<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
; Audio out   Audio in
-odac           -iadc    -t60 ;;;RT audio I/O
; For Non-realtime ouput leave only the line below:
; -o tempo.wav -W -t60 ;;; for file output any platform
</CsOptions>
<CsInstruments>

; Initialize the global variables.
sr = 44100
kr = 4410
ksmps = 10
nchnls = 1

; Instrument #1.
instr 1
  kval tempoval

  printk 0.1, kval

  ; If the fourth p-field is 1, increase the tempo.
  if (p4 == 1) kgoto speedup
    kgoto playit

speedup:
  ; Increase the tempo to 150 beats per minute.
  tempo 150, 60

playit:

  a1 oscil 10000, 440, 1
  out a1
endin

</CsInstruments>
<CsScore>

; Table #1, a sine wave.
f 1 0 16384 10 1

; p4 = plays at a faster tempo (when p4=1).
; Play Instrument #1 at the normal tempo, repeat 3 times.
r3
i 1 00.00 00.25 0
i 1 00.25 00.25 0
i 1 00.50 00.25 0
i 1 00.75 00.25 0
s

; Play Instrument #1 at a faster tempo, repeat 3 times.
r3
i 1 00.00 00.25 1
i 1 00.25 00.25 0
i 1 00.50 00.25 0
i 1 00.75 00.25 0
s

e

</CsScore>
</CsoundSynthesizer>