MT9092
Tone Coeff Register 1-DTMF or Tone Ringer
ADDRESS = 23h WRITE/READ VERIFY
Power Reset Value
0000 0000
B7
7
B6
6
B5
5
B4
4
B3
3
B2
2
B1
1
B0
0
This register is used to program the low-group frequency of the DTMF program. The tone coefficient is calculated as follows:
COEF = 0.128 x Frequency
where: Frequency is in Hz (note: COEF must be converted to an 8 bit binary integer)
Highest frequency possible:
Lowest frequency possible:
Frequency resolution:
Pre-twist:
1992.2 Hz
7.8 Hz
7.8 Hz
-2.1dB ± 0.2dB
This register is used to program the first frequency of the squarewave ringer program. The tone coefficient is calculated as follows:
COEF = 8000 / Frequency
where: Frequency is in Hz (note: COEF must be rounded off and converted to an 8 bit binary integer)
Highest frequency possible:
Lowest frequency possible:
Frequency resolution:
4000 Hz
31.4 Hz
non-linear
Tone Coeff Register 2-DTMF or Tone Ringer
ADDRESS = 24h WRITE/READ VERIFY
Power Reset Value
0000 0000
B7
7
B6
6
B5
5
B4
4
B3
3
B2
2
B1
1
B0
0
This register is used to program the high-group frequency of the DTMF program. The tone coefficient is calculated as follows:
COEF = 0.128 x Frequency
where: Frequency is in Hz (note: COEF must be converted to an 8 bit binary integer)
Highest frequency possible:
Lowest frequency possible:
Frequency resolution:
Pre-twist:
1992.2 Hz
7.8 Hz
7.8 Hz
0dB
This register is used to program the second frequency of the squarewave program. The tone coefficient is calculated similarly to tone
ADDRESS 25h is RESERVED
Tone Ringer Warble Rate-Tone Ringer
ADDRESS = 26h WRITE/READ VERIFY
Power Reset Value
0000 0000
B7
7
B6
6
B5
5
B4
4
B3
3
B2
2
B1
1
B0
0
The tone ringer will switch between squarewave frequencies at a warble frequency defined by this register. The relationship between
the duration period of each tone and the 8 bit warble coefficient is as follows:
Tone duration (warble frequency) = 500 / COEF
where: Frequency is in Hz, and 0≤COEF <256
Highest frequency possible:
Lowest frequency possible:
500 Hz
2.0 Hz
Addresses: 27h to 2Dh are transmit and receive gains and coefficients used by the filters in the handsfree
decision circuit.
2Eh to 3Fh are scratch-pad ram locations used by the DSP algorithms as temporary storage dur-
ing calculations.
7-31
MITEL [ MITEL NETWORKS CORPORATION ]
