anchor.diff:                          name
                           :start #x1001))
           (with-input-file i (+ "obj/" src ".downsampled." ! ".wav")
  +          (when *make-test-pulses?*
  +            (dotimes (j 8)
  +              (adotimes ((half *nipkow-pulse-rate*))
  +                (write-byte (+ (nipkow-shortest-pulse) j) o)
  +                (write-byte (- (nipkow-longest-pulse) j) o))))
             (? *video?*
                (with-input-file video "obj/nipkow.dat"
                  (wav2pwm o i video))
                (wav2pwm o i))))
  -; XXX Too inaccurate to make working cassettes.
  -;      (with-input-file i tapname
  -;        (with-output-file o (+ "compiled/" src "." ! ".tap.wav")
  -;          (tap2wav i o 48000 (cpu-cycles *tv*))))
  +      (with-input-file i tapname
  +        (with-output-file o (+ "compiled/" src "." ! ".tap.wav")
  +          (tap2wav i o 44100 (cpu-cycles *tv*))))
         (sb-ext:run-program "/usr/bin/zip" (list (+ tapname ".zip") tapname)))))
   
   (unless *mario-pal-only?*
  
positive.code: (= *model* :vic-20)
  
  (load "bender/vic-20/cpu-cycles.lisp")
  
  (defvar *video?* nil) ;"video.mp4")
  (defvar *video-end* "20")
  
negative.code: (defvar *nipkow-disable-interrupts?* t)
  (defvar *nipkow-fx-border?* t)
  (defvar *mario-pal-only?* nil)
  (defvar *make-test-pulses?* nil)
  
  (defvar *nipkow-pulse-rate* 4400)
  (defvar *bandwidth* 16)
  