Hi There!,
I'm very interested in using the FrequencyMeasure library to measure low frequency light waves. Up to now I just have an Adruino Uno but if the project develops I can see I would be better to get a Teensy.
To test the frequency measuring part of the project I am using a 555 timer ic pulse generator set at 100Hz approx. see circuit
https://drive.google.com/file/d/0B7pY4dDKKRISWUxtZmxieUlmMG8/edit?usp=sharing
I have connected the output to digital pin 8 on the uno and grounded the circuit to digital gnd on the board. The problem is that the output is not working. When I connect the signal to pin8 I get a random frequency in the results (either serial monitor or LCD) when I take the signal off the pin the value changes to another random frequency and if I touch the pins again another value is output etc.
I am just a beginner really with electronics and have little experiance with these microcontroller platforms so I would be greatful of some help and advice.
My questions are firstly:-
Can I use that circuit 'as is' to provide the signal. or is it inadequate in some way?
Should I be using the digital ground as a common ground for the external circuit?
What is likely to be the issue causing the failure to measure the frequency correctly?
my gut feeling (not very scientific) is a problem with the signal i.e. strength, waveform, voltage etc.
Cheers
Nigel
I'm very interested in using the FrequencyMeasure library to measure low frequency light waves. Up to now I just have an Adruino Uno but if the project develops I can see I would be better to get a Teensy.
To test the frequency measuring part of the project I am using a 555 timer ic pulse generator set at 100Hz approx. see circuit
https://drive.google.com/file/d/0B7pY4dDKKRISWUxtZmxieUlmMG8/edit?usp=sharing
I have connected the output to digital pin 8 on the uno and grounded the circuit to digital gnd on the board. The problem is that the output is not working. When I connect the signal to pin8 I get a random frequency in the results (either serial monitor or LCD) when I take the signal off the pin the value changes to another random frequency and if I touch the pins again another value is output etc.
I am just a beginner really with electronics and have little experiance with these microcontroller platforms so I would be greatful of some help and advice.
My questions are firstly:-
Can I use that circuit 'as is' to provide the signal. or is it inadequate in some way?
Should I be using the digital ground as a common ground for the external circuit?
What is likely to be the issue causing the failure to measure the frequency correctly?
my gut feeling (not very scientific) is a problem with the signal i.e. strength, waveform, voltage etc.
Cheers
Nigel
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