http://earthshinedesign.co.uk/ASKManual/ASKManual.pdfYou should save that, and read through it later.. but for now, scroll down to the Project where he uses 595's, he has some code that makes them a bit easier to use. And explains alot about how they work.
shiftOut(dataPin, clockPin, MSBFIRST, B10000000)shiftOut(dataPin, clockPin, MSBFIRST, B01000000)shiftOut(dataPin, clockPin, MSBFIRST, B00100000)
yep, but a array and a loop would make it easier
Is it safe to have both the cathode and anode of an LED high at the same time? I assume nothing bad will happen...but you never know.
Grounding both ends of a LED (LOW) would result in no current flow. Having +5vdc applied to both ends (HIGH) would also result in no current. No harm in either case.Having ground on the anode and +5vdc on the cathode would result in no current flow because it is a reversed bias condition, Again no harm as long as the applied reverse voltage does not exceed the maximum reverse voltage specification of the diode (see specific LED datasheet).Having a ground on the cathode and +5vdc on the anode would result in forward current flow and if not limited externally from the LED (either with a resistor, constant current source, etc) could of course damage the LED or the device driving the LED due to excessive current flow above the LED's maximum foward current specification.Lefty
I could possibly get away with inputting only about 3.5 volts, and then using LEDs that require that amount.
if you don't write to the register again that 1 led will remain lit, so you have to refresh the "screen" fast enough to display a dot matrix image to the eye that doesn't flicker