Semtech EB-GS2971, Руководство пользователя

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EB-GS2971
Evaluation Board User Guide
52169 - 2
June 2012
6 of 22
Proprietary & Confidential
1.2 SDI Input (J4)
The EB-GS2971 includes a single SDI input.
1.3 Switch Settings (SW2)
A DIP switch (SW2) is populated on the EB-GS2971, with each bit labelled on the
silk-screen. This switch is used to set the operating modes of the GS2971. The signal can
be set HIGH by placing the switch to the ‘1’ position (Closed).
NOTE:
Some signals are active LOW, so you will need to switch the bit ‘OFF’ to activate
the signal.
Refer to Table 1-1 below for definitions of each bit.
Table 1-1: SW2 Settings
Bit Name Description
TIM8 6 1 C onnected to the GS 2971 TIM_8 6 1 pin. Used to select C EA-8 6 1 timing mode.
When TIM_8 6 1 is HI G H, the device outputs C EA 8 6 1 timing signals (H S YN C /V S YN C /DE) instead of H:V:F digital
timing signals.
S MPTE_BYPA SS b C onnected to the GS 2971 S MPTE_BYPA SS pin. Used to enable/disable all forms of encoding/decoding,
descrambling, audio and AN C data detection and extraction and error detection and correction.
When the AUTO/MAN bit in the Host Interface register is HI G H (Default), this pin is an OUTPUT. S MPTE_BYPA SS is
HI G H when the device locks to a S MPTE compliant input. S MPTE_BYPA SS is LOW under all other conditions.
When the AUTO/MAN bit in the Host Interface register is LOW, this pin is an INPUT. No S MPTE scrambling takes
place, and none of the I/O processing features of the device are available when S MPTE_BYPA SS is set LOW.
When S MPTE_BYPA SS is set HI G H, the device carries out S MPTE descrambling and I/O processing.
When S MPTE_BYPA SS and DVB_A S I are both set LOW, the device operates in Data-Through mode.
DVB_A S I C onnected to the GS 2971 DVB_A S I pin. Used to enable/disable DVB-A S I data decoding in manual mode.
When the AUTO/MAN bit in the Host Interface is LOW, this pin is an input and when set HI G H the device will
carry out DVB_A S I data extraction and processing. The S MPTE_BYPA SS pin must be set LOW.
When S MPTE_BYPA SS and DVB_A S I are both set LOW, the device operates in Data-Through mode.
When the AUTO/MAN bit in the Host Interface is HI G H (Default), DVB-A S I input is not supported.
AUDIO_EN/DI S b C onnected to the GS 2971 AUDIO_EN/DI S pin. Enables or disables audio extraction.
IOPRO C _EN/DI S b C onnected to the GS 2971 IOPRO C _EN/DI S pin. Used to enable or disable I/O processing features.
When IOPRO C _EN/DI S is HI G H, the I/O processing features of the device are enabled.
When IOPRO C _EN/DI S is LOW, the I/O processing features of the device are disabled, and the latency of the
device is LOW. Please refer to the Data S heet for more information.
20BIT/10BITb C onnected to the GS 2971 20bit/10bit pin. Used to select the output bus width. (HI G H = 20bit, LOW = 10bit)
S DO_EN/DI S b C onnected to the GS 2971 S DO_EN/DI S pin. Used to enable/disable the serial digital output stage.
When the S DO_EN/DI S is LOW, the serial digital output signals, S DO and S DO, remain static.
When connected to logic HI G H, the serial digital output signals, S DO and S DO, are enabled.
The S DO and S DO outputs will also be disabled when the RE S ET pin is LOW.
R C _BYPb C onnected to the GS 2971 R C _BYP pin. When this pin is LOW, the serial digital output is the buffered version of
the input serial data.
When this pin is HI G H, the serial digital output is the reclocked version of the input serial data.