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Functional description, Input receiver, Fpga delay section – Grass Valley 8916 User Manual

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8916 Instruction Manual

8916 AES/EBU Auto-Tracking Delay DA

Functional Description

Refer to the block diagram in

Figure 10

while reading the following func-

tional description.

Figure 10. 8916 Block Diagram

Input Receiver

AES/EBU audio data is fed into the 8916 through an isolation transformer
where it is received by the receiver chip. The receiver recovers the clock and
synchronization signals, and demultiplexes the audio and digital data.

FPGA Delay Section

The delay section receives the 12.29 MHz clock, synchronization informa-
tion, frequency information, and error status information. It also receives
the switch position settings that determine the fixed length of delay.

Loop-through

Delay Control I/F

To Host

Fine

Coarse

Delay Select Switches

RS 232

AES/EBU Input

RX+

RX–

Serial Data

SCK

F Sync

Error

Freq.

Serial Data

SCK

Parallel Data

Parallel Data

FIFO

Control

CBL

V

U

C

MCK

F Sync

AES/EBU

Serial

Data

Outputs

32 kHz

44.1 kHz

48 kHz

Tracking

Remote Override

Power

Comm

Fault

Conf

Receiver/

De-MUX

Field

Programmable

Gate Array

(FPGA)

Controller

Line

Drivers

MUX