK	SCK
21	RST		MISO	MISO
	?		MOSI	MOSI
	?		NC
20	DIO2		VSWITCH	3.3VDC

This can be found in the example code where the pins are configured as follows:

SCK 15

MOSI 16

MISO 14

RESET 21

DIO0 20

NSEL 18

LED 19

[ConOps](##Concept of Operation)

There are two Arduino Pro Micros, each with a InAir4 module connected as per the pinouts above. One should be programmed as the lora-client and one should be programmed as the lora-server.

There are two ways to monitor the inAir4 modules,

1. Through the USB serial port, 9600 8N1 or
2. Through the console port. This is using a USB <--> 3.3V level cable, connected to pins 1,2 & GND

The code can be easily altered to have hte debug messages come to the serial instead of the console . A simple find and replace can make this change.

Registers

On power up there is some communication back and forth between the arduino and the inAir4. This can be used to confirm that the power is wired correctly and the SPI interface is functioning.

Config

sx1278_Config() sets all the registers as requried. Just about everything is fixed - including the frequency at 433Mhz. Before changing any settings its recommended that the two units are tested at short range with the default settings.

Setup-function

After config it goes to sx1278_Setup() which configures all the GPIO pins. This is self explanatory.

Loop-function

In the main loop the code will force the lora-client into RX_continuous mode, and the lora-server into TX mode. An arbitary message is loaded into the TX buffer that should be sent out the first time around then after a shortly delay the TX buffer is rewritten with the alphabest.

The contains of the opmode register and RX buffer are continually output, so all changes to the data transmission should be seen there.