How to set HPWM to generate 38khz signal? (16F870)

[richard]

Knocked this up when the remote for my aircon died , never really finished it . got a clone remote on ebay for $10 (delivered)
why bother.

this can work for any osc >= 8 MHz

'****************************************************************
'*  Name    : ir38khz.BAS                                       *
'*  Author  : RICHARD                                           *
'*  Notice  :                                                   *
'*          :                                                   *
'*  Date    : 6/30/2016                                         *
'*  Version : 1.0                                               *
'*  Notes   : REPL BRA WITH GOTO  FOR NASTY OLD CHIPS           *
'*          : OSC MUST BE AT LEAST 8 MHZ                        *
'****************************************************************
 

 
 
 
DEFINE OSC 16       ; MIN=8     TESTED  OK 8,16,32
DEFINE IRPORT  LATC 
DEFINE IRPIN  4 
define IR_1   2000     ; 1 TIME IN uS   MAX 6500 ISH
define IR_0   900      ; 0 TIME IN uS
 
cycnt       var byte  bank0       ;set to numbr of 38k cycles req then call irout  RANGE 1-255
dly         var byte  bank0      ;system

goto overasm
 asm  
_irout1                 ;entry point FOR 1 pulse   
        movlw   (IR_1/26)
        movwf   _cycnt
        BRA     _irout    ;GOTO 
_irout0 movlw   (IR_0/26) ;entry point FOR 0 pulse   
        movwf   _cycnt       
        
_irout                 ;entry point for cycnt cycles
nxbt    CHK?RP IRPORT
        BSF IRPORT ,IRPIN
        CALL dly13
        CHK?RP IRPORT
        BCF  IRPORT ,IRPIN
        CALL dly13
        RST?RP
        DECFSZ _cycnt,F
        BRA nxbt             ;GOTO
        RETURN 
dly13   movlw   (OSC-(16/OSC))
        RST?RP 
        movwf   _dly
d13         
        DECFSZ _dly,F
        BRA d13           ;GOTO
        RETURN
 endasm        
   
overasm:         
  
 

   OSCCON=$78
   ANSELA=0
   ANSELC=0

   TRISA = %111110
   TRISC = %11000011         ' set PORTC I/O
 
 
  
main:
    cycnt = 100
    call irout
    pauseus 250
    call irout1
    pauseus 250
    call irout0
    pause 50
    
goto main