RFX144V24-S23 and RFX96V24-S23 Modem Designer’s Guide
1070
4-7
No. 6a
IIA Tone 1 Frequency
No. 6b XIA Tone 1 Frequency
No. 8a
IIA Tone 2 Frequency
No. 8b XIA Tone 2 Frequency
Format:
16 bits, unsigned
Equation:
N = 6.8267 x Frequency (in Hz) for 9600 Hz sampling rate
N = 8.192 x Frequency (in Hz) for 8000 Hz sampling rate
Convert N to hexadecimal then store in RAM.
No. 7a
IIA Tone 1 Transmit Output Level
No. 7b XIA Tone 1 Transmit Output Level
No. 9a
IIA Tone 2 Transmit Output Level
No. 9b XIA Tone 2 Transmit Output Level
Format:
16-bits, positive, twos complement
Calculate the transmit output level (power) of each tone independently by using the equation for Transmit Output Level (No.
10).
Total power transmitted in tone configuration is the result of both tone 1 power and tone 2 power.
No. 10
Transmit Output Level (Ps)
Format:
16-bits, positive, twos complement
Equation:
Transmit Output Level (Ps) = 18426 [10(Po/20)]
Where:
Po = output power in dBm with a 600 ohm load termination.
Ps = output power in dBm with a series 600 ohm resistor into a 600 ohm load (Ps = Po - 6).
Convert Transmit Output Level to hexadecimal and store in RAM.
Default Value:
7FFFh
Note: For the modem interface circuits shown in Figure 14-1, the maximum transmit output level (Ps) is -1 dBm at TXA.
No. 11
Equalizer Tap Coefficients
Access codes 50h through 7Fh represent 48 complex taps.
The equalizer tap coefficients can be useful for restoring modem operation after loss of equalization without requesting a
training sequence from the transmitter. Since the equalizer tap coefficients are complex numbers, they require two write
operations per tap, one for the real part and one for the imaginary part. When writing the imaginary part, the access codes
50h through 7Fh must be changed to D0h through FFh. When writing the real part, or when reading the complex number,
the access codes 50h through 7Fh are correct.
Format:
16 bits, signed, twos complement, real
16 bits, signed, twos complement, imaginary
No. 12
Rotated Equalizer Output (Eye Pattern)
No. 13
Decision Points (Ideal)
Format:
16 bits, signed, twos complement, real
16 bits, signed, twos complement, imaginary
Summary of Contents for RFX144V24-S23
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