Neil Johnson / Mbed 2 deprecated ScalextricTimer

Scalextric Lap Timer using ultrasonic sensor

Dependencies:   HCSR04 mbed TextLCD

main.cpp@3:389e402bd42f, 2017-10-09 (annotated)

Committer:
MrBedfordVan
Date:
Mon Oct 09 17:24:44 2017 +0000
Revision:
3:389e402bd42f
Parent:
2:b47f8dbf374c 
Added stability and display distance for debug as it runs

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MrBedfordVan 1:034f79c00c98 1 // Scalextric Timer for Ada Lovelace Day
MrBedfordVan 1:034f79c00c98 2 //
MrBedfordVan 1:034f79c00c98 3 // Uses Nucleo board F072 with LCD Keypad shield
MrBedfordVan 1:034f79c00c98 4 // Connect D3 to Trig & D2 to Echo
MrBedfordVan 1:034f79c00c98 5 // Connect VCC to 5V (pin CN7 18)
MrBedfordVan 1:034f79c00c98 6 // Connect GND to 0V (pin CN7 19)
MrBedfordVan 1:034f79c00c98 7
MrBedfordVan 0:b88af2ed370b 8 #include "mbed.h"
MrBedfordVan 1:034f79c00c98 9 #include "hcsr04.h" // Ultrasonic sensor
MrBedfordVan 1:034f79c00c98 10 #include "TextLCD.h" // LCD1602
MrBedfordVan 0:b88af2ed370b 11
MrBedfordVan 1:034f79c00c98 12 // serial PC for debug
MrBedfordVan 3:389e402bd42f 13 //Serial pc(SERIAL_TX, SERIAL_RX);
MrBedfordVan 1:034f79c00c98 14 // Ultrasonic sensor
MrBedfordVan 3:389e402bd42f 15 HCSR04 usensor(D3,D2); // Trig, Echo - locks sometimes
MrBedfordVan 1:034f79c00c98 16
MrBedfordVan 1:034f79c00c98 17 // LCD Shield
MrBedfordVan 1:034f79c00c98 18 TextLCD lcd(D8, D9, D4, D5, D6, D7); // used to drive display
MrBedfordVan 3:389e402bd42f 19 //AnalogIn keys(A0); // used to sample buttons
MrBedfordVan 1:034f79c00c98 20
MrBedfordVan 1:034f79c00c98 21 Timer lap_timer;
MrBedfordVan 1:034f79c00c98 22
MrBedfordVan 2:b47f8dbf374c 23 // Subroutine to display text on LCD - called from below
MrBedfordVan 2:b47f8dbf374c 24 // call as follows:
MrBedfordVan 2:b47f8dbf374c 25 // textLCD(text, line)
MrBedfordVan 2:b47f8dbf374c 26 // where text = up to 16 characters of text
MrBedfordVan 2:b47f8dbf374c 27 // line = line 0 or 1 on the LCD; where 0 is the top line and 1 is the bottom line
MrBedfordVan 2:b47f8dbf374c 28
MrBedfordVan 1:034f79c00c98 29 void textLCD(char *text, int line) {
MrBedfordVan 2:b47f8dbf374c 30
MrBedfordVan 3:389e402bd42f 31 char tmpBuf[16];
MrBedfordVan 3:389e402bd42f 32 for (int i = 0; i < 14; i++) {
MrBedfordVan 3:389e402bd42f 33 if (i < strlen(text)) {
MrBedfordVan 3:389e402bd42f 34 tmpBuf[i] = text[i];
MrBedfordVan 3:389e402bd42f 35 }
MrBedfordVan 3:389e402bd42f 36 else
MrBedfordVan 3:389e402bd42f 37 {
MrBedfordVan 3:389e402bd42f 38 tmpBuf[i] = 0x20;
MrBedfordVan 3:389e402bd42f 39 }
MrBedfordVan 1:034f79c00c98 40 lcd.locate(i, line);
MrBedfordVan 1:034f79c00c98 41 lcd.putc(tmpBuf[i]);
MrBedfordVan 1:034f79c00c98 42 }
MrBedfordVan 1:034f79c00c98 43 }
MrBedfordVan 1:034f79c00c98 44
MrBedfordVan 3:389e402bd42f 45 // Subroutine to display Lap data on LCD - called from below
MrBedfordVan 3:389e402bd42f 46 // call as follows:
MrBedfordVan 3:389e402bd42f 47 // DisplayLap(lap_count, dist, lap_time, Show_Time);
MrBedfordVan 3:389e402bd42f 48
MrBedfordVan 3:389e402bd42f 49 void DisplayLap(int lcl_lap_count, int lcl_dist, float lcl_lap_time, bool Show_Time) {
MrBedfordVan 3:389e402bd42f 50
MrBedfordVan 3:389e402bd42f 51 char lap_string[16];
MrBedfordVan 3:389e402bd42f 52 char lap_string2[16];
MrBedfordVan 3:389e402bd42f 53 //textLCD("1 ", 0); // Clear top line on LCD
MrBedfordVan 3:389e402bd42f 54 //textLCD("2 ", 1); // Clear bottom line on LCD
MrBedfordVan 3:389e402bd42f 55 //lcd.cls();
MrBedfordVan 3:389e402bd42f 56
MrBedfordVan 3:389e402bd42f 57 int lcl_lap_time_integerPart = (int)lcl_lap_time;
MrBedfordVan 3:389e402bd42f 58 int lcl_lap_time_decimalPart = ((int)(lcl_lap_time*1000)%1000);
MrBedfordVan 3:389e402bd42f 59
MrBedfordVan 3:389e402bd42f 60 sprintf(lap_string, "Lap : %d D : %d", (char*)lcl_lap_count, (char*)lcl_dist); // Format Lap count string
MrBedfordVan 3:389e402bd42f 61 // pc.printf("%s \n\r", lap_string);
MrBedfordVan 3:389e402bd42f 62 textLCD("1 ", 0); // Clear top line on LCD
MrBedfordVan 3:389e402bd42f 63 textLCD(lap_string, 0); // Display distance on LCD
MrBedfordVan 3:389e402bd42f 64
MrBedfordVan 3:389e402bd42f 65 if (Show_Time) {
MrBedfordVan 3:389e402bd42f 66 sprintf(lap_string2, "Time : %d.%d s, ", (char*)lcl_lap_time_integerPart, (char*)lcl_lap_time_decimalPart); // Format Lap time string
MrBedfordVan 3:389e402bd42f 67 // pc.printf("%s \n\r", lap_string);
MrBedfordVan 3:389e402bd42f 68 textLCD("1 ", 1); // Clear bottom line on LCD
MrBedfordVan 3:389e402bd42f 69 textLCD(lap_string2, 1); // Display Lap Time on LCD
MrBedfordVan 3:389e402bd42f 70 }
MrBedfordVan 3:389e402bd42f 71 }
MrBedfordVan 3:389e402bd42f 72
MrBedfordVan 2:b47f8dbf374c 73 ///////////////////////////////////////////////////////////////////////////////
MrBedfordVan 2:b47f8dbf374c 74 // Main Program starts here
MrBedfordVan 2:b47f8dbf374c 75 ///////////////////////////////////////////////////////////////////////////////
MrBedfordVan 0:b88af2ed370b 76
MrBedfordVan 0:b88af2ed370b 77 int main()
MrBedfordVan 0:b88af2ed370b 78 {
MrBedfordVan 2:b47f8dbf374c 79
MrBedfordVan 2:b47f8dbf374c 80 //// Try changing these:
MrBedfordVan 2:b47f8dbf374c 81 // Variables to tune
MrBedfordVan 2:b47f8dbf374c 82 float min_laptime = 1.0; // Minimum laptime - time to wait after seeing car before measuring again in seconds
MrBedfordVan 3:389e402bd42f 83 int sample_time = 500; // Sample time - time between sampling values from sensor in milliseconds
MrBedfordVan 3:389e402bd42f 84 int trigger_distance = 5; // Trigger distance - distance below which the car registers as detected
MrBedfordVan 2:b47f8dbf374c 85 //// Careful with anything after this though
MrBedfordVan 2:b47f8dbf374c 86
MrBedfordVan 2:b47f8dbf374c 87 // Variables used within the program - set to their initial values
MrBedfordVan 0:b88af2ed370b 88 int dist = 0;
MrBedfordVan 3:389e402bd42f 89 float lap_time = 0.0;
MrBedfordVan 1:034f79c00c98 90 int lap_count = 0;
MrBedfordVan 3:389e402bd42f 91
MrBedfordVan 0:b88af2ed370b 92
MrBedfordVan 2:b47f8dbf374c 93 // Initialise the serial interface and set its data rate
MrBedfordVan 3:389e402bd42f 94 // pc.baud(9600);
MrBedfordVan 0:b88af2ed370b 95
MrBedfordVan 1:034f79c00c98 96 // Intro Screen
MrBedfordVan 3:389e402bd42f 97 // pc.printf("ARM Sheffield Scalextric Challenge \n"); // Display to Serial Interface
MrBedfordVan 2:b47f8dbf374c 98 textLCD("ARM Scalextric ", 0); // Display on First Line of LCD
MrBedfordVan 3:389e402bd42f 99 wait_ms(2000); // Wait 2s
MrBedfordVan 3:389e402bd42f 100 textLCD(" ", 0); // Clear top line on LCD
MrBedfordVan 1:034f79c00c98 101
MrBedfordVan 3:389e402bd42f 102 // Main loop - runs forever
MrBedfordVan 1:034f79c00c98 103 while(1) {
MrBedfordVan 2:b47f8dbf374c 104 // Set up and read ultrasonic sensor after "sample_time"
MrBedfordVan 0:b88af2ed370b 105 usensor.start();
MrBedfordVan 0:b88af2ed370b 106 wait_ms(sample_time);
MrBedfordVan 2:b47f8dbf374c 107 dist=usensor.get_dist_cm(); // read sesnsor distance measure
MrBedfordVan 3:389e402bd42f 108 //pc.printf("Lap %d Distance %d wait_time %d \n\r", lap_count, dist, wait_time); // Debug - display distance to Serial Interface
MrBedfordVan 3:389e402bd42f 109 if (dist < trigger_distance) { // Spotted something closer than trigger_distance from the sensor
MrBedfordVan 2:b47f8dbf374c 110 if (lap_count == 0) { // First Lap - start lap timer
MrBedfordVan 1:034f79c00c98 111 lap_timer.reset();
MrBedfordVan 1:034f79c00c98 112 lap_timer.start();
MrBedfordVan 3:389e402bd42f 113 //pc.printf("Timing... \r"); // Debug to Serial Interface
MrBedfordVan 2:b47f8dbf374c 114 textLCD("Timing..........", 1); // Message to LCD
MrBedfordVan 1:034f79c00c98 115 } else { // Completed a lap
MrBedfordVan 2:b47f8dbf374c 116 lap_time = lap_timer.read(); // Get time for lap
MrBedfordVan 1:034f79c00c98 117 lap_timer.reset();
MrBedfordVan 3:389e402bd42f 118 DisplayLap(lap_count, dist, lap_time, 1);
MrBedfordVan 0:b88af2ed370b 119 }
MrBedfordVan 2:b47f8dbf374c 120 lap_count++; // Increment lap counter by 1
MrBedfordVan 3:389e402bd42f 121 wait(min_laptime); // Wait for a time before starting to monitor sensor for next lap
MrBedfordVan 3:389e402bd42f 122 } // end of something spotted
MrBedfordVan 3:389e402bd42f 123 else // nothing spotted - output debug
MrBedfordVan 3:389e402bd42f 124 {
MrBedfordVan 3:389e402bd42f 125 DisplayLap(lap_count, dist, lap_time, 0);
MrBedfordVan 3:389e402bd42f 126 }
MrBedfordVan 3:389e402bd42f 127 } // end of main while loop
MrBedfordVan 3:389e402bd42f 128
MrBedfordVan 3:389e402bd42f 129
MrBedfordVan 2:b47f8dbf374c 130 } // end of main program
MrBedfordVan 0:b88af2ed370b 131