Does someone want help me understand how the Hytera DMR work?

[Lord of nothing]

In the CPS I can set for example:

Slot Operation
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Option Description
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...
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Pseudo Trunk: Both slots can be used simultaneously for communication or data transfer in Direct and Repeater modes. And in Repeater mode, the slot is alternative [portable and mobile radios only] .

And:

TDMA Direct Mode
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This option decides whether to enable the TDMA Direct Mode feature for the radio.

TDMA direct mode is applied to DMR digital radios. In this mode, one frequency supports calls in two slots synchronously. As for group calls in this mode, the members in the same group call must use the same slot, in order to avoid interfering communications in the other slot.

Option Description

Checked: To enable the TDMA Direct Mode feature of the radio.
Unchecked: To disable the TDMA Direct Mode feature of the radio.

Well why choose one of that option?  Its a legal PMR446 Radio and I try to understand all option. Well I know 80% of that and now I got it work after I got them used. In my case the work fine but I wish I would know everything.