1
0
mirror of https://bitbucket.org/librepilot/librepilot.git synced 2024-12-13 20:48:42 +01:00
LibrePilot/flight/PiOS/Common/pios_adxl345.c
stac 3fda65c5d3 hwinit: Convert SPI drivers to dynamic init
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@2772 ebee16cc-31ac-478f-84a7-5cbb03baadba
2011-02-12 22:19:50 +00:00

121 lines
3.0 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 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
}