Ted Parrott / BMA180_2

NA

Dependencies:   BMA180

Fork of BMA180 by John Ermitanio

BMA180.cpp@1:c525baa503a0, 2017-11-16 (annotated)

Committer:
tedparrott6
Date:
Thu Nov 16 14:59:22 2017 +0000
Revision:
1:c525baa503a0
Parent:
0:ff755cb08068 
NA

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jsermita 0:ff755cb08068 1 #include "mbed.h"
jsermita 0:ff755cb08068 2 #include "BMA180.h"
jsermita 0:ff755cb08068 3
tedparrott6 1:c525baa503a0 4 //Serial pc(USBTX, USBRX); // tx, rx
jsermita 0:ff755cb08068 5
jsermita 0:ff755cb08068 6 BMA180::BMA180(PinName sdi, PinName sdo, PinName sck, PinName csb, PinName interrupt) : _csb(csb), _interrupt(interrupt), spi(sdi, sdo, sck){
jsermita 0:ff755cb08068 7 // mosi, miso, sclk
jsermita 0:ff755cb08068 8 _csb = 1;
jsermita 0:ff755cb08068 9 _interrupt = 0;
jsermita 0:ff755cb08068 10 }
jsermita 0:ff755cb08068 11
jsermita 0:ff755cb08068 12 int BMA180::validate(char id, char ver) {
jsermita 0:ff755cb08068 13 char readID;
jsermita 0:ff755cb08068 14 int value = 0;
jsermita 0:ff755cb08068 15
jsermita 0:ff755cb08068 16 readID = readReg(id);
jsermita 0:ff755cb08068 17
jsermita 0:ff755cb08068 18 if(readID == 3) {
jsermita 0:ff755cb08068 19 value = 1;
jsermita 0:ff755cb08068 20 } else {
tedparrott6 1:c525baa503a0 21 //pc.printf("Lost Connection");
jsermita 0:ff755cb08068 22 value = -1;
jsermita 0:ff755cb08068 23 }
jsermita 0:ff755cb08068 24 return value;
jsermita 0:ff755cb08068 25 }
jsermita 0:ff755cb08068 26
jsermita 0:ff755cb08068 27 void BMA180::initBMA180(void) {
jsermita 0:ff755cb08068 28 char readVersion, readID;
jsermita 0:ff755cb08068 29 char byte;
jsermita 0:ff755cb08068 30
jsermita 0:ff755cb08068 31 readID = readReg(CHIPID);
jsermita 0:ff755cb08068 32 readVersion = readReg(VERSION);
jsermita 0:ff755cb08068 33
jsermita 0:ff755cb08068 34 if(readID == 3) {
tedparrott6 1:c525baa503a0 35 //pc.printf("Connected to BMA180\n\r");
tedparrott6 1:c525baa503a0 36 //pc.printf("BMA180 Version: %d\n\r", readVersion);
jsermita 0:ff755cb08068 37
jsermita 0:ff755cb08068 38 reset();
jsermita 0:ff755cb08068 39
jsermita 0:ff755cb08068 40 byte = readReg(CTRL_REG0);
jsermita 0:ff755cb08068 41 byte |= 0x10; // Set bit4 to 1 to enable self test and unlock image writing
jsermita 0:ff755cb08068 42 writeReg(CTRL_REG0, byte);
jsermita 0:ff755cb08068 43
jsermita 0:ff755cb08068 44 byte = readReg(DIS_I2C); // Read register
jsermita 0:ff755cb08068 45 //pc.printf("\n\rDisable I2C Before: %0.3X ", byte);
jsermita 0:ff755cb08068 46 byte |= 0x01; // Set bit0 to 1 for only SPI
jsermita 0:ff755cb08068 47 writeReg(DIS_I2C, byte); // Set SPI and disable I2C as per pg 31 of datasheet
jsermita 0:ff755cb08068 48 byte = readReg(RANGE);
jsermita 0:ff755cb08068 49 //pc.printf("After: %0.3X", byte);
jsermita 0:ff755cb08068 50
jsermita 0:ff755cb08068 51 byte = readReg(RANGE); // Read register
jsermita 0:ff755cb08068 52 //pc.printf("\n\rRange Before: %0.3X ", byte);
jsermita 0:ff755cb08068 53 byte &= 0xFB; // Set bit3,2,1 to 010 for 2g
jsermita 0:ff755cb08068 54 byte |= 0x02;
jsermita 0:ff755cb08068 55 writeReg(RANGE, byte);
jsermita 0:ff755cb08068 56 byte = readReg(RANGE);
jsermita 0:ff755cb08068 57 //pc.printf("After: %0.3X", byte);
jsermita 0:ff755cb08068 58
jsermita 0:ff755cb08068 59 byte = readReg(CTRL_REG3);
jsermita 0:ff755cb08068 60 //pc.printf("\n\rRegister 3 Before: %0.3X ", byte);
jsermita 0:ff755cb08068 61 byte |= 0x02; // Set bit1 to 1 to enable new data interrupts
jsermita 0:ff755cb08068 62 byte |= 0x40; // Set bit6 to 1 to enable slope mode
jsermita 0:ff755cb08068 63 byte |= 0x80; // Set bit6 to 1 to enable slope alert
jsermita 0:ff755cb08068 64 writeReg(CTRL_REG3, byte);
jsermita 0:ff755cb08068 65 //pc.printf("After: %0.3X", byte);
tedparrott6 1:c525baa503a0 66 //pc.printf("Interrupt is enabled.");
jsermita 0:ff755cb08068 67
jsermita 0:ff755cb08068 68 byte = readReg(CTRL_REG0);
jsermita 0:ff755cb08068 69 byte &= 0xEF; // Set bit4 to 0 to disable self test and lock image writing
jsermita 0:ff755cb08068 70 writeReg(CTRL_REG0, byte);
jsermita 0:ff755cb08068 71
tedparrott6 1:c525baa503a0 72 //pc.printf("\n\rBMA initialization complete.\n\r");
jsermita 0:ff755cb08068 73
jsermita 0:ff755cb08068 74 } else {
tedparrott6 1:c525baa503a0 75 //pc.printf("Not connected to BMA180! ReadVersion: %d ReadID: %d\n\r", readVersion, readID);
jsermita 0:ff755cb08068 76 }
jsermita 0:ff755cb08068 77 }
jsermita 0:ff755cb08068 78
jsermita 0:ff755cb08068 79 void BMA180::reset(void) {
jsermita 0:ff755cb08068 80 writeReg(RESET, 0xB6);
jsermita 0:ff755cb08068 81 wait_ms(10);
tedparrott6 1:c525baa503a0 82 //pc.printf("Soft Reset, EEPROM Copied\n\r");
jsermita 0:ff755cb08068 83 }
jsermita 0:ff755cb08068 84
jsermita 0:ff755cb08068 85 void BMA180::readAxis(void) {
jsermita 0:ff755cb08068 86 int x_msb, y_msb, z_msb;
jsermita 0:ff755cb08068 87 char x_lsb, y_lsb, z_lsb;
jsermita 0:ff755cb08068 88 short ax, ay, az;
jsermita 0:ff755cb08068 89 float afx, afy, afz;
jsermita 0:ff755cb08068 90
jsermita 0:ff755cb08068 91 x_lsb = readReg(ACCXLSB); // Read X LSB register
jsermita 0:ff755cb08068 92 x_msb = readReg(ACCXMSB); // Read X MSB register
jsermita 0:ff755cb08068 93 ax = (x_msb << 8) | x_lsb; // Concatinate X MSB and LSB
jsermita 0:ff755cb08068 94 ax = ax >> 2; // Remove unused first 2 LSB (16 bits to 14 bits)
jsermita 0:ff755cb08068 95 afx = (float)ax*3/16384;
jsermita 0:ff755cb08068 96
jsermita 0:ff755cb08068 97 y_lsb = readReg(ACCYLSB); // Read Y LSB register
jsermita 0:ff755cb08068 98 y_msb = readReg(ACCYMSB); // Read Y MSB register
jsermita 0:ff755cb08068 99 ay = (y_msb << 8) | y_lsb; // Concatinate Y MSB and LSB
jsermita 0:ff755cb08068 100 ay = ay >> 2; // Remove unused first 2 LSB
jsermita 0:ff755cb08068 101 afy = (float)ay*3/16384;
jsermita 0:ff755cb08068 102
jsermita 0:ff755cb08068 103 z_lsb = readReg(ACCZLSB); // Read Z LSB register
jsermita 0:ff755cb08068 104 z_msb = readReg(ACCZMSB); // Read Z MSB register
jsermita 0:ff755cb08068 105 az = (z_msb << 8) | z_lsb; // Concatinate Z MSB and LSB
jsermita 0:ff755cb08068 106 az = az >> 2; // Remove unused first 2 LSB
tedparrott6 1:c525baa503a0 107 afz = (float)az*3/16384;
jsermita 0:ff755cb08068 108
tedparrott6 1:c525baa503a0 109
tedparrott6 1:c525baa503a0 110 //pc.printf("\n\rX: %05f Y: %05f Z: %05f", afx, afy, afz);
jsermita 0:ff755cb08068 111 }
jsermita 0:ff755cb08068 112
jsermita 0:ff755cb08068 113 void BMA180::writeReg(uint8_t address, char data) {
jsermita 0:ff755cb08068 114 address &= 0x7F; // Set bit7 to 0 for write mode
jsermita 0:ff755cb08068 115 _csb = 0; // Select the device
jsermita 0:ff755cb08068 116 wait_us(2);
jsermita 0:ff755cb08068 117 spi.write(address); // Send to data register location
jsermita 0:ff755cb08068 118 wait_us(2);
jsermita 0:ff755cb08068 119 spi.write(data); // Send value to register
jsermita 0:ff755cb08068 120 wait_us(2);
jsermita 0:ff755cb08068 121 _csb = 1; // Deselect the device
jsermita 0:ff755cb08068 122 }
jsermita 0:ff755cb08068 123
jsermita 0:ff755cb08068 124 char BMA180::readReg(uint8_t address) {
jsermita 0:ff755cb08068 125 char byte;
jsermita 0:ff755cb08068 126
jsermita 0:ff755cb08068 127 address |= 0x80; // Set bit7 to 1 for read mode
jsermita 0:ff755cb08068 128 _csb = 0; // Select the device
jsermita 0:ff755cb08068 129 wait_us(2);
jsermita 0:ff755cb08068 130 spi.write(address); // Send to data register location
jsermita 0:ff755cb08068 131 wait_us(2);
jsermita 0:ff755cb08068 132 byte = spi.write(address); // Get data
jsermita 0:ff755cb08068 133 wait_us(2);
jsermita 0:ff755cb08068 134 _csb = 1; // Deselect the device
jsermita 0:ff755cb08068 135 wait_us(2);
jsermita 0:ff755cb08068 136 return byte;
jsermita 0:ff755cb08068 137 }
jsermita 0:ff755cb08068 138
jsermita 0:ff755cb08068 139 void BMA180::disInt(void) {
jsermita 0:ff755cb08068 140 char byte;
jsermita 0:ff755cb08068 141
jsermita 0:ff755cb08068 142 byte = readReg(CTRL_REG0);
jsermita 0:ff755cb08068 143 byte |= 0x10; // Set bit4 to 1 to enable self test and unlock image writing
jsermita 0:ff755cb08068 144 writeReg(CTRL_REG0, byte);
jsermita 0:ff755cb08068 145
jsermita 0:ff755cb08068 146 byte = readReg(CTRL_REG3); // Unlock image writing
jsermita 0:ff755cb08068 147 byte &= 0xFD; // Set bit1 to 0 to disable interrupt
jsermita 0:ff755cb08068 148 writeReg(CTRL_REG3, byte);
jsermita 0:ff755cb08068 149
jsermita 0:ff755cb08068 150 byte = readReg(CTRL_REG0);
jsermita 0:ff755cb08068 151 byte &= 0xEF; // Set bit4 to 0 to disable self test and lock image writing
jsermita 0:ff755cb08068 152 writeReg(CTRL_REG0, byte);
jsermita 0:ff755cb08068 153 }