一個穩(wěn)定可靠的STM32 I2C程序

1、/*File : i2c.hPurpose : */#ifndef _I2C_H_#define _I2C_H_/* Includes */* Defines */#define SENSORS_I2C I2C2#define I2C_SPEED 400000#define I2C_OWN_ADDRESS 0x00#define I2C_Config() I2cMaster_Init(); /* Prototypes */void I2cMaster_Init(void);unsigned long Sensors_I2C_WriteRegister(unsigned char Address

2、, unsigned char RegisterAddr, unsigned short RegisterLen, const unsigned char *RegisterValue);unsigned long Sensors_I2C_ReadRegister(unsigned char Address, unsigned char RegisterAddr, unsigned short RegisterLen, unsigned char *RegisterValue);int Sensors_I2C_WriteRegister_swap(unsigned char slave_add

3、r,unsigned char reg_addr,unsigned char len, unsigned char *data_ptr);int Sensors_I2C_ReadRegister_swap(unsigned char slave_addr,unsigned char reg_addr,unsigned char len, unsigned char *data_ptr);int I2C_Reset_User();#endif / _I2C_H_/*File : i2c.cPurpose : I2c 3 to communicate with the sensorsAuthor

4、: * Includes */#include <stdio.h>#include "stm32l1xx.h"#include "i2c.h"#include "gpio.h"#include "log.h"#include "discover_board.h"#include "main.h"/* Defines */#define I2Cx_FLAG_TIMEOUT (uint32_t) 900)#define I2Cx_LONG_TIMEOUT (uint3

5、2_t)(300 * I2Cx_FLAG_TIMEOUT)#define SENSORS_I2C_SCL_GPIO_PORT GPIOB#define SENSORS_I2C_SCL_GPIO_CLK RCC_AHBPeriph_GPIOB#define SENSORS_I2C_SCL_GPIO_PIN GPIO_Pin_10#define SENSORS_I2C_SCL_GPIO_PINSOURCE GPIO_PinSource10 #define SENSORS_I2C_SDA_GPIO_PORT GPIOB#define SENSORS_I2C_SDA_GPIO_CLK RCC_AHBP

6、eriph_GPIOB#define SENSORS_I2C_SDA_GPIO_PIN GPIO_Pin_11#define SENSORS_I2C_SDA_GPIO_PINSOURCE GPIO_PinSource11#define SENSORS_I2C_RCC_CLK RCC_APB1Periph_I2C2#define SENSORS_I2C_AF GPIO_AF_I2C2#define WAIT_FOR_FLAG(flag, value, timeout, errorcode) I2CTimeout = timeout; while(I2C_GetFlagStatus(SENSORS

7、_I2C, flag) != value) if(I2CTimeout-) = 0) return I2Cx_TIMEOUT_UserCallback(errorcode); #define CLEAR_ADDR_BIT I2C_ReadRegister(SENSORS_I2C, I2C_Register_SR1); I2C_ReadRegister(SENSORS_I2C, I2C_Register_SR2); /* Globals */* Prototypes */* Function */static uint32_t I2Cx_TIMEOUT_UserCallback(char val

8、ue);void I2cMaster_Init(void) GPIO_InitTypeDef GPIO_InitStructure; I2C_InitTypeDef I2C_InitStructure; /* Enable I2Cx clock */ RCC_APB1PeriphClockCmd(SENSORS_I2C_RCC_CLK, ENABLE); /* Enable I2C GPIO clock */ RCC_AHBPeriphClockCmd(SENSORS_I2C_SCL_GPIO_CLK | SENSORS_I2C_SDA_GPIO_CLK, ENABLE); /* Config

9、ure I2Cx pin: SCL -*/ GPIO_InitStructure.GPIO_Pin = SENSORS_I2C_SCL_GPIO_PIN; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz; GPIO_InitStructure.GPIO_OType = GPIO_OType_OD; GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; /* Connect pins to Periph */ GP

10、IO_PinAFConfig(SENSORS_I2C_SCL_GPIO_PORT, SENSORS_I2C_SCL_GPIO_PINSOURCE, SENSORS_I2C_AF); GPIO_Init(SENSORS_I2C_SCL_GPIO_PORT, &GPIO_InitStructure); /* Configure I2Cx pin: SDA -*/ GPIO_InitStructure.GPIO_Pin = SENSORS_I2C_SDA_GPIO_PIN; /* Connect pins to Periph */ GPIO_PinAFConfig(SENSORS_I2C_S

11、DA_GPIO_PORT, SENSORS_I2C_SDA_GPIO_PINSOURCE, SENSORS_I2C_AF); GPIO_Init(SENSORS_I2C_SDA_GPIO_PORT, &GPIO_InitStructure); I2C_DeInit(SENSORS_I2C); I2C_InitStructure.I2C_Mode = I2C_Mode_I2C; I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2; I2C_InitStructure.I2C_OwnAddress1 = I2C_OWN_ADDRESS; I2

12、C_InitStructure.I2C_Ack = I2C_Ack_Enable; I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit; I2C_InitStructure.I2C_ClockSpeed = I2C_SPEED; /* Enable the I2C peripheral */ I2C_Cmd(SENSORS_I2C, ENABLE); /* Initialize the I2C peripheral */ I2C_Init(SENSORS_I2C, &I2C_InitStruc

13、ture);/* * brief Basic management of the timeout situation. * param None. * retval None. */static uint32_t I2Cx_TIMEOUT_UserCallback(char value) /* The following code allows I2C error recovery and return to normal communication if the error source doesn't still exist (ie. hardware issue.) */ I2C

14、_InitTypeDef I2C_InitStructure; I2C_GenerateSTOP(SENSORS_I2C, ENABLE); I2C_SoftwareResetCmd(SENSORS_I2C, ENABLE); I2C_SoftwareResetCmd(SENSORS_I2C, DISABLE); I2C_DeInit(SENSORS_I2C); I2C_InitStructure.I2C_Mode = I2C_Mode_I2C; I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2; I2C_InitStructure.I2C_O

15、wnAddress1 = I2C_OWN_ADDRESS; I2C_InitStructure.I2C_Ack = I2C_Ack_Enable; I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit; I2C_InitStructure.I2C_ClockSpeed = I2C_SPEED; /* Enable the I2C peripheral */ I2C_Cmd(SENSORS_I2C, ENABLE); /* Initialize the I2C peripheral */ I2C_Init

16、(SENSORS_I2C, &I2C_InitStructure); #ifdef User_debug MPL_LOGI("I2C Restarted.n");#endif return 1;int I2C_Reset_User() return I2Cx_TIMEOUT_UserCallback(0); /* * brief Writes a Byte to a given register to the sensors through the control interface (I2C) * param RegisterAddr: The address (

17、location) of the register to be written. * param RegisterValue: the Byte value to be written into destination register. * retval 0 if correct communication, else wrong communication */unsigned long Sensors_I2C_WriteRegister(unsigned char Address, unsigned char RegisterAddr, unsigned short RegisterLe

18、n, const unsigned char *RegisterValue) uint32_t result = 0; uint32_t i = RegisterLen; _IO uint32_t I2CTimeout = I2Cx_LONG_TIMEOUT; /RegisterValue = RegisterValue + (RegisterLen - 1); /* Wait for the busy flag to be cleared */ WAIT_FOR_FLAG (I2C_FLAG_BUSY, RESET, I2Cx_LONG_TIMEOUT, 1); /* Start the c

19、onfig sequence */ I2C_GenerateSTART(SENSORS_I2C, ENABLE); /* Wait for the start bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_SB, SET, I2Cx_FLAG_TIMEOUT, 2); /* Transmit the slave address and enable writing operation */ I2C_Send7bitAddress(SENSORS_I2C, (Address<<1), I2C_Direction_Transmitter); /* W

20、ait for address bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_ADDR, SET, I2Cx_FLAG_TIMEOUT, 3); /* clear the ADDR interrupt bit - this is done by reading SR1 and SR2*/ CLEAR_ADDR_BIT /* Wait for address bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_TXE, SET, I2Cx_FLAG_TIMEOUT, 4); /* Transmit the first addres

21、s for write operation */ I2C_SendData(SENSORS_I2C, RegisterAddr); while (i-) /* Wait for address bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_TXE, SET, I2Cx_FLAG_TIMEOUT, 5); /* Prepare the register value to be sent */ /I2C_SendData(SENSORS_I2C, *RegisterValue-); I2C_SendData(SENSORS_I2C, *RegisterValue

22、+); /* Wait for address bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_BTF, SET, I2Cx_FLAG_TIMEOUT, 6); /* End the configuration sequence */ I2C_GenerateSTOP(SENSORS_I2C, ENABLE); /* Return the verifying value: 0 (Passed) or 1 (Failed) */ return result; unsigned long Sensors_I2C_ReadRegister(unsigned char

23、 Address, unsigned char RegisterAddr, unsigned short RegisterLen, unsigned char *RegisterValue) uint32_t result = 0; uint8_t bytesRemaining = RegisterLen; _IO uint32_t I2CTimeout = I2Cx_LONG_TIMEOUT; /* Wait for the busy flag to be cleared */ WAIT_FOR_FLAG (I2C_FLAG_BUSY, RESET, I2Cx_LONG_TIMEOUT, 7

24、); /* Start the config sequence */ I2C_GenerateSTART(SENSORS_I2C, ENABLE); /* Wait for the start bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_SB, SET, I2Cx_FLAG_TIMEOUT, 8); /* Transmit the slave address and enable writing operation */ I2C_Send7bitAddress(SENSORS_I2C, (Address<<1), I2C_Direction_T

25、ransmitter); /* Wait for the start bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_ADDR, SET, I2Cx_FLAG_TIMEOUT, 9); /* clear the ADDR interrupt bit - this is done by reading SR1 and SR2*/ CLEAR_ADDR_BIT; /* Wait for address bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_TXE, SET, I2Cx_FLAG_TIMEOUT, 10); /* Tran

26、smit the register address to be read */ I2C_SendData(SENSORS_I2C, RegisterAddr); /* Wait for address bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_TXE, SET, I2Cx_FLAG_TIMEOUT, 11); /*!< Send START condition a second time */ I2C_GenerateSTART(SENSORS_I2C, ENABLE); /* Wait for the start bit to be set */

27、 WAIT_FOR_FLAG (I2C_FLAG_SB, SET, I2Cx_FLAG_TIMEOUT, 12); /*!< Send address for read */ I2C_Send7bitAddress(SENSORS_I2C, (Address<<1), I2C_Direction_Receiver); /* Wait for the start bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_ADDR, SET, I2Cx_FLAG_TIMEOUT, 13); if (RegisterLen = 1) /*!< Disa

28、ble Acknowledgment */ I2C_AcknowledgeConfig(SENSORS_I2C, DISABLE); /* clear the ADDR interrupt bit - this is done by reading SR1 and SR2*/ CLEAR_ADDR_BIT; /*!< Send STOP Condition */ I2C_GenerateSTOP(SENSORS_I2C, ENABLE); /* Wait for the RXNE bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_RXNE, SET, I2

29、Cx_FLAG_TIMEOUT, 14); /bytesRemaining-; /RegisterValuebytesRemaining = I2C_ReceiveData(SENSORS_I2C); RegisterValue0 = I2C_ReceiveData(SENSORS_I2C); else if( RegisterLen = 2) /*!< Disable Acknowledgment */ I2C_AcknowledgeConfig(SENSORS_I2C, DISABLE); /* Set POS bit */ SENSORS_I2C->CR1 |= I2C_CR

30、1_POS; /* clear the ADDR interrupt bit - this is done by reading SR1 and SR2*/ CLEAR_ADDR_BIT; /* Wait for the buffer full bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_BTF, SET, I2Cx_FLAG_TIMEOUT, 15); /*!< Send STOP Condition */ I2C_GenerateSTOP(SENSORS_I2C, ENABLE); /* Read 2 bytes */ /bytesRemaini

31、ng-; /RegisterValuebytesRemaining = I2C_ReceiveData(SENSORS_I2C); /RegisterValuebytesRemaining = I2C_ReceiveData(SENSORS_I2C); RegisterValue0 = I2C_ReceiveData(SENSORS_I2C); RegisterValue1 = I2C_ReceiveData(SENSORS_I2C); else /* more than 2 bytes */ /* clear the ADDR interrupt bit - this is done by

32、reading SR1 and SR2*/ CLEAR_ADDR_BIT; while(bytesRemaining) if( bytesRemaining = 3) /* Wait for the buffer full bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_BTF, SET, I2Cx_FLAG_TIMEOUT, 16); /*!< Disable Acknowledgment */ I2C_AcknowledgeConfig(SENSORS_I2C, DISABLE); /* Read 1 bytes */ bytesRemaining-

33、; /RegisterValuebytesRemaining = I2C_ReceiveData(SENSORS_I2C); *RegisterValue+ = I2C_ReceiveData(SENSORS_I2C); /*!< Send STOP Condition */ I2C_GenerateSTOP(SENSORS_I2C, ENABLE); /* Read 1 bytes */ bytesRemaining-; /RegisterValuebytesRemaining = I2C_ReceiveData(SENSORS_I2C); *RegisterValue+ = I2C_

34、ReceiveData(SENSORS_I2C); /* Wait for the buffer full bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_RXNE, SET, I2Cx_FLAG_TIMEOUT, 17); /* Read 1 bytes */ bytesRemaining-; /RegisterValuebytesRemaining = I2C_ReceiveData(SENSORS_I2C); *RegisterValue+ = I2C_ReceiveData(SENSORS_I2C); else /* Wait for the RXNE

35、 bit to be set */ WAIT_FOR_FLAG (I2C_FLAG_RXNE, SET, I2Cx_FLAG_TIMEOUT, 18); /* Read 2 bytes */ bytesRemaining-; /RegisterValuebytesRemaining = I2C_ReceiveData(SENSORS_I2C); *RegisterValue+ = I2C_ReceiveData(SENSORS_I2C); /* Clear BTF flag */ I2C_ClearFlag(SENSORS_I2C, I2C_FLAG_BTF); /* Wait for the busy flag to be cleared */ WAIT_FOR_FLAG (I2C_FLAG_BUSY, RESET, I2Cx_LONG_TIMEOUT, 19); /*!< Re-Enable Acknowledgment to be ready for another reception */ I2C_AcknowledgeConfig(SENSORS_I2C, ENABLE); /Disable POS - TODO SENSORS_I2C->CR1 &= I