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m3pi 8 leds

Topic last updated 04 Dec 2011, by Don DeGregori. 2 replies
Don DeGregori
02 Dec 2011

How does one drive the 8 leds, on or off?

This is confusing for I see leds(int val)

How would I turn on 1st, and last, pin 20 and pin 13, and all the rest off?

Someone please try it.

Thanks, donde

Chris Styles
02 Dec 2011

Hi Donde,

It's implemented as an 8 bit bus with one LED per bit, so you can use a bit mask - it is probably easier to think of in Hexadecimal rather than a decimal integer.

If you're a little rusty on Hexadecimal, check out :

Hope this helps, Chris

Don DeGregori
04 Dec 2011

Thanks Chris I realize that now, but looking at the m3pi cookbook, an example would have been helpful. But, look what I did above for the topic of "Knight Rider w/o wait." and without bit shift! I started it with just 4 LEDS, but had to finish it with 8. Not very efficient code, I suppose. donde