NTC 负温度系数 10倍显示

typedef unsigned short uint16_t;
typedef short int16_t;

//注意0度时的AD
#define MULTI_MIN_DEGREE (-4*10)
#define MULTI_MAX_DEGREE (5*10)
#define MULTI_ZERO_DEGREE_INDEX 4
#define MULTI_MAX_LENGTH  10


const uint16_t NTC_3950_MUTI_TEN[MULTI_MAX_LENGTH]={
	354,//-4度的中间ad
	331,//-3度的中间ad
	310,//-2度的中间ad
	290,//-1度的中间ad
	271,//0    中间ad
	254,//1度的中间ad
	238,//2度的中间ad
	223,//3度的中间ad
	180,//4度的中间ad
	170,//5度的中间ad
};

/*
 *@brief temprature_transfer: 将输入的AD值转换成温度
 *@param adcVal：输入的AD值
 *@retval 返回温度值
 */
int16_t temprature_transfer_multi_10(uint16_t adcVal)
{
	int16_t res = 0;
	int16_t offset = 0;
	int16_t t = 0;

	uint16_t left = 0;
	uint16_t right = MULTI_MAX_LENGTH-1;
	uint16_t mid = 0;

	if(adcVal >= NTC_3950_MUTI_TEN[0])return MULTI_MIN_DEGREE;
	if(adcVal <= NTC_3950_MUTI_TEN[MULTI_MAX_LENGTH-1])return MULTI_MAX_DEGREE;

	while(left <= right)
	{
		mid = (left+right)>>1;

		if(NTC_3950_MUTI_TEN[mid] <= adcVal)
		{
			res = mid;
			right = mid-1;
		}
		else
		{
			left = mid+1;
		}
	}

	if(res <= MULTI_ZERO_DEGREE_INDEX)
	{
		if(res != 0)
		{
			if(NTC_3950_MUTI_TEN[res-1] != NTC_3950_MUTI_TEN[res])
			{
				offset = (adcVal - NTC_3950_MUTI_TEN[res])*10/(NTC_3950_MUTI_TEN[res-1]-NTC_3950_MUTI_TEN[res]);
			}
		}
		res -= MULTI_ZERO_DEGREE_INDEX;
		res *= 10;
		res -= offset;
	}
	else
	{
		if(res < MULTI_MAX_LENGTH)
		{
			if(NTC_3950_MUTI_TEN[res-1] != NTC_3950_MUTI_TEN[res])
			{
				offset = (NTC_3950_MUTI_TEN[res-1] - adcVal)*10/(NTC_3950_MUTI_TEN[res-1]-NTC_3950_MUTI_TEN[res]);
			}
		}
		res -= (MULTI_ZERO_DEGREE_INDEX+1);
		res *= 10;
		res += offset;
	}

	return res;
}