S7-1500 and Sinamics drive: how to read telegrams in PLC program?

Hi Experts,
I'm new to Siemens world. At the present time I'm programming a drive in TIA Portal.
My setup is: Inverter G120 + CU 250S-2 + S7-1500.

I'm at 90% of the job but I still need to improve some things. For that I need to read some bits of of the telegram that is sent from/to the CU.

I programmed the system with Telegram 111 (now switched to free telegram to have more control on the drive but the basic mapping is the same), so the structure is this:


The CU communicates to the PLC through:


I tried to read the bits from I6.0 to I7.7 to see the third word but the result doesn't match with the word that I can read from the startdrive (It should be the same, shouldn't it?):



So I am doing something wrong.
What sould I do to read the bits in the last picture?
Thanks

Can you show how you are mapping POS_STW2 into the 3rd word of the telegram?

The words should be set by telegram 111 (picture above). I didn't map any word. I am just following the manual (first picture) but I don't understand these discrepancies reported in the first post.
By the way, my drive is fully working and the position function is OK.
Thanks