7.1.7浮点取整函数.txt

MCS－51单片机应用开发实用子程序.rar

FLTINT: 
LCALL 	MVR0 				
INT:	
MOV	A,R3					
ORL		A,R4
JNZ		INTA
CLR		1FH
MOV	R2,#41H
RET
INTA:	
MOV	A,R2
JZ		INTB					
JB		ACC.7,INTB			
CLR		C
SUBB	A,#10H				
JC		INTD
RET							
INTB:	
CLR		A	  				
MOV	R4,A
MOV	C,1FH
RRC		A
MOV	R3,A
RL		A
MOV	R2,A
JNZ		INTC
MOV	R2,#41H
INTC:	
RET
INTD:	
CLR		F0					
MOV0:						
INC		R0
INC		R0
MOV	A,R4
MOV	@R0,A
DEC		R0					
MOV	A,R3
MOV	@R0,A
DEC		R0
MOV	A,R2
MOV	C,1FH
MOV	ACC.7,C
MOV	@R0,A
CLR		ACC.7				
CLR		OV				
CJNE	A,#3FH,MV01
SETB	OV
MV01:	
MOV	A,@R0
INT: 
MOV 	A,R3
ORL 	A,R4
JNZ 		INTA
CLR 	1FH 					
MOV 	R2,#41H
RET 
INTA: 
MOV 	A,R2
JZ 		INTB 				
JB 		ACC.7,INTB			
CLR 	C
SUBB 	A,#10H 				
JC 		INTD
RET 						
INTB: 
CLR 	A					
MOV 	R4,A
MOV 	C,1FH
RRC 	A
MOV 	R3,A
RL 		A
MOV 	R2,A
JNZ 		INTC
MOV 	R2,#41H
INTC: 
RET
INTD: 
CLR 	F0 					
INTE:
CLR 	C
MOV	A,R3					
RRC		A
MOV	R3,A
MOV	A,R4
RRC		A
MOV	R4,A
INC		R2
CLR		OV
CJNE	R2,#40H,RR1E
MOV	R2,#3FH
SETB	OV
RR1E:	
ORL 	C,F0					
MOV	F0,C
CJNE 	R2,#10H,INTE			
JNB 		F0,INTF 				
JNB 		1FH,INTF				
INC 		R4 					
MOV 	A,R4
JNZ 		INTF
INC 		R3
INTF: 
RLNORM:	
MOV	A,R3					
ORL		A,R4					
JNZ		RLNORM1
MOV	R2,#0C1H				
RET     	
RLNORM1:	
MOV	A,R3
JB		ACC.7,RLNORM2			
CLR		C					
LCALL	RL1
SJMP	RLNORM					
RLNORM2:	
CLR		OV					
RET
RL1:	
MOV	A,R4					
RLC		A					
MOV	R4,A
MOV	A,R3
RLC		A
MOV	R3,A
DEC		R2					
CJNE	R2,#0C0H, MVR0		
CLR		A 
MOV	R3,A					
MOV	R4,A
MOV	R2,#0C1H
MVR0:	
MOV	A,@R0
MOV	C,ACC.7
MOV	1FH,C
MOV	C,ACC.6
MOV	ACC.7,C
MOV	R2,A
INC		R0					
MOV	A,@R0
MOV	R3,A
INC		R0
MOV	A,@R0
MOV	R4,A
DEC		R0					
DEC		R0					
RET