:
1. − RS −
2. :
) .
) : , , .
WAIT_L: IN IPORT
ANI 0000 0010B
JNZ WAIT_L; , D1 = 1
CALL DELAY; t
RET
:
1]
VKL: MVI A, 01H
OUT OPORT; D0 = 1
OTKL: MVI A, 00H
OUT OPORT; D0 = 0
OTKL: XRA A; ()
OUT OPORT; D0 = 0
2]
XRA A
OUT OPORT; D1 = 0
MVI A, 02H
OUT OPORT; D1 = 1
CALL DELAY; t
XRA A
OUT OPORT; D1 = 0
CALL DELAY;
DELAY: MVI B, X;
LOOP: DCR B;
JNZ LOOP; , ()=0
RET; , ()=0
, - . , MVI B, X RET , DCR B JNZ LOOP , .
:
CALL DELAY - 17
MVI B, X - 7
DCR - 5
JNZ LOOP - 10
R - 10
: t = n *T,
n - ;
- .
f :
=1/f
:
X=(t-to)/t,
t - ;
t - , ;
t - , .
. , 10 P1.7 . fCLK = 12 . T/C0 1. , :
65536 10000 = 55536 = D8F0H.
:
ORG 0000H
TIMER_1: MOV TMOD, #01H; 1 T/C0
MOV TH0, #0D8H;
MOV TL0, #0F0H;
CLR P1.7; P1.7 
0
SETB TR0;
COUNT: JNB TF0, COUNT;
; 393
SETB P1.7; P1.7 1
CLR TR0;
|
|
|
STOP: JMP STOP;
END
P1.7 2 . , 50 . 2 40 . 50 65536 50000 = 15536 = 03B0H.
:
ORG 0000H
TIMER_2: MOV TMOD, #01H; 1 T/C0
MOV R7, #40;
;
CLR P1.7; P1.7 0
AGAIN: MOV TH0, #03H;
MOV TL0, #0B0H;
SETB TR0;
COUNT: JNB TF0, COUNT;
;
CLR TR0;
CLR TF0;
;
DJNZ R7, AGAIN; 40
SETB P1.7; P1.7 1
STOP: JMP STOP;
END
: . , . () , , . () .
.
( ) , , .
:
:
:
, . 0, .
, .
:
1.
2.
.
, : . :
IN IPORT
CMA
CPI MASK
JZ EXIT
