Lorenzo Paris
The program is part of the assignment of CE713 Internet of Things. It provides a simple solution to activate an Escalator only when it really needs to be done by using a Sonar Sensor.
Dependencies: EthernetNetIf HTTPServer TextLCD mbed
Diff: main.cpp
- Revision:
- 0:e0539419df78
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Sat Jan 13 13:11:20 2018 +0000
@@ -0,0 +1,243 @@
+#include "mbed.h"
+#include "TextLCD.h"
+#include "EthernetNetIf.h"
+#include "HTTPServer.h"
+
+TextLCD lcd(p15, p16, p17, p18, p19, p20); // LCD: RS, E, D4-D7
+SPI spi(p5, p6, p7); // SPI: MOSI, MISO, SCLK (MISO not used with LCD)
+DigitalOut lat(p8); // data latch for LED driver TLC59281
+DigitalOut Sel0(p26); // input select bits:
+DigitalOut Sel1(p25); // "
+DigitalOut Sel2(p24); // "
+DigitalIn In0(p14); // input from switches, keypad etc
+DigitalIn In1(p13); // "
+DigitalIn In2(p12); // "
+DigitalIn In3(p11); // "
+I2C i2c(p9, p10); // I2C: SDA, SCL pins
+DigitalOut Trigger(p28); // Ultrasonic rangefinder trigger pin
+DigitalIn Echo(p27); // Ultrasonic rangefinder echo pin
+Timer Sonar; // Ultrasonic timer
+DigitalOut led1(LED1);
+Serial out(USBTX, USBRX);
+short LEDbits = 0; // global led status used for readback
+
+/*Functions used to initialize the Internet connection*/
+/*LocalFileSystem fs("webfs");
+EthernetNetIf eth;
+HTTPServer svr;
+Ticker WebUpdate; // Interrupt timer to update web page //
+
+extern "C" void mbed_mac_address(char *mac);
+
+void WebServerPoll () {
+ Net::poll();
+ led1=!led1; //Show that we are alive
+}
+
+int InitWebServer() {
+ EthernetErr ethErr = eth.setup();
+ if(ethErr) {
+ return -1;
+ }
+
+ FILE *fp = fopen("/webfs/index.htm", "w"); // Open "out.txt" on the local file system for writing
+ fprintf(fp, "<html><head><title>Hello World online</title></head><body><h1>Hello World from Mbed NXP LPC1768!</h1></body></html>");
+ fclose(fp); // Close file
+ FSHandler::mount("/webfs", "/files"); // Mount /webfs path on /files web path
+ FSHandler::mount("/webfs", "/"); // Mount /webfs path on web root path
+ svr.addHandler<SimpleHandler>("/hello");
+ svr.addHandler<RPCHandler>("/rpc");
+ svr.addHandler<FSHandler>("/files");
+ svr.addHandler<FSHandler>("/"); // Default handler
+ svr.bind(80); // Example : http://155.245.21.144
+ WebUpdate.attach(&WebServerPoll, 0.1); // update webserver every 100ms
+ return 0; // return without error
+}
+
+void HTTPText(char t[4000]) {
+ FILE *fp = fopen("/webfs/index.htm", "w"); // Open "out.txt" on the local file system for writing
+ fprintf(fp, t);
+ fclose(fp);
+}*/
+
+/*Function used to initialize the board sensors and actuators*/
+int ReadSonar() {
+ Trigger = 1; // set sonar trigger pulse high
+ Sonar.reset(); // reset sonar timer
+ wait_us(10.0); // 10 us pulse
+ Trigger = 0; // set sonar trigger pulse low
+ while (Echo == 0) {}; // wait for echo high (8 cycles have been transmitted)
+ Sonar.start(); // echo high so start timer
+ while (Echo == 1) {}; // wait for echo low
+ Sonar.stop(); // echo low so stop timer
+ return (Sonar.read_us()*10)/58; // read timer and scale to mm
+}
+
+void InitLEDs() {
+ lat = 0; // latch must start low
+ spi.format(16,0); // SPI 16 bit data, low state, high going clock
+ spi.frequency(1000000); // 1MHz clock rate
+}
+
+void SetLEDs(short ledall) {
+ LEDbits = ledall; // update global led status
+ spi.write((LEDbits & 0x03ff) | ((LEDbits & 0xa800) >> 1) | ((LEDbits & 0x5400) << 1));
+ lat = 1; // latch pulse start
+ lat = 0; // latch pulse end
+}
+
+void SetLED(short LEDNo, short LEDState) {
+ LEDNo = ((LEDNo - 1) & 0x0007) + 1; // limit led number
+ LEDState = LEDState & 0x0003; // limit led state
+ LEDNo = (8 - LEDNo) * 2; // offset of led state in 'LEDbits'
+ LEDState = LEDState << LEDNo;
+ short statemask = ((0x0003 << LEDNo) ^ 0xffff); // mask used to clear led state
+ LEDbits = ((LEDbits & statemask) | LEDState); // clear and set led state
+ SetLEDs(LEDbits);
+}
+
+void SelInput(short Input) {
+ Sel0 = Input & 0x0001; // set sel[0:2] pins
+ Sel1 = (Input >> 1) & 0x0001; //
+ Sel2 = (Input >> 2) & 0x0001; //
+}
+
+short ReadSwitches() {
+ SelInput(5); // select least significant 4 switches in[3:0]
+ short Switches = In0 + (In1 << 1) + (In2 << 2) + (In3 << 3);
+ SelInput(4); // select most significant 4 switches in[3:0]
+ return (Switches + (In0 << 4) + (In1 << 5) + (In2 << 6) + (In3 << 7));
+}
+
+short ReadSwitch(short SwitchNo) {
+ SwitchNo = ((SwitchNo - 1) & 0x0007) + 1; // limit switch number
+ SwitchNo = 8 - SwitchNo; // offset of switch state in ReadSwitches()
+ short SwitchState = ReadSwitches(); // read switch states
+ SwitchState = SwitchState >> SwitchNo; // shift selected switch state into ls bit
+ return (SwitchState & 0x0001); // mask out and return switch state
+}
+
+/*Set reference distance:
+if the distance sensed by the sonar is the same for 9 seconds,
+it will be the reference distance, otherwise restart the cycle*/
+int setDistance() {
+ int D_temp = ReadSonar();
+ int D;
+
+ lcd.cls();
+ lcd.printf("setting distance");
+
+ SetLEDs(0);
+
+ for(int i=0; i<9; i++) {
+ D = ReadSonar();
+
+ /*Allow an extra range of 10 mm for setting the distance*/
+ if(D_temp - 10 < D && D_temp + 10 > D) {
+ D_temp = D; //reset D_temp
+ i = 0; //restart setting the distance
+ SetLEDs(0);
+ }
+ else {
+ wait(1);
+ SetLED(i%9, 1);
+ }
+ }
+
+ lcd.cls();
+ lcd.printf("distance set at\n%d", D);
+ wait(2);
+
+ return D;
+}
+
+int main() {
+ InitLEDs();
+ //InitWebServer();
+ int D = setDistance();
+ int D1;
+ int T_ON = 0; //Time (seconds) the escalator is ON
+ int T_tot = 0; //Time (seconds) since the system started working
+ int timeSaved; //Time saved (seconds)
+ int energySaved = 0; //Percentage of energy saved
+ char ON = 0;
+
+ //char Buffer[4000];
+
+ while(1) {
+ D1 = ReadSonar();
+
+ /*ESCALATOR_POWER_ON*/
+ if(D1 < D - 10) { //Allow an extra range of 10 mm when sensing the distance
+ T_ON++;
+ ON = 1;
+ }
+
+ /*ESCALATOR_POWER_OFF*/
+ else
+ ON = 0;
+
+ T_tot++;
+ energySaved = 100 - ((100*T_ON)/T_tot); //(previously the escalator was always ON)
+ timeSaved = T_tot - T_ON;
+
+ int firstOnSwitch = 0; //used to identify the switch
+
+ for (int a= 1; a < 9; a++ ) { // map Switch states to led's
+ SetLED (a,(ReadSwitch(a) + 1));
+
+ if(ReadSwitch(a) == 1) {
+ firstOnSwitch = a;
+ }
+ }
+
+ /*Display the data collected on the LCD of the board*/
+ switch(firstOnSwitch)
+ {
+ /*Switch 1: percentage of energy saved*/
+ case 1:
+ lcd.cls();
+ lcd.printf("Energy Saved =\n%d%c", energySaved, '%');
+ break;
+
+ /*Switch 2: total elapsed time since the system started working*/
+ case 2:
+ lcd.cls();
+ lcd.printf("T_tot:\n%d", T_tot);
+ break;
+
+ /*Switch 3: amount of time the escalator has been ON*/
+ case 3:
+ lcd.cls();
+ lcd.printf("T_ON =\n%d", T_ON);
+ break;
+
+ /*Switch 4: amount of time saved (time the escalator has been OFF)*/
+ case 4:
+ lcd.cls();
+ lcd.printf("Time saved =\n%d", timeSaved);
+ break;
+
+ /*No Switch: current state of the escalator (ON/OFF)*/
+ default:
+ if(ON == 1) {
+ lcd.cls();
+ lcd.printf("Escalator\nON");
+ }
+ else {
+ lcd.cls();
+ lcd.printf("Escalator\nOFF");
+ }
+ }
+
+ /*HTML and CSS code to be sent to the dedicated Web Page (MAC Address)*/
+ /*sprintf(Buffer, "<!DOCTYPE html><html><head><title>Escalator Smart Switch</title></head><body><style type=\"text/css\">.tg {border-collapse:collapse;border-spacing:0;border-color:#aabcfe;margin:0px auto;}.tg td{font-family:Arial, sans-serif;font-size:14px;padding:10px 5px;border-style:solid;border-width:1px;overflow:hidden;word-break:normal;border-color:#aabcfe;color:#669;background-color:#e8edff;}.tg th{font-family:Arial, sans-serif;font-size:14px;font-weight:normal;padding:10px 5px;border-style:solid;border-width:1px;overflow:hidden;word-break:normal;border-color:#aabcfe;color:#039;background-color:#b9c9fe;}.tg .tg-wfog{font-weight:bold;font-size:22px;color:#f56b00;text-align:center;vertical-align:top}.tg .tg-3v14{background-color:#D2E4FC;font-weight:bold;font-size:18px;text-align:center;vertical-align:top}.tg .tg-5frq{font-style:italic;text-align:center;vertical-align:top}.tg .tg-xqmu{background-color:#D2E4FC;font-style:italic;text-align:center;vertical-align:top}</style>");
+ sprintf(Buffer + strlen(Buffer), "<table class=\"tg\"><tr><th class=\"tg-wfog\" colspan=\"3\">Escalator MAC ADDRESS</th></tr><tr><td class=\"tg-3v14\">Value</td><td class=\"tg-3v14\">Currently</td><td class=\"tg-3v14\">Previously</td></tr>");
+ sprintf(Buffer + strlen(Buffer), "<tr><td class=\"tg-5frq\">Working Time</td><td class=\"tg-5frq\">%d seconds</td><td class=\"tg-5frq\">%d seconds</td></tr>", T_ON, T_tot);
+ sprintf(Buffer + strlen(Buffer), "<tr><td class=\"tg-xqmu\">Working Time Saved</td><td class=\"tg-xqmu\" colspan=\"2\">%d seconds</td></tr>", timeSaved);
+ sprintf(Buffer + strlen(Buffer), "<tr><td class=\"tg-5frq\">Energy Saved</td><td class=\"tg-5frq\" colspan=\"2\">%f</td></tr></table></body></html>", energySaved);
+ HTTPText(Buffer);*/ // write to index.htm
+
+ wait(1);
+ }
+}