wm9714l Wolfson Microelectronics plc, wm9714l Datasheet - Page 62

• Manufacturer Part Number: wm9714l
• Description: Ac?97 Audio Codec
• Manufacturer: Wolfson Microelectronics plc

WM9714L
DIGITAL AUDIO (S/PDIF) OUTPUT
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The WM9714L supports the S/PDIF standard. Pins 48 & 12 can be used to output the S/PDIF data.
Note that pins 48 & 12 can also be used as GPIO pins. The GE5 & GE8 bits (register 56h, bit 5 & bit
8) select between GPIO and S/PDIF functionality for pins 48 & 12 respectively (see “GPIO and
Interrupt control” section).
Register 3Ah is a read/write register that controls S/PDIF functionality and manages bit fields
propagated as channel status (or sub-frame in the V case). With the exception of V, this register
should only be written to when the S/PDIF transmitter is disabled (S/PDIF bit in register 2Ah is ‘0’).
Once the desired values have been written to this register, the contents should be read back to
ensure that the sample rate in particular is supported, then S/PDIF validity bit SPCV in register 2Ah
should be read to ensure the desired configuration is valid. Only then should the S/PDIF enable bit in
register 2Ah be set. This ensures that control and status information start up correctly at the
beginning of S/PDIF transmission.
PP, Rev 3.2, October 2008
Pre-Production
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