File content as of revision 0:553fab92a347:

#include "mbed.h"
#include "motordriver.h"
#include "ultrasonic.h"

DigitalOut  ledFwd(p8);
DigitalOut  ledRev(p9);

Motor A(p26, p16, p25, 1); // pwm, fwd, rev, can brake
Motor B(p21, p22, p23, 1); // pwm, fwd, rev, can brake

Serial pc(USBTX, USBRX);
Serial esp(p28, p27); // tx, rx

PwmOut mySpeaker(p24);

void dist(int);
ultrasonic mu(p6, p7, .5, 2, &dist); //Check every .5 sec, timeout 1 sec,call dist when the distance changes

void dist(int distance)
{
    if(distance < 1000) { // Distance is in the unit of cm
        pc.printf("stop by sonar \r\n");
        A.stop(0.5);
        B.stop(0.5);
        ledFwd = 0;
        mySpeaker = 0.5; // Play Beep sound
    }
}

// some test values to show on web page
AnalogIn DistSensor(p20);
AnalogIn   Ain1(p18);
AnalogIn   Ain2(p19);

float temperature, AdcIn, Ht;
float R1=100000, R2=10000; // resistor values to give a 10:1 reduction of measured AnalogIn voltage
char Vcc[10];
char Temp[10];

// things for sending/receiving data over serial
volatile int tx_in=0;
volatile int tx_out=0;
volatile int rx_in=0;
volatile int rx_out=0;
const int buffer_size = 4095;
char tx_buffer[buffer_size+1];
char rx_buffer[buffer_size+1];
void Tx_interrupt();
void Rx_interrupt();
void send_line();
void read_line();

int DataRX;
int update;
int count;
char cmdbuff[1024];
char replybuff[4096];
char webdata[4096]; // This may need to be bigger depending on WEB browser used
char webbuff[4096];     // Currently using 1986 characters, Increase this if more web page data added
char timebuf[30];
void SendCMD(),getreply(),ReadWebData(),startserver();
void gettime(),setRTC(),gettemp(),getbattery();
char rx_line[1024];
int port        =80;  // set server port
int SERVtimeout =5;    // set server timeout in seconds in case link breaks.
struct tm t;

int main()
{
    pc.baud(9600);
    esp.baud(9600);
    ledFwd = 1;
    // Setup a serial interrupt function to receive data
    esp.attach(&Rx_interrupt, Serial::RxIrq);
    // Setup a serial interrupt function to transmit data
    esp.attach(&Tx_interrupt, Serial::TxIrq);
    startserver();
    wait(0.01);
    mu.startUpdates();   //start measuring the distance in sonar
    DataRX=0;
    count=0;
    mySpeaker.period(1.0/500.0); // 500hz period
    while(1) {
        if(DataRX==1) {
            ReadWebData();
            esp.attach(&Rx_interrupt, Serial::RxIrq);
        }
        float stateA = A.state();
        float stateB = B.state();
        if((stateA > 0 && stateA <= 1)&&(stateB > 0 && stateB <= 1)) { // obstacle within 10 cm and robot is still moving
            mu.checkDistance();
        } else if((stateA < 0 && stateA >= -1)&&(stateB < 0 && stateB >= -1)) { // If moving rev
            float currDist = DistSensor;
            pc.printf("currDist: %f",currDist);
            if(currDist <= 0.5f) {
                A.stop(0.5);
                B.stop(0.5);
                ledRev = 0;
                mySpeaker = 0.5; // Play Beep sound

            }
        }
    }
}

// Reads and processes GET and POST web data
void ReadWebData()
{
    wait_ms(200);
    esp.attach(NULL,Serial::RxIrq);
    DataRX=0;
    memset(webdata, '\0', sizeof(webdata));
    strcpy(webdata, rx_buffer);
    memset(rx_buffer, '\0', sizeof(rx_buffer));
    rx_in = 0;
    rx_out = 0;
    // check web data for form information
    if( strstr(webdata, "check=BotFwd") != NULL ) {
        A.speed(0.75);
        B.speed(0.75);
        ledRev = 0;
        ledFwd = 1;
    }
    if( strstr(webdata, "check=BotRev") != NULL ) {
        A.speed(-0.75);
        B.speed(-0.75);
        ledFwd = 0;
        ledRev = 1;
    }
    if( strstr(webdata, "check=BotStop") != NULL ) {
        A.stop(0.5);
        B.stop(0.5);
        ledFwd = 0;
        ledRev = 0;
    }
    if( strstr(webdata, "check=BotLeft") != NULL ) {
        B.stop(0.5);
        A.speed(0.5);

    }
    if( strstr(webdata, "check=BotRight") != NULL ) {
        A.stop(0.5);
        B.speed(0.5);
    }
    if( strstr(webdata, "POST") != NULL ) { // set update flag if POST request
        update=1;
    }
    if( strstr(webdata, "GET") != NULL && strstr(webdata, "favicon") == NULL ) { // set update flag for GET request but do not want to update for favicon requests
        update=1;
    }
}
// Starts webserver
void startserver()
{
    pc.printf("Resetting ESP Device....\r\n");
    strcpy(cmdbuff,"node.restart()\r\n");
    SendCMD();
    wait(2);
    getreply();

    pc.printf("\nStarting Server.....\r\n> ");
    //create server
    sprintf(cmdbuff, "srv=net.createServer(net.TCP,%d)\r\n",SERVtimeout);
    SendCMD();
    getreply();
    wait(0.5);
    strcpy(cmdbuff,"srv:listen(80,function(conn)\r\n");
    SendCMD();
    getreply();
    wait(0.3);
    strcpy(cmdbuff,"conn:on(\"receive\",function(conn,payload) \r\n");
    SendCMD();
    getreply();
    wait(0.3);

    //print data to mbed
    strcpy(cmdbuff,"print(payload)\r\n");
    SendCMD();
    getreply();
    wait(0.2);

    //web page data
    strcpy(cmdbuff,"conn:send('<!DOCTYPE html><html><body><h1>ESP8266 Mbed IoT Web Controller</h1>')\r\n");
    SendCMD();
    getreply();
    wait(0.4);
    strcpy(cmdbuff,"conn:send('<form method=\"POST\"')\r\n");
    SendCMD();
    getreply();
    wait(0.3);
    strcpy(cmdbuff, "conn:send('<p><input type=\"radio\" name=\"check\" value=\"BotFwd\"> Move Robot Forward')\r\n");
    SendCMD();
    getreply();
    wait(0.3);
    strcpy(cmdbuff, "conn:send('<p><input type=\"radio\" name=\"check\" value=\"BotRev\"> Move Robot Reverse')\r\n");
    SendCMD();
    getreply();
    wait(0.3);
    strcpy(cmdbuff, "conn:send('<p><input type=\"radio\" name=\"check\" value=\"BotStop\"> Stop Robot')\r\n");
    SendCMD();
    getreply();
    wait(0.3);
    strcpy(cmdbuff, "conn:send('<p><input type=\"radio\" name=\"check\" value=\"BotLeft\"> Turn Robot Left')\r\n");
    SendCMD();
    getreply();
    wait(0.3);
    strcpy(cmdbuff, "conn:send('<p><input type=\"radio\" name=\"check\" value=\"BotRight\"> Turn Robot Right')\r\n");
    SendCMD();
    getreply();
    wait(0.3);
    strcpy(cmdbuff,"conn:send('<p><input type=\"submit\" value=\"Send to Robot\"></form>')\r\n");
    SendCMD();
    getreply();
    wait(0.3);
    strcpy(cmdbuff, "conn:send('<p><h2>How to use:</h2><ul><li>Select a radiobutton </li><li>Click Send to Robot button</li></ul></body></html>')\r\n");
    SendCMD();
    getreply();
    wait(0.5);
    // end web page data
    strcpy(cmdbuff, "conn:on(\"sent\",function(conn) conn:close() end)\r\n"); // close current connection
    SendCMD();
    getreply();
    wait(0.3);
    strcpy(cmdbuff, "end)\r\n");
    SendCMD();
    getreply();
    wait(0.2);
    strcpy(cmdbuff, "end)\r\n");
    SendCMD();
    getreply();
    wait(0.2);

    strcpy(cmdbuff, "tmr.alarm(0, 1000, 1, function()\r\n");
    SendCMD();
    getreply();
    wait(0.2);
    strcpy(cmdbuff, "if wifi.sta.getip() == nil then\r\n");
    SendCMD();
    getreply();
    wait(0.2);
    strcpy(cmdbuff, "print(\"Connecting to AP...\\n\")\r\n");
    SendCMD();
    getreply();
    wait(0.2);
    strcpy(cmdbuff, "else\r\n");
    SendCMD();
    getreply();
    wait(0.2);
    strcpy(cmdbuff, "ip, nm, gw=wifi.sta.getip()\r\n");
    SendCMD();
    getreply();
    wait(0.2);
    strcpy(cmdbuff,"print(\"IP Address: \",ip)\r\n");
    SendCMD();
    getreply();
    wait(0.2);
    strcpy(cmdbuff,"tmr.stop(0)\r\n");
    SendCMD();
    getreply();
    wait(0.2);
    strcpy(cmdbuff,"end\r\n");
    SendCMD();
    getreply();
    wait(0.2);
    strcpy(cmdbuff,"end)\r\n");
    SendCMD();
    getreply();
    wait(0.2);
    pc.printf("\n\nReady to go .....\r\n\n");
}


// ESP Command data send
void SendCMD()
{
    int i;
    char temp_char;
    bool empty;
    i = 0;
// Start Critical Section - don't interrupt while changing global buffer variables
    NVIC_DisableIRQ(UART1_IRQn);
    empty = (tx_in == tx_out);
    while ((i==0) || (cmdbuff[i-1] != '\n')) {
// Wait if buffer full
        if (((tx_in + 1) % buffer_size) == tx_out) {
// End Critical Section - need to let interrupt routine empty buffer by sending
            NVIC_EnableIRQ(UART1_IRQn);
            while (((tx_in + 1) % buffer_size) == tx_out) {
            }
// Start Critical Section - don't interrupt while changing global buffer variables
            NVIC_DisableIRQ(UART1_IRQn);
        }
        tx_buffer[tx_in] = cmdbuff[i];
        i++;
        tx_in = (tx_in + 1) % buffer_size;
    }
    if (esp.writeable() && (empty)) {
        temp_char = tx_buffer[tx_out];
        tx_out = (tx_out + 1) % buffer_size;
// Send first character to start tx interrupts, if stopped
        esp.putc(temp_char);
    }
// End Critical Section
    NVIC_EnableIRQ(UART1_IRQn);
    return;
}

// Get Command and ESP status replies
void getreply()
{
    read_line();
    sscanf(rx_line,replybuff);
}

// Read a line from the large rx buffer from rx interrupt routine
void read_line()
{
    int i;
    i = 0;
// Start Critical Section - don't interrupt while changing global buffer variables
    NVIC_DisableIRQ(UART1_IRQn);
// Loop reading rx buffer characters until end of line character
    while ((i==0) || (rx_line[i-1] != '\r')) {
// Wait if buffer empty
        if (rx_in == rx_out) {
// End Critical Section - need to allow rx interrupt to get new characters for buffer
            NVIC_EnableIRQ(UART1_IRQn);
            while (rx_in == rx_out) {
            }
// Start Critical Section - don't interrupt while changing global buffer variables
            NVIC_DisableIRQ(UART1_IRQn);
        }
        rx_line[i] = rx_buffer[rx_out];
        i++;
        rx_out = (rx_out + 1) % buffer_size;
    }
// End Critical Section
    NVIC_EnableIRQ(UART1_IRQn);
    rx_line[i-1] = 0;
    return;
}


// Interupt Routine to read in data from serial port
void Rx_interrupt()
{
    DataRX=1;
// Loop just in case more than one character is in UART's receive FIFO buffer
// Stop if buffer full
    while ((esp.readable()) && (((rx_in + 1) % buffer_size) != rx_out)) {
        rx_buffer[rx_in] = esp.getc();
// Uncomment to Echo to USB serial to watch data flow
        pc.putc(rx_buffer[rx_in]);
        rx_in = (rx_in + 1) % buffer_size;
    }
    return;
}

// Interupt Routine to write out data to serial port
void Tx_interrupt()
{
// Loop to fill more than one character in UART's transmit FIFO buffer
// Stop if buffer empty
    while ((esp.writeable()) && (tx_in != tx_out)) {
        esp.putc(tx_buffer[tx_out]);
        tx_out = (tx_out + 1) % buffer_size;
    }
    return;
}