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| Micro Controllers Discuss all aspects of micro controllers - building them, coding them, etc. All controllers are welcome - PIC, BASIC, Z8 Encore!, etc. |
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Thread Tools | Display Modes |
22nd April 2007, 03:26 PM
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1 Hour Timer PIC 16F628A (Set Button)
Hi I’m doing a small project using PIC16F628A.It’s a one hour timer.
It’s having two digits & it’s having only two buttons, RA2 - count up button RA3 – set button RB7 – output LED I wrote a program listed below. The counting part works very well. Every time when I press the count up button it counts to 0 to 59 at each press. It works well. Code:
LIST p=16F628A
include "P16F628A.inc"
cblock 0x20
DIGIT1
DIGIT2
d1
d2
d3
d4
Flag
endc
PC EQU 02H
STATUS EQU 03H
PORTA EQU 05H
PORTB EQU 06H
TRISA EQU 85H
TRISB EQU 86H
CMCON EQU 1FH
org 0x00
movlw 0x07
movwf CMCON ;turn comparators off
bsf STATUS,5
movlw b'01100' ;RA2,RA3 inputs
movwf TRISA
movlw b'00000000' ;portB all outputs
movwf TRISB
bcf STATUS,5
clrf Flag
goto START
TABLE addwf PC,1
retlw b'00111111' ;0
retlw b'00000110' ;1
retlw b'01011011' ;2
retlw b'01001111' ;3
retlw b'01100110' ;4
retlw b'01101101' ;5
retlw b'01111101' ;6
retlw b'00000111' ;7
retlw b'01111111' ;8
retlw b'01101111' ;9
START clrf DIGIT1
clrf DIGIT2
;***********display the digit1***************
STAY bcf Flag,0 ;clear the button press flag
LOOP bcf PORTA,0 ;disable digit2
movf DIGIT1,0
call TABLE
movwf PORTB
bsf PORTA,1 ;enable digit1
call Delay
;***********display the digit2***************
bcf PORTA,1 ;disable digit1
movf DIGIT2,0
call TABLE
movwf PORTB
bsf PORTA,0 ;enable digit2
call Delay
;**********check the button is pressed*******
MAIN btfsc PORTA,2 ;test the button on portA
goto STAY
call DELAY1 ;debounce delay
btfsc PORTA,2
goto STAY
btfsc Flag,0 ;button pressed first time(calling a flag)
goto LOOP
goto COUNTUP
;**********update digit1 & digit2************
COUNTUP incf DIGIT1,1 ;increase digit1
movlw 0AH ;load with ten
xorwf DIGIT1,0 ;compare
btfss STATUS,2
goto LOOP1
clrf DIGIT1
incf DIGIT2,1 ;increase digit2
movlw 06H ;load with six
xorwf DIGIT2,0 ;compare
btfsc STATUS,2
clrf DIGIT2
LOOP1 bsf Flag,0 ;set button press flag
goto LOOP
;-------------display delay 10ms------------------------
Delay movlw 0xcF ;10ms
movwf d3
movlw 0x08
movwf d4
Delay_1
decfsz d3, f
goto $+2
decfsz d4, f
goto Delay_1
goto $+1
RETURN
;--------button debounce delay 0.0009S------------------
DELAY1 movlw 0xB3
movwf d1
movlw 0x01
movwf d2
Delay_0
decfsz d1, f
goto $+2
decfsz d2, f
goto Delay_0
goto $+1
RETURN
end
Calculating delays of course ok. But I don’t know how to detect the value at present. What’s the coding do I have to write? Where is the best place to keep the set button coding? But I tried something like this to detect the value at present. I don’t know whether its right please helps me. Code:
btfsc PORTA,3 ;test the SET button RA3 goto call DELAY1 ;debounce delay btfsc PORTA,3 goto btfsc Flag,0 goto goto Detect1 Detect1 movlw 01H ;Detects number 1 xorwf DIGIT1,0 btfss STATUS,2 goto Detect2 ;its not 1 then goto next goto Delay1min ;call 1minute delay Detect2 movlw 02H ;Detects number 2 xorwf DIGIT1,0 btfss STATUS,2 goto Detect3 ;its not 2 then goto next goto Delay2min ;call 2minutes delay Detect3 ---- ---- |
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23rd April 2007, 01:24 AM
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Your code will have a lot of overhead as the 10mS delay is just that - a 10mS delay, and your performing other tasks in between = drift
Interrupts and a higher language would make this program pie. This is a generic counter that uses interrupts instead of crude delays. It will be by far more accurate, and might open a whole new area in PIC programming you have though of before  Code:
Device = 16F628A
Xtal = 4
Dim uS as Word
Dim mS as Word
Dim S as Byte
Dim M as Byte
Dim H as Word
Symbol GIE = INTCON.7 ' Global Interrupt Enable Bit
Symbol TMR0_uS = 256 ' Set time interval of TMR0
Symbol TMR0_Enable = INTCON.5 ' This option enables TMR0 interrupts
Symbol TMR0_Overflow = INTCON.2 ' This is the TMR0 overflow flag
Symbol Snap_Shot = PORTA.0
ON_INTERRUPT Int_Sub
Goto Initialization
Int_Sub:
If TMR0_Overflow = 1 And TMR0_Enable = 1 Then
TMR0_Overflow = 0
uS = uS + TMR0_uS
If uS >= 1000 Then
uS = uS - 1000
mS = mS + 1
If mS >= 1000 Then
mS = 0
S = S + 1
If S >= 60 Then
S = S - 60
M = M + 1
If M >= 60 Then
M = M - 60
H = H + 1
EndIf
EndIf
EndIf
EndIf
EndIf
GIE = 1
Context Restore ' Restore settings and return to main program.
Initialization:
ALL_DIGITAL = True
Input Snap_Shot ' Make PORTA.0 (defined earlier as snapshot) an input
TMR0_Enable = 0 ' Disable TMR0 interrupts
uS = 0 ' Clear timer registers
mS = 0 '
S = 0 '
OPTION_REG.0 = 0 '000 - 1 : 2
OPTION_REG.1 = 0 '
OPTION_REG.2 = 0 '
OPTION_REG.5 = 0 ' Select Internal Clock Source
TMR0 = 0 ' Clear the TMR0 register
uS = 0 ' Reset all Counters
mS = 0
S = 0
M = 0
H = 0
TMR0_Enable = 1 ' Enable TMR0 Interrupts
GIE = 1 ' Enable Global Interrupts
Main:
Print At 1, 1, DEC2 H, ":", DEC2 M, ":", DEC2 S
If Snap_Shot = 1 Then
Print At 2, 1, DEC2 H, ":", DEC2 M, ":", DEC2 S, ":", DEC3 mS
EndIf
Goto Main ' Loop for ever
Click on the above link to watch the program work 
__________________
Spency. PIC Micro's - Your mind is the limit PIC's and interfacing with other devices - a PIC Basic Guide @ digital-diy.net Last edited by gramo; 23rd April 2007 at 02:55 AM. |
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23rd April 2007, 05:07 AM
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I'm a new comer to this PIC world.I cannot understand any programming language other than Assembly.Thanks gramo for your help
A little more about the operation of this circuit when I press the countup button (RA2) the two segments won't counts up automatically to 60. It counts up one by one at each press.ex:if I press count up button it will display 1.And again if I press count up button it will display 2. etc.... upto this stage its working fine.Now I want to add the other button (RA3). For example if I count up to number 3 ( three presses) and press the set button (RA3) it must call the 3 minutes delay. or if I count up to number 10 (ten presses) and press the set button (RA3) it must call the 10 minutes delay...like that same like a timer. Now my problem is how the set button (RA3) detects the value that I count ( I already counts up & in the segments now its showing the value) the value must detect the set button how to detect that? I have posted a code please see I need help. Actually I want this to do without interupts,using delay routines.... thank a lot. Last edited by Suraj143; 23rd April 2007 at 05:09 AM. |
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23rd April 2007, 07:44 AM
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Why don't you count down in your main loop. Use a bit in your Flag variable to indicate whether the clock is running or not and count the number of times through the loop. You can then count seconds and decrement your digit variables. This will have the added advantage that the digits will count down.
Something like, Code:
STAY bcf Flag,0 ;clear the button press flag LOOP bcf PORTA,0 ;disable digit2 movf DIGIT1,0 call TABLE movwf PORTB bsf PORTA,1 ;enable digit1 call Delay ;***********display the digit2*************** bcf PORTA,1 ;disable digit1 movf DIGIT2,0 call TABLE movwf PORTB bsf PORTA,0 ;enable digit2 call Delay btfsc Flag,1 ;is time running goto MAIN ; no, do other stuff decfsz LoopCount,F ;count 50 times round loop goto LOOP ;50*20mS = 1 second movlw .50 movwf LoopCount incf Seconds,F ;count seconds movlw .60 ;reached 60 xorwf Seconds,W btfss STATUS,Z goto LOOP ;no, loop around decf DIGIT1,F ;yes, decrement digit 1 btfss DIGIT1,7 ;gone negative? goto LOOP clrf DIGIT1 decf DIGIT2,F ; do second digit btfss DIGIT2,7 goto LOOP clrf DIGIT2 bcf Flag,1 ;both are zero so stop counter ;**********check the button is pressed******* MAIN btfsc PORTA,2 ;test the button on portA Mike. |
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24th April 2007, 06:33 AM
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Hi mike thanks for your usefull input.really a nice method.you have save an input button also, so I need only the countup button.
I gathered your codings and made the full code as below. But the output is always displaying "00" when I press RA2 it wont increment.all the time its showing "00" Code:
LIST p=16F628A
include "P16F628A.inc"
cblock 0x20
DIGIT1
DIGIT2
d1
d2
d3
d4
Flag
LoopCount
Seconds
endc
PC EQU 02H
STATUS EQU 03H
PORTA EQU 05H
PORTB EQU 06H
TRISA EQU 85H
TRISB EQU 86H
CMCON EQU 1FH
org 0x00
movlw 0x07
movwf CMCON ;turn comparators off
bsf STATUS,5
movlw b'01100' ;RA2,RA3 inputs
movwf TRISA
movlw b'00000000' ;portB all outputs
movwf TRISB
bcf STATUS,5
goto START
TABLE addwf PC,1
retlw b'00111111' ;0
retlw b'00000110' ;1
retlw b'01011011' ;2
retlw b'01001111' ;3
retlw b'01100110' ;4
retlw b'01101101' ;5
retlw b'01111101' ;6
retlw b'00000111' ;7
retlw b'01111111' ;8
retlw b'01101111' ;9
START clrf Flag
clrf DIGIT1
clrf DIGIT2
clrf LoopCount
clrf Seconds
;***********display the digit1***************
STAY bcf Flag,0 ;clear the button press flag
LOOP bcf PORTA,0 ;disable digit2
movf DIGIT1,0
call TABLE
movwf PORTB
bsf PORTA,1 ;enable digit1
call Delay
;***********display the digit2***************
bcf PORTA,1 ;disable digit1
movf DIGIT2,0
call TABLE
movwf PORTB
bsf PORTA,0 ;enable digit2
call Delay
;******************Mikes Codings*******************
btfsc Flag,1 ;is time running
goto MAIN ;no, do other stuff
decfsz LoopCount,1 ;count 50 times round loop
goto LOOP ;50*20mS = 1 second
movlw 32H
movwf LoopCount
incf Seconds,1 ;count seconds
movlw 3CH ;reached 60
xorwf Seconds,0
btfss STATUS,2
goto LOOP ;no, loop around
decf DIGIT1,1 ;yes, decrement digit 1
btfss DIGIT1,7 ;gone negative?
goto LOOP
clrf DIGIT1
decf DIGIT2,1 ; do second digit
btfss DIGIT2,7
goto LOOP
clrf DIGIT2
bcf Flag,1 ;both are zero so stop counter
;**********check the button is pressed**************
MAIN btfsc PORTA,2 ;test the button on portA
goto STAY
call DELAY1 ;debounce delay
btfsc PORTA,2
goto STAY
btfsc Flag,0 ;button pressed first time(calling a flag)
goto LOOP
goto COUNTUP
;**********update digit1 & digit2************
COUNTUP incf DIGIT1,1 ;increase digit1
movlw 0AH ;load with ten
xorwf DIGIT1,0 ;compare
btfss STATUS,2
goto LOOP1
clrf DIGIT1
incf DIGIT2,1 ;increase digit2
movlw 06H ;load with six
xorwf DIGIT2,0 ;compare
btfsc STATUS,2
clrf DIGIT2
LOOP1 bsf Flag,0 ;set button press flag
goto LOOP
;-------------display delay 10ms------------------------
Delay movlw 0xcF ;10ms
movwf d3
movlw 0x08
movwf d4
Delay_1
decfsz d3, f
goto $+2
decfsz d4, f
goto Delay_1
goto $+1
RETURN
;--------button debounce delay 0.0009S------------------
DELAY1 movlw 0xB3
movwf d1
movlw 0x01
movwf d2
Delay_0
decfsz d1, f
goto $+2
decfsz d2, f
goto Delay_0
goto $+1
RETURN
end
Code:
bsf Flag,1 ;after stoping the counters again set the flag bit what will be the problem? Thanks alot. |
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24th April 2007, 07:00 AM
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Woops,
Code:
;******************Mikes Codings******************* btfss Flag,1 ;is time running goto MAIN ;no, do other stuff decfsz LoopCount,1 ;count 50 times round loop You should also test your other button and do a bsf Flag,1 to start the count down. Mike. |
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24th April 2007, 12:30 PM
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Hi Mike the problem was that line now I can count up.But,
Without bsf Flag,1 the program counts well when I press count up button at each press.But after adding bsf Flag,1 code I cannot count up over the value "01" .That means when I press count up button the two segments its showing "01" cannot count any more but after 1 minute its decrement.After reaching to zero again after very long time I can count up.Again its counts to value "01" only when I press. I think the problem with the bsf Flag,1 I put this line to many places & check but cannot count up more than "01" I dont know where is the best place this line...... Code:
LIST p=16F628A
include "P16F628A.inc"
cblock 0x20
DIGIT1
DIGIT2
d1
d2
d3
d4
Flag
LoopCount
Seconds
endc
PC EQU 02H
STATUS EQU 03H
PORTA EQU 05H
PORTB EQU 06H
TRISA EQU 85H
TRISB EQU 86H
CMCON EQU 1FH
org 0x00
movlw 0x07
movwf CMCON ;turn comparators off
bsf STATUS,5
movlw b'01100' ;RA2,RA3 inputs
movwf TRISA
movlw b'00000000' ;portB all outputs
movwf TRISB
bcf STATUS,5
goto START
TABLE addwf PC,1
retlw b'00111111' ;0
retlw b'00000110' ;1
retlw b'01011011' ;2
retlw b'01001111' ;3
retlw b'01100110' ;4
retlw b'01101101' ;5
retlw b'01111101' ;6
retlw b'00000111' ;7
retlw b'01111111' ;8
retlw b'01101111' ;9
START clrf Flag
clrf DIGIT1
clrf DIGIT2
clrf LoopCount
clrf Seconds
movlw 32H
movwf LoopCount
;***********display the digit1***************
STAY bcf Flag,0 ;clear the button press flag
LOOP bcf PORTA,0 ;disable digit2
movf DIGIT1,0
call TABLE
movwf PORTB
bsf PORTA,1 ;enable digit1
call Delay
;***********display the digit2***************
bcf PORTA,1 ;disable digit1
movf DIGIT2,0
call TABLE
movwf PORTB
bsf PORTA,0 ;enable digit2
call Delay
;******************Mikes Codings*******************
btfss Flag,1 ;is time running
goto MAIN ;no, do other stuff
decfsz LoopCount,1 ;count 50 times round loop
goto LOOP ;50*20mS = 1 second
movlw 32H
movwf LoopCount
incf Seconds,1 ;count seconds
movlw 3CH ;reached 60
xorwf Seconds,0
btfss STATUS,2
goto LOOP ;no, loop around
decf DIGIT1,1 ;yes, decrement digit 1
btfss DIGIT1,7 ;gone negative?
goto LOOP
clrf DIGIT1
decf DIGIT2,1 ; do second digit
btfss DIGIT2,7
goto LOOP
clrf DIGIT2
bcf Flag,1 ;both are zero so stop counter
;**********check the button is pressed**************
MAIN btfsc PORTA,2 ;test the button on portA
goto STAY
call DELAY1 ;debounce delay
btfsc PORTA,2
goto STAY
btfsc Flag,0 ;button pressed first time(calling a flag)
goto LOOP
goto COUNTUP
;**********update digit1 & digit2************
COUNTUP bsf Flag,1 ;enable counter
incf DIGIT1,1 ;increase digit1
movlw 0AH ;load with ten
xorwf DIGIT1,0 ;compare
btfss STATUS,2
goto LOOP1
clrf DIGIT1
incf DIGIT2,1 ;increase digit2
movlw 06H ;load with six
xorwf DIGIT2,0 ;compare
btfsc STATUS,2
clrf DIGIT2
LOOP1 bsf Flag,0 ;set button press flag
goto LOOP
;-------------display delay 10ms------------------------
Delay movlw 0xcF ;10ms
movwf d3
movlw 0x08
movwf d4
Delay_1
decfsz d3, f
goto $+2
decfsz d4, f
goto Delay_1
goto $+1
RETURN
;--------button debounce delay 0.0009S------------------
DELAY1 movlw 0xB3
movwf d1
movlw 0x01
movwf d2
Delay_0
decfsz d1, f
goto $+2
decfsz d2, f
goto Delay_0
goto $+1
RETURN
end
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24th April 2007, 01:28 PM
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You should use a button on RA3 to set Flag,1 and start the timer.
Try, Code:
MAIN btfsc PORTA,3 ;test start button goto NotA3 call DELAY1 btfsc PORTA,3 goto NotA3 bsf Flag,1 ;start counter NotA3 btfsc PORTA,2 ;test the button on portA goto STAY call DELAY1 ;debounce delay btfsc PORTA,2 goto STAY btfsc Flag,0 ;button pressed first time(calling a flag) goto LOOP goto COUNTUP ;**********update digit1 & digit2************ COUNTUP incf DIGIT1,1 ;increase digit1 When you get it working, there is a much better way to do your delays. HTH Mike. |
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25th April 2007, 04:18 AM
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Hi mike,there was a small mistake in my codings,earlier I haven't add the other button (RA3) codings.
also I haven't clear the Seconds.now the count down is working. I want to change the number patern when count down. That means if I select the number "21" and set the timer the display pattern must countdown like this 21,20,19,18,17,16.........0 minutes. The problem is when the first digit comes to "0" it wont show "9" after a minute. This means after "21" its showing "20" after that it should show "19" but now its showing "20" The first digits "0" it wont detect.after detecting it must show the "9" after a minute.also it must decrement the digit2. I made some experiments like this.but cant rescue the problem. any ideas? Code:
;******************Mikes Codings******************* btfss Flag,1 ;is time running goto MAIN ;no, do other stuff decfsz LoopCount,1 ;count 50 times round loop goto LOOP ;50*20mS = 1 second movlw 32H movwf LoopCount incf Seconds,1 ;count seconds movlw 3CH ;reached 60 xorwf Seconds,0 btfss STATUS,2 goto LOOP ;no, loop around decf DIGIT1,1 ;yes, decrement digit 1 movlw 00H ;load with Zero xorwf DIGIT1,0 ;compare whether is it zero btfss STATUS,2 goto LOOP2 ;no its not zero ???????????? ;yes its not zero decf DIGIT2,1 ;do second digit movlw 00H ;load with zero xorwf DIGIT2,0 ;compare whether is it zero btfss STATUS,2 goto LOOP2 ;no its not zero clrf DIGIT2 bcf Flag,1 ;both are zero so stop counter goto START LOOP2 clrf Seconds goto LOOP |
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25th April 2007, 09:39 AM
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I see what you are trying to do now. Whenever the button is pressed it should increment the count AND start the timer. To do this you need to initialise things when the button is pressed and check the button all the time.
Try this, Code:
START clrf Flag clrf DIGIT1 clrf DIGIT2 ;***********display the digit1*************** STAY bcf Flag,0 ;clear the button press flag LOOP bcf PORTA,0 ;disable digit2 movf DIGIT1,0 call TABLE movwf PORTB bsf PORTA,1 ;enable digit1 call Delay ;***********display the digit2*************** bcf PORTA,1 ;disable digit1 movf DIGIT2,0 call TABLE movwf PORTB bsf PORTA,0 ;enable digit2 call Delay ;******************Mikes Codings******************* btfss Flag,1 ;is time running goto MAIN ;no, do other stuff decfsz LoopCount,1 ;count 50 times round loop goto MAIN ;50*20mS = 1 second movlw 32H movwf LoopCount incf Seconds,1 ;count seconds movlw 3CH ;reached 60 xorwf Seconds,0 btfss STATUS,2 goto MAIN ;no, loop around decf DIGIT1,1 ;yes, decrement digit 1 btfss DIGIT1,7 ;gone negative? goto MAIN movlw 9 ;Set digit 1 to 9 movwf DIGIT1 decf DIGIT2,1 ; do second digit btfss DIGIT2,7 goto MAIN clrf DIGIT2 clrf DIGIT1 bcf Flag,1 ;both are zero so stop counter ;**********check the button is pressed************** MAIN btfsc PORTA,2 ;test the button on portA goto STAY call DELAY1 ;debounce delay btfsc PORTA,2 goto STAY btfsc Flag,0 ;button pressed first time(calling a flag) goto LOOP goto COUNTUP ;**********update digit1 & digit2************ COUNTUP bsf Flag,1 ;enable counter clrf Seconds ;<------------moved from above movlw 32H movwf LoopCount incf DIGIT1,1 ;increase digit1 movlw 0AH ;load with ten xorwf DIGIT1,0 ;compare btfss STATUS,2 goto LOOP1 clrf DIGIT1 incf DIGIT2,1 ;increase digit2 movlw 06H ;load with six xorwf DIGIT2,0 ;compare btfsc STATUS,2 clrf DIGIT2 LOOP1 bsf Flag,0 ;set button press flag goto LOOP Mike. Last edited by Pommie; 25th April 2007 at 09:41 AM. |
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25th April 2007, 05:10 PM
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Hi Mike your earlier code worked well.no need to check the button always.Now almost 95% ok.can countup & count down.The code should be Like this. I added the RA3 (set button) to the codes.Accuracy is perfect.
Code:
;******************Mikes Codings******************* btfss Flag,1 ;is time running goto MAIN ;no, do other stuff decfsz LoopCount,1 ;count 50 times round loop goto LOOP ;50*20mS = 1 second movlw 32H movwf LoopCount incf Seconds,1 ;count seconds movlw 3CH ;reached 60 xorwf Seconds,0 btfss STATUS,2 goto LOOP ;no, loop around decf DIGIT1,1 ;yes, decrement digit 1 btfss DIGIT1,7 ;gone negative? goto LOOP2 movlw 09H ;Set digit 1 to 9 movwf DIGIT1 decf DIGIT2,1 ;do second digit btfss DIGIT2,7 ;gone negative? goto LOOP2 clrf DIGIT2 clrf DIGIT1 bcf Flag,1 ;both are zero so stop counter bsf PORTA,4 ;turn on the output goto START LOOP2 clrf Seconds goto LOOP ;**********check the button is pressed************** MAIN btfsc PORTA,3 ;test the set button on portA goto MAIN1 call DELAY1 ;debounce delay bsf Flag,1 MAIN1 btfsc PORTA,2 ;test the count up button on portA goto STAY call DELAY1 ;debounce delay btfsc PORTA,2 goto STAY btfsc Flag,0 ;button pressed first time(calling a flag) goto LOOP goto COUNTUP I added an extra output after the both digits reaches to zero.But the output goes high after increasing another extra minute. That means if I set "10" minutes it counts down nicely.after reaches to "00" (zero) the both digits, its counting another extra minute & turns on the output(but the both digits showing "00").I dont know why is this? |
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26th April 2007, 03:54 AM
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Hi now everything is working fine I made some changes in the coding.
Code:
;******************Mikes Codings******************* btfss Flag,1 ;is time running goto MAIN ;no, do other stuff decfsz LoopCount,1 ;count 50 times round loop goto LOOP ;50*20mS = 1 second movlw 32H movwf LoopCount incf Seconds,1 ;count seconds movlw 3CH ;reached 60 xorwf Seconds,0 btfss STATUS,2 goto LOOP ;no, loop around decf DIGIT1,1 ;yes, decrement digit 1 movlw 00H xorwf DIGIT1,0 btfss STATUS,2 goto CDOWN movlw 00H xorwf DIGIT2,0 btfss STATUS,2 goto CDOWN goto OUTPUT CDOWN btfss DIGIT1,7 ;gone negative? goto LOOP2 movlw 09H ;Set digit 1 to 9 movwf DIGIT1 decf DIGIT2,1 ;do second digit btfss DIGIT2,7 ;gone negative? goto LOOP2 OUTPUT clrf DIGIT2 clrf DIGIT1 bcf Flag,1 ;both are zero so stop counter bsf PORTA,4 ;turn on the output goto START LOOP2 clrf Seconds goto LOOP ;**********check the button is pressed************** MAIN btfsc PORTA,3 ;test the set button on portA goto MAIN1 call DELAY1 ;debounce delay bsf Flag,1 MAIN1 btfsc PORTA,2 ;test the count up button on portA goto STAY call DELAY1 ;debounce delay btfsc PORTA,2 goto STAY btfsc Flag,0 ;button pressed first time(calling a flag) goto LOOP goto COUNTUP |
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| Newcomers, please read! (PIC regarded) Upd. 0xD | Jay.slovak | Micro Controllers | 0 | 17th April 2005 01:04 PM |
| Watchdog timer on 16F628A | kcn | Micro Controllers | 3 | 16th April 2005 08:58 AM |
| 3000 Hour Elapsed Timer | aromph | Electronic Projects Design/Ideas/Reviews | 4 | 11th September 2004 10:30 AM |
Linear Mode
