In SX Microcontrollers, SX/B Compiler and SX-Key Tool, nate wrote:

John,

You are correct in that you can pulse an LED and have a human eye percieve the LED as 'on'.  In my experience it does seem a little dimmer when pulsed, but you can make that up by increasing the current (smaller resistor in serial with LED).  The only issue that I have always had is how to figure out how much pulsed current it is safe to run through the LED.  Most LED spec sheets that I have seen only publish a Imax(DC) rating, not a graph showing duty cycle vs current rating.  You can do emperical testing, but that does not guarantee that todays batch of LEDs will perfrom as tomorrows will (with no rating by the manuf.).

In answer to your question, you simply need to replace your code the turns on the LEDs with code that sends out a pulse train when the LEDs are supposed to be on.  Also, you can take out the caps you used for softening the LED turn-on, and simply have the SX change the duty cycle of the pulse train driving the LEDs to ramp the intensity of the LEDs.

Nate

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