- \n
- Raspberry Pi B+ V1.2<\/li>\n<\/ul>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/1-300x195.png\")
<\/p>\n- \n
- Arduino UNO<\/li>\n<\/ul>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/2-300x199.png\")
<\/p>\n- \n
- Flame sensor<\/li>\n<\/ul>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/3.png\")
<\/p>\n- \n
- Semtech SX1276RF1IAS with antenna<\/li>\n<\/ul>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/4-300x147.png\")
<\/p>\nSetting up the TX side<\/strong><\/span><\/h3>\n
Tx side is composed of Arduino UNO, SX1276RF1IAS module and flame sensor.<\/p>\n
<\/p>\n
Step1:<\/strong> Wire all the parts mentioned above according to this table:<\/p>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/5-222x300.png\")
<\/p>\nSCK, MISO, MOSI, NSS and NRESET are pins that are always used for wiring ordinary SX1276 chip to Arduino board. RXTX, FEM_CTX and FEM_CPS are pins that are used specifically with SX1276RFIAS module.<\/p>\n
Note that you need to connect all three pins used for power supply –\u00a0 VDD_RF,VDD_ANA, VDD_FEM and all three GROUND pins too. Since Arduino UNO only has one 3.3V pin, you need to use something that allows you to connect these three power supply pins to Arduino 3.3V port. I used \u201ebread board\u201c which allows you to split one port to multiple ports. Another option is to use external power supply.<\/p>\n
If you connected it properly, your Tx side should look like this:<\/p>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/6-300x155.png\")
<\/p>\n<\/p>\n
Step 2:<\/strong> Download Arduino IDE, connect Arduino UNO to PC and setup your IDE.<\/p>\n
You can find Arduino IDE here: https:\/\/www.arduino.cc\/en\/software<\/a><\/p>\n
Connect your Arduino UNO to PC and open Arduino IDE. Then, you need to set used Port. You can do this by clicking \u201eTools\u201c -> \u201ePort\u201c -> choose COM5.<\/p>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/7-300x172.png\")
<\/p>\nYou can now upload code included below (or write your own). Here I will highlight main parts of the code and explain them.<\/p>\n
Code for Tx side: https:\/\/wtools.io\/paste-code\/b4G5<\/a><\/p>\n
<\/p>\n
I am using Arduino LoRa library by sandeepmistry (\u00a0https:\/\/github.com\/sandeepmistry\/arduino-LoRa <\/a>).<\/p>\n
#include <SPI.h>\r\n#include <LoRa.h>\r\n#define analogPin A0 \/\/flame sensor pin\r\nint flame;\r\nint counter = 0;\r\n\r\nvoid setup() { \r\nSerial.begin(9600);\r\npinMode(analogPin, INPUT); \/\/ inicialization of flame sensor\r\n\r\nwhile (!Serial);\r\nSerial.println(\"LoRa Sender\");\r\nif (!LoRa.begin(169E6)) { \/\/input your frequency - 169 MHz\r\nSerial.println(\"Starting LoRa failed!\");\r\nwhile (1);\r\n}\r\n\/\/below are optional parameters for LoRa transmitter\r\n\/\/use the same for Tx and Rx side\r\nLoRa.setTxPower(10);\r\nLoRa.setSpreadingFactor(7); \r\nLoRa.setSignalBandwidth(125E3); \r\nLoRa.setCodingRate4(5);\r\n\r\npinMode(4, OUTPUT); \r\npinMode(6, OUTPUT); \r\npinMode(7, OUTPUT); \r\ndigitalWrite(4, LOW); \/\/FEM_CPS=0\r\ndigitalWrite(6, LOW); \/\/FEM_CTX=0\r\ndigitalWrite(7, HIGH); \/\/RXTX=1 (means it is transmitting)\r\n\r\nSerial.println(\"setup complete\");\r\n}<\/pre>\nFirst I defined analog pin for Flame sensor. In setup() function you need to set the flame sensor\u00b4s pin as an input.\u00a0 Following code for LoRa initialization can be found and explained in LoRa library\u00b4s documentation mentioned earlier.<\/p>\n
LoRa.begin(169E6) begins the communication on 169 MHz. If you want to use another frequency, you can change it right here, but just make sure your module supports your frequency (our used module supports 169 and 868 MHz). If you had the module connected incorrectly, you would see \u201eStarting LoRa failed!\u201c in output window.<\/p>\n
Next you can set Tx parameters \u2013 like TxPower, SF, bandwidth, coding rate and more. All parameters that you can set can be found in this library\u00b4s documentation.<\/p>\n
What makes the work with this module different from ordinary SX1276 chip are 3 pins –\u00a0 FEM_CPS, FEM_CTX and RXTX. You need to set them properly to get the module working. Because we want to transmit on LOW frequency we need to set FEM_CPS=0, FEM_CTX=0 and RXTX=1 (meaning that we want to transmit).<\/p>\n
If you want to transmit on HIGH frequency, you need to set FEM_CPS=0, FEM_CTX=1 and RXTX=1.<\/p>\n
Now, you can set these three pins by using digitalWrite function \u2013 LOW means 0, HIGH means 1.<\/p>\n
void loop() {\r\nint voltageSensor = analogRead(analogPin); \/\/load flame sensor pin\r\nint flame = map(voltageSensor, 0, 1024, 0, 3); \r\n\/\/0 = flame is close\r\n\/\/1= there is flame nearby\r\n\/\/2=no flame detected \r\n\r\nSerial.print(\"Sending packet: \");\r\nSerial.println(counter);\r\nSerial.println(\"Flame: \");\r\nSerial.println(flame);\r\n\r\nLoRa.beginPacket(); \/\/start the packet\r\nLoRa.print(flame); \/\/data of the packet - flame\r\nLoRa.endPacket(); \/\/end the packet\r\n\r\ncounter++;\r\ndelay(1000);\r\n}<\/pre>\nIn loop function, read the value of flame sensor\u00b4s analog pin and convert it to value between <0,2>.<\/p>\n
Then LoRa.beginPacket() begins the packet and LoRa.endPacket ends the packet. Between these two lines you can insert data in this packet -> in this code we insert mentioned variable –\u00a0 \u201eflame\u201c.<\/p>\n
<\/p>\n
Step 3<\/strong>: Try to start your Tx side<\/p>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/10-300x208.png\")
<\/u><\/p>\nYou can upload your code to Arduino by clicking first on \u201eA\u201c button which checks the code for possible error and then clicking on \u201eB\u201c button to upload your code. However, that is not all, you need to view and check the output of the code by clicking \u201eTools\u201c -> \u201eSerial Monitor\u201c.<\/p>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/11-300x207.png\")
<\/p>\nIf there is everything set up and wired correctly, you should see this output:<\/p>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/12-300x132.png\")
<\/p>\nEach second, the transmitter transmits data and tells us, if there is a flame nearby or not.<\/p>\n
Setting up the RX side<\/span><\/strong><\/h3>\n
Rx side is composed of Raspberry Pi and SX1276RF1IAS module.<\/p>\n
- Semtech SX1276RF1IAS with antenna<\/li>\n<\/ul>\n
- Flame sensor<\/li>\n<\/ul>\n
- Arduino UNO<\/li>\n<\/ul>\n
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/13-300x98.png\")
<\/p>\n![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/14-300x120.png\")
<\/p>\n![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/15-300x212.png\")
<\/p>\n![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/16-134x300.png\")
<\/p>\n![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/17-300x175.png\")
<\/p>\n![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/21-300x153.png\")
<\/p>\n![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/22-300x190.png\")
<\/p>\n![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/25-176x300.png\")
![\"\"](\"http:\/\/lora.vsb.cz\/wp-content\/uploads\/2021\/05\/24.png\")
<\/p>\n","protected":false},"excerpt":{"rendered":"