AD1985 Analog Devices, AD1985 Datasheet - Page 32

• Manufacturer Part Number: AD1985
• Description: AC'97 2.3 Soundmax Codec W/jack Sensing
• Manufacturer: Analog Devices

AD1985
SPDIF Control Register (Index 0x3A)
Reg.Num.
0x3A
Register 0x3A is a read/write register that controls SPDIF
functionality and manages bit fields propagated as channel
status (or subframe in the V case). With the exception of V, this
register should only be written to when the SPDIF transmitter is
PRO
AUD
COPY
PRE
CC[6:0]
L
SPSR[1:0]
V
Name
SPDIF Control
Professional. 1 indicates professional use of channel status, 0 indicates consumer.
Non-Audio. 1 indicates data is non-PCM format, 0 indicates data is PCM.
Copyright. 1 indicates copyright is asserted, 0 indicates copyright is not asserted.
Pre-emphasis. 1 indicates filter pre-emphasis is 50/15 µs, 0 indicates no pre-emphasis.
Category Code. Programmed according to IEC standards, or as appropriate.
Generation Level. Programmed according to IEC standards, or as appropriate.
SPDIF transmit Sample Rate.
SPSR[1:0] = 00: Transmit Sample Rate = 44.1 kHz.
SPSR[1:0] = 01: Reserved.
SPSR[1:0] = 10: Transmit Sample Rate = 48 kHz (default).
SPSR[1:0] = 11: Not supported.
Validity. This bit affects the “Validity” flag, (Bit <28> transmitted in each SPDIF L/R subframe) and enables
the SPDIF transmitter to maintain connection during error or mute conditions.
V = 1: Each SPDIF subframe (L+R) has Bit <28> set to 1. This tags both samples as invalid.
V = 0: Each SPDIF subframe (L+R) has Bit <28> set to 0 for valid data and 1 for invalid data (error condition).
Note that when V = 0, asserting the VFORCE bit (D15) in Register 0x2A (Extended Audio Stat/Ctrl) will force
the “Validity” flag low, marking both samples as valid.
D15 D14 D13
V
X
SPSR1 SPSR0 L
D12
D11 D10 D9
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CC6 CC5 CC4 CC3 CC2 CC1 CC0 PRE COPY AUD PRO 0x2000
disabled (SPDIF bit in Register 0x2A is 0). This ensures that
control and status information initialize correctly at the
beginning of SPDIF transmission.
D8
D7
D6
D5
D4
D3 D2
D1
D0
Default