Suggestion for USB/PCI-E DVB-C tuner? (1 Viewer)

FreakyJ

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    Yes
     

    FreakyJ

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    As far as I know all the Problems are fixed in the mp1 patch. I can decrypt more than one channel with my tbs card. ... Also multiple ci Slots are now supported and also the latest cards with ci slot. I ported your device detection from tve 3.5 ;) and we updated the tbsciapi.dll
     

    mm1352000

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    All I can say is that from the code perspective I'm pretty sure the problems are not intentionally fixed.

    I can decrypt more than one channel with my tbs card.
    This could be CAM-dependent behaviour.

    Also multiple ci Slots are now supported and also the latest cards with ci slot. I ported your device detection from tve 3.5
    Yep, this I agree with. :)

    and we updated the tbsciapi.dll
    Yep, and that solves the crashing problem. :)

    Only the problems 3 and 4 are not fixed AFAIK. I still see reports that when you start timeshifting with one tuner and a recording starts later in the background, the timeshifting is cut off (problem 4). This can be worked around by enabling preloading. It is properly solved in TVE 3.5.
     

    FreakyJ

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    First of all thank you for your answer :)

    But I still don't understand it correctly, so please for give me...

    Problem 3 is:
    3. No support for multi-channel decryption.
    But as stated here it works:
    I can decrypt more than one channel with my tbs card.
    This could be CAM-dependent behaviour.
    Or do I misunderstand this? Sorry, I really want to understand this :/

    Never read about problem 4 in the last time oO Also no reports in the big TBS thread...
     

    mm1352000

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    But I still don't understand it correctly, so please for give me...
    No problem, happy to explain. :)

    So, when we want a CAM to decrypt one or more channels we must send it CAPMT (conditional access program map table). Two of the important parameters in that PMT (aside from the program number AKA service ID and elementary stream details) are the list action and the command.
    List action = only (for decrypting only one channel) or first, more, last, add and update (for decrypting multiple channels)
    Command = ok descrambling (to decrypt), ok MMI, query (ask the CAM whether it can decrypt), or remove (stop decrypting)

    You can see this in the TVE 3.5 code here:
    https://github.com/MediaPortal/Medi...ibrary.Interfaces/DvbConditionalAccess.cs#L37
    https://github.com/MediaPortal/Medi...rary.Interfaces/DvbConditionalAccess.cs#L2232

    The TvCardBase code chooses the right list management action:
    https://github.com/MediaPortal/Medi.../TVLibrary/Implementations/TvCardBase.cs#L961

    ...and the TBS plugin passes the values through to the CAM:
    https://github.com/MediaPortal/Medi.../CustomDevices/Turbosight/Turbosight.cs#L1411

    Ignore the fact that the TBS interface doesn't actually use "proper" format CA PMT. CA PMT matching the EN 50221 format will be constructed inside tbsCIapi.dll before sending it to the CAM. Other interfaces directly accept the EN 50221 CA PMT.

    Anyhow, what I'm saying is that AFAIK the current patch always sends "CA PMT" with list management action "only". You can see this in the patch that was posted here:
    https://forum.team-mediaportal.com/...ther-improvements.103276/page-47#post-1047027
    Code:
      if (_turbosight != null)
      {
        return _turbosight.SendPmt(ListManagementType.Only, CommandIdType.Descrambling, context.PMT, context.PMTLength);
      }

    This means that strictly speaking the CAM will only decrypt one channel per tuner. Your CAM might not stop decrypting a channel until it runs out of capacity to decrypt a new channel, and that is why I say the behaviour you're seeing might be CAM dependent.

    Does this make sense? :)
     

    FreakyJ

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    Ahhhh yes this all makes sense :) thank you so much for your great explanation!
     

    johnzered

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    Just wanted to report back that I've had my new TBS 6618 card now for a few weeks and it's been working great. Tested with both MP1+patch and MP2. Thank you @FreakyJ and @mm1352000 for your help!
     

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