Why is this code not working(pwm on a 16f628a)

[Bigandrewgold]

How is the LED connected to the PIC?

Robert

EDIT: And what did you use as CONFIG and TRIS settings?

positive end is connected to the pin, negative end is grounded

@ __config _INTRC_OSC_NOCLKOUT & _WDT_ON & _PWRTE_OFF & _MCLRE_OFF & _BODEN_OFF & _LVP_OFF

Define OSC 4


LED4 VAR PortA.1
button VAR PortA.2
CMCON = 7 
VRCON = 0 
PortA=0
PortB = 000100 
T1CON = 000011
TRISA = 000100
TRISB = 000000

and this code works though, which is really confusing me

new:
if button=0 then
    led4=1
    pause 500
    led4=0
endif


goto new

[Demon]

Totally wild guess, confirm your programmer is setting the low voltage programming fuse properly:
http://www.picbasic.co.uk/forum/show...ht=#post113491

(still looking at datasheet)

Robert

EDIT: Darn, I remember reading another thread that was missing one more config to disable analog, can't find it now.

[Demon]

It must be something with the PWM, either config or syntax.

What if you use variables like this?

http://www.picbasic.co.uk/forum/show...ht=16f628a+pwm

Robert

[gadelhas]

Try this code insted

STARTMAIN:
if button=0 then   
 For Duty=0 to 255       
  PWM LED4,Duty,Cycle   
 Next   
 high led4    
 pause 1000 
   
 For Duty=255 to 0 Step -1       
  PWM LED4,Duty,Cycle    
 Next
endif

low led4
GOTO STARTMAIN

If you read the PBP Manual you will see that the PWM command after execution turn the pin input.

[aratti]

Did you declare the variable CYCLE? Did you give a value to such a variable?

If not then PWM command will not work.

Cheers

Al.

[Bigandrewgold]

Try this code insted

STARTMAIN:
if button=0 then   
 For Duty=0 to 255       
  PWM LED4,Duty,Cycle   
 Next   
 high led4    
 pause 1000 
   
 For Duty=255 to 0 Step -1       
  PWM LED4,Duty,Cycle    
 Next
endif

low led4
GOTO STARTMAIN

If you read the PBP Manual you will see that the PWM command after execution turn the pin input.

thanks, so high and low still work when the pin is a input, interesting.

[mister_e]

not interesting, it is explained in the manual...