| 0,0 → 1,157 |
|---|
| #include "adxl345.h" |
| #include "hal_hardware_board.h" |
| #include "hal_SPI.h" |
| |
| /* |
| * Writes the given byte to the register at the address |
| */ |
| void WriteSPI(unsigned char addr, unsigned char data) { |
| halSPISetPolarityPhase(1,1); // ADXL345 operates in SPI(1,1) |
| ADXL_CS_LOW(); |
| spiSendByte(addr & ~ADXL_BYTE_WRITE); |
| spiSendByte(data); |
| ADXL_CS_HIGH(); |
| halSPISetPolarityPhase(0,0); // Revert back to SPI(0,0) |
| } |
| |
| /* |
| * Reads the value of the register at the address |
| */ |
| unsigned char ReadSPI(unsigned char addr) { |
| unsigned char ret; |
| halSPISetPolarityPhase(1,1); // ADXL345 operates in SPI(1,1) |
| ADXL_CS_LOW(); |
| spiSendByte(addr | ADXL_BYTE_READ); |
| spiReadFrame(&ret, 1); |
| ADXL_CS_HIGH(); |
| halSPISetPolarityPhase(0,0); // Revert back to SPI(0,0) |
| return ret; |
| } |
| |
| /* |
| * Reads a 16-bit value of the register at the address |
| */ |
| int Read16SPI(unsigned char addr) { |
| unsigned char recv[2]; |
| int ret; |
| halSPISetPolarityPhase(1,1); // ADXL345 operates in SPI(1,1) |
| ADXL_CS_LOW(); |
| spiSendByte(addr | ADXL_MULTI_BYTE_READ); |
| spiReadFrame(recv, 2); |
| ADXL_CS_HIGH(); |
| halSPISetPolarityPhase(0,0); // Revert back to SPI(0,0) |
| ret = recv[0]; |
| ret |= recv[1] << 8; |
| return ret; |
| } |
| |
| /* |
| * ADXL345 Initialization Function |
| */ |
| unsigned char ADXLInit(void) { |
| unsigned char deviceID; |
| |
| // Check if device exists |
| deviceID = ReadSPI(ADXL345_REG_DEVID); |
| if (deviceID != 0xE5) |
| return 1; |
| |
| // Set FIFO to bypass mode |
| WriteSPI(ADXL345_REG_FIFO_CTL, 0x00); |
| |
| // // Set the INT_INVERT bit in DATA_FORMAT register |
| WriteSPI(ADXL345_REG_DATA_FORMAT, 0x20); |
| |
| ADXLSetRange(ADXL345_RANGE_16_G); |
| |
| ADXLSetDataRate(ADXL345_DATARATE_12_5_HZ); |
| |
| ADXLClearInterrupts(); |
| |
| ADXLStandbyOff(); |
| |
| return 0; |
| } |
| |
| void ADXLStandbyOn(void) { |
| // Turn off measurements |
| WriteSPI(ADXL345_REG_POWER_CTL, 0x00); |
| } |
| |
| void ADXLStandbyOff(void) { |
| // Turn on measurements |
| WriteSPI(ADXL345_REG_POWER_CTL, 0x08); |
| } |
| |
| /* |
| * Sets up and enables the tap interrupt |
| */ |
| void ADXLInitInterrupts(void) { |
| // Set tap acceleration threshold (62.5mg/LSB, 0xFF=16g) |
| WriteSPI(ADXL345_REG_THRESH_TAP, 0x18); |
| |
| // Set maximum tap duration (625us/LSB) |
| WriteSPI(ADXL345_REG_DUR, 0xFF); |
| |
| // Set minimum time for second tap (1.25ms/LSB) |
| WriteSPI(ADXL345_REG_LATENT, 0xFF); |
| |
| // Set maximum time for second tap (1.25ms/LSB) |
| WriteSPI(ADXL345_REG_WINDOW, 0xFF); |
| |
| // Bind single tap to INT1 and double tap to INT2 |
| WriteSPI(ADXL345_REG_INT_MAP, 0x20); |
| |
| // Enable all three axis for tap detection |
| WriteSPI(ADXL345_REG_TAP_AXES, 0x07); |
| |
| // Enable single tap interrupts |
| WriteSPI(ADXL345_REG_INT_ENABLE, 0x40); |
| } |
| |
| /* |
| * Clears any active interrupt flags |
| */ |
| void ADXLClearInterrupts(void) { |
| ReadSPI(ADXL345_REG_ACT_TAP_STATUS); |
| ReadSPI(ADXL345_REG_INT_SOURCE); |
| } |
| |
| /* |
| * Returns sensor data |
| */ |
| void ADXLRead(int *x, int *y, int *z) { |
| *x = Read16SPI(ADXL345_REG_DATAX0); |
| *y = Read16SPI(ADXL345_REG_DATAY0); |
| *z = Read16SPI(ADXL345_REG_DATAZ0); |
| } |
| |
| /* |
| * Sets the sensitivity range (2/4/8/16g) |
| */ |
| void ADXLSetRange(range_t range) { |
| unsigned char data = ReadSPI(ADXL345_REG_DATA_FORMAT); |
| |
| // Set the new sensitivity range |
| data &= ~0x0F; |
| data |= range; |
| |
| // Set the FULL_RES bit |
| data |= 0x08; |
| |
| WriteSPI(ADXL345_REG_DATA_FORMAT, data); |
| } |
| |
| /* |
| * Sets the data rate |
| */ |
| void ADXLSetDataRate(dataRate_t rate) { |
| unsigned char data = rate; |
| |
| #ifdef ADXL345_LOW_POWER_MODE |
| // Set the low power mode bit |
| data |= 0x10; |
| #endif |
| |
| WriteSPI(ADXL345_REG_BW_RATE, data); |
| } |