RE: Arduino 24v I/o shield question

masterbri — Fri, 02 Mar 2018 05:27:06 GMT

I was reading up on this subject some earlier today and came across this piece: http://tronixstuff.com/2011/08/26/tutorial-maximising-your-arduinos-io-ports/

i think this explains exactly what I was after. Using the binary, hexadecimal or decimal equivalent of which I/o I’m trying to use at any given time.

thank you all for your help!!

please bear with me, I’m still learning!

dougw — Thu, 01 Mar 2018 05:46:09 GMT

It uses an I2C I/O expander (MCP23017) on Arduino Pins A4 and A5.

You need to send data via I2C to access most of the I/O.