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         SCOPEXT by Smack/Infect
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 this tiny prog is some kind of a 'sampling oscilloscope'. it uses
 the parallel port sampler, if you don't have one, then this prog
 will be useless for you.

 requires: AGA/68020+/OS V37+

 the sampling rate is 16kHz so frequencies above 8kHz will not be
 visible. if you say now 'this is not very much' then i wanna tell you:
 16kHz means that during every pal-frame we receive 320 bytes so it fits
 perfectly on a lores screen. and there's simply not enough cpu power
 on todays amigas to use a higher resolution for this task. (i think ;-)

 the prog is controlled via keyboard so try these:
  F1 - lores 20ms display
  F2 - hires 40ms display
  F3 - single dot
  F4 - eight average dots
  F5 - line  (*)
  F6 - solid (*)
  F7 - spectrum analyzer (on 40ms display only!)
  F9 - show idle cpu time
  F10- freeze display
  ESC- exit

 NOTE: the modes marked with (*) need different amounts of cpu time
       depending on the current sample data.
       if the screen borders get red then the plotting routine runs
       too slow. to avoid this you could  a) get a powerful cpu and
       some _fast_ fast ram  b) use a faster plotting mode (F3 or F4).

 and remember: this is only a programming experiment. you can't claim
 me for any damages or trouble my prog could cause. it's all your
 fault coz you dared to start it ;-)


 contact me if you want:
     Michael Henke
     Praetorius-Str.1/205
     06124 Halle
     Germany



 HISTORY

 170195
  -first release

 190195
  -FFT spectrum analyzer implemented
    it uses a 128-point fourier transformation which seems to be quite
    accurate. each bar represents a band of about 125Hz, the 64 bars
    go upto 8kHz.
    NOTE: in this first version there are some 'inaccuracies' in the
    frequency range. i will fix it as soon as i get some equipment to
    calibrate the frequencies. and maybe i'll implement 'acoustic scaling'
    which linearizes the spectrum like the human ear does.
 200195
  -spectrum analyzer calibrated (using Masque's Chicken Dialer!!)
  -peak levels implemented