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Break ouy of loop possable?

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1Steveo

New Member
I need a litte help with picbasic.
For the life of me I can not figure out break out of the first delay in my code until it has finished.
Can someone take a look at my code and give me some suggestions?

Thanks ahead.
Steve

DEVICE 12F629
CONFIG INTRC_OSC_NOCLKOUT,WDT_OFF,MCLRE_OFF,CP_OFF,BODEN_ON
XTAL 4
ALL_DIGITAL = TRUE
TRISIO = %00001000
SYMBOL PIR = GPIO.3
SYMBOL BUZ = GPIO.2

CHECKIT:
WHILE PIR <> 0
DELAYMS 60000
BUZ = 1
DELAYMS 500
BUZ = 0
WEND
DELAYMS 3000
BUZ = 1
DELAYMS 1000
BUZ = 0
DELAYMS 3000

GOTO CHECKIT
END
 

bmcculla

New Member
I'm not don't know basic very well but it seems like you can add an IF statement with a GOTO to jump out of the loop. If you want to get out of the loop durring the DELAY I don't think there's a way to do that without rewriting the delay function. You might want to look into interrupts to solve this problem. Instead of delat you set up a timer interrupt to generate the appropreate delays. This lets your processor do something useful durring this time.

Another technique that I use goes as follows (in pseudo code):

while PIR <> 0

if done delaying
buz = buz xor 1 //simple way to toggle BUZ

do something useful here

WEND

each time through the loop it checks the timer to see if its done delaying. If its not done delaying then it does something else then goes back through the loop.

Brent
 

ivancho

New Member
I am not sure what PICBASIC you are using... I don't think is the one from melabs

But here is what I see.... the Delayms function will probably make the PIC sit there and wate time... and DO NOTHING! not even checking its inputs.
So you are delaying for 600000ms that is 10 minutes, while the PIC sits there for 10 minutes, it will do nothing, nor respond to anything. IT wil jus SIT there. Then you will have some micoseconds after the BUZ = 1 to make sure that PIR is not 0. If it is a switch with the bouncing and all will miss your "window" and it then will go back to the 10 minutes waiting period of doing what?..... NOTHING :)

Instead of delaying for 60000 with DELAYMS you should delay and check your inputs something like this:

Code:
WHILE PIR <> 0 
  For X = 0 to 60000
     DELAYMS 1
     If   PIR <> 0 then EXITWEND
  Next X 
   
  BUZ = 1 
  DELAYMS 500 
  BUZ = 0 
WEND 

EXITWEND:
That way the inputs are checked every 1ms for 10 minutes, and if during that time the PIR goes high then it exits the WHILE statement. You could also use interrupts, but if you are not too picky that it has to be 10minutes exactly it would not be worth the hazzle!

Ivancho
 
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