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hello, keeping in mind all the suggestions i have modified the pgm for adc...but still the loop remains infinite .....i am not able to trace the problem even now .....please check this program and send me ur suggestions.....in one of the websites it was mentioned that comparator should b disabled for adc conversion ....so cmcon is equalised to 07h page35 in data sheets when all 3 digital i/ps o/p is off. i saw the adrech n adresl they r still zero list pf675 ; list directive to define processor #include <p12f675.inc> ; processor specific variable definitions errorlevel -302 ; suppress message 302 from list file __CONFIG _CP_OFF & _CPD_OFF & _BODEN_OFF & _MCLRE_OFF & _WDT_OFF & _PWRTE_ON & _INTRC_OSC_NOCLKOUT ;***** VARIABLE DEFINITIONS w_temp EQU 0x20 ; variable used for context saving status_temp EQU 0x21 ; variable used for context saving ;********************************************************************* * ORG 0x000 ; processor reset vector gpio equ 05h pir1 equ 0ch adresh equ 1eh adcon0 equ 1fh trisio equ 85h adresl equ 9eh ansel equ 9fh cmcon equ 19h status equ 03h clrf gpio ; initializes gpio movlw 07h ; comparator to be disabled movwf cmcon ;all three r digital means o/p off movlw 0fh ; 0f001111 so pin7 is selected movwf trisio ; since bit3 is always 1 bsf adcon0,1 ;go/done is set to start adc movlw 07h ;bit3-0 ans3:ans0 & GP0 i.e pin7 movwf ansel ;1=analog i/p &0= digital bsf adcon0,0 ; adon=1 a/d is operating bsf adcon0,7 ; adfm=1 a/d o/p is rght justified btfsc adcon0, 1 ; tests if go/done is cleared if yes then skips next ins. goto adc ; else if it is still set then continues to loop bcf pir1,6 ; adif flag is cleared since it is set after the adc ; initialize eeprom locations ORG 0x2100 DE 0x00, 0x01, 0x02, 0x03 END ; directive 'end of program' |
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adc program pic12f675 modified
Started by ●February 27, 2004
Reply by ●February 27, 20042004-02-27
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--- vaishnavi236 <> wrote: > hello, > keeping in mind all the suggestions i have modified the pgm for > > adc...but > still the loop remains infinite .....i am not able to trace the > problem even now .....please check this program and send me ur > suggestions.....in one of the websites it was mentioned that > comparator should b disabled for adc conversion ....so cmcon is > equalised to 07h page35 in data sheets when all 3 digital i/ps o/p is > > off. > i saw the adrech n adresl they r still zero > list pf675 ; list directive to define > processor > #include <p12f675.inc> ; processor specific variable > definitions > > errorlevel -302 ; suppress message 302 from > list file > > __CONFIG _CP_OFF & _CPD_OFF & _BODEN_OFF & _MCLRE_OFF & > _WDT_OFF & _PWRTE_ON & _INTRC_OSC_NOCLKOUT > > ;***** VARIABLE DEFINITIONS > w_temp EQU 0x20 ; variable used for context saving > status_temp EQU 0x21 ; variable used for context saving > > ;********************************************************************* > * > ORG 0x000 ; processor reset vector All these are set in your include file already. :-) You do not have to define them. > gpio equ 05h > pir1 equ 0ch > adresh equ 1eh > adcon0 equ 1fh > trisio equ 85h > adresl equ 9eh > ansel equ 9fh > cmcon equ 19h > status equ 03h > > clrf gpio ; initializes gpio > movlw 07h ; comparator to be disabled cmcon and trisio are in bank 1. Add: bsf STATUS, RP0 > movwf cmcon ;all three r digital means o/p off > movlw 0fh ; 0f001111 so pin7 is selected > movwf trisio ; since bit3 is always 1 Return to bank 0 with: bcf STATUS, RP0 > bsf adcon0,1 ;go/done is set to start Setting bit 1 of adcon0 starts the AtoD conversion. This is the last thing you want to do after everything is set up. > adc movlw 07h ;bit3-0 ans3:ans0 & GP0 i.e > pin7 each loop you are messing with the AtoD. Not good idea. > movwf ansel ;1=analog i/p &0= digital ansel is bank 1 again move it to bank 1 instrructions > bsf adcon0,0 ; adon=1 a/d is operating > bsf adcon0,7 ; adfm=1 a/d o/p is rght > justified > btfsc adcon0, 1 ; tests if go/done is > cleared if yes then skips next ins. > goto adc ; else if it is still > set then continues to loop only jump to the btfsc adcon0,1 instruction. $ = current program counter. $-1 = current program counter - 1. > bcf pir1,6 ; adif flag is cleared > since it is set after the adc Try something like this sequence: clrf gpio ; initializes gpio bsf STATUS, RP0 movlw 07h ; comparator to be disabled movwf cmcon ;all three r digital means o/p off movwf ansel ;1=analog i/p &0= digital movlw 0fh ; 0f001111 so pin7 is selected movwf trisio ; since bit3 is always 1 bcf STATUS, RP0 movlw 81h ; ensure that all of adcon0 is correct movwf adcon0 ; adon=1 a/d is operating bsf adcon0, 1 btfsc adcon0, 1 ; tests if go/done is cleared if yes then skips next ins. goto $-1 ; else if it is still set then continues to loop This may not be all the problems, but a start. ===== My software has no bugs. Only undocumented features. __________________________________ |
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Reply by ●February 28, 20042004-02-28
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At 11:08 AM 2/27/2004, Chad Russel wrote: >cmcon and trisio are in bank 1. Add: > bsf STATUS, RP0 Sorry, Chad - you gave wrong information. CMCON is in bank 0. In other words, move the 'bsf STATUS, RP0' line to after the write to CMCON. dwayne -- Dwayne Reid <> Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax Celebrating 20 years of Engineering Innovation (1984 - 2004) .-. .-. .-. .-. .-. .-. .-. .-. .-. .- `-' `-' `-' `-' `-' `-' `-' `-' `-' Do NOT send unsolicited commercial email to this email address. This message neither grants consent to receive unsolicited commercial email nor is intended to solicit commercial email. |
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Reply by ●February 28, 20042004-02-28
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Don't be sorry, I'm sorry. I did not run a simulation, just
typed wrong or misread the data sheet. Thanks. --- Dwayne Reid <> wrote: > At 11:08 AM 2/27/2004, Chad Russel wrote: > > >cmcon and trisio are in bank 1. Add: > > bsf STATUS, RP0 > > Sorry, Chad - you gave wrong information. CMCON is in bank 0. > > In other words, move the 'bsf STATUS, RP0' line to after the write > to CMCON. > > dwayne > > -- > Dwayne Reid <> > Trinity Electronics Systems Ltd Edmonton, AB, CANADA > (780) 489-3199 voice (780) 487-6397 fax > > Celebrating 20 years of Engineering Innovation (1984 - 2004) > .-. .-. .-. .-. .-. .-. .-. .-. .-. .- > `-' `-' `-' `-' `-' `-' `-' `-' `-' > Do NOT send unsolicited commercial email to this email address. > This message neither grants consent to receive unsolicited > commercial email nor is intended to solicit commercial email. ===== My software has no bugs. Only undocumented features. __________________________________ |
