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Is it possible to use SPDIF in "slave" clock mode on the SC587 ?

Category: Hardware
Product Number: SC587

The silicon anomaly list for the SC587 describes an anomaly with the SPDIF receiver : 

73. 20000094 - SPDIF Receiver Output Clock Is Unreliable:
DESCRIPTION:
When operating properly, the SPDIF receiver output clock (SPDIF_RX_TDMCLK_O) frequency is 256 times the sampling rate. The SPDIF
receiver, however, fails to maintain this relationship; thus, the SPDIF_RX_TDMCLK_O output clock is unreliable.

WORKAROUND:
Do not use the SPDIF_RX_TDMCLK_O output clock.

APPLIES TO REVISION(S):
1.0, 1.2

Does that mean I effectively can't use the SPDIF to receive a signal from an externally clocked device ? Ie recovering a clock from the SPDIF Rx stream ?

Parents
  • I suspect the answer is : you have to use an ASRC like shown in the spdif_playback example project ? 

                 _____________                  _____________                  _____________
                |             |---Data0------->|             |---Data0------->|             |
                |             |---Clk--------->|   ASRC0     |<--Clk---x----->|             |
     DAI019---->|             |---Fs---------->|_____________|<--Fs----|--x-->|             |
                |  Rx SPDIF   |                                        |  |   |    SPORT    |
                |             |                                        |  |   |     0a      |
                |             |                                        |  |   |             |
                |_____________|                                        |  |   |_____________|
                                               _____________           |  |         |
                                  DAI103      |   3.072 MHz |----------x  |         |
                                25.476MHz -x->|PCGA   48kHz |-------------x     Mem Copy
                                              |_____________|                       |
                                                                                    |   
                                                _____________                  _____v_______
                                               |             |<--Data0--------|             |
                                               |             |---Clk--------->|             |
                                               |             |---Fs---------->|             |
                                               |  AD1962a    |                |    SPORT    |
                                               |    DAC      |                |     4b      |
                                               |             |                |             |
                                               |_____________|                |_____________|
    

Reply
  • I suspect the answer is : you have to use an ASRC like shown in the spdif_playback example project ? 

                 _____________                  _____________                  _____________
                |             |---Data0------->|             |---Data0------->|             |
                |             |---Clk--------->|   ASRC0     |<--Clk---x----->|             |
     DAI019---->|             |---Fs---------->|_____________|<--Fs----|--x-->|             |
                |  Rx SPDIF   |                                        |  |   |    SPORT    |
                |             |                                        |  |   |     0a      |
                |             |                                        |  |   |             |
                |_____________|                                        |  |   |_____________|
                                               _____________           |  |         |
                                  DAI103      |   3.072 MHz |----------x  |         |
                                25.476MHz -x->|PCGA   48kHz |-------------x     Mem Copy
                                              |_____________|                       |
                                                                                    |   
                                                _____________                  _____v_______
                                               |             |<--Data0--------|             |
                                               |             |---Clk--------->|             |
                                               |             |---Fs---------->|             |
                                               |  AD1962a    |                |    SPORT    |
                                               |    DAC      |                |     4b      |
                                               |             |                |             |
                                               |_____________|                |_____________|
    

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