jakey0225 发布于 2007-10-24 15:26:00
我用IO口检测12路光电开关引起的脉冲信号并记数，脉冲频率不超过1K，12路分别接P0，P2.0-P2.3 （单片机时钟为11.0592M）
程序如下：
CHECK: MOV A,P0
XRL A,P0
JNZ ADD1
CHECK1: MOV A,P2
XRL A,P2
JNZ ADD2
LJMP CHECK
ADD1，ADD2为判断那一路变化并记数
请指教这样行吗？
MOV和 XRL指令之间还须延时吗？
还是用其他的办法？
5880527 发布于 2007-10-25 19:30:00
MOV A,P0 XRL A,P0有漏洞，而且无法判断沿变化，写一段，仅供参考
用的大循环扫描，也可以用定时器扫描，只要扫描频率有个两三K就可以了
X0 EQU P0.0
X1 EQU P0.1
X0BIT0 BIT 000H
X1BIT0 BIT 001H
X0BIT BIT 010H
X1BIT BIT 011H
X0BITL BIT 020H
X1BITL BIT 021H
NUM0H EQU 030H
NUM0L EQU 031H
NUM1H EQU 032H
NUM1L EQU 033H
ORG 0000H
LJMP MAIN
ORG 30H
MAIN: MOV SP,#080H
MOV R0,#030H
WQR: MOV @R0,#00H
INC R0
MOV A,R0
CJNE A,#080H,WQR
NOP
SETB X0BIT
SETB X1BIT
SETB X0BITL
SETB X1BITL
NOP
LOOP: NOP
NOP
MOV C,X0
JC JR00
JNB X0BIT0,JR01
AJMP JR02
JR00: JB X0BIT0,JR01
AJMP JR02
JR01: MOV X0BIT,C ;检测到两次一样则认为信号稳定
JR02: MOV X0BIT0,C ;保存本次扫描到的状态
MOV C,X1
JC JR10
JNB X1BIT0,JR11
AJMP JR12
JR10: JB X1BIT0,JR11
AJMP JR12
JR11: MOV X1BIT,C ;检测到两次一样则认为信号稳定
JR12: MOV X1BIT0,C ;保存本次扫描到的状态
JB X0BIT,LEW1 ;仅下降沿计一次
JNB X0BITL,LEW1
MOV A,NUM0L
ADD A,#001H
MOV NUM0L,A
MOV A,NUM0H
ADDC A,#000H
MOV NUM0H,A ;此处未考虑溢出
LEW1: JB X1BIT,LEW2 ;仅下降沿计一次
JNB X1BITL,LEW2
MOV A,NUM1L
ADD A,#001H
MOV NUM1L,A
MOV A,NUM1H
ADDC A,#000H
MOV NUM1H,A ;此处未考虑溢出
LEW2:
MOV C,X0BIT
MOV X0BITL,C
MOV C,X1BIT
MOV X1BITL,C ;保存本次状态
LJMP LOOP
END
* - 本贴最后修改时间：2007-10-25 19:36:07 修改者：5880527
沈老 发布于 2007-10-25 19:42:00
;Main points:
;1.The width of any pluses must be big then the LOOP time !
;2.You can do the countting in main loop,then you have no time do
;any other job in the main loop.
;3.Or you can do it in a timer interrupt service.The time that the
;timer takes is the smallest width of any pluses.
;Assume:
CpuClck EQU 12000 ;12000Khz=12Mhz
TmrClck EQU CpuClck/12;1M=1000K
ReferF EQU 1000;HZ=1khz
ReferT EQU 1000;us=1ms
;Counters add 1 on both the edges of a pluse
;Results in twice the number of pulses
Counter0 EQU R0
Counter1 EQU R1
Counter2 EQU R2
Counter3 EQU R3
Counter4 EQU R4
Counter5 EQU R5
Counter6 EQU R6
Counter7 EQU R7
LastStatus DATA 20h
ORG 0000H
LJMP START
;;;;;;;;;;;;;;;;;;;;;;;;
#define SIMULATION
;comment above if runs on the target
#ifdef SIMULATION
ORG 000BH
;T0 Interrupt
PUSH PSW
PUSH ACC
CLR TR0
;
MOV TH0,#High(-ReferT)
MOV TL0,#Low(-ReferT)
MOV A,P1
JNZ SET0;<>0
;=0
MOV P1,#0FFh;8 counters
JMP Goon
SET0:
MOV P1,#0
Goon:
SETB TR0
POP ACC
POP PSW
RETI
#endif
;;;;;;;;;;;;;;;;;;;;;;;;;;
;main
START:
MOV SP,#30h
;Reset counters
MOV R0,0
MOV R1,0
MOV R2,0
MOV R3,0
MOV R4,0
MOV R5,0
MOV R6,0
MOV R7,0
;
#ifdef SIMULATION
MOV TMOD,#0000$0001B;T0=16 bits Timer
MOV TH0,#High(-ReferT);1ms=1KHZ
MOV TL0,#Low(-ReferT)
SETB EA
SETB ET0
SETB TR0
#endif
;
MOV P1,#0FFh;input
MOV LastStatus,#0FFh;as P1
LOOP:;Each loop takes 25us or more !
MOV A,P1;in order to avoid geeting different P1 value,
MOV B,A ;P1 can be read once within every loop.
XRL A,LastStatus
MOV LastStatus,B
JZ LOOP;no any changes
;which counter ?
JNB ACC.0,NotC0
INC Counter0
NotC0:
JNB ACC.1,NotC1
INC Counter1
NotC1:
JNB ACC.2,NotC2
INC Counter2
NotC2:
JNB ACC.3,NotC3
INC Counter3
NotC3:
JNB ACC.4,NotC4
INC Counter4
NotC4:
JNB ACC.5,NotC5
INC Counter5
NotC5:
JNB ACC.6,NotC6
INC Counter6
NotC6:
JNB ACC.7,More
INC Counter7
More:
JMP LOOP
END
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