stevepk123

Hello I am making a laser harp, The current issue I am faced with is that the values sent from the LDR's back to the Arduino and into MAX 6 are reversing themselves. The value produced by the LDR should be high when the laser is focused on it and should drop when the beam is broken however some of the LDR's are working in the opposite manner whilst the other's work how they should, this is an intermittent problem.

To test the issue the setup is as follows:

this then connects to an isolated line on the breadboard, after this is the analog receive cable going back to the Arduino (A0-A5) then a 10k resistor on each connected to a ground rail.

The 5V and ground are both being supplied from the Ardunio

I am using an Arduino Mega 2560 the code uploaded is as follows:

and the patch to the project is attached, if any further information is needed let me know :)

6 LDR's connected to a 5v rail,
this then connects to an isolated line on the breadboard, after this is the analog receive cable going back to the Arduino (A0-A5) then a 10k resistor on each connected to a ground rail.
The 5V and ground are both being supplied from the Ardunio

void loop () {
  for(int x=0; x
    sensVar=analogRead (x);
    Serial.write(x);

and the patch to the project is attached, if any further information is needed let me know :)


ldrphotosensors-reversing-the-resistance-value-help-please

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LDR/photosensors reversing the resistance value, on an Arduino Mega 2560