BMA180 adr. 0x41 from BlazeX
BMA180.cpp@0:6904212fb1d1, 2012-05-30 (annotated)
- Committer:
- caroe
- Date:
- Wed May 30 10:43:42 2012 +0000
- Revision:
- 0:6904212fb1d1
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
caroe | 0:6904212fb1d1 | 1 | #include "mbed.h" |
caroe | 0:6904212fb1d1 | 2 | #include "BMA180.h" |
caroe | 0:6904212fb1d1 | 3 | |
caroe | 0:6904212fb1d1 | 4 | #define I2CADR_W(ADR) (ADR<<1&0xFE) |
caroe | 0:6904212fb1d1 | 5 | #define I2CADR_R(ADR) (ADR<<1|0x01) |
caroe | 0:6904212fb1d1 | 6 | |
caroe | 0:6904212fb1d1 | 7 | //Initialisieren |
caroe | 0:6904212fb1d1 | 8 | BMA180::BMA180(I2C & I2CBus_, Timer & GlobalTime_) |
caroe | 0:6904212fb1d1 | 9 | : I2CBus(I2CBus_), |
caroe | 0:6904212fb1d1 | 10 | GlobalTime(GlobalTime_) |
caroe | 0:6904212fb1d1 | 11 | {} |
caroe | 0:6904212fb1d1 | 12 | |
caroe | 0:6904212fb1d1 | 13 | void BMA180::Init() |
caroe | 0:6904212fb1d1 | 14 | { |
caroe | 0:6904212fb1d1 | 15 | //Nullsetzen |
caroe | 0:6904212fb1d1 | 16 | for(int i= 0; i < 3; i++) |
caroe | 0:6904212fb1d1 | 17 | { |
caroe | 0:6904212fb1d1 | 18 | Offset[i]= 0.0; |
caroe | 0:6904212fb1d1 | 19 | RawAcc[i]= 0; |
caroe | 0:6904212fb1d1 | 20 | Acc[i]= 0; |
caroe | 0:6904212fb1d1 | 21 | } |
caroe | 0:6904212fb1d1 | 22 | |
caroe | 0:6904212fb1d1 | 23 | |
caroe | 0:6904212fb1d1 | 24 | //BMA180 initialisieren |
caroe | 0:6904212fb1d1 | 25 | char tx[2]; |
caroe | 0:6904212fb1d1 | 26 | char rx[1]; |
caroe | 0:6904212fb1d1 | 27 | |
caroe | 0:6904212fb1d1 | 28 | //Schreiben aktivieren |
caroe | 0:6904212fb1d1 | 29 | tx[0]= 0x0D; |
caroe | 0:6904212fb1d1 | 30 | I2CBus.write(I2CADR_W(BMA180_ADRESS), tx, 1); |
caroe | 0:6904212fb1d1 | 31 | I2CBus.read (I2CADR_R(BMA180_ADRESS), rx, 1); |
caroe | 0:6904212fb1d1 | 32 | tx[1]= rx[0] & 0xEF | (0x01<<4); |
caroe | 0:6904212fb1d1 | 33 | I2CBus.write(I2CADR_W(BMA180_ADRESS), tx, 2); |
caroe | 0:6904212fb1d1 | 34 | |
caroe | 0:6904212fb1d1 | 35 | //Mode: Low-Noise |
caroe | 0:6904212fb1d1 | 36 | tx[0]= 0x30; |
caroe | 0:6904212fb1d1 | 37 | I2CBus.write(I2CADR_W(BMA180_ADRESS), tx, 1); |
caroe | 0:6904212fb1d1 | 38 | I2CBus.read (I2CADR_R(BMA180_ADRESS), rx, 1); |
caroe | 0:6904212fb1d1 | 39 | tx[1]= rx[0] & 0xFC | (0x00<<0); |
caroe | 0:6904212fb1d1 | 40 | I2CBus.write(I2CADR_W(BMA180_ADRESS), tx, 2); |
caroe | 0:6904212fb1d1 | 41 | |
caroe | 0:6904212fb1d1 | 42 | //Range: +-3g |
caroe | 0:6904212fb1d1 | 43 | tx[0]= 0x35; |
caroe | 0:6904212fb1d1 | 44 | I2CBus.write(I2CADR_W(BMA180_ADRESS), tx, 1); |
caroe | 0:6904212fb1d1 | 45 | I2CBus.read (I2CADR_R(BMA180_ADRESS), rx, 1); |
caroe | 0:6904212fb1d1 | 46 | tx[1]= rx[0] & 0xF1 | (0x03<<1); |
caroe | 0:6904212fb1d1 | 47 | I2CBus.write(I2CADR_W(BMA180_ADRESS), tx, 2); |
caroe | 0:6904212fb1d1 | 48 | |
caroe | 0:6904212fb1d1 | 49 | //Bandbreitenfilter: 10Hz |
caroe | 0:6904212fb1d1 | 50 | tx[0]= 0x20; |
caroe | 0:6904212fb1d1 | 51 | I2CBus.write(I2CADR_W(BMA180_ADRESS), tx, 1); |
caroe | 0:6904212fb1d1 | 52 | I2CBus.read (I2CADR_R(BMA180_ADRESS), rx, 1); |
caroe | 0:6904212fb1d1 | 53 | tx[1]= rx[0] & 0x0F | (0x00<<4); |
caroe | 0:6904212fb1d1 | 54 | I2CBus.write(I2CADR_W(BMA180_ADRESS), tx, 2); |
caroe | 0:6904212fb1d1 | 55 | |
caroe | 0:6904212fb1d1 | 56 | Update(); |
caroe | 0:6904212fb1d1 | 57 | } |
caroe | 0:6904212fb1d1 | 58 | |
caroe | 0:6904212fb1d1 | 59 | |
caroe | 0:6904212fb1d1 | 60 | //Rohdaten lesen |
caroe | 0:6904212fb1d1 | 61 | void BMA180::ReadRawData() |
caroe | 0:6904212fb1d1 | 62 | { |
caroe | 0:6904212fb1d1 | 63 | //Beschleunigung für alle 3 Achsen auslesen |
caroe | 0:6904212fb1d1 | 64 | char tx[1]; |
caroe | 0:6904212fb1d1 | 65 | char rx[6]; |
caroe | 0:6904212fb1d1 | 66 | |
caroe | 0:6904212fb1d1 | 67 | tx[0]= 0x02; |
caroe | 0:6904212fb1d1 | 68 | I2CBus.write(I2CADR_W(BMA180_ADRESS), tx, 1); |
caroe | 0:6904212fb1d1 | 69 | I2CBus.read (I2CADR_R(BMA180_ADRESS), rx, 6); |
caroe | 0:6904212fb1d1 | 70 | |
caroe | 0:6904212fb1d1 | 71 | //Aus den einzelnen Bytes den 16-Bit-Wert zusammenbauen |
caroe | 0:6904212fb1d1 | 72 | //Die 2 Statusbits muessen "abgeschnitten" werden |
caroe | 0:6904212fb1d1 | 73 | RawAcc[0]= (rx[1]<<8|rx[0]) & 0xFFFC; |
caroe | 0:6904212fb1d1 | 74 | RawAcc[1]= (rx[3]<<8|rx[2]) & 0xFFFC; |
caroe | 0:6904212fb1d1 | 75 | RawAcc[2]= (rx[5]<<8|rx[4]) & 0xFFFC; |
caroe | 0:6904212fb1d1 | 76 | RawAcc[0]/= 4; |
caroe | 0:6904212fb1d1 | 77 | RawAcc[1]/= 4; |
caroe | 0:6904212fb1d1 | 78 | RawAcc[2]/= 4; |
caroe | 0:6904212fb1d1 | 79 | } |
caroe | 0:6904212fb1d1 | 80 | |
caroe | 0:6904212fb1d1 | 81 | //Update-Methode |
caroe | 0:6904212fb1d1 | 82 | void BMA180::Update() |
caroe | 0:6904212fb1d1 | 83 | { |
caroe | 0:6904212fb1d1 | 84 | //Beschleunigung für alle 3 Achsen auslesen |
caroe | 0:6904212fb1d1 | 85 | ReadRawData(); |
caroe | 0:6904212fb1d1 | 86 | |
caroe | 0:6904212fb1d1 | 87 | //Umrechnungen |
caroe | 0:6904212fb1d1 | 88 | Acc[0]= fConvMPSS * ((float)(RawAcc[0]) + Offset[0]); |
caroe | 0:6904212fb1d1 | 89 | Acc[1]= fConvMPSS * ((float)(RawAcc[1]) + Offset[1]); |
caroe | 0:6904212fb1d1 | 90 | Acc[2]= fConvMPSS * ((float)(RawAcc[2]) + Offset[2]); |
caroe | 0:6904212fb1d1 | 91 | } |
caroe | 0:6904212fb1d1 | 92 | |
caroe | 0:6904212fb1d1 | 93 | //Kalibrieren |
caroe | 0:6904212fb1d1 | 94 | void BMA180::Calibrate(int ms, const short * pRaw1g) |
caroe | 0:6904212fb1d1 | 95 | { |
caroe | 0:6904212fb1d1 | 96 | float AvgCalibAcc[3]= {0.0, 0.0, 0.0}; |
caroe | 0:6904212fb1d1 | 97 | float AvgCalibSampels= 0.0; |
caroe | 0:6904212fb1d1 | 98 | |
caroe | 0:6904212fb1d1 | 99 | //Ende der Kalibrierung in ms Millisekunden berechnen |
caroe | 0:6904212fb1d1 | 100 | int CalibEnd= GlobalTime.read_ms() + ms; |
caroe | 0:6904212fb1d1 | 101 | |
caroe | 0:6904212fb1d1 | 102 | while(GlobalTime.read_ms() < CalibEnd) |
caroe | 0:6904212fb1d1 | 103 | { |
caroe | 0:6904212fb1d1 | 104 | //Rohdaten lesen |
caroe | 0:6904212fb1d1 | 105 | ReadRawData(); |
caroe | 0:6904212fb1d1 | 106 | |
caroe | 0:6904212fb1d1 | 107 | //Durchschnitt bilden |
caroe | 0:6904212fb1d1 | 108 | AvgCalibAcc[0]+= (float)RawAcc[0]; |
caroe | 0:6904212fb1d1 | 109 | AvgCalibAcc[1]+= (float)RawAcc[1]; |
caroe | 0:6904212fb1d1 | 110 | AvgCalibAcc[2]+= (float)RawAcc[2]; |
caroe | 0:6904212fb1d1 | 111 | AvgCalibSampels+= 1.0; |
caroe | 0:6904212fb1d1 | 112 | |
caroe | 0:6904212fb1d1 | 113 | wait_ms(2); |
caroe | 0:6904212fb1d1 | 114 | } |
caroe | 0:6904212fb1d1 | 115 | |
caroe | 0:6904212fb1d1 | 116 | //Genug Daten gesammelt, jetzt den Durchschnitt bilden |
caroe | 0:6904212fb1d1 | 117 | Offset[0]= -((float)(pRaw1g[0]) + AvgCalibAcc[0] / AvgCalibSampels); |
caroe | 0:6904212fb1d1 | 118 | Offset[1]= -((float)(pRaw1g[1]) + AvgCalibAcc[1] / AvgCalibSampels); |
caroe | 0:6904212fb1d1 | 119 | Offset[2]= -((float)(pRaw1g[2]) + AvgCalibAcc[2] / AvgCalibSampels); |
caroe | 0:6904212fb1d1 | 120 | } |