erikkaashoek

/* fix_fft.c - Fixed-point in-place Fast Fourier Transform  */
/*
  All data are fixed-point short integers, in which -32768
  to +32768 represent -1.0 to +1.0 respectively. Integer
  arithmetic is used for speed, instead of the more natural
  floating-point.

  For the forward FFT (time -> freq), fixed scaling is
  performed to prevent arithmetic overflow, and to map a 0dB
  sine/cosine wave (i.e. amplitude = 32767) to two -6dB freq

erikkaashoek

/*
Si5351 VFO

By LA3PNA  27 March 2015
Modified by NT7S  25 April 2015

Modified to be Si5351 Arduino v2 compliant by NT7S  21 Nov 2016

This version uses the new version of the Si5351 library from NT7S.
see: http://arduino.cc/en/Reference/AttachInterrupt for what pins that have interrupts.

erikkaashoek

DEVICE_ID="pmsensor-" .. string.format("%02X", node.chipid())

BOOT_WAIT = 3
DWEET_INTERVAL = 60
LED_PIN = 4

pm25 = nil
pm10 = nil

function led(state)