ctrl7

ctrl7
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ctrl7 — Allows a floating-point 7-bit MIDI signal scaled with a minimum and a maximum range.

Description

Allows a floating-point 7-bit MIDI signal scaled with a minimum and a maximum range.

Syntax

idest ctrl7 ichan, ictlno, imin, imax [, ifn]

kdest ctrl7 ichan, ictlno, kmin, kmax [, ifn]

adest ctrl7 ichan, ictlno, kmin, kmax [, ifn] [, icutoff]

Initialization

idest -- output signal

ichan -- MIDI channel (1-16)

ictlno -- MIDI controller number (0-127)

imin -- user-defined minimum floating-point value of output

imax -- user-defined maximum floating-point value of output

ifn (optional) -- table to be read when indexing is required. Table must be normalized. Output is scaled according to imax and imin val.

icutoff (optional) -- low pass filter cut-off frequency for smoothing a-rate output.

Performance

kdest, adest -- output signal

kmin -- user-defined minimum floating-point value of output

kmax -- user-defined maximum floating-point value of output

ctrl7 (i- and k-rate 7 bit MIDI control) allows a floating-point 7-bit MIDI signal scaled with a minimum and a maximum range. It also allows optional non-interpolated table indexing. Minimum and maximum values can be varied at k-rate.

ctrl7 differs from midic7 because it can be included in score-oriented instruments without Csound crashes. It also needs the additional parameter ichan containing the MIDI channel of the controller.

The a-rate version of ctrl7 outputs an a-rate variable, which is low-pass filtered (smoothed). It contains an optional icutoff parameter, to set the cutoff frecuency for the low-pass filter. The default is 5.

Examples

Here is an example of the ctrl7 opcode. It uses the file ctrl7.csd.

Example 163. Example of the ctrl7 opcode.

See the sections Real-time Audio and Command Line Flags for more information on using command line flags.

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
-odac   -M0  ;;;RT audio I/O with MIDI in
;-iadc    ;;;uncomment -iadc if RT audio input is needed too
</CsOptions>
<CsInstruments>

sr = 44100
ksmps = 32
nchnls = 2
0dbfs = 1

instr 1	; expects MIDI controller input on channel 1
; run and move your midi controller to see result

imax = 1
imin = 0
ichan = 1 
ictlno = 7
 
	initc7	1, 7, 1			; start at max. volume
kamp	ctrl7	ichan, ictlno, imin, imax	; controller 7
	printk2	kamp
asig	oscil	kamp, 220, 1
	outs	asig, asig

endin

</CsInstruments>
<CsScore>
f 1 0 4096 10 1

i1 0 20

e
</CsScore>
</CsoundSynthesizer>

	Note
	ctrl7 only outputs k values once the controller is first moved. To set an initial k-value, a call to initc7 is required. Ctrlinit does not work for this purpose.

Credits

Author: Gabriel Maldonado

Italy

New in Csound version 3.47

Thanks goes to Rasmus Ekman for pointing out the correct MIDI channel and controller number ranges.

The a-rate version of ctrl7 was added in version 5.06

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