度的数字电压值，则继续取出下一温度的数字电压进行比较
DEC R2; 小于当前温度的数字电压值，则查表取出前一个温度值作为当前温度值 DEC R2 DEC R2 MOV A,R2;
MOVC A,@A+DPTR; LJMP K3; K2:INC R2; INC R2;
LJMP NEXT1;
K3:MOV 21H,A; 将当前温度值存于21H单元 RET;
DATATAB;DB
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0,194,1,193,2,192,3,191,4,190；温度数据表
DB
5,189,6,188,7,187,8,186,9,185 DB
10,184,11,182,12,181,13,180,14,178 DB
15,177,16,175,17,174,18,173,19,171 DB
20,169,21,168,22,166,23,165,24,163 DB
25,161,26,159,27,158,28,156,29,154 DB
30,152,31,150,32,149,33,147,34,145 DB
35,143,36,141,37,139,38,137,39,135 DB
40,133,41,131,42,129,43,127,44,125 DB
45,123,46,121,47,118,48,116,49,114
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驱动控制子程序 ORG 0500H;
DRVCON:MOV A,21H; 取出当前温度值
CJNE A,#30,J1; 与上限温度值（30℃）比较 LJMP GO;
J1:JNC DRV1; 若高于上限温度，则输出驱动信号，同时高于上限温度指示灯点亮
CJNE A,#25,J2; 与显现温度（25℃）比较 LJMP GO;
J2:JC DRV2; 弱低于下限温度，则驱动信号停止输出，同时点亮低于下限温度的指示灯
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LJMP GO;
DRV1:CLR P1.0; SETB P1.1; CLR P1.2; SETB P1.3; LJMP OVER; DRV2:SETB P1.0 SETB P1.1; CLR P1.2; SETB P1.3; LJMP OVER; DRV2:SETB P1.0; SETB P1.1; SETB P1.1; SETB P1.2; CLR P1.3; LJMP OVER;
GO:CLR P1.1; 在下线温度（25℃）至上限温度（30℃）之间，则驱动信号保持前面状态，同时温度
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