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Support Forum » digital caliper code question

September 15, 2010
by kle8309
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I have been reading through the sample code for the digital caliber project from NK. The one thing that I don't get is why do you guys need to invert the data and clock signals:

// PIN DEFINITIONS: // PB1 --(inverted) data // PB2 --(inverted) clock

And if you guys inverted the signals, was that ever mentioned in the project description (from the tutorial) or did I just missed it.

Please explain.

September 15, 2010
by kle8309
kle8309's Avatar

Were the inverted signal due to the amplifications from the BJT's?

September 15, 2010
by kle8309
kle8309's Avatar

Nevermind, I figured it out! I studied the bjt from a book and it makes sense now. The data or clock acts as a bias controller and when it's high the PB2 or PB1 will be grounded and becomes low. Logic Inverter!

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