高度提炼的模拟I2C程序
以下是模拟I2C高度提炼的程序,只要提供GPIO端口、SCL和SDA引脚号、从设备addr,就可以开始使用,基于STM32,对于其他CPU,稍作修改即可。
优点:如果系统中用到了多个模拟I2C通信实例,,就不用每一个模拟I2C实例都编写一套几乎一摸一样的代码,,以下代码对于所有实例都通用。
就像我的系统,很多地方用到了模拟I2C,至少3-4个,有EEPROM,motion运动传感器、ADC等等,,都在不同的引脚上面,但是只用这一套代码。 对于单个I2C,下面也是实用的。
当然:以下代码是根据I2C协议标准编写的,,所有的延时函数都是根据标准所定,,如果不符合您的系统,,可以将delay_us延时加大。
//-------------------------------------------------------------------------------
头文件
----------------------------------------------------------------------------------------- /*
*********************************************************************************************************
* \\'-.__.-'/ | Company : o--Shen Zhen xxxxx Technology Co,.Ltd--o * / (o)(o) \\ | Website : o--http://www.xxxxx .com.cn--o * \\ \\/ / | Copyright : * /'------'\\ | Product :
* /, .... , \\ | File : bsp_SimulateI2C.h
* /// .::::. \\\\\\ | Descript : use GPIOs to Simulate I2C communication * ///\\ :::::: /\\\\\\ | Version : V0.10
* '' ).''''.( `` | Author : nicholasldf
*=(((====)))= | EditTime : 2015-09-06-10:00
********************************************************************************************************* */
#ifndef __BSP_SIMULATE_I2C__ #define __BSP_SIMULATE_I2C__
#include \
//模拟I2C结构体声明
//Simulate I2C Port struct define struct SimuI2cPortType {
GPIO_TypeDef *SCLPort;//GPIO PORT
uint32_t SCLPin; //GPIO PIN GPIO_TypeDef *SDAPort;//GPIO PORT uint32_t SDAPin; //GPIO PIN
uint8_t address; //slave address };
//模拟I2C的SCL、SDA管脚控制宏定义
//SCL output hardware operate
#define SIMUI2C_SCL_SET HAL_GPIO_WritePin(pSimuI2cPort->SCLPort, pSimuI2cPort->SCLPin, GPIO_PIN_SET)
#define SIMUI2C_SCL_CLR HAL_GPIO_WritePin(pSimuI2cPort->SCLPort, pSimuI2cPort->SCLPin, GPIO_PIN_RESET) //SDA output hardware operate
#define SIMUI2C_SDA_SET HAL_GPIO_WritePin(pSimuI2cPort->SDAPort, pSimuI2cPort->SDAPin, GPIO_PIN_SET)
#define SIMUI2C_SDA_CLR HAL_GPIO_WritePin(pSimuI2cPort->SDAPort, pSimuI2cPort->SDAPin, GPIO_PIN_RESET) //SDA input hardware operate
#define SIMUI2C_SDA_IN HAL_GPIO_ReadPin(pSimuI2cPort->SDAPort, pSimuI2cPort->SDAPin)
//simulate i2c APIs
void bsp_SimuI2C_start(struct SimuI2cPortType *pSimuI2cPort); void bsp_SimuI2C_stop(struct SimuI2cPortType *pSimuI2cPort); void bsp_SimuI2C_SandAck(struct SimuI2cPortType *pSimuI2cPort); void bsp_SimuI2C_SandNack(struct SimuI2cPortType *pSimuI2cPort); uint32_t bsp_SimuI2C_ReadAck(struct SimuI2cPortType *pSimuI2cPort); uint8_t bsp_SimuI2C_read_byte(struct SimuI2cPortType *pSimuI2cPort); void
bsp_SimuI2C_write_byte(struct SimuI2cPortType *pSimuI2cPort, uint8_t data);
#endif /* End of module include */
//-------------------------------------------------------------------------------源文件-----------------------------------------------------------------------------------------
/*
*********************************************************************************************************
* \\'-.__.-'/ | Company : o--Shen Zhen xxxxx Technology Co,.Ltd--o * / (o)(o) \\ | Website : o--http://www.xxxxx .com.cn--o * \\ \\/ / | Copyright :
* /'------'\\ | Product :
* /, .... , \\ | File : bsp_SimulateI2C.c
* /// .::::. \\\\\\ | Descript : use GPIOs to Simulate I2C communication * ///\\ :::::: /\\\\\\ | Version : V0.10
* '' ).''''.( `` | Author : nicholasldf
*=(((====)))= | EditTime : 2015-09-06-10:00
********************************************************************************************************* */
#include \#include \
/* 配置SDA管脚为输入方式
********************************************************************************************************* * function : config_sda_in
* Description : config SDA GPIO for input
* Argument(s) : point to struct SimuI2cPortType * Return(s) : none
********************************************************************************************************* */
static void config_sda_in(struct SimuI2cPortType *pSimuI2cPort) {
GPIO_InitTypeDef GPIO_InitStruct;
/* Configure SDA GPIO pin */
GPIO_InitStruct.Pin = pSimuI2cPort->SDAPin; GPIO_InitStruct.Mode = GPIO_MODE_INPUT; GPIO_InitStruct.Pull = GPIO_PULLUP;
GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
HAL_GPIO_Init(pSimuI2cPort->SDAPort, &GPIO_InitStruct); }
/* 配置SDA管脚为输出方式
********************************************************************************************************* * function : config_sda_out
* Description : config SDA GPIO for output
* Argument(s) : point to struct SimuI2cPortType * Return(s) : none
*********************************************************************************************************
*/
static void config_sda_out(struct SimuI2cPortType *pSimuI2cPort) {
GPIO_InitTypeDef GPIO_InitStruct;
/* Configure SDA GPIO pin */
GPIO_InitStruct.Pin = pSimuI2cPort->SDAPin;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP; GPIO_InitStruct.Pull = GPIO_PULLUP;
GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
HAL_GPIO_Init(pSimuI2cPort->SDAPort, &GPIO_InitStruct); }
/* 生成一个I2C的start开始条件,或者restart重新开始条件
********************************************************************************************************* * function : bsp_SimuI2C_start
* Description : generate a i2c start or restart * Argument(s) : point to struct SimuI2cPortType * Return(s) : none
********************************************************************************************************* */
void bsp_SimuI2C_start(struct SimuI2cPortType *pSimuI2cPort) {
//config sda pin output
config_sda_out(pSimuI2cPort);
//here may be a stop SIMUI2C_SCL_SET;
delay_us(1);//SCL setup time for STOP condition, 0.6uS SIMUI2C_SDA_SET;
delay_us(2);//the bus must be free before a new transmission can start, 1.2uS
//start
SIMUI2C_SDA_CLR;
delay_us(1);//SCL hold time for START condition, 0.6uS SIMUI2C_SCL_CLR;
delay_us(1);//SCL low period * 0.5 = 0.65uS }
/* 生成一个I2C的stop停止条件
*********************************************************************************************************
相关推荐: