Moorthy Muthukrishnan / Mbed 2 deprecated Ultrasonic_HC-SR04_New

Translated comments into English. Added serial display through PC using TeraTerm

Dependencies:   TextLCD mbed

Fork of Ultrasonico_HC-SR04 by Icaro Brito

main.cpp@1:0244dd451883, 2015-07-14 (annotated)

Committer:
nmoorthy2001
Date:
Tue Jul 14 09:32:34 2015 +0000
Revision:
1:0244dd451883
Parent:
0:34f7d9ef2f4b 
Translated the comments into English

Who changed what in which revision?

UserRevisionLine numberNew contents of line
nmoorthy2001 1:0244dd451883 1 /* Program for using Ultrasonic Sensor - Modified by Moorthy Muthukrishnan.
nmoorthy2001 1:0244dd451883 2 April 2015. */
nmoorthy2001 1:0244dd451883 3 /* Trigger is supplied through Port E, Pin 5 for sending the pulse
nmoorthy2001 1:0244dd451883 4 Uses interrupt in Port A, pin 16 to determine the pulse width */
icarobrito 0:34f7d9ef2f4b 5
icarobrito 0:34f7d9ef2f4b 6 #include "mbed.h"
nmoorthy2001 1:0244dd451883 7 #include "TextLCD.h"
icarobrito 0:34f7d9ef2f4b 8
nmoorthy2001 1:0244dd451883 9 Serial pc(USBTX,USBRX); //Serial port to communicate with the PC
nmoorthy2001 1:0244dd451883 10 TextLCD lcd(PTA13, PTD5, PTD0, PTD1, PTD2, PTD3, TextLCD::LCD16x2); // RS, E, D4-D7
nmoorthy2001 1:0244dd451883 11 DigitalOut trig(PTE5,0); //Configuring the pin for Trigger
nmoorthy2001 1:0244dd451883 12 InterruptIn echo(PTA16); //Configuring the pin for Echo
nmoorthy2001 1:0244dd451883 13 Timer temp;
nmoorthy2001 1:0244dd451883 14 float tdist=0, distcm=0, distin=0, dist0=0;
icarobrito 0:34f7d9ef2f4b 15
nmoorthy2001 1:0244dd451883 16 // Function for starting the timer to mark the first edge of echo
nmoorthy2001 1:0244dd451883 17 void iniP()
nmoorthy2001 1:0244dd451883 18 {
nmoorthy2001 1:0244dd451883 19 temp.start();
nmoorthy2001 1:0244dd451883 20 return;
nmoorthy2001 1:0244dd451883 21 }
nmoorthy2001 1:0244dd451883 22
nmoorthy2001 1:0244dd451883 23 //Function for stopping the timer to mark the end of echo pulse
nmoorthy2001 1:0244dd451883 24 void finP()
nmoorthy2001 1:0244dd451883 25 {
nmoorthy2001 1:0244dd451883 26
nmoorthy2001 1:0244dd451883 27 tdist = temp.read_us(); //Read the timer in Microseconds
nmoorthy2001 1:0244dd451883 28 distcm = tdist/58; //Calculate the distance in "cm"
nmoorthy2001 1:0244dd451883 29 distin = tdist/148; //Calculate the distance in "inch"
icarobrito 0:34f7d9ef2f4b 30
nmoorthy2001 1:0244dd451883 31 temp.stop(); //Stop the timer
nmoorthy2001 1:0244dd451883 32 temp.reset(); //Reset the timer
nmoorthy2001 1:0244dd451883 33 return;
nmoorthy2001 1:0244dd451883 34 }
nmoorthy2001 1:0244dd451883 35
nmoorthy2001 1:0244dd451883 36 int main()
nmoorthy2001 1:0244dd451883 37 {
nmoorthy2001 1:0244dd451883 38 pc.printf("Starting the Distance sensor\n");
nmoorthy2001 1:0244dd451883 39 lcd.locate(0, 0);
nmoorthy2001 1:0244dd451883 40 lcd.printf("Distance sensor\n");
icarobrito 0:34f7d9ef2f4b 41
nmoorthy2001 1:0244dd451883 42 while(1)
nmoorthy2001 1:0244dd451883 43 {
nmoorthy2001 1:0244dd451883 44 trig=1; //make the trigger = 1
nmoorthy2001 1:0244dd451883 45 wait_us(10); // 10us pulse
nmoorthy2001 1:0244dd451883 46 trig=0; //Make trigger = 0
icarobrito 0:34f7d9ef2f4b 47
nmoorthy2001 1:0244dd451883 48 echo.rise(&iniP); //Rising edte of the pulse
nmoorthy2001 1:0244dd451883 49 echo.fall(&finP); //Falling edge of the pulse
icarobrito 0:34f7d9ef2f4b 50
nmoorthy2001 1:0244dd451883 51 // display the distance in cm
nmoorthy2001 1:0244dd451883 52 if(distcm != dist0)
nmoorthy2001 1:0244dd451883 53 {
nmoorthy2001 1:0244dd451883 54 dist0 = distcm;
nmoorthy2001 1:0244dd451883 55 if (distcm < 3000.0)
nmoorthy2001 1:0244dd451883 56 {
nmoorthy2001 1:0244dd451883 57 pc.printf("Distance detected by the sensor %.2f cm \n\n",distcm);
nmoorthy2001 1:0244dd451883 58 lcd.locate(0,1);
nmoorthy2001 1:0244dd451883 59 lcd.printf("Distance=%.2fcm\n", distcm);
icarobrito 0:34f7d9ef2f4b 60 }
nmoorthy2001 1:0244dd451883 61 else
nmoorthy2001 1:0244dd451883 62 {
nmoorthy2001 1:0244dd451883 63 pc.printf("Error in distance measurement \n\n");
nmoorthy2001 1:0244dd451883 64 lcd.locate(0,1);
nmoorthy2001 1:0244dd451883 65 lcd.printf("Error\n");
nmoorthy2001 1:0244dd451883 66 }
icarobrito 0:34f7d9ef2f4b 67 }
nmoorthy2001 1:0244dd451883 68 wait_ms(3000); //Wait before sending the next pulse
nmoorthy2001 1:0244dd451883 69 }
icarobrito 0:34f7d9ef2f4b 70
nmoorthy2001 1:0244dd451883 71 }
nmoorthy2001 1:0244dd451883 72
nmoorthy2001 1:0244dd451883 73 // End of main