I’m a new user on this forum. I’ll explain you my problem.
I send a blink to the anchor and the anchor replies with ranging init but I have a problem.
After sending the blink, I want to display the data length and the fctrl  of the receive frame from anchor (the ranging init message)
But I receive a frame of 127 bytes and fctrl = 0x7f and not the 30 bytes from ranging init msg with a fctrl = 0x41.
When I use the tag with the anchor disconnected, the tag send a blink and indicates me that he receive a frame with fctrl = ed and data length = 0…
That produces an overrun interrupt when the anchor answer…
I don’t understand why. I receive the good frame only sometime but very poor.
Have you got this problem also ?