Added a PRESETS.TXT file (inside /LOOKINGGLASS folder).
Also optimized the way the spectrum signal is integrated into the cascade.
Added provision for ranges lower than 240MHz but I am afraid that at this time it will not be advisable to lower ranges any more than 240MHz, since some artifacts and frequency running - moving out of place- occurs.
I can only hope that someone with a better understanding of hackrf's inner code can fix this issue and perhaps enhance the scanning speed.
I found some "original commenting" inside the code:
// TODO: Move more low-level radio control stuff to M4. It'll enable tighter
// synchronization for things like wideband (sweeping) spectrum analysis, and
// protocols that need quick RX/TX turn-around.
Which makes me think that there are things "missing" from the portapack side of the code, for allowing serious speed sweeping. So I am concluding that with current "portapack framework" this might be "the best possible thing".
It is to be noted that the "new" internal sweep mode code is signed by:
* Copyright 2016 Mike Walters, Dominic Spill
*
* This file is part of HackRF.
Maybe Mike or Dominic can be contacted and hopefully lend a hand on enhancing this code.
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