555 for IR

I know there are probably better ways to get the 38 khz carrier for IR than with a 555, but I have a couple kicking around, so I rigged it up (I used R1 = 1k, R2 = 18.03k using a 22k and a 220k in parallel, and C = .001uF if you're interested).

My question is regarding how best to "turn on" the LED. Is it better to power the entire circuit off of an IO pin, or to have the circuit powered and oscillating all the time, from the 5V out, and to bring the anode of the LED low to turn it "on" and high to turn it "off"?

Surely you could use the 555's Reset pin to gate the oscillator on and off?

Aha! Yes, that seems like the right way to go. Looks like there's a bit of a delay between taking reset high and the output starting again, but that can be compensated for if it proves troublesome. Thanks!

Sorry for bumping this resolved thread, but I can't let an error stand. I put in my OP that I used a 22k and a 220k in parrallel, but that doesn't give 18.03k, it gives 20k. A 22k and a 100k give 18.03k.

However, upon further calculations, a better combo would be a 1.1k for R1, and 18.2k for R2. This, with the above specified .001uF cap gives exactly 38.4kHz, and still gives a pretty close to 50% duty cycle. The only deviation from 38.4 is now in the inherant imprecision of the components.