What is the purpose of the 5v only common interface port on Samsung?

Hello,
You gave an answer regarding the CI reader that equips a television. Perhaps you can enlighten me.

I just acquired a SAMSUNG PS50C6970 plasma. It is a high-end model that includes full HD, 3D function, recording function to external HDD, terrestrial TNT tuner, and Satellite tuner (decoder). There is a free connection at the back of the set that allows you to connect a CI module, also called CI CARD PCMCIA VIACCESS 3.0 or CAM CI card module. This module can accommodate a card in the format of Canal+ or VIACCESS TNTSAT.
I live in a place where the terrestrial waves do not reach. I was therefore forced to invest 220 euros in a decoder with its viaccess card to be able to benefit from French television (including TNT via satellite network). TNT is thus only free for city dwellers!
Today, I would like to free the unnecessary bulk of my 220 euro decoder by using the one integrated into my beautiful television by inserting my viaccess card into the PCMCIA VIACCESS module, but a seller of this famous module told me that it would not work! According to him, you need to use a specific decoder because there is special encoding. Therefore, you cannot use the "free" decoder installed in televisions!!
I find this absurd because, in addition to being paid, TNT is also restrictive in this case.
Can you confirm whether what the seller told me is accurate?

The TNT Sat card only works with TNT Sat; it has a slot on your TV that receives a PCMCIA card reader, into which you can insert a prepaid Viaccess card or one provided by an access provider like CanalSat, or others...
Today, the Fransat or TNT Sat decoders that allow access to TNT via satellite are practically reimbursed by the state for people living in areas where TNT cannot be received except via satellite.

"he has a slot on your TV that receives a pcmcia card reader, in which you can insert a prepaid viaccess card or one provided by an access supplier like canalsat" ... do you simply need to pay for the viaccess card and that’s it? no need to connect the antenna or have a receiver (the decoder for TNT Canal, etc.)????? thank you in advance, gentlemen! :)"

We bought a Samsung TV with a CI+ card slot and built-in satellite reception. We set everything up, returned the Canal+ decoder, and bought a Samsung Blu-ray satellite recorder in Germany. Everything is perfect, except that we no longer have HD on the decoded channels (it seems that Canal+ has changed its HD encoding). Does anyone know if a new CI+ satellite module decodes HD?

Hello Sylvianne, I also have a Samsung LCD TV with a satellite decoder (DVB-S) that I bought in Germany two years ago because it was impossible to find one in France, except for high-end models, as I wanted to get rid of the C+ decoder (€8/month). What you need to know is that first of all, you must have the HD option with C+ (they're thieves, we know that) and secondly, the CI adapter (which is where the C+ card goes) must support HD.
Best regards