TRansceiver CDR Cy IV

Hello:

The CDR has two modes of operation LTR (lock to reference) or LTD (lock to data). The signal

rx_freqlocked Receiver CDR lock state indicator

■ A high level indicates the CDR is in LTD state.

■ A low level indicates the CDR is in LTR state.

The receiver is fully functional until 2.0GB receiving the correct data, however I noticed that the signal rx_freqlocked in signal Tap is never high (in theory the CDR is still in LTR mode).

My question is , is it possible for the receiver to be functional if the CDR is still in LTR and I am just getting lucky or I have something wrong with the probing of rx_freqlocked ? I am sampling the signal directly from the GBX block without any logic in between. The TXCVR spec. says that the CDR ignores incoming data but I am not sure what it means to the receiver output since I am getting the correct data.

thank you

Ref: Cy IV TXCVR spec Figure 1-15