Arduino Multiplexer Question

Yes you can. As many as you want. First multiplexer takes 4 outputs from the arduino. On the first multiplexer hook up 4 more... and so forth...

You can also use I2C multiplexer.. Perhaps easier.
 
Yes. I already tried on my FCDS prototype, but there is a little correction for Daniel's post. You need 4 digital and 1 analog pins from arduino. For the next multiplexer you should connect the same digital pins and an additional analog pin and the whole process go on.

And of course you can save some pins withI2C multiplexers.

Mike, how much pins do you need? And analogs or digitals?
 
FERCSA said:
Yes. I already tried on my FCDS prototype, but there is a little correction for Daniel's post. You need 4 digital and 1 analog pins from arduino. For the next multiplexer you should connect the same digital pins and an additional analog pin and the whole process go on.

And of course you can save some pins withI2C multiplexers.

Mike, how much pins do you need? And analogs or digitals?

I am researching this question also as I never used a MUX but need to as I buildatester for myself.

I saw a way to addresstwo 16:1 MUX chips by connecting the address lines in parallel, just be sure toadda2:1 mux for the chip select line... like this:http://word-to-html-images.s3.amazonaws.com/9780495471691/1401-9-16p-i1.png

That diagram is labeled funny, withlines calledABCDE, but I think the A is the chip selectline and BCDE would bethe address lines.
On a 16 channel MUX spec sheet, they call the address lines A0 A1 A2 A3 and the chip select isEN... so we should put the 2:1 mux on the EN line to select one of the MUX chips at a time. The analog pin is required to do analog reads for the selected input.

I want to do some logging for up to 32xTP4056 chargers, and think I may need 4 pairs of 16:1 MUXchips to control individual slots (on or off), sensevolts, sense temperature, and show an overtemp LED for each slot.

Next I willre-read about your design and learn more aboutI2C.

Gary G.
 
I'm getting into it myself so all this is theoretical to me. Here's the thing the way I understand it, the BCDE is basically the 4 bits you're trying to control. In the binary world, the 4 bits from 0000 to 1111 there's a total combinations of 16 possibilities. So by switching the digital lines on and off, like 0001 is 1 and 0010 is 2, is how you would achieve your 16 channels you can open one at a time. You also need an analog line to read the input. So the D0 to D3 controls which 'Gate' to open, and the A0 will be the one that takes the reading.

Now you can throw another 2 to 1 MUX in the equation, but you need to drive it with another digital line. You can do away with that. So what you do is drive both 16 MUX with the same 4 digital lines (D0 to D3). So you basically send the instruction to tell both MUX to let's say open Gate 1 (my term). Now the digital lines only control what Gate to open. In order to read the signal, you read through the analog lines. So if you hook one MUX to A0 and the other MUX to A1, then you just pick which MUX you want to read based on which analog input you choose.
 
That's a nifty idea. I hadn't thought of that myself. Pretty clever :) And if you had a 4:1 MUX to start off with, you could do 64 lanes that way and use A0 - A3. Interesting.

:Two thumbs up: for you!! :D
 
Ok, then we can continue with this thread without ya, mike :p Altho, I'll probably start my own when I get to that point with my need for MUX's.
 
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