I'm still new at this arduino thing. When I first began I needed a button array. The tutorial I went by used pull down resistors for the switches. I'm learning now that the arduino has built in pull up resistors so all we need to do is wire one side of switch and other to ground then set the switch …

Why would anyone ever use pull down resistors for momentary on switch?

perhof February 19, 2013, 1:12pm 4

Grumpy_Mike:
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Nice write-up Mike!