/*
 This program is the interpretation routine of standard output protocol of TFmini-Plus product on Arduino.
 For details, refer to Product Specifications.
 For Arduino boards with only one serial port like UNO board, the function of software visual serial port is
to be used.
*/
#include <SoftwareSerial.h> //header file of software serial port
SoftwareSerial Serial1(3,2); //define software serial port name as Serial1 and define pin2 as RX and pin3 as TX
  /* For Arduinoboards with multiple serial ports like DUEboard, interpret above two pieces of code and
  directly use Serial1 serial port*/
  int dist; //actual distance measurements of LiDAR
  int strength; //signal strength of LiDAR
  float temprature;
  int check; //save check value
  int i;
  int uart[9]; //save data measured by LiDAR
  const int HEADER=0x59; //frame header of data package

void setup() {
  Serial.begin(9600); //set bit rate of serial port connecting Arduino with computer
  Serial1.begin(115200); //set bit rate of serial port connecting LiDAR with Arduino
}


void loop() {
   if (Serial1.available()) { //check if serial port has data input
   if(Serial1.read() == HEADER) { //assess data package frame header 0x59
   uart[0]=HEADER;
   if (Serial1.read() == HEADER) { //assess data package frame header 0x59
   uart[1] = HEADER;
   for (i = 2; i < 9; i++) { //save data in array 
   uart[i] = Serial1.read();
 }
       check = uart[0] + uart[1] + uart[2] + uart[3] + uart[4] + uart[5] + uart[6] + uart[7];
       if (uart[8] == (check & 0xff)){ //verify the received data as per protocol
       dist = uart[2] + uart[3] * 256; //calculate distance value in cm
       strength = uart[4] + uart[5] * 256; //calculate signal strength value
       temprature = uart[6] + uart[7] *256;//calculate chip temprature
       temprature = temprature/8 - 256;
       Serial.print("dist = ");
       Serial.print(dist); //output measure distance value of LiDAR
       Serial.print('\t');
       Serial.print("strength = ");
       Serial.print(strength); //output signal strength value
       Serial.print("\t Chip Temprature = ");
       Serial.print(temprature);
       Serial.println(" celcius degree"); //output chip temperature of Lidar
      }
    }
  }
 }
}