MR raw bit
Fork of MMA8451Q by
MMA8451Q.cpp@0:6149091f755d, 2012-10-11 (annotated)
- Committer:
- emilmont
- Date:
- Thu Oct 11 10:54:16 2012 +0000
- Revision:
- 0:6149091f755d
- Child:
- 1:d2630136d51e
Package samux acceleromiter library;
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
emilmont | 0:6149091f755d | 1 | #include "MMA8451Q.h" |
emilmont | 0:6149091f755d | 2 | |
emilmont | 0:6149091f755d | 3 | #define REG_WHO_AM_I 0x0D |
emilmont | 0:6149091f755d | 4 | #define REG_CTRL_REG_1 0x2A |
emilmont | 0:6149091f755d | 5 | #define REG_OUT_X_MSB 0x01 |
emilmont | 0:6149091f755d | 6 | #define REG_OUT_Y_MSB 0x03 |
emilmont | 0:6149091f755d | 7 | #define REG_OUT_Z_MSB 0x05 |
emilmont | 0:6149091f755d | 8 | |
emilmont | 0:6149091f755d | 9 | #define UINT14_MAX 16383 |
emilmont | 0:6149091f755d | 10 | |
emilmont | 0:6149091f755d | 11 | MMA8451Q::MMA8451Q(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr) { |
emilmont | 0:6149091f755d | 12 | // activate the peripheral |
emilmont | 0:6149091f755d | 13 | uint8_t data[2] = {REG_CTRL_REG_1, 0x01}; |
emilmont | 0:6149091f755d | 14 | write_regs(data, 2); |
emilmont | 0:6149091f755d | 15 | } |
emilmont | 0:6149091f755d | 16 | |
emilmont | 0:6149091f755d | 17 | MMA8451Q::~MMA8451Q() { } |
emilmont | 0:6149091f755d | 18 | |
emilmont | 0:6149091f755d | 19 | uint8_t MMA8451Q::getWhoAmI() { |
emilmont | 0:6149091f755d | 20 | uint8_t who_am_i = 0; |
emilmont | 0:6149091f755d | 21 | read_regs(REG_WHO_AM_I, &who_am_i, 1); |
emilmont | 0:6149091f755d | 22 | return who_am_i; |
emilmont | 0:6149091f755d | 23 | } |
emilmont | 0:6149091f755d | 24 | |
emilmont | 0:6149091f755d | 25 | int16_t MMA8451Q::getAccX() { |
emilmont | 0:6149091f755d | 26 | return getAccAxis(REG_OUT_X_MSB); |
emilmont | 0:6149091f755d | 27 | } |
emilmont | 0:6149091f755d | 28 | |
emilmont | 0:6149091f755d | 29 | int16_t MMA8451Q::getAccY() { |
emilmont | 0:6149091f755d | 30 | return getAccAxis(REG_OUT_Y_MSB); |
emilmont | 0:6149091f755d | 31 | } |
emilmont | 0:6149091f755d | 32 | |
emilmont | 0:6149091f755d | 33 | int16_t MMA8451Q::getAccZ() { |
emilmont | 0:6149091f755d | 34 | return getAccAxis(REG_OUT_Z_MSB); |
emilmont | 0:6149091f755d | 35 | } |
emilmont | 0:6149091f755d | 36 | |
emilmont | 0:6149091f755d | 37 | void MMA8451Q::getAccAllAxis(int16_t * res) { |
emilmont | 0:6149091f755d | 38 | res[0] = getAccX(); |
emilmont | 0:6149091f755d | 39 | res[1] = getAccY(); |
emilmont | 0:6149091f755d | 40 | res[2] = getAccZ(); |
emilmont | 0:6149091f755d | 41 | } |
emilmont | 0:6149091f755d | 42 | |
emilmont | 0:6149091f755d | 43 | int16_t MMA8451Q::getAccAxis(uint8_t addr) { |
emilmont | 0:6149091f755d | 44 | int16_t acc; |
emilmont | 0:6149091f755d | 45 | uint8_t res[2]; |
emilmont | 0:6149091f755d | 46 | read_regs(addr, res, 2); |
emilmont | 0:6149091f755d | 47 | |
emilmont | 0:6149091f755d | 48 | acc = (res[0] << 6) | (res[1] >> 2); |
emilmont | 0:6149091f755d | 49 | if (acc > UINT14_MAX/2) |
emilmont | 0:6149091f755d | 50 | acc -= UINT14_MAX; |
emilmont | 0:6149091f755d | 51 | |
emilmont | 0:6149091f755d | 52 | return acc; |
emilmont | 0:6149091f755d | 53 | } |
emilmont | 0:6149091f755d | 54 | |
emilmont | 0:6149091f755d | 55 | void MMA8451Q::read_regs(int addr, uint8_t * data, int len) { |
emilmont | 0:6149091f755d | 56 | char t[1] = {addr}; |
emilmont | 0:6149091f755d | 57 | m_i2c.write(m_addr, t, 1, true); |
emilmont | 0:6149091f755d | 58 | m_i2c.read(m_addr, (char *)data, len); |
emilmont | 0:6149091f755d | 59 | } |
emilmont | 0:6149091f755d | 60 | |
emilmont | 0:6149091f755d | 61 | void MMA8451Q::write_regs(uint8_t * data, int len) { |
emilmont | 0:6149091f755d | 62 | m_i2c.write(m_addr, (char *)data, len); |
emilmont | 0:6149091f755d | 63 | } |