At 10:55 11/06/1997 -0400, you wrote:
>Hello,
>
>Does anyone could supply me some code in C (preference), to implement a PWM
>or where i can find information about this.

As you ask for PWM code, here a sample code extracted from UMPS

    http://idls.izarbel.tm.fr/entp/techer/P01.HTM
or  http://sistudio.com/umps

This code produce a continous rectangular signal and it is easy
to change cycle modulation, just writting HiPWM and LoPWM cycles
when you need. I think "C" code will be a little slow, but it
depend of what you are searching for PWM at 10HZ or at 1KHZ

Regards,
        Philippe.

;---------------------------------------------------------------------------
-------
; PWM Output sample

INTW       equ $0C
INTStatus  equ $0D
HiPWM      equ $0E
LoPWM      equ $0F
PWMPORT    equ PORTA
Cntl       equ 0

PWMCfg     equ %11110

;---------------------------------------------------------------------------
-------
; **** RESET vector
           org 0
           goto StartUp
;---------------------------------------------------------------------------
-------
; **** INTERRUPT vector
           org 4
Intr:
           movwf INTW          ; Save W and Status registers
           swapf STATUS,W     
           movwf INTStatus
           bcf INTCON,T0IF     ; Clear TIMER 0 Int flag  

           btfsc PWMPORT,cntl  ; If cntl is Set, then Reset cntl bit
           goto Intr_1          
           bsf PWMPORT,cntl    ; be carrefull here as BSF is Read-Modify-Write
           movf HiPWM,W        ; instruction and it can change other pin state 
           movwf TMR0
           goto IntrEnd     
Intr_1:
           bcf PWMPORT,cntl
           movf LoPWM,W        ; Load LOW cycle in TIMER0
           movwf TMR0

IntrEnd:   swapf INTStatus,W   ; Restore W and Status registers
           movwf STATUS          
           swapf INTW        
           swapf INTW,W       
           retfie

;---------------------------------------------------------------------------
-------
StartUp:   
           bcf INTCON,GIE     ; *****  Disable INT
           bsf STATUS,RP0     ; Set PAGE 1 access
           movlw PWMCfg 
           movwf TRISA
           movlw %00000001    ; Timer Base = 4µS
           movwf OPTION
           bcf STATUS,RP0     ; Set PAGE 0 access
           clrf PORTA
           clrf TMR0          ; Timer 0 = 00
           movlw %10100000    ; Enable TMR0 Interrupt
           movwf INTCON
;---------------------------------------------------------------------------
-------
           movlw $A0          ; Set High pulse time to: 0x100 - 0xA0
           movwf HiPWM
           movlw $C0          ; Set Low pulse time to: 0x100 - 0xC0
           movwf LoPWM
           movwf TMR0

Loop:      goto Loop          ; Loop forever  

----------- END OF MESSAGE ----------------------------------