Renesas MCU使用SCI_I2C驱动HS3003

概述

1 软硬件介绍

1.1 软件版本信息

1.2 认识HS3003

1.2.1 HS3003特性

1.2.2 HS3003寄存器

1.2.2.1 温湿度数据寄存器

1.2.2.2 参数寄存器

1.2.2.3 一个参数配置Demo

1.2.3 温湿度值转换

1.2.4 HS3003应用电路

1.2.4.1 PIN引脚定义

1.2.4.2 sensor 应用电路

1.3 MCU与HS3003对应关系

2 FSP配置项目

2.1 配置项目参数

2.2 生成项目文件架构

3 代码实现

3.1 I2C的库函数

3.1.1 R_SCI_I2C_Open()

3.1.2 R_SCI_I2C_Read()

3.1.3 R_SCI_I2C_Write()

3.2 应用函数接口

3.2.1 初始化函数

3.2.2 读数据函数

3.2.3 写数据函数

3.2.4 回调函数

3.3 源代码文件

4 HS3003驱动实现

4.1 编写驱动程序

4.2 编写测试代码

5 测试

概述

本文主要介绍使用Renesas MCU之i2c读写数据功能，包括硬件资源介绍,FSP配置项目的方法，还介绍了SCI_I2C的接口函数，笔者使用一款I2C接口类型的Sensor(HS3003)作为Device，使用I2C接口驱动该sensor，还编写测试函数验证其功能。

1 软硬件介绍

1.1 软件版本信息

软硬件信息	版本信息
Renesas MCU	R7FA4M2AD3C
Keil	MDK ARM 5.38
FSP 版本	5.3.0
调试工具：st-link	ST-LINK/V2-1

注意：

在Keil MDK中可以更改FSP的版本，方法如下

1.2 认识HS3003

1.2.1 HS3003特性

HS3003是瑞萨公司出品的一款高精度温湿度传感器，下面看看其主要参数：

1.2.2 HS3003寄存器

HS3003采用标准的I2C通信方式，对其寄存器的操作必须遵循标准的I2C时序。现在分析如何操作其寄存器，读取数据。

1.2.2.1 温湿度数据寄存器

温湿度数据寄存器的数据位定义如下，其主要由四个字节组成一个32bit数据， bit-0 和 bit-1为Mask，其主要用来标记当前数据是否有效（mask =0 数据有效），温度数据(低16 bit )： bit-2 ~ bit ~ 15

湿度数据( 高16 bit)： bit-8 ~ bit 13

采样温湿度数据间隔时间根据配置的ADC精度来选取，精度要求越高，采样所需要的时间就越长。那么读取数据时，需要等待的时间就越长。

1.2.2.2 参数寄存器

精度参数如下：

参数寄存器列表

如何配置参数呢？芯片手册给了四个步骤

1.2.2.3 一个参数配置Demo

下面给一个各一个配置参数的范例，配置humidity 的采集精度为12bit, 那么参数设定如下：

bit-10: 0

bit-11: 1

typedef struct
{
   unsigned short res1          : 10;
   unsigned short tempdata      : 2;
   unsigned short res2          : 4;
} stru_para_bit;

typedef struct{
   union
   {
      unsigned short data;
      stru_para_bit para_bit;
   };
}stru_para;


int hs300x_init(void)
{
    int ret;
    unsigned char   buff[4];
    stru_para para;
    
    // step-1 write data from 0x06
    buff[0] = 0x06;
    buff[1] = 0;
    buff[2] = 0;
    ret = write(fd, buff, 3);
    if( ret < 0 )
    {
        printf("read temper cmd to hs3003 register failure.\n");
        return -1;
    }
    
    // step -2: read reg - 0x81
    buff[0] = 0x81;
    ret = write(fd, buff, 1);
    if( ret < 0 )
    {
        printf("read cmd to hs3003 register failure. \r\n");
        return -1;
    }
    
    ret = read(fd, buff, 2);
    if( ret < 0 )
    {
        printf("write cmd to hs3003 register failure.\n");
        return -1;
    }
    printf(" read reg: 0x81 - data0 = %02x data1 = %02x \r\n",buff[0],buff[1]);
    
    //step -3:  write data from 0x46
    para.data = buff[0]<<8 | buff[1];
    para.para_bit.tempdata = 1; 
    buff[0] = 0x46;
    buff[1] = (unsigned char)para.data;
    buff[2] = (unsigned char)(para.data>>8);
    
    ret = write(fd, buff, 3);
    if( ret < 0 )
    {
        printf("write cmd to hs3003 register failure. \r\n");
        return -1;
    }
    printf("write reg: 0x46 - data0 = %02x data1 = %02x \r\n",buff[0],buff[1]);
    
    return 0;
}

1.2.3 温湿度值转换

datasheet中给的转换公式如下：

下面看看在程序中如何实现温湿度值转换的

首先定义一个数据结构


typedef struct
{
   unsigned int mask          : 2;
   unsigned int tempdata      : 14;
   unsigned int humidydata    : 14;
   unsigned int res           : 2;
} Datafetch_bit;

typedef struct{
   union
   {
      unsigned int data;
      Datafetch_bit fetch_bit;
   };
   float tempval;
   float humival;
}hs300x_data;

从温湿度的数据寄存器中读取出来有四个分别为8bit的数据，将该数据拼成一个32bit的数据，在赋值给data, 上述数据结构会自动解析该数据。通过mask位判断数据是否有效。

    phs300x_data->data = ((buff[0] << 24U) |(buff[1] << 16U) |(buff[2] << 8U)|(buff[3]));
    if( phs300x_data->fetch_bit.mask == HS300X_DATA_VALID){
        // get temperature value 
        val = phs300x_data->fetch_bit.tempdata;
        phs300x_data->tempval = (double)val/(double)(HS300X_DATA_FACTOR) * 165.0 - 40;

        printf(" - TM(C): %.2f \r\n", phs300x_data->tempval);

        // get humidity value 
        val = phs300x_data->fetch_bit.humidydata;
        phs300x_data->humival = (double)val/(double)(HS300X_DATA_FACTOR) * 100.0;
        
        printf(" - HM(\%): %.2f \r\n", phs300x_data->humival);
    }

1.2.4 HS3003应用电路

1.2.4.1 PIN引脚定义

传感器封装

pin引脚

1.2.4.2 sensor 应用电路

下面是传感器模块的实际应用电路：

1.3 MCU与HS3003对应关系

MCU接口	HS3003	功能
P409	SDA	I2C数据端口
P408	SCL	I2C时钟接口

2 FSP配置项目

2.1 配置项目参数

1）配置系统时钟，根据硬件特性配置时钟，笔者的板卡上的晶振为12M Hz

2) 在Pins面板配置SCI3，使能I2C,并且配置IO端口

3）在Stacks面板创建i2c的object

配置参数

2.2 生成项目文件架构

点击Generate Project content 按钮，生成项目文件，其文件架构如下：

3 代码实现

3.1 I2C的库函数

3.1.1 R_SCI_I2C_Open()

函数原型：


fsp_err_t R_SCI_I2C_Open	(	i2c_master_ctrl_t *const 	p_api_ctrl,
                                i2c_master_cfg_t const *const 	p_cfg )

函数功能： 打开I2C设备

返回值介绍：

FSP_SUCCESS Requested clock rate was set exactly.
FSP_ERR_ALREADY_OPEN Module is already open.
FSP_ERR_IP_CHANNEL_NOT_PRESENT Channel is not available on this MCU.
FSP_ERR_ASSERTION Parameter check failure due to one or more reasons below:
p_api_ctrl or p_cfg is NULL.
extended parameter is NULL.
Callback parameter is NULL.
Clock rate requested is greater than 400KHz
Invalid IRQ number assigned

3.1.2 R_SCI_I2C_Read()

函数原型：


fsp_err_t R_SCI_I2C_Read	(	i2c_master_ctrl_t *const 	p_api_ctrl,
                                uint8_t *const 	p_dest,
                                uint32_t const 	bytes,
                                bool const 	restart )

函数功能： 从I2C设备执行读取操作。当操作(成功)完成时，调用者将通过回调中的I2C_MASTER_EVENT_RX_COMPLETE收到通知。

返回值：

FSP_SUCCESS Function executed without issue.
FSP_ERR_ASSERTION The parameter p_ctrl, p_dest is NULL, bytes is 0.
FSP_ERR_INVALID_SIZE Provided number of bytes more than uint16_t size (65535) while DTC is used for data transfer.
FSP_ERR_NOT_OPEN Device was not even opened.

3.1.3 R_SCI_I2C_Write()

函数原型：


fsp_err_t R_SCI_I2C_Write	(	i2c_master_ctrl_t *const 	p_api_ctrl,
                                uint8_t *const 	p_src,
                                uint32_t const 	bytes,
                                bool const 	restart )

函数功能： 对I2C设备进行写操作，如果相关通道上已经有正在进行的I2C传输，则此函数将失败。否则，将开始I2C写操作。当用户没有提供回调时，该函数执行阻塞写入。否则，写操作是非阻塞的，并且当操作完成时将通过回调中的I2C_EVENT_TX_COMPLETE通知调用者。

返回值：

FSP_SUCCESS Function executed without issue.
FSP_ERR_ASSERTION p_ctrl, p_src is NULL.
FSP_ERR_INVALID_SIZE Provided number of bytes more than uint16_t size (65535) while DTC is used for data transfer.
FSP_ERR_NOT_OPEN Device was not even opened.

3.2 应用函数接口

创建bsp_i2c.c文件，实现i2c的应用函数接口

3.2.1 初始化函数

代码第24行：打开端口

代码第27行：设置设备地址

3.2.2 读数据函数

代码第54行：从设备中读取数据

代码第57行：判断接收数据是否完成

3.2.3 写数据函数

代码第36行：从设备中写数据

代码第41行：判断写数据是否完成

3.2.4 回调函数

代码第16行：接收当前event

3.3 源代码文件

创建 bsp_i2c.c文件，编写以下代码：

 /*
 FILE NAME  :  bsp_i2c.c
 Description:  i2c interface function 
 Author     :  tangmingfei2013@126.com
 Date       :  2024/06/03
 */
#include "bsp_i2c.h" 
#include "hal_data.h"
 
i2c_master_event_t g_i2c_callback_event;

void g_i2c2_callback (i2c_master_callback_args_t * p_args)
{
    if (NULL != p_args)
    {
        g_i2c_callback_event = p_args->event;
    }
} 

void i2c2_init_para( uint32_t const slaveAddress )
{
    fsp_err_t err;

    err = R_SCI_I2C_Open(&g_i2c2_ctrl, &g_i2c2_cfg);
    assert(FSP_SUCCESS == err);

    err = R_SCI_I2C_SlaveAddressSet(&g_i2c2_ctrl, slaveAddress, I2C_MASTER_ADDR_MODE_7BIT);
    assert(FSP_SUCCESS == err);
}

void i2c2_write_bytes(uint8_t *pbuff, uint16_t length )
{
    unsigned int timeout_ms = 100;
    fsp_err_t err;
    
    err = R_SCI_I2C_Write(&g_i2c2_ctrl, pbuff, length, false);
    assert(FSP_SUCCESS == err);
    
    g_i2c_callback_event = I2C_MASTER_EVENT_ABORTED;
    /* Since there is nothing else to do, block until Callback triggers*/
    while ((I2C_MASTER_EVENT_TX_COMPLETE != g_i2c_callback_event) && timeout_ms)
    {
        R_BSP_SoftwareDelay(1U, BSP_DELAY_UNITS_MILLISECONDS);
        timeout_ms--;;
    }
}

void i2c2_read_bytes(uint8_t *pbuff, uint16_t length )
{
    unsigned int timeout_ms = 100;
    fsp_err_t err;
    
    g_i2c_callback_event = I2C_MASTER_EVENT_ABORTED;
    err = R_SCI_I2C_Read(&g_i2c2_ctrl, pbuff, length, false);
    assert(FSP_SUCCESS == err);
    /* Since there is nothing else to do, block until Callback triggers*/
    while ((I2C_MASTER_EVENT_RX_COMPLETE != g_i2c_callback_event) && timeout_ms)
    {
        R_BSP_SoftwareDelay(1U, BSP_DELAY_UNITS_MILLISECONDS);
        timeout_ms--;;
    }
}
 
/* End of this file */

4 HS3003驱动实现

4.1 编写驱动程序

1）创建hs3003_drv.c文件，编写如下代码：

  /*
 FILE NAME  :  hs3003_drv.c
 Description:  hs3003 driver
 Author     :  tangmingfei2013@126.com
 Date       :  2024/06/03
 */
#include "bsp_i2c.h" 
#include "hal_data.h"
#include "hs3003_drv.h"

int hs300x_init(void)
{
    unsigned char buff[4];
    stru_para para;
    
    i2c2_init_para(HS300X_ADDR);
    
    // step-1 write data from 0x06
    buff[0] = 0x06;
    buff[1] = 0;
    buff[2] = 0;
    
    i2c2_write_bytes(buff, 3);

    // step -2: read reg - 0x81
    buff[0] = 0x81;
    i2c2_write_bytes(buff, 1);
    
    i2c2_read_bytes(buff, 2);
    
    //step -3:  write data from 0x46
    para.data = (unsigned int)(buff[0]<<8 | buff[1]);
    para.para_bit.tempdata = 1; 
    buff[0] = 0x46;
    buff[1] = (unsigned char)para.data;
    buff[2] = (unsigned char)(para.data>>8);
    i2c2_write_bytes( buff, 3);
    
    return 0;
}

int hs300x_read_value(hs300x_data *phs300x_data)
{
    unsigned char buff[4];
    unsigned int val;
    stru_para para;

    // write data to 0xa0
    para.data = 0;
    buff[0] = 0xa0;
    buff[1] = (unsigned char)para.data;
    buff[2] = (unsigned char)(para.data>>8);
    i2c2_write_bytes(buff, 3);
    R_BSP_SoftwareDelay( 1, BSP_DELAY_UNITS_MILLISECONDS);
    
    i2c2_read_bytes(buff, 4);
    phs300x_data->data = (unsigned int)((buff[0] << 24U) |(buff[1] << 16U) |(buff[2] << 8U)|(buff[3]));
    if( phs300x_data->fetch_bit.mask == HS300X_DATA_VALID){
        // get temperature value 
        val = phs300x_data->fetch_bit.tempdata;
        phs300x_data->tempval = (float)((double)val/(double)(HS300X_DATA_FACTOR) * 165.0 - 40);

        // get humidity value 
        val = phs300x_data->fetch_bit.humidydata;
        phs300x_data->humival = (float)((double)val/(double)(HS300X_DATA_FACTOR) * 100.0);

    }
    
    return 0;
}


/* End of this file */

2）创建hs3003_drv.h文件，编写如下代码：

 /*
 FILE NAME  :  hs3003_drv.c
 Description:  hs3003 driver
 Author     :  tangmingfei2013@126.com
 Date       :  2024/06/03
 */
 #ifndef HS3003_DRV_H
 #define HS3003_DRV_H
 #include "hal_data.h"
 
/* hs3003 i2c address */
#define HS300X_ADDR                          (0x44U)

#define HS300X_DATA_VALID                    (0x00U)
#define HS300X_DATA_STALE                    (0x01U)
#define HS300X_STATUS_MASK                   (0xC0000000U)
#define HS300X_STATUS_POS                    (30U)

#define HS300X_DATA_MASK                     (0x3FFFFFFCU)
#define HS300X_HUMI_DATA_MASK                (0x3FFF0000U)
#define HS300X_HUMI_DATA_POS                 (16U)
#define HS300X_TEMP_DATA_MASK                (0x0000FFFCU)
#define HS300X_TEMP_DATA_POS                 (2U)

#define HS300X_REG_R_TRG                     0X06
#define HS300X_REG_W_TRG                     0X46

/* calculation formula, 2^14 - 1 */
#define HS300X_DATA_FACTOR                   (16383U)


typedef struct
{
   unsigned int mask          : 2;
   unsigned int tempdata      : 14;
   unsigned int humidydata    : 14;
   unsigned int res           : 2;
} Datafetch_bit;

typedef struct{
   union
   {
      unsigned int data;
      Datafetch_bit fetch_bit;
   };
   float tempval;
   float humival;
}hs300x_data;

typedef struct
{
   unsigned int res1          : 10;
   unsigned int tempdata      : 2;
   unsigned int res2          : 4;
} stru_para_bit;

typedef struct{
   union
   {
      unsigned int data;
      stru_para_bit para_bit;
   };
}stru_para;

int hs300x_init(void);
int hs300x_read_value(hs300x_data *phs300x_data);

#endif   /* HS3003_DRV_H */

4.2 编写测试代码

代码第48行：初始化hs3003

代码第60行：读取hs3003温湿度值

5 测试

编译代码，然后将代码下载到板卡中，运行代码

当吧手指放到hs3003芯片上，温湿度值就会变化

FSP_SUCCESS	Requested clock rate was set exactly.
FSP_ERR_ALREADY_OPEN	Module is already open.
FSP_ERR_IP_CHANNEL_NOT_PRESENT	Channel is not available on this MCU.
FSP_ERR_ASSERTION	Parameter check failure due to one or more reasons below: p_api_ctrl or p_cfg is NULL. extended parameter is NULL. Callback parameter is NULL. Clock rate requested is greater than 400KHz Invalid IRQ number assigned

FSP_SUCCESS	Function executed without issue.
FSP_ERR_ASSERTION	The parameter p_ctrl, p_dest is NULL, bytes is 0.
FSP_ERR_INVALID_SIZE	Provided number of bytes more than uint16_t size (65535) while DTC is used for data transfer.
FSP_ERR_NOT_OPEN	Device was not even opened.