user25487: Hi dears
I want help I’m in begging in programming. I want use more than 64 analog pin for ldr photoresistor in single reading. Because I can’t   use digital pin 0-1.
Any methods I can use ,,,,
And How??

user42015: You basically have 2 ways to do this:

You can use multiplexer chips, which are capable of carrying analog signals. Then you can connect the multiplexers to an analog input and the inputs of the multiplexers to the LDRs. Each multiplexer gets controlled over multiple digital pins (depending on the exact chips; it may be good to find one with a serial interface like I2C) and connects the analog input with one of the LDRs. Which one depends on the control inputs.

You can use external ADCs (Analog Digital Converters, like the one in the Arduino). These are normally controlled over a serial interface (like I2C) and give you multiple analog inputs at once. For example this board from adafruit, which gives you 16 analog inputs and is controlled over only 2 lines (I2C, A4 and A5 on an Arduino Uno/Nano). This is probably a simpler way, though for a higher cost. If you want to to cheaper than the linked board, you may wanna use blank ADC chips instead of a breakout board.



user87999: I've just built a board that allows an Arduino to access 192 analog inputs - one at a time of course. More is possible. It uses 4067 16 x 1 analog mux chips. A single 8 bit port controls it.
Need a schematic?

25487: <p>Hi dears
I want help I’m in begging in programming. I want use more than 64 analog pin for ldr photoresistor in single reading. Because I can’t   use digital pin 0-1.
Any methods I can use ,,,,
And How??</p>
 42015: <p>You basically have 2 ways to do this:</p>
<ul>
<li><p>You can use multiplexer chips, which are capable of carrying analog signals. Then you can connect the multiplexers to an analog input and the inputs of the multiplexers to the LDRs. Each multiplexer gets controlled over multiple digital pins (depending on the exact chips; it may be good to find one with a serial interface like I2C) and connects the analog input with one of the LDRs. Which one depends on the control inputs.</p>
</li>
<li><p>You can use external ADCs (Analog Digital Converters, like the one in the Arduino). These are normally controlled over a serial interface (like I2C) and give you multiple analog inputs at once. For example <a href="https://www.adafruit.com/product/1085" rel="nofollow noreferrer">this board from adafruit</a>, which gives you 16 analog inputs and is controlled over only 2 lines (I2C, A4 and A5 on an Arduino Uno/Nano). This is probably a simpler way, though for a higher cost. If you want to to cheaper than the linked board, you may wanna use blank ADC chips instead of a breakout board.</p>
</li>
</ul>
 87999: <p>I've just built a board that allows an Arduino to access 192 analog inputs - one at a time of course. More is possible. It uses 4067 16 x 1 analog mux chips. A single 8 bit port controls it.
Need a schematic?</p>
