使用背景

首先感謝華大半導體產商的辛苦努力 ，發布了一款高性價比的MCU-HC32F460 系列，它是基于 ARM Cortex-M4 32-bit RISC CPU，最高作業頻率200MHz 的高性能 MCU，Cortex-M4 內核集成了浮點運算單元FPU和 DSP，實作單精度浮點算術運算，支持所有 ARM 單精度資料處理指令和資料型別，支持完整 DSP 指令集，

使用用途

場景

測量高溫加熱模塊的溫度

熱電偶其特點主要如下：

1、裝配簡單，更換方便；
2、壓簧式感溫元件，抗震性能好；
3、測量精度高；
4、測量范圍大（－200℃～1300℃，特殊情況下－270℃～2800℃）,目前我使用的最高只能到600°；
5、熱回應時間快；

具體代碼實作

#include "hc32f46x.h"
#include "bsp_spi.h"
#include "hc32f46x_spi.h"
#include "hc32_ddl.h"

/* SPI_SCK Port/Pin definition */
#define SPI_SCK_PORT                    (PortB)
#define SPI_SCK_PIN                     (Pin13)
#define SPI_SCK_FUNC                    (Func_Spi3_Sck)

/* SPI_NSS Port/Pin definition */
#define SPI_NSS_PORT                    (PortB)
#define SPI_NSS_PIN                     (Pin12)
#define SPI_NSS_HIGH()                  (PORT_SetBits(SPI_NSS_PORT, SPI_NSS_PIN))
#define SPI_NSS_LOW()                   (PORT_ResetBits(SPI_NSS_PORT, SPI_NSS_PIN))

/* SPI_MOSI Port/Pin definition */
#define SPI_MOSI_PORT                   (PortE)
#define SPI_MOSI_PIN                    (Pin15)
#define SPI_MOSI_FUNC                   (Func_Spi3_Mosi)

/* SPI_MISO Port/Pin definition */
#define SPI_MISO_PORT                   (PortB)
#define SPI_MISO_PIN                    (Pin14)
#define SPI_MISO_FUNC                   (Func_Spi3_Miso)

#define SPI_UNIT                        (M4_SPI3)
#define SPI_UNIT_CLOCK                  (PWC_FCG1_PERIPH_SPI3)


static void Spi_Config(void)
{
    stc_spi_init_t stcSpiInit;

    /* configuration structure initialization */
    MEM_ZERO_STRUCT(stcSpiInit);

    /* Configuration peripheral clock */
    PWC_Fcg1PeriphClockCmd(SPI_UNIT_CLOCK, Enable);

    /* Configuration SPI pin */
    PORT_SetFunc(SPI_SCK_PORT, SPI_SCK_PIN, SPI_SCK_FUNC, Disable);
    PORT_SetFunc(SPI_MOSI_PORT, SPI_MOSI_PIN, SPI_MOSI_FUNC, Disable);
    PORT_SetFunc(SPI_MISO_PORT, SPI_MISO_PIN, SPI_MISO_FUNC, Disable);

    /* Configuration SPI structure */
    stcSpiInit.enClkDiv = SpiClkDiv256;
    stcSpiInit.enFrameNumber = SpiFrameNumber1;
    stcSpiInit.enDataLength = SpiDataLengthBit8;
    stcSpiInit.enFirstBitPosition = SpiFirstBitPositionMSB;
    stcSpiInit.enSckPolarity = SpiSckIdleLevelLow;
    stcSpiInit.enSckPhase = SpiSckOddSampleEvenChange;
    stcSpiInit.enReadBufferObject = SpiReadReceiverBuffer;
    stcSpiInit.enWorkMode = SpiWorkMode4Line;
    stcSpiInit.enTransMode = SpiTransFullDuplex;
    stcSpiInit.enCommAutoSuspendEn = Disable;
    stcSpiInit.enModeFaultErrorDetectEn = Disable;
    stcSpiInit.enParitySelfDetectEn = Disable;
    stcSpiInit.enParityEn = Disable;
    stcSpiInit.enParity = SpiParityEven;
    stcSpiInit.enMasterSlaveMode = SpiModeMaster;
    stcSpiInit.stcDelayConfig.enSsSetupDelayOption = SpiSsSetupDelayCustomValue;
    stcSpiInit.stcDelayConfig.enSsSetupDelayTime = SpiSsSetupDelaySck1;
    stcSpiInit.stcDelayConfig.enSsHoldDelayOption = SpiSsHoldDelayCustomValue;
    stcSpiInit.stcDelayConfig.enSsHoldDelayTime = SpiSsHoldDelaySck1;
    stcSpiInit.stcDelayConfig.enSsIntervalTimeOption = SpiSsIntervalCustomValue;
    stcSpiInit.stcDelayConfig.enSsIntervalTime = SpiSsIntervalSck6PlusPck2;

    SPI_Init(SPI_UNIT, &stcSpiInit);
    SPI_Cmd(SPI_UNIT, Enable);
}

/*
*  Init hoten0 Configure
*/
void spi_init(void)
{
    stc_port_init_t stcPortInit;
    /* configure structure initialization */
    MEM_ZERO_STRUCT(stcPortInit);
    /* Flash NSS */
    stcPortInit.enPinMode = Pin_Mode_Out;
    PORT_Init(SPI_NSS_PORT, SPI_NSS_PIN, &stcPortInit);
    SPI_NSS_HIGH();
	  Spi_Config();
}

/**
 *******************************************************************************
 ** \brief SPI flash write byte function
 **
 ** \param [in] u8Data                      SPI write data to flash
 **
 ** \retval uint8_t                         SPI receive data from flash
 **
 ******************************************************************************/
static uint8_t SpiFlash_WriteReadByte(uint8_t u8Data)
{
    uint8_t u8Byte;

    /* Wait tx buffer empty */
    while (Reset == SPI_GetFlag(SPI_UNIT, SpiFlagSendBufferEmpty))
    {
    }
    /* Send data */
    SPI_SendData8(SPI_UNIT, u8Data);
    /* Wait rx buffer full */
    while (Reset == SPI_GetFlag(SPI_UNIT, SpiFlagReceiveBufferFull))
    {
    }
    /* Receive data */
    u8Byte = SPI_ReceiveData8(SPI_UNIT);

    return u8Byte;
}

/*
*  Read hoten0 temperature value
*/
float SpiTemp_Read(void)
{
		int data = 0xff;
	  uint16_t adValue = 0;
		float temperature = 0.0;
	
    SPI_NSS_LOW();
    adValue = SpiFlash_WriteReadByte(data);
    while (Reset == SPI_GetFlag(SPI_UNIT, SpiFlagSpiIdle))
    {
    }
				
		adValue = adValue<<8 | SpiFlash_WriteReadByte(data);			
		if (adValue & 0X04) 
		{
				adValue = 0;  //未檢測到熱電偶
		}
		else 
		{
				adValue<<=1;  //去掉D15位
				adValue>>=4;	//去掉D0、1、2位
		}
		temperature = adValue*1023.75/4095;			
    SPI_NSS_HIGH();
		
		return temperature;
}