5-43
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
Tone Parameter Syntax—Extended Formats
Two types of extended format exist for the Cisco ATA tone parameters:
•
Extended Format A, page 5-43
—This format can be used for the following tone parameters:
–
DialTone
–
BusyTone
–
RingbackTone
–
CallWaitTone
–
AlertTone
•
Extended Format B, page 5-44
—This format can be used only for the ReorderTone parameter.
Extended Format A
Each tone is specified by 11 integers, as follows:
parametername
:
NumOfFreqs,Tfreq1,Tamp1,Tfreq2,Tamp2,NumOfOnOffPairs,OnTime1,
OffTime1,OnTime2,OffTime2,TotalToneTime
•
parametername
is the name of the tone.
•
NumOfFreqs
=
100 + the number of frequencies in the tone. (Therefore,
NumOfFreqs
= 101 for one
frequency, and 102 for two frequencies.)
•
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 formula:
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
.
•
NumOfOnOffPairs
is
the number of on-off pairs in the cadence of the tone.
Valid values are 0, 1 and 2. Use 0 if the tone is steady.
•
OnTime1
and
OnTime2
values
are the lengths of time the tone is played for the first and second
on-off pairs of a cadence, respectively. (See
Figure 5-1
for a graphical representation.)
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.
