5-42
Cisco ATA 186 and Cisco ATA 188 Analog Telephone Adaptor Administrator’s Guide (H.323)
OL-4008-01
Chapter5 Parameters and Defaults
Optional Feature Parameters
•off-time controls the length of time between audible tones in milliseconds (ms) expressed as an
integer from 0 to 0xffff sample at 8000 samples/second.
•total-tone-time controls the length of time the tone is audible (0 to 0xffff). If this value is set to 0,
the tone will play until another call event stops the tone. For DialTone, Bus yTone, ReorderTone, and
RingBackTone, the configurable value is the number of 10 ms (100 = 1 sec ond) units.
For the other tones, the value is the number of samples at 8000 samples/second, where the following
information applies:
–
Frequency ranges from 0 to 4000 (Hz)
–
Transformed Frequency = 32767 · cos (2pi·Frequency/8000)
–
Amplitude ranges from 0 to 32767
–
Transformed Amplitude = A · 32767 · sin (2pi·Frequency/8000)
The scaling factor A determines the volume level of the tone. To calculate scaling factors, see the
“How to Calculate Scaling Factors” section on page5-42.
Note All tones are persistent (until the CiscoATA changes state) except for the call-waiting tone and the
confirm tone. The call-waiting tone, however, repeats automatically once every 10 seconds while the
call-waiting condition exists.
How to Calculate Scaling Factors
Use the following formula to calculate the scaling factor A:
A=0.5 * 10^((k+10-(n-1)*3)/20)
In this formula, k is the desirable volume in dBm; n is the number of frequency components. The ^
symbol means to the order of.
Example
If a one-frequency component of -20 dBm volume level is desirable, the n:
A=0.5 * 10^((-20+10)/20) = 0.16
Recommended Values
The following settings are recommended for the US:
•DialTone = "2,31538,30831,3100,3885,1,0,0,1000" (approximately -10 dBm)
•BusyTone = "2,30467,28959,1191,1513,0,4000,4000,0" (approximately -21 dBm)
•ReorderTone = "2,30467,28959,1191,1513,0,2000,2000,0" (approximately -21 dBm)
•RingBackTone = "2,30831,30467,1943,2111,0,16000,32000,0" (approximately -16 dBm)
•CallWaitTone = "1,30831,0,5493,0,0,2400,2400,4800" (approximately -10 dBm)
•AlertTone = "1,30467,0,5970,0,0,480,480,1920" (approximately -10 dBm)