Cisco Systems ATA 188 Telephone Accessories User Manual


 
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Cisco ATA 186 and Cisco ATA 188 Analog Telephone Adaptor Administrator’s Guide for H.323 (version 3.0)
OL-4804-01
Chapter 5 Parameters and Defaults
Tone Configuration Parameters
NumOfFreqs is the number of frequency components (0, 1 or 2).
Tfreq1 and Tfreq2 are the transformed frequencies of the first and second frequencies, respectively.
Their values are calculated with the following formula:
32767 * cos (2*pi*F/8000)
where F is the desired frequency in Hz. Set this value to 0 if the frequency does not exist.
The range of each value is –32768 to 32767.
For negative values, use the 16-bit 2’s complement value. For example, enter –1 as 65535 or as
0xffff.
Tamp1 and Tamp2 are the transformed amplitudes of the first and second frequencies, respectively.
Their values are calculated with the following formulas:
32767 * A * sin(2*pi*F/8000)
A (amplitude factor) = 0.5 * 10^((k+10-(n-1)*3)/20)
where F is the desired frequency in Hz, k is the desired volume in dBm, and n is the number of
frequencies. The ^ symbol means to the order of.
Steady controls whether the tone is constant or intermittent. A value of 1 indicates a steady tone and
causes the Cisco ATA to ignore the on-time and off-time parameters. A value of 0 indicates an on/off
tone pattern and causes the Cisco ATA to use the on-time and off-time parameters.
OnTime controls the length of time the tone is played in milliseconds (ms).
Specify each value as a number of samples with a sampling rate of 8 kHz. The range of each value
is 0 to 0xffff. For example, for a length of 0.3 seconds, set the value to 2400.
OffTime controls the length of time between audible tones in milliseconds (ms).
Specify each value as a number of samples with a sampling rate of 8 kHz. The range of each value
is 0 to 0xffff. For example, for a length of 0.3 seconds, set the value to 2400.
TotalToneTime controls the length of time the tone is played. If this value is set to 0, the tone will play
until another call event stops the tone. For DialTone, DialTone2, BusyTone, ReorderTone, and
RingBackTone, the configurable value is the number of 10 ms (100 = 1 second) units.
For the remaining tones, the configurable value is the number of samples with a sampling rate of 8
kHz.
Note All tones are persistent (until the Cisco ATA 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.