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LibrePilot/flight/PiOS/Common/pios_bmp085.c
gussy 41fd921b14 Updated BMP085 test code.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@375 ebee16cc-31ac-478f-84a7-5cbb03baadba
2010-03-23 04:01:11 +00:00

253 lines
7.8 KiB
C

/**
******************************************************************************
*
* @file pios_bmp085.c
* @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
* @brief IRQ Enable/Disable routines
* @see The GNU Public License (GPL) Version 3
* @defgroup PIOS_BMP085 BMP085 Functions
* @{
*
*****************************************************************************/
/*
* 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_BMP085)
#if !defined(PIOS_INCLUDE_EXTI)
#error PIOS_EXTI Must be included in the project!
#endif
/* Glocal Variables */
ConversionTypeTypeDef CurrentRead;
xSemaphoreHandle PIOS_BMP085_EOC;
/* Local Variables */
static BMP085CalibDataTypeDef CalibData;
static portBASE_TYPE xHigherPriorityTaskWoken;
/* Straight from the datasheet */
static int32_t X1, X2, X3, B3, B5, B6, P;
static uint32_t B4, B7;
static volatile uint16_t RawTemperature;
static volatile uint32_t RawPressure;
static volatile uint32_t Pressure;
static volatile uint16_t Temperature;
/**
* Initialise the BMP085 sensor
*/
void PIOS_BMP085_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
EXTI_InitTypeDef EXTI_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
/* Enable EOC GPIO clock */
RCC_APB2PeriphClockCmd(PIOS_BMP085_EOC_CLK | RCC_APB2Periph_AFIO, ENABLE);
/* Configure EOC pin as input floating */
GPIO_InitStructure.GPIO_Pin = PIOS_BMP085_EOC_GPIO_PIN;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(PIOS_BMP085_EOC_GPIO_PORT, &GPIO_InitStructure);
/* Configure the End Of Conversion (EOC) interrupt */
GPIO_EXTILineConfig(PIOS_BMP085_EOC_PORT_SOURCE, PIOS_BMP085_EOC_PIN_SOURCE);
EXTI_InitStructure.EXTI_Line = PIOS_BMP085_EOC_EXTI_LINE;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);
/* Enable and set EOC EXTI Interrupt to the lowest priority */
NVIC_InitStructure.NVIC_IRQChannel = PIOS_BMP085_EOC_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = PIOS_BMP085_EOC_PRIO;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* Read all 22 bytes of calibration data in one transfer, this is a very optimised way of doing things */
uint8_t Data[BMP085_CALIB_LEN];
PIOS_BMP085_Read(BMP085_CALIB_ADDR, Data, BMP085_CALIB_LEN);
/* Parameters AC1-AC6 */
CalibData.AC1 = (Data[0] << 8) | Data[1];
CalibData.AC2 = (Data[2] << 8) | Data[3];
CalibData.AC3 = (Data[4] << 8) | Data[5];
CalibData.AC4 = (Data[6] << 8) | Data[7];
CalibData.AC5 = (Data[8] << 8) | Data[9];
CalibData.AC6 = (Data[10] << 8) | Data[11];
/* Parameters B1, B2 */
CalibData.B1 = (Data[12] << 8) | Data[13];
CalibData.B2 = (Data[14] << 8) | Data[15];
/* Parameters MB, MC, MD */
CalibData.MB = (Data[16] << 8) | Data[17];
CalibData.MC = (Data[18] << 8) | Data[19];
CalibData.MD = (Data[20] << 8) | Data[21];
/* Semaphore used by ISR to signal End-Of-Conversion */
vSemaphoreCreateBinary(PIOS_BMP085_EOC);
/* Must start off empty so that first transfer waits for EOC */
xSemaphoreTake(PIOS_BMP085_EOC, portMAX_DELAY);
}
/**
* Start the ADC conversion
* \param[in] PresOrTemp BMP085_PRES_ADDR or BMP085_TEMP_ADDR
* \return Raw ADC value
*/
void PIOS_BMP085_StartADC(ConversionTypeTypeDef Type)
{
/* Start the conversion */
if(Type == TemperatureConv) {
PIOS_BMP085_Write(BMP085_CTRL_ADDR, BMP085_TEMP_ADDR);
} else if(Type == PressureConv) {
PIOS_BMP085_Write(BMP085_CTRL_ADDR, BMP085_PRES_ADDR);
}
CurrentRead = Type;
}
/**
* Read the ADC conversion value (once ADC conversion has completed)
* \param[in] PresOrTemp BMP085_PRES_ADDR or BMP085_TEMP_ADDR
* \return Raw ADC value
*/
void PIOS_BMP085_ReadADC(void)
{
uint8_t Data[3];
Data[0] = 0;
Data[1] = 0;
Data[2] = 0;
/* Read and store the 16bit result */
if(CurrentRead == TemperatureConv) {
/* Read the temperature conversion */
PIOS_BMP085_Read(BMP085_ADC_MSB, Data, 2);
RawTemperature = ((Data[0] << 8) | Data[1]);
X1 = (RawTemperature - CalibData.AC6) * CalibData.AC5 >> 15;
X2 = ((int32_t)CalibData.MC << 11) / (X1 + CalibData.MD);
B5 = X1 + X2;
Temperature = (B5 + 8) >> 4;
} else {
/* Read the pressure conversion */
PIOS_BMP085_Read(BMP085_ADC_MSB, Data, 3);
RawPressure = ((Data[0] << 16) | (Data[1] << 8) | Data[2]) >> (8 - BMP085_OVERSAMPLING);
B6 = B5 - 4000;
X1 = (CalibData.B2 * (B6 * B6 >> 12)) >> 11;
X2 = CalibData.AC2 * B6 >> 11;
X3 = X1 + X2;
B3 = ((((int32_t)CalibData.AC1 * 4 + X3) << BMP085_OVERSAMPLING) + 2) >> 2;
X1 = CalibData.AC3 * B6 >> 13;
X2 = (CalibData.B1 * (B6 * B6 >> 12)) >> 16;
X3 = ((X1 + X2) + 2) >> 2;
B4 = (CalibData.AC4 * (uint32_t) (X3 + 32768)) >> 15;
B7 = ((uint32_t)RawPressure - B3) * (50000 >> BMP085_OVERSAMPLING);
P = B7 < 0x80000000 ? (B7 * 2) / B4 : (B7 / B4) * 2;
X1 = (P >> 8) * (P >> 8);
X1 = (X1 * 3038) >> 16;
X2 = (-7357 * P) >> 16;
Pressure = P + ((X1 + X2 + 3791) >> 4);
}
}
int16_t PIOS_BMP085_GetTemperature(void)
{
return Temperature;
}
int32_t PIOS_BMP085_GetPressure(void)
{
return Pressure;
}
/**
* Reads one or more bytes into a buffer
* \param[in] address BMP085 register address (depends on size)
* \param[out] buffer destination buffer
* \param[in] len number of bytes which should be read
* \return 0 if operation was successful
* \return -1 if error during I2C transfer
* \return -2 if BMP085 blocked by another task (retry it!)
* \return -4 if invalid length
*/
int32_t PIOS_BMP085_Read(uint8_t address, uint8_t *buffer, uint8_t len)
{
/* Try to get the I2C peripheral */
if(PIOS_I2C_LockDevice(I2C_Non_Blocking) < 0) {
/* Request a retry */
return -2;
}
/* Send I2C address and EEPROM address */
/* To avoid issues copy address into temporary buffer */
uint8_t addr_buffer[1] = {(uint8_t)address};
int32_t error = PIOS_I2C_Transfer(I2C_Write_WithoutStop, BMP085_I2C_ADDR, addr_buffer, 1);
/* Now receive byte(s) */
if(!error) {
error = PIOS_I2C_Transfer(I2C_Read, BMP085_I2C_ADDR, buffer, len);
}
/* Release I2C peripheral */
PIOS_I2C_UnlockDevice();
/* Return error status */
return error < 0 ? -1 : 0;
}
/**
* Writes one or more bytes to the BMP085
* \param[in] address Register address
* \param[in] buffer source buffer
* \return 0 if operation was successful
* \return -1 if error during I2C transfer
* \return -2 if BMP085 blocked by another task (retry it!)
*/
int32_t PIOS_BMP085_Write(uint8_t address, uint8_t buffer)
{
/* Try to get the IIC peripheral */
if(PIOS_I2C_LockDevice(I2C_Non_Blocking) < 0) {
/* Request a retry */
return -2;
}
/* Send I2C address and data */
uint8_t WriteBuffer[2];
WriteBuffer[0] = address;
WriteBuffer[1] = buffer;
int32_t error = PIOS_I2C_Transfer(I2C_Write, BMP085_I2C_ADDR, WriteBuffer, 2);
/* Release I2C peripheral */
PIOS_I2C_UnlockDevice();
/* Return error status */
return error < 0 ? -1 : 0;
}
#endif