STV8247_06 Datasheet, PDF (69/156 Pages) STMicroelectronics – Digital Audio Decoder/Processor for A2 and NICAM Television/Video Recorders

STV82x7
Register List
Bit Name
AGC_ERR[4:0]
SIG_OVER
SIG_UNDER
Reset
Function
00000
Amplifier Gain Control
This is the Gain Control value of AGC. There are 20 steps of +1.5 dB (see Note below).
00000: Gain-min
10100: Gain-min + 30 db
11111: Gain-min + 30 db
0 AGC Input SIgnal Upper Threshold
0: Normal signal
1: Signal too large and AGC is overloaded
0 AGC Input SIgnal Lower Threshold
0: Normal signal
1: Signal too small and AGC is underloaded
When the AGC is in Automatic mode (AGC_CMD = 0), bits SIG_OVER and SIG_UNDER indicate
if the input signal is too small/large and the AGC is under/overloaded. This is useful when setting
the STV82x7 SIF input level.
Note:
When AGC_CMD = 0, AGC_ERR[4:0] can be read -- indicating the input level. It can also be written
to -- presetting the AGC level which will then adjust itself to the final value.
When AGC_CMD = 1, the AGC is off and writing to AGC_ERR[4:0] directly controls the AGC
amplifier gain. Reading AGC_ERR just confirms the fixed value.
DC_ERR_IF
DC Offset Status for IF ADC
Address: 10h
Type: R
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
DC_ERR[7:0]
Bit 2
Bit 1
Bit 0
Bit Name
DC_ERR[7:0]
Reset
00000000 DC offset error of IF ADC output
Function
12.5 Demodulator Channel 1
CARFQ1H, CARFQ1M, CARFQ1L Channel 1 Carrier DCO Frequency
Address: 12h to 14h
Type: R/W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
CARFQ1[23:16], CARFQ1[15:8], CARFQ1[7:0]
Bit 1
Bit 0
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