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mushin · 09-13-2005, 02:54 PM

For the simplist solution, you should be able to use the parallel port to PWM the RGB channels to get the color you want. Since the PC is doing all the logic for the effects, and the LPT port should be fast enough to hold a color, you don't need any additional controller hardware. Take 3 data pins, one for each color, wired to transistors to switch power to your LEDs. You'll probably need to duty cycle down to 1/16 to get a good color range, and refresh them at around a kHz to eliminate flicker. After that it's all software.

09-13-2005, 02:54 PM	#5
mushin Maximum Bitrate Join Date: Aug 2004 Location: SE Michigan Vehicle: MR2 Spyder Posts: 750 My Photos: ()	For the simplist solution, you should be able to use the parallel port to PWM the RGB channels to get the color you want. Since the PC is doing all the logic for the effects, and the LPT port should be fast enough to hold a color, you don't need any additional controller hardware. Take 3 data pins, one for each color, wired to transistors to switch power to your LEDs. You'll probably need to duty cycle down to 1/16 to get a good color range, and refresh them at around a kHz to eliminate flicker. After that it's all software.