S/PDIF—Sony/Philips Digital Interface
Symphony DSP56724/DSP56725 Multi-Core Audio Processors, Rev. 0
Freescale Semiconductor
18-21
18.3.5
S/PDIF Receiver Interrupt Exception Definition
There are several S/PDIF exceptions that will trigger an interrupt. See
Table 18-22. S/PDIF Receiver Interrupt Exceptions
S/PDIF Exception
Description
RcvChannelNew
Set when the SPDIFRcvCChannel_h and SPDIFRcvCCHannel_l registers are updated. The
SPDIFRcvCChannel_h and SPDIFRcvCCHannel_l registers are updated for every new C-Channel
received. The Control Status channel change exception is reset on a write to the InterruptClear register.
RcvIllegalSymbol
Set on reception of an illegal symbol during S/PDIF receive. Reset by writing to the InterruptClear
register.
1
1
The S/PDIF input is a biphase/mark modulated signal. The time between any two successive transitions of the S/PDIF signal
is always 1, 2 or 3 S/PDIF symbol periods long. The S/PDIF receiver will parse the stream, and split it in so-called symbols. It
recognizes s1, s2 and s3 symbols, depending on the length of the symbols. Not all sequences of these symbols are allowed.
For example, a sequence s2-s1-s1-s1-s2 cannot occur in a no-error S/PDIF signal. If the receiver finds such an illegal
sequence, the illegal symbol interrupt is set. No corrective action is undertaken. When the interrupt occurs, this means that
(a) The S/PDIF signal is destroyed by noise.
(b) The S/PDIF frequency changed.
RcvParityError
Set on reception of bit error. (Parity bit does not match). Reset on write to the InterruptClear register.
Rcv FIFO Full
Set when the S/PDIF receive data FIFO is full.
Rx Over/Under
Set when there is an overrun/underrun on the S/PDIF receive data FIFO.
Rx Resync
Set when a resynchronization event occurs on the S/PDIF receive data FIFO.
RxUChannelFull
Set when the next 24 bits of U channel code are available.
RxQChannelOver
Set when the Q channel buffer is overrun.
RxUChannelOver
Set when the U channel buffer is overrun.
RxQChannelFull
Set when the next 24 bits of Q channel code are available.
RxUQSyncFound
Set when the UQ channel sync is found.
RxUQFrameError
Set when a UQ frame error is found.