img-spdif-in.rst 1.9 KB

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  1. ================================================
  2. Imagination Technologies SPDIF Input Controllers
  3. ================================================
  4. The Imagination Technologies SPDIF Input controller contains the following
  5. controls:
  6. * name='IEC958 Capture Mask',index=0
  7. This control returns a mask that shows which of the IEC958 status bits
  8. can be read using the 'IEC958 Capture Default' control.
  9. * name='IEC958 Capture Default',index=0
  10. This control returns the status bits contained within the SPDIF stream that
  11. is being received. The 'IEC958 Capture Mask' shows which bits can be read
  12. from this control.
  13. * name='SPDIF In Multi Frequency Acquire',index=0
  14. * name='SPDIF In Multi Frequency Acquire',index=1
  15. * name='SPDIF In Multi Frequency Acquire',index=2
  16. * name='SPDIF In Multi Frequency Acquire',index=3
  17. This control is used to attempt acquisition of up to four different sample
  18. rates. The active rate can be obtained by reading the 'SPDIF In Lock Frequency'
  19. control.
  20. When the value of this control is set to {0,0,0,0}, the rate given to hw_params
  21. will determine the single rate the block will capture. Else, the rate given to
  22. hw_params will be ignored, and the block will attempt capture for each of the
  23. four sample rates set here.
  24. If less than four rates are required, the same rate can be specified more than
  25. once
  26. * name='SPDIF In Lock Frequency',index=0
  27. This control returns the active capture rate, or 0 if a lock has not been
  28. acquired
  29. * name='SPDIF In Lock TRK',index=0
  30. This control is used to modify the locking/jitter rejection characteristics
  31. of the block. Larger values increase the locking range, but reduce jitter
  32. rejection.
  33. * name='SPDIF In Lock Acquire Threshold',index=0
  34. This control is used to change the threshold at which a lock is acquired.
  35. * name='SPDIF In Lock Release Threshold',index=0
  36. This control is used to change the threshold at which a lock is released.