How can I speed this code up? SHIFTOUT is slowing it down and I need a faster way.

[Bruce]

I think this is what Mike was talking about?

This will give you 2.5MHz with every 16th logic 1 bit stretched to 4 cycles VS 1. If you can live with this bit being a tad longer, it will definitely speed things up.

 
' define port & pin use in _Pulse
@ #DEFINE PORT PORTB ' use any port you prefer, but declare it here
@ #DEFINE PIN 6      ' same as above
 
PORTB.6 = 1       ' initialize pin to idle state
TRISB.6 = 0       ' make the pin an output
 
C1 VAR BYTE BANK0 SYSTEM
 
Main:
    C1 = 0        ' clear loop count
    CALL Pulse    ' generate 4096 pulses
    GOTO Main
 
ASM
_Pulse
    BCF PORT,PIN     ; clear pin / 1
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 2
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 3
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 4
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 5
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 6
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 7
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 8
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 9
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 10
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 11
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 12
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 13
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 14
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 15
    BSF PORT,PIN     ; set pin
    BCF PORT,PIN     ; clear pin / 16
    BSF PORT,PIN     ; set pin
    DECFSZ C1,F      ; decrement count, skip if 0
    GOTO _Pulse      ; not done, keep going
    RETURN
ENDASM

With either version, make sure you have WDT disabled.

[wolwil]

I didn't have to turn off the WDT, I think its off by default but could not find where it tells me in the manual. What will happen if its on? Would I notice it?

I do have one issue but it might just be an issue with it being on a bread board but when I use the Define OSC 20 with the 20 MHz clock it freaks out and does what ever it feels like and is sensitive to the touch but when I use no Define or Define OSC 4MHz but run it with the 20MHz clock it runs fine...I don't get it haha


Thanks again everyone, I am very grateful for all your help and suggestions