ECCP module problem

why is this code not working on 18F1320.any ideas!!!!

Define OSC 8
ADCON1 = 7

DUTY var WORD

P1A var PORTB.3 ' ECCP pin defines . Replace those with your actual device pins
P1B var PORTB.2
P1C var PORTB.6
P1D var PORTB.7
TMR2IF var PIR1.1 ' TMR2 interrupt flag



P1A=1 'Tristate
P1B=1 ' Tristate
P1C=1 ' Tristate
P1D=1 'Tristate
PR2 = 249 ' set PR2 to 249 , that is 1Khz PWM frequency
CCP1CON =0 ' PWM generator stopped
CCPR1L = 0 ' zero Duty Cycle
'CLEAR TMR2IF
TMR2IF=0



FORWARD:
DUTY=200
CCP1CON=0 ; stop the PWM generator
P1A=0 ' P1A = 1 ; P1A = active
P1B=1 ; P1B = tristate
P1C=1 ; P1C = tristate
P1D=0 ; P1D = PWM modulated
;------------------------
CCP1CON.4 = DUTY.0 ; here we stat loading the CCPR1
CCP1CON.5 = DUTY.1 ; with the value of DUTY Cycle parameter
CCPR1L = DUTY >> 2 ;
;-----------------------
CCP1CON = %01001100 ; set CCP1CON to full bridge , high output, Forward
T2CON = %00000101 ; start TMR2 , also TMR2 prescaler 1:4
WHILE TMR2IF = 0
WEND ; wait for a TMR2 period to expire
RETURN

Quote:

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Originally Posted by hell_pk

why is this code not working on 18F1320.any ideas!!!!

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Code:

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P1A  var PORTB.3    ' ECCP pin defines .
P1B  var PORTB.2   
P1C  var PORTB.6   
P1D  var PORTB.7   
TMR2IF  var PIR1.1 ' TMR2 interrupt flag



    P1A=1        'Tristate
    P1B=1        ' Tristate
    P1C=1        ' Tristate
    P1D=1        'Tristate

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Those are changing the PORT value, not it's input/output state.

Try TRISB.x for P1A-D.
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Hi!
still not working!!!

Is there more to your program?

If not, then the FORWARD routine is RETURNing but it wasn't called with a GOSUB.

Also,

Code:

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;------------------------
CCP1CON.4 = DUTY.0 ; here we stat loading the CCPR1
CCP1CON.5 = DUTY.1 ; with the value of DUTY Cycle parameter
CCPR1L = DUTY >> 2 ;
;-----------------------
CCP1CON = %01001100 ; set CCP1CON to full bridge , high output, Forward

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By setting CCP1CON after seting to 2 LSB's of the dutycycle, it overwrites those bits and you lose resolution.
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thanks its done with a little bit of messing around.i wasnt using my head and was relying too much on forum help.
btw thanks to fanie & gabi as well. :)