为啥我的ntc检测温度ad值不对应 -

/*---------------------------------------------------------------------*/
/* --- STC MCU Limited ------------------------------------------------*/
/* --- STC 1T Series MCU Demo Programme -------------------------------*/
/* 如果要在程序中使用此代码,请在程序中注明使用了STC的资料及程序 */
/*---------------------------------------------------------------------*/
/************* 本程序功能说明 **************
本例程基于STC8H8K64U为主控芯片的实验箱9进行编写测试，STC8G、STC8H系列芯片可通用参考.
读ADC和测温度.
用STC的MCU的IO方式驱动8位数码管。
使用Timer0的16位自动重装来产生1ms节拍,程序运行于这个节拍下,用户修改MCU主时钟频率时,自动定时于1ms.
右边4位数码管显示温度值, 分辨率0.1度.
NTC使用1%精度的MF52 10K@25度.
测温度时, 使用12位的ADC值, 使用对分查找表格来计算, 小数点后一位数是用线性插补来计算的.
下载时, 选择时钟 24MHZ (用户可自行修改频率).
******************************************/
#include "reg51.h" //包含此头文件后，里面声明的寄存器不需要再手动输入，避免重复定义
#include "intrins.h"
#define MAIN_Fosc 24000000L //定义主时钟
typedef unsigned char u8;
typedef unsigned int u16;
typedef unsigned long u32;
//手动输入声明"reg51.h"头文件里面没有定义的寄存器
sfr TH2 = 0xD6;
sfr TL2 = 0xD7;
sfr IE2 = 0xAF;
sfr INT_CLKO = 0x8F;
sfr AUXR = 0x8E;
sfr AUXR1 = 0xA2;
sfr P_SW1 = 0xA2;
sfr P_SW2 = 0xBA;
sfr S2CON = 0x9A;
sfr S2BUF = 0x9B;
sfr ADC_CONTR = 0xBC; //带AD系列
sfr ADC_RES = 0xBD; //带AD系列
sfr ADC_RESL = 0xBE; //带AD系列
sfr ADCCFG = 0xde;
sfr P4 = 0xC0;
sfr P5 = 0xC8;
sfr P6 = 0xE8;
sfr P7 = 0xF8;
sfr P1M1 = 0x91; //PxM1.n,PxM0.n =00--->Standard, 01--->push-pull
sfr P1M0 = 0x92; // =10--->pure input, 11--->open drain
sfr P0M1 = 0x93;
sfr P0M0 = 0x94;
sfr P2M1 = 0x95;
sfr P2M0 = 0x96;
sfr P3M1 = 0xB1;
sfr P3M0 = 0xB2;
sfr P4M1 = 0xB3;
sfr P4M0 = 0xB4;
sfr P5M1 = 0xC9;
sfr P5M0 = 0xCA;
sfr P6M1 = 0xCB;
sfr P6M0 = 0xCC;
sfr P7M1 = 0xE1;
sfr P7M0 = 0xE2;
sbit P00 = P0^0;
sbit P01 = P0^1;
sbit P02 = P0^2;
sbit P03 = P0^3;
sbit P04 = P0^4;
sbit P05 = P0^5;
sbit P06 = P0^6;
sbit P07 = P0^7;
sbit P10 = P1^0;
sbit P11 = P1^1;
sbit P12 = P1^2;
sbit P13 = P1^3;
sbit P14 = P1^4;
sbit P15 = P1^5;
sbit P16 = P1^6;
sbit P17 = P1^7;
sbit P20 = P2^0;
sbit P21 = P2^1;
sbit P22 = P2^2;
sbit P23 = P2^3;
sbit P24 = P2^4;
sbit P25 = P2^5;
sbit P26 = P2^6;
sbit P27 = P2^7;
sbit P30 = P3^0;
sbit P31 = P3^1;
sbit P32 = P3^2;
sbit P33 = P3^3;
sbit P34 = P3^4;
sbit P35 = P3^5;
sbit P36 = P3^6;
sbit P37 = P3^7;
sbit P40 = P4^0;
sbit P41 = P4^1;
sbit P42 = P4^2;
sbit P43 = P4^3;
sbit P44 = P4^4;
sbit P45 = P4^5;
sbit P46 = P4^6;
sbit P47 = P4^7;
sbit P50 = P5^0;
sbit P51 = P5^1;
sbit P52 = P5^2;
sbit P53 = P5^3;
sbit P54 = P5^4;
sbit P55 = P5^5;
sbit P56 = P5^6;
sbit P57 = P5^7;
/****************************** 用户定义宏 ***********************************/
#define ADCTIM (*(unsigned char volatile xdata *)0xfea8)
#define Timer0_Reload (65536UL -(MAIN_Fosc / 1000)) //Timer 0 中断频率, 1000次/秒
/*****************************************************************************/
#define DIS_DOT 0x20
#define DIS_BLACK 0x10
#define DIS_ 0x11
/************* 本地常量声明 **************/
u8 code t_display[]={ //标准字库
// 0 1 2 3 4 5 6 7 8 9 A B C D E F
0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,0x7F,0x6F,0x77,0x7C,0x39,0x5E,0x79,0x71,
//black - H J K L N o P U t G Q r M y
0x00,0x40,0x76,0x1E,0x70,0x38,0x37,0x5C,0x73,0x3E,0x78,0x3d,0x67,0x50,0x37,0x6e,
0xBF,0x86,0xDB,0xCF,0xE6,0xED,0xFD,0x87,0xFF,0xEF,0x46}; //0. 1. 2. 3. 4. 5. 6. 7. 8. 9. -1
u8 code T_COM[]={0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80}; //位码
/************* 本地变量声明 **************/
u8 LED8[8]; //显示缓冲
u8 display_index; //显示位索引
bit B_1ms; //1ms标志
u16 msecond;
/************* 本地函数声明 **************/
u16 get_temperature(u16 adc);
u16 Get_ADC12bitResult(u8 channel); //channel = 0~15
/**********************************************/
void main(void)
{
u8 i;
u16 j;
P0M1 = 0x00; P0M0 = 0x00; //设置为准双向口
P2M1 = 0x00; P2M0 = 0x00; //设置为准双向口
P3M1 = 0x00; P3M0 = 0x00; //设置为准双向口
P4M1 = 0x00; P4M0 = 0x00; //设置为准双向口
P5M1 = 0x00; P5M0 = 0x00; //设置为准双向口
P6M1 = 0x00; P6M0 = 0x00; //设置为准双向口
P7M1 = 0x00; P7M0 = 0x00; //设置为准双向口
P1M1 = 0x08; P1M0 = 0x00; //设置 P1.3 为 ADC 输入口
display_index = 0;
P_SW2 |= 0x80;
ADCTIM = 0x3f; //设置 ADC 内部时序，ADC采样时间建议设最大值
P_SW2 &= 0x7f;
ADCCFG = 0x2f; //设置 ADC 时钟为系统时钟/2/16/16
ADC_CONTR = 0x80; //使能 ADC 模块
AUXR = 0x80; //Timer0 set as 1T, 16 bits timer auto-reload,
TH0 = (u8)(Timer0_Reload / 256);
TL0 = (u8)(Timer0_Reload % 256);
ET0 = 1; //Timer0 interrupt enable
TR0 = 1; //Tiner0 run
EA = 1; //打开总中断
for(i=0; i<8; i++) LED8[i] = 0x10; //上电消隐
while(1)
{
if(B_1ms) //1ms到
{
B_1ms = 0;
if(++msecond >= 300) //300ms到
{
msecond = 0;
j = Get_ADC12bitResult(3); //参数0~15,查询方式做一次ADC, 返回值就是结果, == 4096 为错误
if(j < 4096)
{
/*
LED8[0] = j / 1000; //显示ADC值
LED8[1] = (j % 1000) / 100;
LED8[2] = (j % 100) / 10;
LED8[3] = j % 10;
if(LED8[0] == 0) LED8[0] = DIS_BLACK;
*/
j = get_temperature(j); //计算温度值
if(j >= 400) F0 = 0, j -= 400; //温度 >= 0度
else F0 = 1, j = 400 - j; //温度 < 0度
LED8[4] = j / 1000; //显示温度值
LED8[5] = (j % 1000) / 100;
LED8[6] = (j % 100) / 10 + DIS_DOT;
LED8[7] = j % 10;
if(LED8[4] == 0) LED8[4] = DIS_BLACK;
if(F0) LED8[4] = DIS_; //显示-
}
else //错误
{
for(i=0; i<8; i++) LED8[i] = DIS_;
}
}
}
}
}
/**********************************************/
//========================================================================
// 函数: u16 Get_ADC12bitResult(u8 channel)
// 描述: 查询法读一次ADC结果.
// 参数: channel: 选择要转换的ADC.
// 返回: 12位ADC结果.
// 版本: V1.0, 2012-10-22
//========================================================================
u16 Get_ADC12bitResult(u8 channel) //channel = 0~15
{
ADC_RES = 0;
ADC_RESL = 0;
ADC_CONTR = (ADC_CONTR & 0xF0) | 0x40 | channel; //启动 AD 转换
_nop_();
_nop_();
_nop_();
_nop_();
while((ADC_CONTR & 0x20) == 0) ; //wait for ADC finish
ADC_CONTR &= ~0x20; //清除ADC结束标志
return (((u16)ADC_RES << 8) | ADC_RESL);
}
// MF52E 10K at 25, B = 3950, ADC = 12 bits
u16 code temp_table[]={
140, //;-40 0
149, //;-39 1
159, //;-38 2
168, //;-37 3
178, //;-36 4
188, //;-35 5
199, //;-34 6
210, //;-33 7
222, //;-32 8
233, //;-31 9
246, //;-30 10
259, //;-29 11
272, //;-28 12
286, //;-27 13
301, //;-26 14
317, //;-25 15
333, //;-24 16
349, //;-23 17
367, //;-22 18
385, //;-21 19
403, //;-20 20
423, //;-19 21
443, //;-18 22
464, //;-17 23
486, //;-16 24
509, //;-15 25
533, //;-14 26
558, //;-13 27
583, //;-12 28
610, //;-11 29
638, //;-10 30
667, //;-9 31
696, //;-8 32
727, //;-7 33
758, //;-6 34
791, //;-5 35
824, //;-4 36
858, //;-3 37
893, //;-2 38
929, //;-1 39
965, //;0 40
1003, //;1 41
1041, //;2 42
1080, //;3 43
1119, //;4 44
1160, //;5 45
1201, //;6 46
1243, //;7 47
1285, //;8 48
1328, //;9 49
1371, //;10 50
1414, //;11 51
1459, //;12 52
1503, //;13 53
1548, //;14 54
1593, //;15 55
1638, //;16 56
1684, //;17 57
1730, //;18 58
1775, //;19 59
1821, //;20 60
1867, //;21 61
1912, //;22 62
1958, //;23 63
2003, //;24 64
2048, //;25 65
2093, //;26 66
2137, //;27 67
2182, //;28 68
2225, //;29 69
2269, //;30 70
2312, //;31 71
2354, //;32 72
2397, //;33 73
2438, //;34 74
2479, //;35 75
2519, //;36 76
2559, //;37 77
2598, //;38 78
2637, //;39 79
2675, //;40 80
2712, //;41 81
2748, //;42 82
2784, //;43 83
2819, //;44 84
2853, //;45 85
2887, //;46 86
2920, //;47 87
2952, //;48 88
2984, //;49 89
3014, //;50 90
3044, //;51 91
3073, //;52 92
3102, //;53 93
3130, //;54 94
3157, //;55 95
3183, //;56 96
3209, //;57 97
3234, //;58 98
3259, //;59 99
3283, //;60 100
3306, //;61 101
3328, //;62 102
3351, //;63 103
3372, //;64 104
3393, //;65 105
3413, //;66 106
3432, //;67 107
3452, //;68 108
3470, //;69 109
3488, //;70 110
3506, //;71 111
3523, //;72 112
3539, //;73 113
3555, //;74 114
3571, //;75 115
3586, //;76 116
3601, //;77 117
3615, //;78 118
3628, //;79 119
3642, //;80 120
3655, //;81 121
3667, //;82 122
3679, //;83 123
3691, //;84 124
3702, //;85 125
3714, //;86 126
3724, //;87 127
3735, //;88 128
3745, //;89 129
3754, //;90 130
3764, //;91 131
3773, //;92 132
3782, //;93 133
3791, //;94 134
3799, //;95 135
3807, //;96 136
3815, //;97 137
3822, //;98 138
3830, //;99 139
3837, //;100 140
3844, //;101 141
3850, //;102 142
3857, //;103 143
3863, //;104 144
3869, //;105 145
3875, //;106 146
3881, //;107 147
3887, //;108 148
3892, //;109 149
3897, //;110 150
3902, //;111 151
3907, //;112 152
3912, //;113 153
3917, //;114 154
3921, //;115 155
3926, //;116 156
3930, //;117 157
3934, //;118 158
3938, //;119 159
3942 //;120 160
};
/******************** 计算温度 ***********************************************/
// 计算结果: 0对应-40.0度, 400对应0度, 625对应25.0度, 最大1600对应120.0度.
// 为了通用, ADC输入为12bit的ADC值.
// 电路和软件算法设计: Coody
/**********************************************/
#define D_SCALE 10 //结果放大倍数, 放大10倍就是保留一位小数
u16 get_temperature(u16 adc)
{
u16 code *p;
u16 i;
u8 j,k,min,max;
adc = 4096 - adc; //Rt接地
p = temp_table;
if(adc < p[0]) return (0xfffe);
if(adc > p[160]) return (0xffff);
min = 0; //-40度
max = 160; //120度
for(j=0; j<5; j++) //对分查表
{
k = min / 2 + max / 2;
if(adc <= p[k]) max = k;
else min = k;
}
if(adc == p[min]) i = min * D_SCALE;
else if(adc == p[max]) i = max * D_SCALE;
else // min < temp < max
{
while(min <= max)
{
min++;
if(adc == p[min]) {i = min * D_SCALE; break;}
else if(adc < p[min])
{
min--;
i = p[min]; //min
j = (adc - i) * D_SCALE / (p[min+1] - i);
i = min;
i *= D_SCALE;
i += j;
break;
}
}
}
return i;
}
/********************** 显示扫描函数 ************************/
void DisplayScan(void)
{
P7 = ~T_COM[7-display_index];
P6 = ~t_display[LED8[display_index]];
if(++display_index >= 8) display_index = 0; //8位结束回0
}
/********************** Timer0 1ms中断函数 ************************/
void timer0 (void) interrupt 1
{
DisplayScan(); //1ms扫描显示一位
B_1ms = 1; //1ms标志
}

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