Rott You can connect a 5 volt regulated power supply to the two screw terminals should back feed the arduino needs a few more tweaks that cool looking thing is your reverse voltage protection the jumpers up near the rtc gives the option to use 18,19 or 20, 21
happy now root
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Redtop I have some of the boards the screw sheild I need to clean up then off to the board house what I would like to do is stack the current board then a second board with a ULN and port expander now I am not sure what pins the port expander uses and may need a bit of guidance I have seen two diffrent connections and confused myself
Thanks rott I don't see hardly any screw sheilds like this at least I only found two and one was like almost 100 bucks but this board has the option of switching pins for the rtc or disconnecting it all together a handy feature if your using a port expander I beefed up the power traces if you want to back feed the arduino
Marc
Redtop that works
now as for the uln what pins on the arduino does it connect to I know it is used for tthe dosing pumps I also know how to connect the pumps to it and are there two uln ?
just when you thought it couldn't get any better
led power indicator , reset switch , proto section , power breakout next to proto +3v, +5v and GND
RTC with jumpers to enable or disable resistors or use pins 18,19 or 20,21 or just disable entire RTC
Terminals to back feed your arduino with regulated 5 volts plus reverse polarity protection and of course screw terminals for all pins
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