- If the module includes flow control but is not being
used, make sure the request signals are not currently driven Low.
s_axi_nfc_tx_tvalid and s_axi_ufc_tx_tvalid
are active-High. If they are High, s_axi_tx_tvalid stays Low
because the channel is being allocated for flow control.
- If NFC is enabled, make sure the channel partner
did not send an NFC XOFF message. This cuts off the channel for normal data until
the other side sends an NFC XON message to turn the flow on again. See Native Flow Control Interface
for
more details.