Quick test of the Wi-Go Magnetometer
Dependencies: TSI mbed MAG3110
main.cpp
- Committer:
- SomeRandomBloke
- Date:
- 2013-05-17
- Revision:
- 1:d45fc466a46e
- Parent:
- 0:26bfff579f01
- Child:
- 2:c19e63728e2e
File content as of revision 1:d45fc466a46e:
#include "mbed.h" #include "TSISensor.h" #include "math.h" //PwmOut r (LED_RED); //PwmOut g (LED_GREEN); //PwmOut b (LED_BLUE); #define MAG_ADDR 0x1D // (0x0E << 1) //0x1D // define register values #define MAG_DR_STATUS 0x00 #define MAG_OUT_X_MSB 0x01 #define MAG_OUT_X_LSB 0x02 #define MAG_OUT_Y_MSB 0x03 #define MAG_OUT_Y_LSB 0x04 #define MAG_OUT_Z_MSB 0x05 #define MAG_OUT_Z_LSB 0x06 #define MAG_WHO_AM_I 0x07 #define MAG_SYSMOD 0x08 #define MAG_OFF_X_MSB 0x09 #define MAG_OFF_X_LSB 0x0A #define MAG_OFF_Y_MSB 0x0B #define MAG_OFF_Y_LSB 0x0C #define MAG_OFF_Z_MSB 0x0D #define MAG_OFF_Z_LSB 0x0E #define MAG_DIE_TEMP 0x0F #define MAG_CTRL_REG1 0x10 #define MAG_CTRL_REG2 0x11 // what should WHO_AM_I return? #define MAG_3110_WHO_AM_I_VALUE 0xC4 // Fields in registers // CTRL_REG1: dr2,dr1,dr0 os1,os0 fr tm ac // Sampling rate from 80Hz down to 0.625Hz #define MAG_3110_SAMPLE80 0 #define MAG_3110_SAMPLE40 0x20 #define MAG_3110_SAMPLE20 0x40 #define MAG_3110_SAMPLE10 0x60 #define MAG_3110_SAMPLE5 0x80 #define MAG_3110_SAMPLE2_5 0xA0 #define MAG_3110_SAMPLE1_25 0xC0 #define MAG_3110_SAMPLE0_625 0xE0 // How many samples to average (lowers data rate) #define MAG_3110_OVERSAMPLE1 0 #define MAG_3110_OVERSAMPLE2 0x08 #define MAG_3110_OVERSAMPLE3 0x10 #define MAG_3110_OVERSAMPLE4 0x18 // read only 1 byte per axis #define MAG_3110_FASTREAD 0x04 // do one measurement (even if in standby mode) #define MAG_3110_TRIGGER 0x02 // put in active mode #define MAG_3110_ACTIVE 0x01 // CTRL_REG2: AUTO_MRST_EN _ RAW MAG_RST _ _ _ _ _ // reset sensor after each reading #define MAG_3110_AUTO_MRST_EN 0x80 // don't subtract user offsets #define MAG_3110_RAW 0x20 // reset magnetic sensor after too-large field #define MAG_3110_MAG_RST 0x10 // DR_STATUS Register ZYXOW ZOW YOW XOW ZYXDR ZDR YDR XDR #define MAG_3110_ZYXDR 0x08 //0x0E //7-bit address for the MAG3110, doesn't change DigitalOut myled(PTB10); DigitalOut redLed(LED_RED); DigitalOut greenLed(LED_GREEN); DigitalOut blueLed(LED_BLUE); TSISensor tsi; I2C i2c(PTE0, PTE1); int avgX, avgY, newX, tempXmin, tempXmax, newY, tempYmin, tempYmax; struct settings_t { long maxX, minX, maxY, minY; } settings; const int addr = MAG_ADDR; // Read a single byte form 8 bit register, return as int int readReg(char regAddr) { char cmd[1]; cmd[0] = regAddr; i2c.write(addr, cmd, 1); cmd[0] = 0x00; i2c.read(addr, cmd, 1); return (int)( cmd[0]); } // read a register per, pass first reg value, reading 2 bytes increments register // Reads MSB first then LSB int readVal(char regAddr) { char cmd[2]; cmd[0] = regAddr; i2c.write(addr, cmd, 1); cmd[0] = 0x00; cmd[1] = 0x00; i2c.read(addr, cmd, 2); return (int)( (cmd[1]|(cmd[0] << 8))); //concatenate the MSB and LSB } #define PI 3.14159265359 #define ON 0 #define OFF 1 void calXY() //magnetometer calibration: finding max and min of X, Y axis { int tempXmax, tempXmin, tempYmax, tempYmin, newX, newY; redLed = ON; // lcd.setCursor(0,1); // lcd.print(“Rotate the car “); // delay(1000); // lcd.setCursor(0,1); // lcd.print(“and press button”); // delay(1000); // lcd.setCursor(0,1); // lcd.print(“Now, begin! “); // delay(500); // Wait for slider to be pressed at one end > 30mm while( tsi.readDistance() < 30 && tsi.readDistance() != 0 ) { redLed = OFF; wait(0.2); redLed = ON; wait(0.2); } // Wait for release while( tsi.readDistance() != 0 ) { redLed = OFF; wait(0.2); redLed = ON; wait(0.2); } redLed = OFF; wait(1.0); tempXmax = tempXmin = readVal(MAG_OUT_X_MSB); tempYmax = tempYmin = readVal(MAG_OUT_Y_MSB); int changeCount = 10000; bool change = false; while(changeCount) { // digitalRead(10) == LOW) { // for(int x=0; x<100000; x++); { //newX = readx(); //newY = ready(); newX = readVal(MAG_OUT_X_MSB); newY = readVal(MAG_OUT_Y_MSB); if (newX > tempXmax) { tempXmax = newX; change = true; } if (newX < tempXmin) { tempXmin = newX; change = true; } if (newY > tempYmax) { tempYmax = newY; change = true; } if (newY < tempYmin) { tempYmin = newY; change = true; } if( change ) change = false; else changeCount--; // printf("X max %d min %d, Y max %d min %d\n",tempXmax, tempXmin, tempYmax, tempYmin); } settings.maxX = tempXmax; settings.minX = tempXmin; settings.maxY = tempYmax; settings.minY = tempYmin; //X max 65173 min 64850, Y max 490 min 141 //store new X, Y values in the EEPROM // eeprom_write_block((const void*)&settings, (void*)0, sizeof(settings)); avgX=(settings.maxX+settings.minX)/2; avgY=(settings.maxY+settings.minY)/2; redLed = OFF; // Wait for slider to be pressed at one end > 30mm while( tsi.readDistance() < 30 && tsi.readDistance() != 0 ) { greenLed = OFF; wait(0.2); greenLed = ON; wait(0.2); } // Wait for release while( tsi.readDistance() != 0 ) { greenLed = OFF; wait(0.2); greenLed = ON; wait(0.2); } greenLed = OFF; wait(1.0); // lcd.setCursor(0,1); // lcd.print(“Calibration done”); //delay(3000); // lcd.setCursor(0,1); // lcd.print(” “); } int main() { char cmd[2]; // r.period(0.001); // g.period(0.001); // b.period(0.001); printf("MAG3110 Test\n"); redLed = OFF; greenLed = OFF; blueLed = OFF; cmd[0] = MAG_CTRL_REG2; cmd[1] = 0x80; i2c.write(addr, cmd, 2); // wait(0.1); cmd[0] = MAG_CTRL_REG1; cmd[1] = MAG_3110_SAMPLE80+MAG_3110_OVERSAMPLE2+MAG_3110_ACTIVE; // 0x91; i2c.write(addr, cmd, 2); // Get some values printf("DR_STATUS %X\n", readReg( MAG_DR_STATUS )); printf("WHO_AM_I %X\n", readReg( MAG_WHO_AM_I )); printf("SYSMOD %X\n", readReg( MAG_SYSMOD )); printf("DIE_TEMP %d\n", readReg( MAG_DIE_TEMP )); printf("OFF_X %d\n", readVal( MAG_OFF_X_MSB )); printf("OFF_Y %d\n", readVal( MAG_OFF_Y_MSB )); printf("OFF_Z %d\n", readVal( MAG_OFF_Z_MSB )); printf("CTRL_REG1 %X\n", readReg( MAG_CTRL_REG1 )); printf("CTRL_REG2 %X\n", readReg( MAG_CTRL_REG2 )); // r = 1; // g = 0; // b = 0; settings.maxX = 65173; settings.minX = 64850; settings.maxY = 490; settings.minY = 141; //X max 65173 min 64850, Y max 490 min 141 avgX=(settings.maxX+settings.minX)/2; avgY=(settings.maxY+settings.minY)/2; printf("avgX = %d, avgY = %d\n", avgX, avgY); // avgX = 0; // avgY = 0; printf("calibrate\n"); calXY(); printf("....Finished\n"); printf("avgX = %d, avgY = %d\n", avgX, avgY); // greenLed = 1; redLed = OFF; greenLed = OFF; blueLed = OFF; while (1) { wait(0.5); int xVal = readVal(MAG_OUT_X_MSB); int yVal = readVal(MAG_OUT_Y_MSB); float heading = (atan2((double)(yVal-avgY),(double)(xVal-avgX)))*180/PI; // float heading = (atan2((double)(xVal-avgX),(double)(yVal-avgY)))*180/PI; if (abs(heading) <= 22.5) { printf("N\n"); blueLed = ON; } else blueLed = OFF; if (abs(heading) >= 157.5) printf("S\n"); if (heading >= 67.5 && heading <= 112.5) printf("E \n"); if (heading <= -67.5 && heading >= -112.5) printf("W \n"); if (heading > 22.5 && heading < 67.5) printf("NE\n"); if (heading < -22.5 && heading > -67.5) printf("NW\n"); if (heading > 112.5 && heading < 157.5) printf("SE\n"); if (heading < -112.5 && heading > -157.5) printf("SW\n"); if (heading < 0) heading += 360.0; printf("xVal - avgX = %d, yVal - avgY = %d ", xVal-avgX, yVal-avgY); printf("X = %d, Y = %d, Heading %f\n", xVal, yVal, heading); // printf("2 byte: X = %d ", readVal( 0x01 )); // printf(" Y = %d ", readVal( 0x03 )); // printf(" Z = %d\n", readVal( 0x05 )); // printf("1 byte: X = %d ", readx()); // printf(" Y = %d ", ready()); // printf(" Z = %d\n", readz()); } }