mirror of
https://bitbucket.org/librepilot/librepilot.git
synced 2024-11-30 08:24:11 +01:00
137 lines
3.3 KiB
C
137 lines
3.3 KiB
C
/*
|
|
* pios_adxl345.c
|
|
* OpenPilotOSX
|
|
*
|
|
* Created by James Cotton on 1/16/11.
|
|
* Copyright 2011 OpenPilot. All rights reserved.
|
|
*
|
|
*/
|
|
|
|
#include "pios.h"
|
|
|
|
static uint32_t PIOS_SPI_ACCEL;
|
|
|
|
/**
|
|
* @brief Claim the SPI bus for the accel communications and select this chip
|
|
*/
|
|
void PIOS_ADXL345_ClaimBus()
|
|
{
|
|
PIOS_SPI_ClaimBus(PIOS_SPI_ACCEL);
|
|
PIOS_ADXL_ENABLE;
|
|
}
|
|
|
|
/**
|
|
* @brief Release the SPI bus for the accel communications and end the transaction
|
|
*/
|
|
void PIOS_ADXL345_ReleaseBus()
|
|
{
|
|
PIOS_ADXL_DISABLE;
|
|
PIOS_SPI_ReleaseBus(PIOS_SPI_ACCEL);
|
|
}
|
|
|
|
/**
|
|
* @brief Select the sampling rate of the chip
|
|
*
|
|
* This also puts it into high power mode
|
|
*/
|
|
void PIOS_ADXL345_SelectRate(uint8_t rate)
|
|
{
|
|
uint8_t out[2] = {ADXL_RATE_ADDR, rate & 0x0F};
|
|
PIOS_ADXL345_ClaimBus();
|
|
PIOS_SPI_TransferBlock(PIOS_SPI_ACCEL,out,NULL,sizeof(out),NULL);
|
|
PIOS_ADXL345_ReleaseBus();
|
|
}
|
|
|
|
/**
|
|
* @brief Set the range of the accelerometer and set the data to be right justified
|
|
* with sign extension. Also keep device in 4 wire mode.
|
|
*/
|
|
void PIOS_ADXL345_SetRange(uint8_t range)
|
|
{
|
|
uint8_t out[2] = {ADXL_FORMAT_ADDR, (range & 0x03) | ADXL_FULL_RES | ADXL_4WIRE};
|
|
PIOS_ADXL345_ClaimBus();
|
|
PIOS_SPI_TransferBlock(PIOS_SPI_ACCEL,out,NULL,sizeof(out),NULL);
|
|
PIOS_ADXL345_ReleaseBus();
|
|
}
|
|
|
|
/**
|
|
* @brief Set the fifo depth that triggers an interrupt. This will be matched to the oversampling
|
|
*/
|
|
void PIOS_ADXL345_FifoDepth(uint8_t depth)
|
|
{
|
|
uint8_t out[2] = {ADXL_FIFO_ADDR, (depth & 0x1f) | ADXL_FIFO_STREAM};
|
|
PIOS_ADXL345_ClaimBus();
|
|
PIOS_SPI_TransferBlock(PIOS_SPI_ACCEL,out,NULL,sizeof(out),NULL);
|
|
PIOS_ADXL345_ReleaseBus();
|
|
}
|
|
|
|
/**
|
|
* @brief Enable measuring. This also disables the activity sensors (tap or free fall)
|
|
*/
|
|
void PIOS_ADXL345_SetMeasure(uint8_t enable)
|
|
{
|
|
uint8_t out[2] = {ADXL_POWER_ADDR, ADXL_MEAURE};
|
|
PIOS_ADXL345_ClaimBus();
|
|
PIOS_SPI_TransferBlock(PIOS_SPI_ACCEL,out,NULL,sizeof(out),NULL);
|
|
PIOS_ADXL345_ReleaseBus();
|
|
}
|
|
|
|
/**
|
|
* @brief Connect to the correct SPI bus
|
|
*/
|
|
void PIOS_ADXL345_Attach(uint32_t spi_id)
|
|
{
|
|
PIOS_SPI_ACCEL = spi_id;
|
|
}
|
|
|
|
/**
|
|
* @brief Initialize with good default settings
|
|
*/
|
|
void PIOS_ADXL345_Init()
|
|
{
|
|
PIOS_ADXL345_ReleaseBus();
|
|
PIOS_ADXL345_SelectRate(ADXL_RATE_3200);
|
|
PIOS_ADXL345_SetRange(ADXL_RANGE_8G);
|
|
PIOS_ADXL345_FifoDepth(16);
|
|
PIOS_ADXL345_SetMeasure(1);
|
|
}
|
|
|
|
/**
|
|
* @brief Return number of entries in the fifo
|
|
*/
|
|
uint8_t PIOS_ADXL345_FifoElements()
|
|
{
|
|
uint8_t buf[2] = {0,0};
|
|
uint8_t rec[2] = {0,0};
|
|
buf[0] = ADXL_FIFOSTATUS_ADDR | ADXL_READ_BIT ; // Read fifo status
|
|
|
|
PIOS_ADXL345_ClaimBus();
|
|
PIOS_SPI_TransferBlock(PIOS_SPI_ACCEL,&buf[0],&rec[0],sizeof(buf),NULL);
|
|
PIOS_ADXL345_ReleaseBus();
|
|
|
|
return rec[1] & 0x3f;
|
|
}
|
|
|
|
/**
|
|
* @brief Read a single set of values from the x y z channels
|
|
* @returns The number of samples remaining in the fifo
|
|
*/
|
|
uint8_t PIOS_ADXL345_Read(struct pios_adxl345_data * data)
|
|
{
|
|
// To save memory use same buffer for in and out but offset by
|
|
// a byte
|
|
uint8_t buf[9] = {0,0,0,0,0,0,0,0};
|
|
uint8_t rec[9] = {0,0,0,0,0,0,0,0};
|
|
buf[0] = ADXL_X0_ADDR | ADXL_MULTI_BIT | ADXL_READ_BIT ; // Multibyte read starting at X0
|
|
|
|
PIOS_ADXL345_ClaimBus();
|
|
PIOS_SPI_TransferBlock(PIOS_SPI_ACCEL,&buf[0],&rec[0],9,NULL);
|
|
PIOS_ADXL345_ReleaseBus();
|
|
|
|
data->x = rec[1] + (rec[2] << 8);
|
|
data->y = rec[3] + (rec[4] << 8);
|
|
data->z = rec[5] + (rec[6] << 8);
|
|
|
|
return rec[8] & 0x7F; // return number of remaining entries
|
|
}
|