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Member #1250

Member Since: February 10, 2006

Country: United States

  • I figured out the problem with the DO signal. The Latch signal (50 usec low) is at the end of the data string, not between the 24-bit sequence for each LED. If you leave too much time (> ~5 usec) between 24-bit data, the 1st LED thinks it is at the end of the string and never passes the data through using DO. We need at 'real' datasheet with actual pinouts, timing diagrams, electrical characteristics for the DO line, etc!

  • I didn't have any trouble getting the 1st LED in a string to work by bit-banging with a PIC, but I'm getting no signal from the DO pin. So, the 1st LED changes colors, but the subsequent LED's in the daisy-change are blue (the start-up color). I tried disconnecting the 1st LED, pulling it up with a 1k resistor, but this just gives a DC voltage to rise from ground to ~2V. Maybe I have a defective batch? I tried switching other LED's into the 1st position with the same result. I'm using the pinout that wawison described.

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