I2C

介绍

对于不同底层驱动的I2C操作实现，统一封装成本文所述hal I2C接口。 hal相关头文件位于目录：[include/aos/hal] hal相关实现位于具体的mcu目录下，如：[platform/mcu/stm32f1xx/hal/]

API列表

API详情

请参考[include/aos/hal/i2c.h]

相关宏定义

#define HAL_WAIT_FOREVER 0xFFFFFFFFU /* Define the wait forever timeout macro */
#define I2C_MODE_MASTER 1            /* i2c communication is master mode */
#define I2C_MODE_SLAVE  2            /* i2c communication is slave mode */

#define I2C_MEM_ADDR_SIZE_8BIT  1    /* i2c memory address size 8bit */
#define I2C_MEM_ADDR_SIZE_16BIT 2    /* i2c memory address size 16bit */

/*
 * Specifies one of the standard I2C bus bit rates for I2C communication
 */
#define I2C_BUS_BIT_RATES_100K  100000
#define I2C_BUS_BIT_RATES_400K  400000
#define I2C_BUS_BIT_RATES_3400K 3400000

/* Addressing mode */
#define I2C_HAL_ADDRESS_WIDTH_7BIT  0 /* 7 bit mode */
#define I2C_HAL_ADDRESS_WIDTH_10BIT 1 /* 10 bit mode */

相关数据结构

i2c_dev_t

typedef struct {
    uint8_t      port;   /* i2c port */
    i2c_config_t config; /* i2c config */
    void        *priv;   /* priv data */
} i2c_dev_t;

i2c_config_t

typedef struct {
    uint32_t address_width;/* Addressing mode: 7 bit or 10 bit */
    uint32_t freq;         /* CLK freq */
    uint8_t  mode;         /* master or slave mode */
    uint16_t dev_addr;     /* slave device addr */
} i2c_config_t;

hal_i2c_init

初始化指定I2C端口

函数原型

int32_t hal_i2c_init(i2c_dev_t *i2c)

参数

返回值

返回成功或失败, 返回0表示I2C初始化成功，非0表示失败

调用示例

#define I2C1_PORT_NUM  1
#define I2C2_PORT_NUM  2
#define I2C2_SLAVE_ADDR  0x50

/* define dev master */
i2c_dev_t i2c_dev_master;
i2c_dev_t i2c_dev_slave;

/* i2c port set */
i2c_dev_master.port = I2C1_PORT_NUM;
/* i2c attr config */
i2c_dev_master.config.mode          = I2C_MODE_MASTER;
i2c_dev_master.config.freq          = I2C_BUS_BIT_RATES_3400K;
i2c_dev_master.config.address_width = I2C_HAL_ADDRESS_WIDTH_7BIT;

i2c_dev_slave.port = I2C2_PORT_NUM;
/* i2c attr config */
i2c_dev_slave.config.mode          = I2C_MODE_SLAVE;
i2c_dev_slave.config.freq          = I2C_BUS_BIT_RATES_3400K;
i2c_dev_slave.config.address_width = I2C_HAL_ADDRESS_WIDTH_7BIT;
i2c_dev_slave.config.dev_addr      = I2C2_SLAVE_ADDR;
/* init master i2c with the given settings */
ret = hal_i2c_init(&i2c_dev_master);
/* init slave i2c with the given settings */
ret = hal_i2c_init(&i2c_dev_slave);

hal_i2c_master_send

master模式下从指定的I2C端口发送数据

函数原型

int32_t hal_i2c_master_send(i2c_dev_t *i2c, uint16_t dev_addr, const uint8_t *data, uint16_t size, uint32_t timeout)

参数

返回值

返回成功或失败, 返回0表示I2C数据发送成功，非0表示失败

调用示例

char pdata_send[10] = {0};
#define I2C2_SLAVE_ADDR  0x50
ret = hal_i2c_master_send(&i2c_dev_master,I2C2_SLAVE_ADDR,pdata_send,10,50);

hal_i2c_master_recv

master模式下从指定的I2C端口接收数据

函数原型

int32_t hal_i2c_master_recv(i2c_dev_t *i2c, uint16_t dev_addr, uint8_t *data,uint16_t size, uint32_t timeout)

参数

返回值

返回成功或失败, 返回0表示成功接收size个数据，非0表示失败

调用示例

char pdata_recv[10] = {0};
#define I2C2_SLAVE_ADDR  0x50
ret = hal_i2c_master_recv(&i2c_dev_master,I2C2_SLAVE_ADDR,pdata_recv,10,50);

hal_i2c_slave_send

slave模式下从指定的I2C端口发送数据

函数原型

int32_t hal_i2c_slave_send(i2c_dev_t *i2c, const uint8_t *data, uint16_t size, uint32_t timeout)

参数

返回值

返回成功或失败, 返回0表示成功发送size个数据，非0表示失败

调用示例

char pdata_send[10] = {0};
ret = hal_i2c_slave_send(&i2c_dev_slave,pdata_send,10,50);

hal_i2c_slave_recv

slave模式下从指定的I2C端口接收数据

函数原型

int32_t hal_i2c_slave_recv(i2c_dev_t *i2c, uint8_t *data, uint16_t size, uint32_t timeout)

参数

返回值

返回成功或失败, 返回0表示成功接收size个数据，非0表示失败

调用示例

char pdata_recv[10] = {0};
ret = hal_i2c_slave_recv(&i2c_dev_slave,pdata_recv,10,50);

hal_i2c_mem_write

向指定的设备内存写数据

函数原型

int32_t hal_i2c_mem_write(i2c_dev_t *i2c, uint16_t dev_addr, uint16_t mem_addr, uint16_t mem_addr_size, const uint8_t *data, uint16_t size, uint32_t timeout)

参数

返回值

返回成功或失败, 返回0表示成功发送size个数据，非0表示失败

调用示例

char pdata[10] = {0};
ret = hal_i2c_mem_write(&i2c_dev_master,0x50,0x20,1,pdata,1,50);

hal_i2c_mem_read

从指定的设备内存读数据

函数原型

int32_t hal_i2c_mem_read(i2c_dev_t *i2c, uint16_t dev_addr, uint16_t mem_addr, uint16_t mem_addr_size, uint8_t  *data, uint16_t size, uint32_t timeout)

参数

返回值

返回成功或失败, 返回0表示成功接收size个数据，非0表示失败

调用示例

char pdata[10] = {0};
ret = hal_i2c_mem_read(&i2c_dev_master,0x50,0x20,1,pdata,1,50);

hal_i2c_finalize

关闭指定I2C端口

函数原型

int32_t hal_i2c_finalize(i2c_dev_t *i2c)

参数

返回值

类型：int 返回成功或失败, 返回0表示I2C关闭成功，非0表示失败。

调用示例

ret = hal_i2c_finalize(&i2c_dev_master);

使用

添加该组件

在相应的platform/mcu的mk内，添加对应hal文件的编译包含。

包含头文件

#include "aos/hal/i2c.h"

使用示例

#include <aos/hal/i2c.h>

#define I2C1_PORT_NUM  1
#define I2C_BUF_SIZE   10
#define I2C_TX_TIMEOUT 10
#define I2C_RX_TIMEOUT 10

#define I2C_DEV_ADDR       0x30f
#define I2C_DEV_ADDR_WIDTH 8

/* define dev */
i2c_dev_t i2c1;

/* data buffer */
char i2c_data_buf[I2C_BUF_SIZE];

int application_start(int argc, char *argv[])
{
    int count   = 0;
    int32_t ret = -1;
    int i       = 0;
    int rx_size = 0;

    /* i2c port set */
    i2c1.port = I2C1_PORT_NUM;

    /* i2c attr config */
    i2c1.config.mode          = I2C_MODE_MASTER;
    i2c1.config.freq          = 30000000;
    i2c1.config.address_width = I2C_DEV_ADDR_WIDTH;
    i2c1.config.dev_addr      = I2C_DEV_ADDR;

    /* init i2c1 with the given settings */
    ret = hal_i2c_init(&i2c1);
    if (ret != 0) {
        printf("i2c1 init error !\n");
    }

    /* init the tx buffer */
    for (i = 0; i < I2C_BUF_SIZE; i++) {
        i2c_data_buf[i] = i + 1;
    }

    /* send 0,1,2,3,4,5,6,7,8,9 by i2c1 */
    ret = hal_i2c_master_send(&i2c1, I2C_DEV_ADDR, i2c_data_buf,
                              I2C_BUF_SIZE, I2C_TX_TIMEOUT);
    if (ret == 0) {
        printf("i2c1 data send succeed !\n");
    }

    ret = hal_i2c_master_recv(&i2c1, I2C_DEV_ADDR, i2c_data_buf,
                              I2C_BUF_SIZE, I2C_RX_TIMEOUT);
    if (ret == 0) {
        printf("i2c1 data received succeed !\n");
    }

    while(1) {
        printf("AliOS Things is working !\n");

        /* sleep 1000ms */
        aos_msleep(1000);
    };
}

注：port为逻辑端口号，其与物理端口号的对应关系见具体的对接实现

移植说明

   新建hal_i2c_xxmcu.c和hal_i2c_xxmcu.h的文件，并将这两个文件放到platform/mcu/xxmcu/hal目录下。在hal_i2c_xxmcu.c中实现所需要的hal函数，hal_i2c_xxmcu.h中放置相关宏定义。<br />       参考platform/mcu/stm32l4xx/src/STM32L496G-Discovery/hal/hal_i2c_stm32l4.c