malcolm lear
/
CE713-V01
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main.cpp
00001 // Device Drivers for Labmbed Board 00002 00003 #include "mbed.h" 00004 #include "TextLCD.h" 00005 00006 TextLCD lcd(p15, p16, p17, p18, p19, p20); // LCD: RS, E, D4-D7 00007 SPI spi(p5, p6, p7); // SPI: MOSI, MISO, SCLK (MISO not used with LCD) 00008 DigitalOut lat(p8); // data latch for LED driver TLC59281 00009 DigitalOut Sel0(p26); // input select bits: 00010 DigitalOut Sel1(p25); // " 00011 DigitalOut Sel2(p24); // " 00012 DigitalIn In0(p14); // input from switches, keypad etc 00013 DigitalIn In1(p13); // " 00014 DigitalIn In2(p12); // " 00015 DigitalIn In3(p11); // " 00016 I2C i2c(p9, p10); // I2C: SDA, SCL pins 00017 PwmOut servo1(p21); // Servo 1 PWM pin 00018 PwmOut servo2(p22); // Servo 2 PWM pin 00019 DigitalOut Trigger(p28); // Ultrasonic rangefinder trigger pin 00020 DigitalIn Echo(p27); // Ultrasonic rangefinder echo pin 00021 Timer Sonar; // Ultrasonic timer 00022 00023 // global variables 00024 short LEDbits = 0; // global led status used for readback 00025 const int TMP102Addr = 0x92; // TMP102 temperature I2C address 00026 const int MPU6050Addr = 0xd0; // MPU-6050 accelerometer and Gyro I2C address 00027 float Acceleration[3]; // MPU-6050 x,y,z acceleration values in 1G floating point 00028 float GyroRate[3]; // MPU-6050 x,y,z gyrorates in degrees per second 00029 float GyroOffset[3]; // MPU-6050 x,y,z gyrorates compensation 00030 char AReg[] = { 0x3b, 0x3d, 0x3f }; // MPU-6050 I2C x,y,z accelerometer data registers 00031 char GReg[] = { 0x43, 0x45, 0x47 }; // MPU-6050 I2C x,y,z gyro data registers 00032 00033 void Servo1(float s) { // range +-1 00034 s=s+1; 00035 if (s>=0 && s<=2) { 00036 servo1.pulsewidth(s/2000+0.001); 00037 } 00038 } 00039 00040 void Servo2(float s) { // range +-1 00041 s=s+1; 00042 if (s>=0 && s<=2) { 00043 servo2.pulsewidth(s/2000+0.001); 00044 } 00045 } 00046 00047 void InitServos() { 00048 servo1.period(0.02); 00049 servo2.period(0.02); 00050 Servo1(0); // initiate servo 1 to centre position 00051 Servo2(0); // initiate servo 1 to centre position 00052 } 00053 00054 int ReadSonar() { 00055 Trigger = 1; // set sonar trigger pulse high 00056 Sonar.reset(); // reset sonar timer 00057 wait_us(10.0); // 10 us pulse 00058 Trigger = 0; // set sonar trigger pulse low 00059 while (Echo == 0) {}; // wait for echo high (8 cycles have been transmitted) 00060 Sonar.start(); // echo high so start timer 00061 while (Echo == 1) {}; // wait for echo low 00062 Sonar.stop(); // echo low so stop timer 00063 return (Sonar.read_us()*10)/58; // read timer and scale to mm 00064 } 00065 00066 void InitLEDs() { 00067 lat = 0; // latch must start low 00068 spi.format(16,0); // SPI 16 bit data, low state, high going clock 00069 spi.frequency(1000000); // 1MHz clock rate 00070 } 00071 00072 void SetLEDs(short ledall) { 00073 LEDbits = ledall; // update global led status 00074 spi.write((LEDbits & 0x03ff) | ((LEDbits & 0xa800) >> 1) | ((LEDbits & 0x5400) << 1)); 00075 lat = 1; // latch pulse start 00076 lat = 0; // latch pulse end 00077 } 00078 00079 void SetLED(short LEDNo, short LEDState) { 00080 LEDNo = ((LEDNo - 1) & 0x0007) + 1; // limit led number 00081 LEDState = LEDState & 0x0003; // limit led state 00082 LEDNo = (8 - LEDNo) * 2; // offset of led state in 'LEDbits' 00083 LEDState = LEDState << LEDNo; 00084 short statemask = ((0x0003 << LEDNo) ^ 0xffff); // mask used to clear led state 00085 LEDbits = ((LEDbits & statemask) | LEDState); // clear and set led state 00086 SetLEDs(LEDbits); 00087 } 00088 00089 short ReadLED(short LEDNo) { 00090 LEDNo = ((LEDNo - 1) & 0x0007) + 1; // limit led number 00091 LEDNo = (8 - LEDNo) * 2; // offset of led state in 'LEDbits' 00092 short LEDState = (LEDbits >> LEDNo) & 0x0003; // shift selected led state into ls 2 bits 00093 return LEDState; // return led state 00094 } 00095 00096 short ReadLEDs() { 00097 return LEDbits; // return led status 00098 } 00099 00100 void SelInput(short Input) { 00101 Sel0 = Input & 0x0001; // set sel[0:2] pins 00102 Sel1 = (Input >> 1) & 0x0001; // 00103 Sel2 = (Input >> 2) & 0x0001; // 00104 } 00105 00106 short ReadSwitches() { 00107 SelInput(5); // select least significant 4 switches in[3:0] 00108 short Switches = In0 + (In1 << 1) + (In2 << 2) + (In3 << 3); 00109 SelInput(4); // select most significant 4 switches in[3:0] 00110 return (Switches + (In0 << 4) + (In1 << 5) + (In2 << 6) + (In3 << 7)); 00111 } 00112 00113 short ReadSwitch(short SwitchNo) { 00114 SwitchNo = ((SwitchNo - 1) & 0x0007) + 1; // limit switch number 00115 SwitchNo = 8 - SwitchNo; // offset of switch state in ReadSwitches() 00116 short SwitchState = ReadSwitches(); // read switch states 00117 SwitchState = SwitchState >> SwitchNo; // shift selected switch state into ls bit 00118 return (SwitchState & 0x0001); // mask out and return switch state 00119 } 00120 00121 short ReadKeys() { 00122 SelInput(0); // select Keypad top row 00123 short Keys = (In0 << 15) + (In1 << 14) + (In2 << 13) + (In3 << 12); 00124 SelInput(1); // select Keypad second row 00125 Keys += (In0 << 3) + (In1 << 6) + (In2 << 9) + (In3 << 11); 00126 SelInput(2); // select Keypad third row 00127 Keys += (In0 << 2) + (In1 << 5) + (In2 << 8) + In3; 00128 SelInput(3); // select Keypad forth row 00129 Keys += (In0 << 1) + (In1 << 4) + (In2 << 7) + (In3 << 10); 00130 return (Keys ^ 0xffff); // return inverted (Key press active high) 00131 } 00132 00133 short ReadKey(short KeyNo) { 00134 KeyNo = KeyNo & 0x000f; // limit key number 0 to 15 (0 to F) 00135 short KeyState = ReadKeys(); // read key states 00136 KeyState = KeyState >> KeyNo; // shift selected key state into ls bit 00137 return (KeyState & 0x0001); // mask out and return key state 00138 } 00139 00140 int FindKeyNo() { 00141 short KeyNo; 00142 short KeyPressed = -1; // set KeyPressed to -1 (no key pressed) 00143 short KeyState = ReadKeys(); // read key states 00144 for (KeyNo= 0; KeyNo < 16; KeyNo++ ) { // check all 16 Keys 00145 if (KeyState & 0x0001) { // check key state 00146 if (KeyPressed == -1) { // check if key already found 00147 KeyPressed = KeyNo; // update KeyPressed 00148 } 00149 else { 00150 return -1; // 2 or more keys pressed 00151 } 00152 } 00153 KeyState = KeyState >> 1; // shift to check next key 00154 } 00155 return KeyPressed; // return KeyPressed 00156 } 00157 00158 char FindKeyChar() { 00159 short KeyNo; 00160 char KeyChar = ' '; // set KeyChar to ' ' (no key pressed) 00161 KeyNo = FindKeyNo(); // find key pressed 00162 if (KeyNo < 10 && KeyNo >= 0) { 00163 KeyChar = (char) KeyNo + 0x30; // convert char 0-9 to ascii string '0'-'9' 00164 } 00165 if (KeyNo > 9 && KeyNo < 16) { 00166 KeyChar = (char) KeyNo + 0x37; // convert char 10-15 to ascii string 'A'-'F' 00167 } 00168 return KeyChar; // return key pressed 00169 } 00170 00171 float ReadTemp() { 00172 char Cmd[3]; 00173 Cmd[0] = 0x01; // pointer register value 00174 Cmd[1] = 0x60; // byte 1 of the configuration register 00175 Cmd[2] = 0xa0; // byte 2 of the configuration register 00176 i2c.write(TMP102Addr, Cmd, 3); // select configuration register and write 0x60a0 to it 00177 wait(0.5); // ensure conversion time 00178 Cmd[0] = 0x00; // pointer register value 00179 i2c.write(TMP102Addr, Cmd, 1); // select temperature register 00180 i2c.read(TMP102Addr, Cmd, 2); // read 16-bit temperature register 00181 return (float((Cmd[0] << 8) | Cmd[1]) / 256); // divide by 256 and return temperature 00182 } 00183 00184 signed short ReadMPU6050(int RegAddr) { 00185 char Cmd[3]; 00186 Cmd[0] = RegAddr; // register address 00187 i2c.write(MPU6050Addr, Cmd, 1); // select register to read 00188 i2c.read(MPU6050Addr, Cmd, 2); // read 2 bytes from register 00189 return ((Cmd[0] << 8) | Cmd[1]); // return signed 16 bit value 00190 } 00191 00192 void CalibrateGyros() { 00193 short a,b; 00194 for(a=0; a<3; a++) { 00195 GyroOffset[a] = 0; // clear gyro calibration offsets 00196 for(b=0; b<1000; b++) { 00197 GyroOffset[a] = GyroOffset[a] + (float)ReadMPU6050(GReg[a]); 00198 wait_ms(1); // wait for next sample 00199 } 00200 GyroOffset[a] = GyroOffset[a]/1000; // find average over 1000 samples 00201 } 00202 } 00203 00204 void InitMotion() { 00205 char Cmd[3]; 00206 Cmd[0] = 0xa1; // config register address 00207 Cmd[1] = 0x06; // accelerometer and gyro bandwidth = 5Hz 00208 i2c.write(MPU6050Addr, Cmd, 2); // write data to config register 00209 Cmd[0] = 0x6b; // power management register address 00210 Cmd[1] = 0x00; // data 00211 i2c.write(MPU6050Addr, Cmd, 2); // write data to power management register 00212 Cmd[0] = 0x1b; // gyro configuration register address 00213 Cmd[1] = 0x08; // no gyro self test, +-500 full scale 00214 i2c.write(MPU6050Addr, Cmd, 2); // write data to gyro configuration register 00215 Cmd[0] = 0x19; // sample rate register address 00216 Cmd[1] = 0x07; // sample rate = gyro output rate / 8 00217 i2c.write(MPU6050Addr, Cmd, 2); // write data to sample rate register 00218 CalibrateGyros(); 00219 } 00220 00221 void ReadMotion() { 00222 short a; // Acceleration is in G where 1G = 9.81 ms/s 00223 for(a=0; a<3; a++) { // GyroRate is in degrees per second 00224 Acceleration[a] = (float)ReadMPU6050(AReg[a]) / 16384; 00225 GyroRate[a] = ((float)ReadMPU6050(GReg[a]) - GyroOffset[a]) / 66.5; 00226 } 00227 } 00228 00229 int main() { 00230 00231 float spos = 0; // Test servo position 00232 InitLEDs(); 00233 InitMotion(); 00234 InitServos(); 00235 00236 while(1) { 00237 int a,b; 00238 for (b = 0; b < 4; b++ ) { // select all 4 led states 00239 for (a = 1; a < 9; a++ ) { // set all 8 leds to selected state 00240 SetLED (a,b); // set led 'a' to state 'b' 00241 wait(.05); // wait 0.05 second 00242 } 00243 } 00244 for (a= 1; a < 9; a++ ) { // map Switch states to led's 00245 SetLED (a,(ReadSwitch(a) + 1)); // 00246 wait(.05); // wait 0.05 second 00247 } 00248 float temp = ReadTemp(); // get temperature 00249 lcd.cls(); // clear lcd 00250 lcd.printf("Temp = %f\n", temp); // print temperature 00251 wait(1); // wait 1 second 00252 lcd.cls(); // clear lcd 00253 int swch = ReadSwitches(); // look at Switch states 00254 lcd.printf("Switches = %d\n", swch); // print result 00255 char Key = FindKeyChar(); // look for Key pressed 00256 lcd.printf("Key = %c\n", Key); // print result 00257 wait(1); // wait 1 second 00258 lcd.cls(); // clear lcd 00259 int dist = ReadSonar(); // get distance 00260 lcd.printf("Distance = %d\n", dist); // print result 00261 lcd.printf("Servo = %f\n", spos); // print servo pos 00262 wait(1); // wait 1 second 00263 ReadMotion(); // read new data in from the MPU-6050 00264 lcd.cls(); // clear lcd 00265 lcd.locate(0,0); // print at start of first line 00266 lcd.printf("x%.1f y%.1f z%.1f", Acceleration[0], Acceleration[1], Acceleration[2]); 00267 lcd.locate(0,1); // print at start of second line 00268 lcd.printf("x%.1f y%.1f z%.1f", GyroRate[0], GyroRate[1], GyroRate[2]); 00269 wait(.4); // wait 0.4 second 00270 if (spos < 1) { // is servo at upper limit of 1 00271 spos += .1; // increment servo position 00272 } // 00273 else { // was at upper limit so 00274 spos = -1; // reset servo position 00275 } // 00276 Servo1(spos); // update servo 00277 } 00278 }
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