GTS Transceiver PHY User Guide: Agilex™ 5 FPGAs and SoCs

ID 817660
Date 10/17/2025
Public
Document Table of Contents

3.5.7. RX PMA Status Signals

Table 50.  RX PMA Status Signals
Signal Name Clocks Domain/Resets Direction Description
o_rx_is_lockedtoref[N-1:0] asynchronous output CDR lock status signal.
  • 1’b1 – CDR is frequency locked to reference clock within the PPM threshold.
  • 1’b0 – CDR is not frequency locked to reference clock within the PPM threshold. Applicable to PMA block only

When lockedtodata stays high, the lockedtoref signal status is a don't care.

o_rx_is_lockedtodata[N-1:0] asynchronous output RX CDR data lock status signal.
  • 1’b0: CDR is not in locked-to-data mode.
  • 1’b1: CDR is in locked-to-data mode. Applicable to PMA block.

When asserted, indicates that the CDR is in locked-to-data mode. When continuously asserted and does not switch between asserted and deasserted, you can confirm that the CDR is actually locked to data. When toggling regularly, this signal indicates that the CDR is unlocked.

i_rx_set_locktoref[N-1:0] asynchronous input

1'b1: keep CDR in lock to reference mode.

1'b0: keep CDR in auto mode.

i_rx_cdr_freeze[N-1:0] asynchronous input This port is used in GPON to freeze the CDR lock state during inactive time-slots.
  • 1'b1: Freeze the CDR
  • 1'b0: Unfreeze the CDR
i_rx_cdr_fast_freeze_sel[N-1:0] asynchronous input This port is used in GPON for CDR freeze signal select. You must tie this signal to 1'b0 to ensure i_rx_cdr_freeze signal propagates correctly.