Rockwell RFX144V24-S23, Руководство дизайнера

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RFX144V24-S23 and RFX96V24-S23 Modem Designer’s Guide
4-10 1070
No. 30 Minimum Off-Time (DTMF)
The minimum off-time is defined as the minimum period of time of the DTMF signal beginning when the energy falls below
the turn-off threshold and ending when a gain hit is detected. The off-time parameter is equal to the desired minimum off-
time minus the drop out time. The default off-time is set for 40.0 ± 1 ms with a default drop out time parameter of 5.0 ms. To
increase or decrease the off-time parameter value, convert the increase/decrease into hex and add/subtract to/from the
current value. (See Section 13.3.)
Format: 16-bits, positive, twos complement
Equation: Minimum Off-Time ± [(Increase/Decrease in ms)9.6]h (drop out time equal to 5.0 ms).
Range: 0 to 7FFFh
Default Value: 013Eh (CONF = 21h); 010Fh (CONF = 90h, 92h, 94h or 98h)
No. 31 Minimum Cycle-Time (DTMF)
The minimum cycle-time is defined as the minimum period of the DTMF signal beginning when the signal is detected and
ending when the next signal begins. The cycle-time parameter is equal to the desired minimum cycle-time minus the drop
out time. The default cycle-time parameter is set for 93.0 ±1 ms with a default drop out time parameter of 5.0 ms. To
increase or decrease the cycle-time parameter value, convert the increase/decrease into hex and add/subtract to/from the
current value. (See Section 13.3.)
Format: 16-bits, positive, twos complement
Equation: Minimum Cycle-Time ± [(Increase/Decrease in ms)9.6]h (dropout time equal to 5.0 ms).
Range: 0 to 7FFFh
Default Value: 022Ah (CONF = 21h); 01C7h (CONF = 90h, 92h, 94h or 98h)
No. 32 Minimum Dropout-Time (DTMF)
The minimum dropout time is defined as the maximum period of the DTMF signal beginning when the signal energy drops
below the turn-off threshold and ending when the signal energy returns that is considered to be part of the on-time. The
default dropout-time parameter is set to 5.0 ms. (See Section 13.3.)
Format: 16-bits, positive, twos complement
Equation: [(Desired Time in ms)9.6]h
Range: 0 to 7FFFh
Default Value: 0029h (CONF = 21h); 0022h (CONF = 90h, 92h, 94h or 98h)
No. 33 Maximum Speech Energy (DTMF)
This parameter specifies the maximum relative speech energy that may be detected and still receive DTMF signals. The
speech energy is measured in the frequency region of second or third harmonics of the DTMF tones. To disable the speech
energy detector, set this parameter to its full scale positive value 7FFFh. Decreasing the value of this parameter may
degrade signal-to-noise ratio (SNR) performance, but may reduce false settings of status bit EDET due to speech signals.
To increase or decrease the maximum speech energy parameter value, convert the increase/decrease into hex and
add/subtract to/from the current value. (See Section 13.3.)
Format: 16-bits, positive, twos complement
Equation: Maximum Speech Energy ± (Increase/Decrease)h
Range: 0 to 7FFFh
Default Value: 0519h (CONF = 21h); not available (CONF = 90h, 92h, 94h or 98h)
No. 34 Frequency Deviation, Low Group (DTMF)
This parameter controls the acceptable frequency range for the low group DTMF tones. Increasing the value of this
parameter increases the frequency range. The frequency range will vary from one DTMF symbol to another. To increase or
decrease the parameter value, convert the increase/decrease into hex and add/subtract to/from the current value. (See
Section 13.3.)
Format: 16-bits, positive, twos complement
Equation: Frequency Deviation ±(Increase/Decrease)h
Range: 0 to 7FFFh
Default Value: 034Ah (CONF = 21h); 0288h (CONF = 90h, 92h, 94h or 98h)