1
0
mirror of https://bitbucket.org/librepilot/librepilot.git synced 2024-12-12 20:08:48 +01:00
LibrePilot/flight/PiOS/Common/pios_mpu6000.c

434 lines
12 KiB
C
Raw Normal View History

/**
******************************************************************************
* @addtogroup PIOS PIOS Core hardware abstraction layer
* @{
* @addtogroup PIOS_MPU6000 MPU6000 Functions
* @brief Deals with the hardware interface to the 3-axis gyro
* @{
*
* @file pios_mpu000.c
* @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2012.
* @brief MPU6000 6-axis gyro and accel chip
* @see The GNU Public License (GPL) Version 3
*
******************************************************************************
*/
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/* Project Includes */
#include "pios.h"
#if defined(PIOS_INCLUDE_MPU6000)
2012-01-28 07:21:58 +01:00
#include "fifo_buffer.h"
/* Global Variables */
uint32_t pios_spi_gyro;
/* Local Variables */
#define DEG_TO_RAD (M_PI / 180.0)
static void PIOS_MPU6000_Config(struct pios_mpu6000_cfg const * cfg);
static int32_t PIOS_MPU6000_SetReg(uint8_t address, uint8_t buffer);
static int32_t PIOS_MPU6000_GetReg(uint8_t address);
#define PIOS_MPU6000_MAX_DOWNSAMPLE 100
static int16_t pios_mpu6000_buffer[PIOS_MPU6000_MAX_DOWNSAMPLE * sizeof(struct pios_mpu6000_data)];
static t_fifo_buffer pios_mpu6000_fifo;
volatile bool mpu6000_configured = false;
static struct pios_mpu6000_cfg const * cfg;
#define GRAV 9.81f
/**
* @brief Initialize the MPU6000 3-axis gyro sensor.
* @return none
*/
void PIOS_MPU6000_Init(const struct pios_mpu6000_cfg * new_cfg)
{
cfg = new_cfg;
fifoBuf_init(&pios_mpu6000_fifo, (uint8_t *) pios_mpu6000_buffer, sizeof(pios_mpu6000_buffer));
/* Configure the MPU6000 Sensor */
PIOS_SPI_SetPrescalar(pios_spi_gyro, SPI_BaudRatePrescaler_256);
PIOS_MPU6000_Config(cfg);
PIOS_SPI_SetPrescalar(pios_spi_gyro, SPI_BaudRatePrescaler_8);
/* Set up EXTI line */
2012-01-28 07:21:58 +01:00
PIOS_EXTI_Init(cfg->exti_cfg);
}
/**
* @brief Initialize the MPU6000 3-axis gyro sensor
* \return none
* \param[in] PIOS_MPU6000_ConfigTypeDef struct to be used to configure sensor.
*
*/
static void PIOS_MPU6000_Config(struct pios_mpu6000_cfg const * cfg)
{
// Reset chip
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_PWR_MGMT_REG, 0x80) != 0);
PIOS_DELAY_WaitmS(100);
// Reset chip and fifo
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_USER_CTRL_REG, 0x01 | 0x02 | 0x04) != 0);
// Wait for reset to finish
while (PIOS_MPU6000_GetReg(PIOS_MPU6000_USER_CTRL_REG) & 0x07);
//Power management configuration
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_PWR_MGMT_REG, cfg->Pwr_mgmt_clk) != 0) ;
// Interrupt configuration
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_INT_CFG_REG, cfg->interrupt_cfg) != 0) ;
// Interrupt configuration
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_INT_EN_REG, cfg->interrupt_en) != 0) ;
// FIFO storage
#if defined(PIOS_MPU6000_ACCEL)
// Set the accel to 8g mode
while(PIOS_MPU6000_SetReg(PIOS_MPU6000_ACCEL_CFG_REG, 0x10) != 0);
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_FIFO_EN_REG, cfg->Fifo_store | PIOS_MPU6000_ACCEL_OUT) != 0);
#else
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_FIFO_EN_REG, cfg->Fifo_store) != 0);
#endif
// Sample rate divider
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_SMPLRT_DIV_REG, cfg->Smpl_rate_div) != 0) ;
// Digital low-pass filter and scale
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_DLPF_CFG_REG, cfg->filter) != 0) ;
// Digital low-pass filter and scale
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_GYRO_CFG_REG, cfg->gyro_range) != 0) ;
// Interrupt configuration
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_USER_CTRL_REG, cfg->User_ctl) != 0) ;
// Interrupt configuration
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_PWR_MGMT_REG, cfg->Pwr_mgmt_clk) != 0) ;
// Interrupt configuration
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_INT_CFG_REG, cfg->interrupt_cfg) != 0) ;
// Interrupt configuration
while (PIOS_MPU6000_SetReg(PIOS_MPU6000_INT_EN_REG, cfg->interrupt_en) != 0) ;
if((PIOS_MPU6000_GetReg(PIOS_MPU6000_INT_EN_REG)) != cfg->interrupt_en)
return;
mpu6000_configured = true;
}
/**
* @brief Claim the SPI bus for the accel communications and select this chip
* @return 0 if successful, -1 if unable to claim bus
*/
int32_t PIOS_MPU6000_ClaimBus()
{
if(PIOS_SPI_ClaimBus(pios_spi_gyro) != 0)
return -1;
PIOS_SPI_RC_PinSet(pios_spi_gyro,0,0);
return 0;
}
/**
* @brief Release the SPI bus for the accel communications and end the transaction
* @return 0 if successful
*/
int32_t PIOS_MPU6000_ReleaseBus()
{
PIOS_SPI_RC_PinSet(pios_spi_gyro,0,1);
return PIOS_SPI_ReleaseBus(pios_spi_gyro);
}
/**
* @brief Connect to the correct SPI bus
*/
void PIOS_MPU6000_Attach(uint32_t spi_id)
{
pios_spi_gyro = spi_id;
}
/**
* @brief Read a register from MPU6000
* @returns The register value or -1 if failure to get bus
* @param reg[in] Register address to be read
*/
static int32_t PIOS_MPU6000_GetReg(uint8_t reg)
{
uint8_t data;
if(PIOS_MPU6000_ClaimBus() != 0)
return -1;
PIOS_SPI_TransferByte(pios_spi_gyro,(0x80 | reg) ); // request byte
data = PIOS_SPI_TransferByte(pios_spi_gyro,0 ); // receive response
PIOS_MPU6000_ReleaseBus();
return data;
}
/**
* @brief Writes one byte to the MPU6000
* \param[in] reg Register address
* \param[in] data Byte to write
* \return 0 if operation was successful
* \return -1 if unable to claim SPI bus
* \return -2 if unable to claim i2c device
*/
static int32_t PIOS_MPU6000_SetReg(uint8_t reg, uint8_t data)
{
if(PIOS_MPU6000_ClaimBus() != 0)
return -1;
if(PIOS_SPI_TransferByte(pios_spi_gyro, 0x7f & reg) != 0) {
PIOS_MPU6000_ReleaseBus();
return -2;
}
if(PIOS_SPI_TransferByte(pios_spi_gyro, data) != 0) {
PIOS_MPU6000_ReleaseBus();
return -3;
}
PIOS_MPU6000_ReleaseBus();
return 0;
}
/**
* @brief Read current X, Z, Y values (in that order)
* \param[out] int16_t array of size 3 to store X, Z, and Y magnetometer readings
* \returns The number of samples remaining in the fifo
*/
int32_t PIOS_MPU6000_ReadGyros(struct pios_mpu6000_data * data)
{
uint8_t buf[7] = {PIOS_MPU6000_GYRO_X_OUT_MSB | 0x80, 0, 0, 0, 0, 0, 0};
uint8_t rec[7];
if(PIOS_MPU6000_ClaimBus() != 0)
return -1;
if(PIOS_SPI_TransferBlock(pios_spi_gyro, &buf[0], &rec[0], sizeof(buf), NULL) < 0)
return -2;
PIOS_MPU6000_ReleaseBus();
data->gyro_x = rec[1] << 8 | rec[2];
data->gyro_y = rec[3] << 8 | rec[4];
data->gyro_z = rec[5] << 8 | rec[6];
return 0;
}
/*
* @brief Read the identification bytes from the MPU6000 sensor
* \return ID read from MPU6000 or -1 if failure
*/
int32_t PIOS_MPU6000_ReadID()
{
int32_t mpu6000_id = PIOS_MPU6000_GetReg(PIOS_MPU6000_WHOAMI);
if(mpu6000_id < 0)
return -1;
return mpu6000_id;
}
/**
* \brief Reads the data from the MPU6000 FIFO
* \param[out] buffer destination buffer
* \param[in] len maximum number of bytes which should be read
* \note This returns the data as X, Y, Z the temperature
* \return number of bytes transferred if operation was successful
* \return -1 if error during I2C transfer
*/
int32_t PIOS_MPU6000_ReadFifo(struct pios_mpu6000_data * buffer)
{
if(fifoBuf_getUsed(&pios_mpu6000_fifo) < sizeof(*buffer))
return -1;
fifoBuf_getData(&pios_mpu6000_fifo, (uint8_t *) buffer, sizeof(*buffer));
return 0;
}
float PIOS_MPU6000_GetScale()
{
switch (cfg->gyro_range) {
case PIOS_MPU6000_SCALE_250_DEG:
return 1.0f / 131.0f;
case PIOS_MPU6000_SCALE_500_DEG:
return 1.0f / 65.5f;
case PIOS_MPU6000_SCALE_1000_DEG:
return 1.0f / 32.8f;
case PIOS_MPU6000_SCALE_2000_DEG:
return 1.0f / 16.4f;
}
return 0;
}
float PIOS_MPU6000_GetAccelScale()
{
return GRAV / 2048.0f;
}
/**
* @brief Run self-test operation.
* \return 0 if test succeeded
* \return non-zero value if test succeeded
*/
uint8_t PIOS_MPU6000_Test(void)
{
/* Verify that ID matches (MPU6000 ID is 0x69) */
int32_t mpu6000_id = PIOS_MPU6000_ReadID();
if(mpu6000_id < 0)
return -1;
if(mpu6000_id != 0x68);
return -2;
return 0;
}
/**
* @brief Run self-test operation.
* \return 0 if test succeeded
* \return non-zero value if test succeeded
*/
static int32_t PIOS_MPU6000_FifoDepth(void)
{
uint8_t mpu6000_send_buf[3] = {PIOS_MPU6000_FIFO_CNT_MSB | 0x80, 0, 0};
uint8_t mpu6000_rec_buf[3];
if(PIOS_MPU6000_ClaimBus() != 0)
return -1;
if(PIOS_SPI_TransferBlock(pios_spi_gyro, &mpu6000_send_buf[0], &mpu6000_rec_buf[0], sizeof(mpu6000_send_buf), NULL) < 0) {
PIOS_MPU6000_ReleaseBus();
return -1;
}
PIOS_MPU6000_ReleaseBus();
return (mpu6000_rec_buf[1] << 8) | mpu6000_rec_buf[2];
}
/**
* @brief IRQ Handler. Read all the data from onboard buffer
*/
uint32_t mpu6000_irq = 0;
int32_t mpu6000_count;
uint32_t mpu6000_fifo_full = 0;
uint8_t mpu6000_last_read_count = 0;
uint32_t mpu6000_fails = 0;
uint32_t mpu6000_interval_us;
uint32_t mpu6000_time_us;
uint32_t mpu6000_transfer_size;
void PIOS_MPU6000_IRQHandler(void)
{
static uint32_t timeval;
mpu6000_interval_us = PIOS_DELAY_DiffuS(timeval);
timeval = PIOS_DELAY_GetRaw();
if(!mpu6000_configured)
return;
mpu6000_count = PIOS_MPU6000_FifoDepth();
if(mpu6000_count < sizeof(struct pios_mpu6000_data))
return;
if(PIOS_MPU6000_ClaimBus() != 0)
return;
uint8_t mpu6000_send_buf[1+sizeof(struct pios_mpu6000_data)] = {PIOS_MPU6000_FIFO_REG | 0x80, 0, 0, 0, 0, 0, 0, 0, 0};
uint8_t mpu6000_rec_buf[1+sizeof(struct pios_mpu6000_data)];
if(PIOS_SPI_TransferBlock(pios_spi_gyro, &mpu6000_send_buf[0], &mpu6000_rec_buf[0], sizeof(mpu6000_send_buf), NULL) < 0) {
PIOS_MPU6000_ReleaseBus();
mpu6000_fails++;
return;
}
PIOS_MPU6000_ReleaseBus();
struct pios_mpu6000_data data;
if(fifoBuf_getFree(&pios_mpu6000_fifo) < sizeof(data)) {
mpu6000_fifo_full++;
return;
}
// In the case where extras samples backed up grabbed an extra
if (mpu6000_count >= (sizeof(data) * 2)) {
if(PIOS_MPU6000_ClaimBus() != 0)
return;
uint8_t mpu6000_send_buf[1+sizeof(struct pios_mpu6000_data)] = {PIOS_MPU6000_FIFO_REG | 0x80, 0, 0, 0, 0, 0, 0, 0, 0};
uint8_t mpu6000_rec_buf[1+sizeof(struct pios_mpu6000_data)];
if(PIOS_SPI_TransferBlock(pios_spi_gyro, &mpu6000_send_buf[0], &mpu6000_rec_buf[0], sizeof(mpu6000_send_buf), NULL) < 0) {
PIOS_MPU6000_ReleaseBus();
mpu6000_fails++;
return;
}
PIOS_MPU6000_ReleaseBus();
struct pios_mpu6000_data data;
if(fifoBuf_getFree(&pios_mpu6000_fifo) < sizeof(data)) {
mpu6000_fifo_full++;
return;
}
}
#if defined(PIOS_MPU6000_ACCEL)
data.accel_x = mpu6000_rec_buf[1] << 8 | mpu6000_rec_buf[2];
data.accel_y = mpu6000_rec_buf[3] << 8 | mpu6000_rec_buf[4];
data.accel_z = mpu6000_rec_buf[5] << 8 | mpu6000_rec_buf[6];
data.temperature = mpu6000_rec_buf[7] << 8 | mpu6000_rec_buf[8];
data.gyro_x = mpu6000_rec_buf[9] << 8 | mpu6000_rec_buf[10];
data.gyro_y = mpu6000_rec_buf[11] << 8 | mpu6000_rec_buf[12];
data.gyro_z = mpu6000_rec_buf[13] << 8 | mpu6000_rec_buf[14];
#else
data.temperature = mpu6000_rec_buf[1] << 8 | mpu6000_rec_buf[2];
data.gyro_x = mpu6000_rec_buf[3] << 8 | mpu6000_rec_buf[4];
data.gyro_y = mpu6000_rec_buf[5] << 8 | mpu6000_rec_buf[6];
data.gyro_z = mpu6000_rec_buf[7] << 8 | mpu6000_rec_buf[8];
#endif
fifoBuf_putData(&pios_mpu6000_fifo, (uint8_t *) &data, sizeof(data));
mpu6000_irq++;
mpu6000_time_us = PIOS_DELAY_DiffuS(timeval);
}
#endif
/**
* @}
* @}
*/