#include "STM32Lib\\stm32f10x.h"
#include "ads1220.h"

//SPI读写函数
u8 ads1220_SendByte(u8 byte)
{
    while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);
    SPI_I2S_SendData(SPI1, byte);
    while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET);
    return SPI_I2S_ReceiveData(SPI1);
}

//芯片复位初始化
void ads1220_Initialization (void)
{
    u32 data_temp;

    for (data_temp = 0; data_temp < 72000 * 50; data_temp++) {;}

    AD_CS_H;
    AD_CS_L;
    AD_CS_L;
    AD_CS_L;
    ads1220_SendByte (ADS1220_COMMAND_RESET);							//复位
    for (data_temp = 0; data_temp < 72000 * 50; data_temp++) {;}
    AD_CS_L;
    AD_CS_L;
    AD_CS_L;
    AD_CS_H;

    for (data_temp = 0; data_temp < 72000 * 5; data_temp++) {;}
    AD_CS_H;
    AD_CS_L;
    AD_CS_L;
    AD_CS_L;
    ads1220_SendByte (0x43);
    ads1220_SendByte (0x5a);//5a
    ads1220_SendByte (0x00);//
    ads1220_SendByte (0x20);//20
    ads1220_SendByte (0x00);
    AD_CS_L;
    AD_CS_L;
    AD_CS_L;
    AD_CS_H;

    for (data_temp = 0; data_temp < 72000 * 5; data_temp++) {;}
    AD_CS_H;
    AD_CS_L;
    AD_CS_L;
    AD_CS_L;
    ads1220_SendByte (0x44);
    ads1220_SendByte (0x04);	//continual exchange
    ads1220_SendByte (ADS1220_COMMAND_START);
    AD_CS_L;
    AD_CS_L;
    AD_CS_L;
    AD_CS_H;
}

//读取转换结果
u32 ads1220_read_data (void)
{
    u32 data_temp = 0;

    AD_CS_H;
    AD_CS_L;
    AD_CS_L;
    AD_CS_L;
    ads1220_SendByte (ADS1220_COMMAND_RDATA);						//读取数据寄存器

    data_temp += ads1220_SendByte (0xff);
    data_temp <<= 8;
    data_temp += ads1220_SendByte (0xff);
    data_temp <<= 8;
    data_temp += ads1220_SendByte (0xff);
    data_temp &= 0xffffff;

    if (data_temp < 0x800000)
        data_temp += 0x800000;
    else
    {
        data_temp--;
        data_temp = ~data_temp;
        data_temp &= 0xffffff;
        data_temp = 0x800000 - data_temp;
    }

    //ads1220_SendByte (ADS1220_COMMAND_START);

    AD_CS_L;
    AD_CS_L;
    AD_CS_L;
    AD_CS_H;

    return data_temp;
    //return 0x800000;
}