dddvb/docs/iq_samples

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~The Max SX8 can provide IQ samples in real time.
They are 8 bit signed values embedded in TS packets with PID 0x200.
API:
Currently DTV_STREAM_ID is misused.
0x10000000 - symbols (locked and tracked) at symbol rate
0x20000000 - samples at symbol rate
(fixed at ADC rate (1550/24=64.583... MHz) if 0x00010000 is set)
Max. sample rate is 64.583333 MHz.
0x00xx0000 - flags
Bit 0 : 0 = VTM/SDR, 1 = SCAN,
Bit 1: 1 = Disable channel AGC,
Bit 2: 1 = Set Gain.
0x0000xx00 - xx=gain
0x000000xx - xx=flags
Bit 0:1 Preamp Mode; 0 = Preamp AGC, 1 == Minimum (~ -17dB) ,
2 = Medium, 3 = Maximum gain {~ 15dB}
Bit 2: Bypass Input LNA (6 dB less gain) (Note this is after Preamp)
Bit 4: Set RF Gain
Bit 5: Freeze RF Gain (Turn AGC off at current gain, only when already enabled)
Bit 7: Optimize RF Gain and freeze for FFT