STM32为基础的模拟I2C通用8bit和16bit读取以及多字节读取

GPIO模拟I2C驱动的通用代码，I2C的寄存器地址有8位和16位的，主要解决了同一个MCU同时处理8位和16位寄存器地址芯片时候的驱动问题。

typedef enum {IIC_8BIT_BASE_ADDR,IIC_16BIT_BASE_ADDR
}iic_bits_e;
typedef struct {uint8_t DevAddr;uint16_t RegAddr;uint8_t data_len;uint8_t * data_buf;uint8_t bit_flag;uint16_t delay;
}iic_param_t;

以上是结构体，作为参数，其中DevAddr是芯片地址，RegAddr是寄存器地址，data_len是写入或者读取的数据长度，data_buf是写入或者读出的数据缓冲区，bit_flag是寄存器位数IIC_8BIT_BASE_ADDR是8位，IIC_16BIT_BASE_ADDR是16位。delay是根据需求读写数据时候的延时。根据芯片需求填写，用不到就填0

下面是用法：

写8bit寄存器

void bq27426_write_data(uint16_t reg, uint8_t * buf, uint8_t len)
{iic_param_t bq27426 = {BQ27426_DEV_ADDR,0,0,NULL,IIC_8BIT_BASE_ADDR,30};bq27426.RegAddr = reg;bq27426.data_buf = buf;bq27426.data_len = len;simulate_i2c_writeblock(&bq27426);}

写16bit寄存器

void cypd3176_write_data(uint16_t reg, uint8_t * buf, uint8_t len)
{iic_param_t cypd3176 = {CYPD3176_DEV_ADDR,0,0,NULL,IIC_16BIT_BASE_ADDR,0};cypd3176.RegAddr = reg;cypd3176.data_buf = buf;cypd3176.data_len = len;simulate_i2c_writeblock(&cypd3176);
}

读8bit寄存器

void bq27426_read_data(uint16_t reg, uint8_t * buf, uint8_t len)
{iic_param_t bq27426 = {BQ27426_DEV_ADDR,0,0,NULL,IIC_8BIT_BASE_ADDR,30};bq27426.RegAddr = reg;bq27426.data_buf = buf;bq27426.data_len = len;simulate_i2c_readblock(&bq27426);}

读16bit寄存器

void cypd3176_read_data(uint16_t reg, uint8_t * buf, uint8_t len)
{iic_param_t cypd3176 = {CYPD3176_DEV_ADDR,0,0,NULL,IIC_16BIT_BASE_ADDR,0};cypd3176.RegAddr = reg;cypd3176.data_buf = buf;cypd3176.data_len = len;simulate_i2c_readblock(&cypd3176);
}

下面是源码

#include "stdio.h"
#include "simulate.h"#define PORT_I2C_SCL GPIOB
#define PIN_I2C_SCL GPIO_Pin_6#define PORT_I2C_SDA GPIOB
#define PIN_I2C_SDA GPIO_Pin_7#define simulate_IIC_SCL PBout(6) 
#define simulate_IIC_SDA PBout(7) 
#define simulate_READ_SDA PBin(7) static void i2c_Delay(void);
static void i2c_PinModeOutput(void);
static void i2c_PinModeInput(void);
static void i2c_SCL(uint8_t stat);
static void i2c_SDA(uint8_t stat);
static uint8_t i2c_ReadSDA(void);
static void i2c_Stop(void);iic_param_t simulate = {simulate_ADDR,0,0,NULL,IIC_16BIT_BASE_ADDR,0
};static void i2c_Delay(void)
{unsigned char t = 3;while (t--);
}static void i2c_PinModeOutput(void)
{GPIO_InitTypeDef GPIO_InitStructure;RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); // ʹ��A�˿�ʱ��GPIO_InitStructure.GPIO_Pin = PIN_I2C_SDA;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;  // �������GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; // �ٶ�50MHzGPIO_Init(PORT_I2C_SDA, &GPIO_InitStructure);	  // ��ʼ��PA0,1
}static void i2c_PinModeInput(void)
{GPIO_InitTypeDef GPIO_InitStructure;RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); // ʹ��A�˿�ʱ��GPIO_InitStructure.GPIO_Pin = PIN_I2C_SDA;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;	  // �������GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; // �ٶ�50MHzGPIO_Init(PORT_I2C_SDA, &GPIO_InitStructure);	  // ��ʼ��PA0,1
}static void i2c_SCL(uint8_t stat)
{if (stat){simulate_IIC_SCL = 1;}else{simulate_IIC_SCL = 0;}
}static void i2c_SDA(uint8_t stat)
{if (stat){simulate_IIC_SDA = 1;}else{simulate_IIC_SDA = 0;}
}static uint8_t i2c_ReadSDA(void)
{if (simulate_READ_SDA){return 1;}else{return 0;}
}void i2c_Start(void)
{i2c_PinModeOutput();i2c_SDA(1);i2c_Delay();i2c_SCL(1);i2c_Delay();i2c_SDA(0);i2c_Delay();i2c_SCL(0);i2c_Delay();
}void i2c_Stop(void)
{i2c_PinModeOutput();i2c_SCL(0);i2c_SDA(0);i2c_Delay();i2c_SCL(1);i2c_Delay();i2c_SDA(1);i2c_Delay();
}void i2c_WriteByte(uint8_t _ucByte)
{uint8_t i;i2c_PinModeOutput();i2c_SCL(0);i2c_Delay();for (i = 0; i < 8; i++){if (_ucByte & 0x80){i2c_SDA(1);}else{i2c_SDA(0);}_ucByte = _ucByte << 1;i2c_SCL(1);i2c_Delay();i2c_SCL(0);i2c_Delay();}i2c_SDA(1);
}uint8_t i2c_ReadByte(void)
{uint8_t i;uint8_t recv = 0;i2c_PinModeOutput();i2c_SDA(1);i2c_Delay();i2c_PinModeInput();for (i = 0; i < 8; i++){recv = recv << 1;i2c_SCL(1);i2c_Delay();if (i2c_ReadSDA()){recv |= 0x01;}else{recv |= 0x00;}i2c_SCL(0);i2c_Delay();}return recv;
}void i2c_Ack(void)
{i2c_PinModeOutput();i2c_SCL(0);i2c_SDA(0);i2c_Delay();i2c_SCL(1);i2c_Delay();i2c_SCL(0);
}void i2c_NAck(void)
{i2c_PinModeOutput();i2c_SCL(0);i2c_SDA(1);i2c_Delay();i2c_SCL(1);i2c_Delay();i2c_SCL(0);
}uint8_t i2c_CheckAck(void)
{uint8_t time = 0;i2c_PinModeOutput();i2c_SDA(1);i2c_Delay();i2c_SCL(1);i2c_Delay();i2c_PinModeInput();while (i2c_ReadSDA()){time++;if (time >= 100){return 1;}}i2c_SCL(0);return 0;
}#define I2C_WR 0x00
#define I2C_RD 0x01
#define ACK 0
#define NOACK 1void simulate_i2c_init(void)
{GPIO_InitTypeDef GPIO_InitStructure;RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOB, &GPIO_InitStructure);			  GPIO_SetBits(GPIOB, GPIO_Pin_6 | GPIO_Pin_7);
}uint8_t iic_chip_select(iic_param_t *param, uint8_t rw_flag)
{uint16_t i = 0;if (param->data_len > 40){return 0xf1;}if (param->data_buf == NULL){return 0xF2;}for (i = 0; i < 3; i++){i2c_Start();i2c_WriteByte((param->DevAddr << 1) | rw_flag); if (i2c_CheckAck() == ACK){break;}}if (i >= 3){i2c_Stop();return 0xf1;}return 0;
}uint8_t simulate_i2c_writeblock(iic_param_t *param)
{uint16_t i;if (0 != iic_chip_select(param, I2C_WR)){return 0xF1;}if (IIC_16BIT_BASE_ADDR == param->bit_flag){i2c_WriteByte((param->RegAddr & 0xFF00) >> 8);if (i2c_CheckAck() == NOACK){i2c_Stop();return 0xf7;}}i2c_WriteByte(param->RegAddr & 0x00FF);if (i2c_CheckAck() == NOACK){i2c_Stop();return 0xf3;}for (i = 0; i < param->data_len; i++){i2c_WriteByte(param->data_buf[i]);if (i2c_CheckAck() == NOACK){i2c_Stop();return 0xf4;}}i2c_Stop();for (i = 0; i < 100; i++){i2c_Delay();}return 0;
}uint8_t simulate_i2c_readblock(iic_param_t *param)
{uint16_t i;int16_t j;if (0 != iic_chip_select(param, I2C_WR)){return 0xF1;}/* 发送地址 */if (IIC_16BIT_BASE_ADDR == param->bit_flag){i2c_WriteByte((param->RegAddr & 0xFF00) >> 8);if (i2c_CheckAck() == NOACK){i2c_Stop();return 0xf7;}}i2c_WriteByte(param->RegAddr & 0x00FF);if (i2c_CheckAck() == NOACK){i2c_Stop();return 0xf8;}if (0 != iic_chip_select(param, I2C_RD)){return 0xF1;}for (i = 0; i < param->data_len - 1; i++){for (j = 0; j < param->delay; j++){i2c_Delay();}param->data_buf[i] = i2c_ReadByte();for (j = 0; j < param->delay; j++){i2c_Delay();}i2c_Ack();}for (j = 0; j < param->delay; j++){i2c_Delay();}param->data_buf[param->data_len - 1] = i2c_ReadByte();i2c_NAck();i2c_Stop();return 0;
}

#ifndef __IIC_DRIVER_H__
#define __IIC_DRIVER_H__#include "sys.h"
#include "stdlib.h"	#define simulate_ADDR  (0x5F)typedef enum {IIC_8BIT_BASE_ADDR,IIC_16BIT_BASE_ADDR
}iic_bits_e;
typedef struct {uint8_t DevAddr;uint16_t RegAddr;uint8_t data_len;uint8_t * data_buf;uint8_t bit_flag;uint16_t delay;
}iic_param_t;void simulate_i2c_init(void);
uint8_t simulate_i2c_readblock(iic_param_t * param);
uint8_t simulate_i2c_writeblock(iic_param_t * param);#endif 

如果找不到PBout可用下面的头文件，其他平台可以自己实现设置管脚的输入和输出模式替换掉文中的PBout PBin的接口

/* Includes ------------------------------------------------------------------*/
#ifndef __SYS_H
#define __SYS_H	
#include "stm32f10x.h"#define BITBAND(addr, bitnum) ((addr & 0xF0000000)+0x2000000+((addr &0xFFFFF)<<5)+(bitnum<<2)) 
#define MEM_ADDR(addr)  *((volatile unsigned long  *)(addr)) 
#define BIT_ADDR(addr, bitnum)   MEM_ADDR(BITBAND(addr, bitnum))#define GPIOA_ODR_Addr    (GPIOA_BASE+12) //0x4001080C 
#define GPIOB_ODR_Addr    (GPIOB_BASE+12) //0x40010C0C 
#define GPIOC_ODR_Addr    (GPIOC_BASE+12) //0x4001100C 
#define GPIOD_ODR_Addr    (GPIOD_BASE+12) //0x4001140C 
#define GPIOE_ODR_Addr    (GPIOE_BASE+12) //0x4001180C 
#define GPIOF_ODR_Addr    (GPIOF_BASE+12) //0x40011A0C    
#define GPIOG_ODR_Addr    (GPIOG_BASE+12) //0x40011E0C    #define GPIOA_IDR_Addr    (GPIOA_BASE+8) //0x40010808 
#define GPIOB_IDR_Addr    (GPIOB_BASE+8) //0x40010C08 
#define GPIOC_IDR_Addr    (GPIOC_BASE+8) //0x40011008 
#define GPIOD_IDR_Addr    (GPIOD_BASE+8) //0x40011408 
#define GPIOE_IDR_Addr    (GPIOE_BASE+8) //0x40011808 
#define GPIOF_IDR_Addr    (GPIOF_BASE+8) //0x40011A08 
#define GPIOG_IDR_Addr    (GPIOG_BASE+8) //0x40011E08 #define PAout(n)   BIT_ADDR(GPIOA_ODR_Addr,n)
#define PAin(n)    BIT_ADDR(GPIOA_IDR_Addr,n)#define PBout(n)   BIT_ADDR(GPIOB_ODR_Addr,n) 
#define PBin(n)    BIT_ADDR(GPIOB_IDR_Addr,n)#define PCout(n)   BIT_ADDR(GPIOC_ODR_Addr,n)
#define PCin(n)    BIT_ADDR(GPIOC_IDR_Addr,n)#define PDout(n)   BIT_ADDR(GPIOD_ODR_Addr,n) 
#define PDin(n)    BIT_ADDR(GPIOD_IDR_Addr,n) #define PEout(n)   BIT_ADDR(GPIOE_ODR_Addr,n) 
#define PEin(n)    BIT_ADDR(GPIOE_IDR_Addr,n)#define PFout(n)   BIT_ADDR(GPIOF_ODR_Addr,n)
#define PFin(n)    BIT_ADDR(GPIOF_IDR_Addr,n) #define PGout(n)   BIT_ADDR(GPIOG_ODR_Addr,n)
#define PGin(n)    BIT_ADDR(GPIOG_IDR_Addr,n)  #endif