2 questions: FFT, WakeUp

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Hi, I'm Julián. I have 2 questions:

1. Has anybody C code (I'm using WinAVR gcc) of an FFT for a Mega AVR? No matter wich Mega.

2. I have a problem on an ATMega8: I send it to sleep, and try to wake up with the external INT0 interrupt. It works well when the mode is Idle, but doesn't work on any other mode. The IRQ is configured in level, and the pin has activated the internal pull-up and goes down via a 100 Ohm Resistor to GND. Had anybody got this problem? I'm using the hi level funcions from the gcc API:

sei();
set_sleep_mode(SLEEP_MODE_IDLE); //This works;
//set_sleep_mode(SLEEP_MODE_PWR_DOWN); //Doesn't work.
//set_sleep_mode(SLEEP_MODE_ADC); //Doesn't work.
sleep_mode();

The micro goes into sleep, but does not wake up (except for idle).
Thanks, Julián.

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juliandasilva wrote:

1. Has anybody C code (I'm using WinAVR gcc) of an FFT for a Mega AVR? No matter wich Mega.

there are so many FFT, depending on data types, memory requested, float support..You may have a look at http://www.fftw.org/benchfft/fft....

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I got the fixfft code working on a 128... only works up to 256 points.....

https://www.avrfreaks.net/phpBB2/...

Imagecraft compiler user

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Thanks for the the link and the FFT code. I will look them and try the code.
Julián.
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