> I inadvertently connected an LED directly to RC5 with no current limiting
> resistor.  It is flashing brightly at 1 Pulse Per Second.  The PIC port can only
> source about 25 mA and that's about right for a bright LED.  Other than the
> current draw is there any down side to driving the LED directly?

According to Kurt Kuhlmann of Microchip, running an LED directly from a
PIC pin and ground, power supply voltage up to 5 volts, is perfectly OK.
It will not draw more than 25 mA.

Connecting the LED from PIC to +5, on the other hand, is likely to draw
more than 25 mA and is not recommended.

That's because the PICs output MOSFETs have different on-resistances, the
high side being P-channel types.

Cheers,

Bob

P.S. use a resistor anyway :)

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