Cs8420 – Cirrus Logic CS8420 User Manual

Page 58

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DS245F4

CS8420

RERR - Receiver Error Indicator

When high, indicates a problem with the operation of the AES3 receiver. The status of this pin is updated once per
sub-frame of incoming AES3 data. Conditions that cause RERR to go high are: parity error, and bi-phase coding
error, as well as loss of lock in the PLL. This is also a start-up option pin, and requires a pull-up or pull-down resistor.

EMPH/U - Pre-Emphasis Indicator Output or U-Bit Data Input

The EMPH/U pin reflects either the state of the EMPH channel status bits in the incoming AES3 type data stream,
or is the serial U-bit input for the AES3 type transmitted data, clocked by OLRCK. When indicating emphasis,
EMPH/U is low if the incoming data indicates 50/15

μs pre-emphasis and high otherwise.

COPY - Copy Channel Status Bit Output

The COPY pin reflects the state of the COPY Channel Status bit in the incoming AES3 type data stream. This is
also a start-up option pin, and requires a pull-up or pull-down resistor.

ORIG - Original Channel Status Output

SCMS generation indicator. This is decoded from the incoming category code and the L bit. A low output indicates
that the audio data stream is 1st generation or higher. A high indicates that the audio data stream is original.

PRO/C - Professional Channel Status Bit Output or C-Bit Data Input

The PRO/C pin either reflects the state of the Professional/Consumer Channel Status bit in the incoming AES3 type
data stream, or is the serial C-bit input for the AES3 type transmitted data, clocked by OLRCK.

AUDIO/V - Audio Channel Status Bit Output or V-Bit Data Input

The AUDIO/V pin either reflects the state of the audio/non audio Channel Status bit in the incoming AES3 type data
stream, or is the V-bit data input for the AES3 type transmitted data stream, clocked by OLRCK.

Audio Output Interface:

SDOUT - Serial Audio Output Port Data Output

Audio data serial output pin. This is also a start-up option pin, and requires a pull-up or pull-down resistor.

OSCLK - Serial Audio Output Port Bit Clock Input or Output

Serial bit clock for audio data on the SDOUT pin.

OLRCK - Serial Audio Output Port Left/Right Clock Input or Output

Word rate clock for the audio data on the SDOUT pin. The frequency will be at the output sample rate (Fso)

AES3/SPDIF Transmitter Interface:

TCBL - Transmit Channel Status Block Start

When operated as output, TCBL is high during the first sub-frame of a transmitted channel status block, and low at
all other times. When operated as input, driving TCBL high for at least three OMCK clocks will cause the current
transmitted sub-frame to be the start of a channel status block.

TCBLD - Transmit Channel Status Block Direction Input

Connect TCBLD to VD+ to set TCBL as an output. Connect TCBLD to DGND to set TCBL as an input.

TXN, TXP - Differential Line Driver Outputs

Differential line driver outputs, transmitting AES3 type data. Drivers are pulled to low while the CS8420 is in the reset
state.

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