LED A4 does not light?

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FLJ
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LED A4 does not light?

Postby FLJ » Tue Feb 07, 2012 2:43 am

Hello,
I am new at Flowcode. I bought the PIC developpement board #3. I am able to programmed all the examples and I am able to test different PIC micro. I can simulate to turn ON each LED on port A and display any messages on the LCD display. The LED A4 never light up and the signal is always low on a scope.
The simulation shows that A4 should light up. Is there something that I don't do right?

Thank you for your help.

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STibor
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Re: LED A4 does not light?

Postby STibor » Tue Feb 07, 2012 5:57 am

Hi!
The RA4 is generally open-drain output.
The LEDs and a resistor in the VDD-to RA4.
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Re: LED A4 does not light?

Postby FLJ » Tue Feb 07, 2012 12:30 pm

Thank you.
...and what should I do? Do I have to add a pull up on the developpement bord?

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Benj
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Re: LED A4 does not light?

Postby Benj » Tue Feb 07, 2012 2:59 pm

Hello,

If your using the HP488 Dev board then you can add the pull up resistor (4.7K or 10K) between +V and RA4 using the screw terminals on the side of the Dev board.
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