GTS Transceiver PHY User Guide: Agilex™ 3 FPGAs and SoCs

ID 848344
Date 8/04/2025
Public
Document Table of Contents

3.3.4. RX Datapath Options

Figure 33. RX Datapath Options in Parameter Editor
Table 24.  RX Datapath Options Parameters
Parameter Values Description
RX PMA Parameters
PRBS monitor mode

disable, PRBS7, PRBS9, PRBS10, PRBS13, PRBS15, PRBS23, PRBS31

Enables hard PRBS verifier with the PRBS polynomial selection. Default value is disable.

Enable rx_cdr_divclk

On/Off

Enables the port representing RX CDR clock output from RX PMA to the local reference clock pin (set as output) or the CDR clock output pin. Default value is Off.

RX CDR Settings
Output frequency Output Specifies the non editable RX CDR output frequency initial value derived from the IP configuration.
VCO frequency Output Specifies the non editable RX CDR VCO frequency initial value derived from the IP configuration.
RX CDR reference clock frequency 25 to 380 MHz Selects the reference clock frequency (MHz) for CDR. Default value is 156.25 MHz.
CDR lock mode auto

manual

When auto is selected, during user initiated reset or power-up, CDR first tries to lock to reference and then locks to data if present. By default, loss of lock to data re-triggers reset RX PMA reset. When manual is selected, you must drive i_rx_set_locktoref to control the CDR lock behavior. If i_rx_set_locktoref is low CDR operates in auto mode, and in lock to reference mode if it is high. When Enable rx_cdr_divclk is enabled, only auto mode is available. Default value is auto.
Enable rx_set_locktoref port On/Off This parameter is valid only when CDR lock mode is set to manual lock to reference. Asserting this signal keeps CDR in lock to reference mode. Deasserting this signal keeps CDR in auto mode. When switching modes, assert reset. Default value is Off
Enable rx_cdr_fast_freeze_sel port On/Off This port is used for GPON. When the PMA configuration rules parameter is set to GPON, you must enable and tie the i_rx_cdr_fast_freeze_sel signal to 1'b0. It ensures that the i_rx_cdr_freeze signal propagates correctly. Default value is Off.
Enable rx_cdr_freeze port On/Off This port is used for GPON. When the PMA configuration rules parameter is set to GPON, you must enable and drive the i_rx_cdr_freeze signal to freeze the CDR lock state during non-active time slots. Default value is Off