Originally Posted by
jcleaver
some mention of the correct pullup but no diagrams \
believe this could go a long way for help
Well at the risk of sounding harsh, " PULLUP " Pulls UP, up to where? To the supply voltage. PULLDOWN pulls Down to Ground. There now you have a schematic. NOW, as to the value of those pullups. It depends upon what voltage you are using, what you want it to be, and how much current you want them to draw. OHMs law involved here. imagine an LED in series with a resistor.
one end is hooked to power + the other hooked to ground. We will call the resistor Rs. If you have a supply of 5 volts and an LED operating on 1.5 volts and the LED specs call for 20ma then: Rs = Vin - V led / I led or Rs = ( 5 - 1.5) / .02, or Rs = 175. General rules of thumb apply, many people use 10K resistors as port pullups a load of .0005 amp at 5 volts.
If you do not believe in MAGIC, Consider how currency has value simply by printing it, and is then traded for real assets.
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Gold is the money of kings, silver is the money of gentlemen, barter is the money of peasants - but debt is the money of slaves
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There simply is no "Happy Spam" If you do it you will disappear from this forum.
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