Diff: main.cpp

Revision:

0:3cbe4eec57ae

Child:

1:6e34363efa95

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed Mar 30 09:46:55 2011 +0000
@@ -0,0 +1,195 @@
+#include "mbed.h"
+
+DigitalOut motor1A(p9);
+DigitalOut motor1B(p10);
+DigitalOut motor2A(p11);
+DigitalOut motor2B(p12);
+DigitalOut motor3A(p13);
+DigitalOut motor3B(p14);
+DigitalOut motor4A(p15);
+DigitalOut motor4B(p16);
+
+DigitalOut digital1(p17);
+DigitalOut digital2(p18);
+DigitalOut digital3(p19);
+DigitalOut digital4(p20);
+
+SPI spi(p5, p6, p7); // mosi(out), miso(in), sclk(clock)
+DigitalOut cs(p8); // cs(select)
+
+PwmOut motor1(p21);
+PwmOut motor2(p22);
+PwmOut motor3(p23);
+PwmOut motor4(p24);
+
+DigitalOut led(LED4);
+
+Serial pc(USBTX, USBRX);
+
+uint8_t* values;
+uint8_t* location;
+
+char buffer[3];
+int i, inValue, bufferIndex;
+
+// maps the value x to a new given range
+double map( double x, double in_min, double in_max, double out_min, double out_max ) {
+    return ( x - in_min ) * ( out_max - out_min ) / ( in_max - in_min ) + out_min;
+}
+
+// shifts 2 8 bit integers into one integer
+int getIntValue( uint8_t high, uint8_t low ) {
+    return ( high << 8 ) | low;
+}
+
+// sets the given pwm value
+void setPWM( int value, PwmOut pwm, DigitalOut a, DigitalOut b ) {
+    // block the motors
+    if ( value > 511 ) {
+        a = 0;
+        b = 0;
+        pwm = 1;
+    } else {
+        // clockwise run
+        if ( value > 255 ) {
+            value = value - 256;
+            a = 0;
+            b = 1;
+        } else {
+            a = 1;
+            b = 0;
+        }
+        // map the 0-255 value to 0-1
+        pwm = map( value, 0, 255, 0, 1 );
+    }
+}
+
+// specifies the action for the user input
+void specifyAction( char action, int value ) {
+    // specify the action
+    switch ( action ) {
+        case 44:
+            // print the analogs and digitals
+            values = location;
+            for ( int i=0; i<16; i++ ) {
+                pc.putc( *( values++ ) );
+            }
+            
+            pc.putc( '\0' );
+            pc.putc( 13 );
+            break;
+        case 162:
+            // set the first PWMs value
+            setPWM( value, motor1, motor1A, motor1B );
+            break;
+        case 163:
+            // set the second PWMs value
+            setPWM( value, motor2, motor2A, motor2B );
+            break;
+        case 164:
+            // set the third PWMs value
+            setPWM( value, motor3, motor3A, motor3B );
+            break;
+        case 165:
+            // set the fourth PWMs value
+            setPWM( value, motor4, motor4A, motor4B );
+            break;
+        case 230:
+            // Goto _reset ?
+            break;
+        case 231:
+            // enable or disable servos
+            if ( value == 1 ) {
+                // enable servo ?
+            } else if ( value == 2 ) {
+                // disable servo ?
+            }
+            break;
+        case 233:
+            // set digitals values
+            digital1 = ( value & 1 );
+            digital2 = ( ( value >> 1 ) & 1 );
+            digital3 = ( ( value >> 2 ) & 1 );
+            digital4 = ( ( value >> 3 ) & 1 );
+            break;
+        default:
+            //pc.printf( "default\n" );
+    }
+}
+
+int readADC( int channel, DigitalOut select ) {
+    // select the device
+    select = 0;
+    
+    // sending the 5 bits + 2 bits to ignore the null bits
+    // coming from the device, so the data that is sent is 11000101
+    uint8_t commandbits = 0xC0;
+    commandbits |= ( channel << 2 );
+    spi.write( commandbits );
+
+    // now the device sends back the readings 12 bits, 7 bits at a time
+    uint8_t high = spi.write(0x0);
+    uint8_t low = spi.write(0x0);
+    low = low >> 2;
+
+    // shift to get the high and low byte
+    high = ( high >> 3 );
+    low = ( high << 5 ) | low;
+
+    // deselect the device
+    select = 1;
+
+    // save the values
+    *(values++) = high;
+    *(values++) = low;
+    
+    return 0;
+}
+
+void serialEvent() {
+    char c = pc.getc();
+    // if we received enter
+    if( c == 13 ) {
+        //pc.printf( "char=[%c] value=[%u]", buffer[0],getIntValue(buffer[1],buffer[2]) );
+        specifyAction( buffer[ 0 ], getIntValue( buffer[ 1 ], buffer[ 2 ] ) );
+        buffer[ 0 ] = '\0';
+        bufferIndex = 0;
+    }
+    else {
+        buffer[ bufferIndex++ ] = c;
+    }
+}
+
+// the main method
+int main() {
+    // Setup the spi for 7 bit data, high steady state clock,
+    // second edge capture, with a 1MHz clock rate
+    spi.format(7,0);
+    spi.frequency(1000000);
+    
+    // specify the usb baud rate, supported are :
+    // 110, 300, 600, 1200, 2400, 4800, 9600, 14400, 19200, 38400, 57600, 115200, 230400, 460800, 921600
+    pc.baud( 921600 );
+
+    // allocate 16 bytes of space for the adc values
+    values = (uint8_t*) malloc(16);
+    // remember the first values aadress
+    location = values;
+
+    // attach a serial interrupt
+    pc.attach( &serialEvent );
+
+    // to indicate programm is running
+    led = 1;
+
+    // endless loop
+    while ( true ) {
+        // start from the beginning
+        values = location;
+        // read the ADC values
+        for ( i = 0; i < 8; i++ ) {
+            readADC( i, cs );
+        }
+    }
+}
+