Altera 10-Gbps Ethernet MAC MegaCore Function - Manual (Page 165)

C–4 Appendix C: Packet Classifier
10-Gbps Ethernet MAC MegaCore Function User Guide February 2014 Altera Corporation
C.2.4. Control Insert Signals
Table C–5 describes the control insert signals for the Packet Classifier. These signals
must be aligned to the start of a packet .
C.2.5. Timestamp Field Location Signals
Table C–6 describes the timestamp field location signals for the Packet Classifier.
These signals must be aligned to the start of a packet .
tx_etstamp_ins_ctrl_in_residence_time
_calc_format
Input 1
Format of the timestamp to be used for
calculating residence time. This signal must be
aligned to the start of an incoming packet.
A value of 0 indicates 96 bit timestamp format
while 1 indicates 64 bit timestamp format.
tx_etstamp_ins_ctrl_out_residence_tim
e_calc_format
Output 1
Format of the timestamp to be used for
calculating residence time. This signal must be
aligned to the start of an outgoing packet.
A value of 0 indicates 96 bit timestamp format
while 1 indicates 64 bit timestamp format.
Table C–4. Ingress Control Signals for the Packet Classifier (Part 2 of 2)
Signal Direction Width Description
Table C–5. Control Insert Signals for the Packet Classifier
Signal Direction Width Description
tx_etstamp_ins_ctrl_out_checksum_zero Output 1 Assert this signal to set the checksum field.
tx_etstamp_ins_ctrl_out_checksum_corr
ect
Output 1
Assert this signal to correct the packet
checksum by updating the checksum correction
specified by
tx_etstamp_ins_ctrl_out_offset_check
sum_correction .
tx_etstamp_ins_ctrl_out_timestamp_for
mat
Output 1
The timestamp format of the frame where the
timestamp is inserted.
tx_etstamp_ins_ctrl_out_timestamp_ins
ert
Output 1
Assert this signal to insert timestamp into the
associated frame.
tx_etstamp_ins_ctrl_out_residence_tim
e_update
Output 1
Assert this signal to add the residence time into
the correction field of the PTP frame.
Table C–6. Timestamp Field Location Signals for the Packet Classifier
Signal Direction Width Description
tx_etstamp_ins_ctrl_out_offset_timest
amp
Output 16 Indicates the location of the timestamp field.
tx_etstamp_ins_ctrl_out_offset_correc
tion_field
Output 16 Indicates the location of the correction field.
tx_etstamp_ins_ctrl_out_offset_checks
um_field
Output 16 Indicates the location of the checksum field.
tx_etstamp_ins_ctrl_out_offset_checks
um_correction
Output 16
Indicates the location of the checksum
corrector field.