如何利用GD32F310读取HDC1080环境温湿度

我拿到的开发板实际板载的MCU是GD32F310G8，QFN28pin封装，基于ARM CORTEX M4内核，主频72MHz，芯片内置64KB flash，8KB SRAM，两路I2C外设。

本次试用目的是利用GD32F310的I2C0实现对HDC1080的初始化及读取环境温湿度，并利用UART口在电脑上显示出来。

1、新建工程

①首先建立一个新的项目文件夹，并在此文件夹下建立对应子文件夹，我建立的文件如下图所示，这个依个人习惯会有不同：

② Document文件夹中存放对项目的说明文件readme.txt；将系统支持包中的GD32F3x0_Firmware_Library_V2.2.0/Firmware文件夹中的内容复制到Libraries文件夹中；Listing/Output文件夹用于存放项目编译时生成的目标文件及list文件，在MDK的魔术棒中进行设置路径；users文件夹中存放main文件及我们自已写的代码；Project文件夹中存放MDK项目文件；

③打开MDK keil5，首先要先导入GD32F310G文件支持包。

④建立新的项目，选择所使用的ＭＣＵ，我们选择GD32F330G8，如下图所示

⑤新项目中建立如下文件组，并导入启动文件和外设支持包。

⑥点击魔术棒工具进行项目设置。在C/C++选项中添加include文件路径；

⑦点击Debug选项进行GDLink的设置，要选择CMSIS_DAP Debugger，并将Reset and Run打勾。

⑧这样整个项目的配置基本就结束了，可以在main.c文件中建立一个空循环，编译测试项目建立是否正确无误。

2、硬件映射

硬件映射的目的是按目前的硬件连接建立.h文件，如下图所示：

因此基于开发板I2C0采用的是PB6/PB7引脚，因为需要打印读出的值，UART0使用的是PA9/PA10引脚。

3、编写代码

①UART0初始化和printf函数重定向：

void UART_TypeInit(void)

{

    gpio_deinit(UART0_GPIO_PORT);

    usart_deinit(USART0);

    rcu_periph_clock_enable(UART0_GPIO_PORT_CLK);

    gpio_mode_set(UART0_GPIO_PORT,GPIO_MODE_AF,GPIO_PUPD_NONE,UART0_TX_PIN | UART0_RX_PIN);

    gpio_output_options_set(UART0_GPIO_PORT,GPIO_OTYPE_OD,GPIO_OSPEED_MAX,UART0_TX_PIN | UART0_RX_PIN);

    gpio_af_set(UART0_GPIO_PORT,GPIO_AF_1,UART0_TX_PIN | UART0_RX_PIN);

    rcu_periph_clock_enable(UART0_CLK);

    usart_baudrate_set(USART0,UART0_Baudrate);

    usart_parity_config(USART0,USART_PM_NONE);

    usart_word_length_set(USART0,USART_WL_8BIT);

    usart_stop_bit_set(USART0,USART_STB_1BIT);

    usart_enable(USART0);

    usart_transmit_config(USART0,USART_TRANSMIT_ENABLE);

    usart_receive_config(USART0,USART_RECEIVE_ENABLE);

}

/* retarget the C library printf function to the USART */

int fputc(int ch, FILE *f)

{

    usart_data_transmit(USART0, (uint8_t)ch);

    while(RESET == usart_flag_get(USART0,USART_FLAG_TBE)); 

    return ch;

}

②I2C0外设初始化：

void I2C0_TypeInit(void)

{

    gpio_deinit(I2C0_GPIO_PORT);

    i2c_deinit(I2C0);

    rcu_periph_clock_enable(I2C0_GPIO_PORT_CLK);

    gpio_mode_set(I2C0_GPIO_PORT,GPIO_MODE_AF,GPIO_PUPD_NONE,I2C0_SCL_PIN | I2C0_SDA_PIN);

    gpio_output_options_set(I2C0_GPIO_PORT,GPIO_OTYPE_OD,GPIO_OSPEED_MAX,I2C0_SCL_PIN | I2C0_SDA_PIN);

    gpio_af_set(I2C0_GPIO_PORT,GPIO_AF_1,I2C0_SCL_PIN | I2C0_SDA_PIN);

    rcu_periph_clock_enable(I2C0_CLK);

    i2c_clock_config(I2C0,I2C0_Frequence,I2C_DTCY_2);

    i2c_mode_addr_config(I2C0,I2C_I2CMODE_ENABLE,I2C_ADDFORMAT_7BITS,I2C0_OWN_Address);

    i2c_enable(I2C0);

    i2c_ack_config(I2C0,I2C_ACK_ENABLE);

}

③读寄存器操作：

void  I2C0_Register_Read(uint8_t* B_buffer, uint8_t read_address,uint16_t number_of_byte)

{

     /* wait until I2C bus is idle */

    while(i2c_flag_get(I2C0, I2C_FLAG_I2CBSY));

    if(2 == number_of_byte){

        i2c_ackpos_config(I2C0,I2C_ACKPOS_NEXT);

    }

    /* send a start condition to I2C bus */

    i2c_start_on_bus(I2C0);

    /* wait until SBSEND bit is set */

    while(!i2c_flag_get(I2C0, I2C_FLAG_SBSEND));

    /* send slave address to I2C bus */

    i2c_master_addressing(I2C0, HDC1080_Addr, I2C_TRANSMITTER);

    /* wait until ADDSEND bit is set */

    while(!i2c_flag_get(I2C0, I2C_FLAG_ADDSEND));

    /* clear the ADDSEND bit */

    i2c_flag_clear(I2C0, I2C_FLAG_ADDSEND);

    /* wait until the transmit data buffer is empty */

    while(SET != i2c_flag_get( I2C0 , I2C_FLAG_TBE));

    /* enable I2C0*/

    i2c_enable(I2C0);

    /* send the EEPROM's internal address to write to */

    i2c_data_transmit(I2C0, read_address);  

    /* wait until BTC bit is set */

    while(!i2c_flag_get(I2C0, I2C_FLAG_BTC));

        delay_1ms(20);

    /* send a start condition to I2C bus */

    i2c_start_on_bus(I2C0);

    /* wait until SBSEND bit is set */

    while(!i2c_flag_get(I2C0, I2C_FLAG_SBSEND));

    /* send slave address to I2C bus */

    i2c_master_addressing(I2C0, HDC1080_Addr, I2C_RECEIVER);

    if(number_of_byte < 3){

        /* disable acknowledge */

        i2c_ack_config(I2C0,I2C_ACK_DISABLE);

    }

    /* wait until ADDSEND bit is set */

    while(!i2c_flag_get(I2C0, I2C_FLAG_ADDSEND));

    /* clear the ADDSEND bit */

    i2c_flag_clear(I2C0,I2C_FLAG_ADDSEND);

    if(1 == number_of_byte){

        /* send a stop condition to I2C bus */

        i2c_stop_on_bus(I2C0);

    }

    /* while there is data to be read */

    while(number_of_byte){

        if(3 == number_of_byte){

            /* wait until BTC bit is set */

            while(!i2c_flag_get(I2C0, I2C_FLAG_BTC));

            /* disable acknowledge */

            i2c_ack_config(I2C0,I2C_ACK_DISABLE);

        }

        if(2 == number_of_byte){

            /* wait until BTC bit is set */

            while(!i2c_flag_get(I2C0, I2C_FLAG_BTC));

            /* send a stop condition to I2C bus */

            i2c_stop_on_bus(I2C0);

        }

                delay_1ms(1);

        /* wait until the RBNE bit is set and clear it */

        if(i2c_flag_get(I2C0, I2C_FLAG_RBNE)){

            /* read a byte from the EEPROM */

            *B_buffer = i2c_data_receive(I2C0);

            /* point to the next location where the byte read will be saved */

            B_buffer++; 

            /* decrement the read bytes counter */

            number_of_byte--;

        } 

    }

    /* wait until the stop condition is finished */

    while(I2C_CTL0(I2C0)&0x0200);

    /* enable acknowledge */

    i2c_ack_config(I2C0, I2C_ACK_ENABLE);

    i2c_ackpos_config(I2C0, I2C_ACKPOS_CURRENT);

}

④写寄存器操作：

void I2C0_Byte_Write(uint8_t* P_buffer, uint8_t write_address)

{

    uint8_t i;

    /* wait until I2C bus is idle */

    while(i2c_flag_get(I2C0, I2C_FLAG_I2CBSY));

    /* send a start condition to I2C bus */

    i2c_start_on_bus(I2C0);

    /* wait until SBSEND bit is set */

    while(!i2c_flag_get(I2C0, I2C_FLAG_SBSEND));

    /* send slave address to I2C bus */

    i2c_master_addressing(I2C0, HDC1080_Addr, I2C_TRANSMITTER);

    /* wait until ADDSEND bit is set */

    while(!i2c_flag_get(I2C0, I2C_FLAG_ADDSEND));

    /* clear the ADDSEND bit */

    i2c_flag_clear(I2C0,I2C_FLAG_ADDSEND);

    /* wait until the transmit data buffer is empty */

    while(SET != i2c_flag_get(I2C0, I2C_FLAG_TBE));

    /* send the EEPROM's internal address to write to : only one byte address */

    i2c_data_transmit(I2C0, write_address);

    /* wait until BTC bit is set */

    while(!i2c_flag_get(I2C0, I2C_FLAG_BTC));

    for(i=0;i<2;i++)

    {

        /* send the byte to be written */

        i2c_data_transmit(I2C0, *(P_buffer+i)); 

        /* wait until BTC bit is set */

        while(!i2c_flag_get(I2C0, I2C_FLAG_TBE));

    }

    /* send a stop condition to I2C bus */

    i2c_stop_on_bus(I2C0);

    /* wait until the stop condition is finished */

    while(I2C_CTL0(I2C0)&0x0200);

}

⑤对HDC1080进行初始化并读取其ID：

void HDC1080_Init(void)

{

    uint8_t    IDBuffer[2]={0};

    uint8_t InitSetup[2]={0x90,0x00};

    uint32_t SID[3]={0},MID=0,DID=0;

    I2C0_Byte_Write(InitSetup,CONFIGURATION);

    delay_1ms(20);

    I2C0_Register_Read(IDBuffer,DEVICE_ID,2);

    DID = (((uint32_t)IDBuffer[0])<<8 | IDBuffer[1]);

    printf('The DeviceID is 0x%xnr',DID);

    I2C0_Register_Read(IDBuffer,MANUFACTURE_ID,2);

    MID = ((uint16_t) IDBuffer[0]<<8 | IDBuffer[1]);

    printf('The ManufactureID is 0x%xnr',MID);

    I2C0_Register_Read(IDBuffer,FIRST_SID,2);

    SID[0] = ((uint16_t) IDBuffer[0]<<8 | IDBuffer[1]); 

    I2C0_Register_Read(IDBuffer,MID_SID,2);

    SID[1] = ((uint16_t) IDBuffer[0]<<8 | IDBuffer[1]);

    I2C0_Register_Read(IDBuffer,LAST_SID,2);

    SID[2] = ((uint16_t) IDBuffer[0]<<8 | IDBuffer[1]);

    printf('The First bytes of the serial ID of the part is 0x%xnr',SID[0]);

    printf('The MID bytes of the serial ID of the part is 0x%xnr',SID[1]);

    printf('The Last bytes of the serial ID of the part is 0x%xnr',SID[2]);

    printf('nr');

}

⑥读取温湿度值并转换成十进制显示：

void readSensor(void)

{

  //holds 2 bytes of data from I2C Line

  uint8_t Buffer_Byte[2];

  //holds the total contents of the temp register

  uint16_t temp,hum;

  //holds the total contents of the humidity register

  double temperature=0,humidity=0 ;

    I2C0_Register_Read(Buffer_Byte,T_MEASUREMENT,2);

    temp = (((uint32_t)Buffer_Byte[0])<<8 | Buffer_Byte[1]);

    temperature = (double)(temp)/(65536)*165-40;

    printf('The temperature is %.2fnr',temperature);

    I2C0_Register_Read(Buffer_Byte,RH_MEASUREMENT,2);

    hum = (((uint32_t)Buffer_Byte[0])<<8 | Buffer_Byte[1]);

    humidity = (double)(hum)/(65536)*100;

    printf('The humidity is %.2f%%nr',humidity);    

}

⑦main函数：

/*!

    brief      main function

    param[in]  none

    param[out] none

    retval     none

*/

int main(void)

{

    /* configure periphreal */

  systick_Init();

    LED_TypeInit();

//    NVIC_config();

//    KEY_EXTI_TypeInit();

    UART_TypeInit();

    I2C0_TypeInit();

    printf('**********DEMO START**********nr');

    printf('******************************nr');

    HDC1080_Init();

    while(1) 

    {

        readSensor();

        delay_1ms(1000);

    }

}

4、编译下载

①Build项目文件：

②没有错误，直接下载到开发板中，可以打开串口看到读出温湿度每隔1S读一次并打印出来，与环境温度计比较取值还是比较准确的。

5、试用总结

GD32F310G8芯片采用4x4 QFN28封装，结构可以设计相当紧凑，软件开发资源也是很丰富，虽然功能不算特别强大，但主流的外设基本都有囊括，在目前国产替代的大环境之下，应用前景还是相当广泛的。