I am currently facing a problem where when i upload my arduino program to my mega, supposedly the 3 components in it should work: biometric, rfid and keypad but apparently i can't even use any of them and the fingerprint sensor cannot even be found. When i used another arduino to test it, everything is working fine. So is it a problem with the coding or connection? I can even upload my program here if its needed.

 

Assuming they are the same arduino model then either the first arduino is faulty or the connections to it were incorrect/faulty.

 

Assuming they are the same arduino model then either the first arduino is faulty or the connections to it were incorrect/faulty.

If so, when i add in the code for the biometric, the keypad and rfid is unable to work. Any ideas why is this happening? Is it because there is not enough power going in or is it because of other reasons?

 

It is impossible to tell from here exactly why it is happening.
Do other applications work correctly with the problem arduino?

Is it because there is not enough power going in

Do you have the same power arrangement for both scenarios?

 

Look carefully at the three devices. How do you communicate to them? Is there a conflict (like two devices using the same default pins or default device ids). Using stub sketches, does each work on the Mega? Someone else asked but you didn't answer, is the other Arduino also a Mega? Note there are pin level differences between the Mega and Uno.

 

It is impossible to tell from here exactly why it is happening.
Do other applications work correctly with the problem arduino?



Do you have the same power arrangement for both scenarios?

Yes. All the power arrangements are the same. Everything is connected to a Vcc pin

 

Look carefully at the three devices. How do you communicate to them? Is there a conflict (like two devices using the same default pins or default device ids). Using stub sketches, does each work on the Mega? Someone else asked but you didn't answer, is the other Arduino also a Mega? Note there are pin level differences between the Mega and Uno.

The only thing that is similar between all the devices is the Vcc and Ground. Other than that, all the pin connections are different. We also took note of the pin level differences betweeen the different Arduinos and changed it respectively.