Ieee 1588v2 ingress receive signals, Ieee 1588v2 ingress receive signals -23 – Altera Low Latency Ethernet 10G MAC User Manual
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Signal
Direction
Width
Description
tx_etstamp_ins_ctrl_offset_
checksum_field[]
In
16
The location of the checksum field,
relative to the first byte of the packet.
Assert this signal in the same clock
cycle as the start of packet (avalon_
st_tx_startofpacket is asserted).
tx_etstamp_ins_ctrl_offset_
checksum_correction[]
In
16
The location of the checksum
correction field, relative to the first
byte of the packet. Assert this signal
in the same clock cycle as the start of
packet (avalon_st_tx_startofpacket is
asserted).
IEEE 1588v2 Ingress Receive Signals
The signals below are present when you select the Enable time stamping option.
Table 5-19: IEEE 1588v2 Ingress Receive Signals
Signal
Direction
Width
Description
rx_ingress_timestamp_96b_valid
Out
1
When asserted, this signal qualifies
the timestamp on
rx_ingress_
timestamp_96b_data[]
. The MAC
IP core asserts this signal in the same
clock cycle it asserts
avalon_st_rx_
startofpacket
.
rx_ingress_timestamp_96b_data[]
Out
96
Carries the 96-bit ingress timestamp
in the following format:
• Bits 48 to 95: 48-bit seconds field
• Bits 16 to 47: 32-bit nanoseconds
field
• Bits 0 to 15: 16-bit fractional
nanoseconds field
The 96-bit timestamp is usually for
noting the complete ToD and is
useful in ordinary clock and
boundary clock devices. The
transparent clock typically uses 64-bit
timestamp.
rx_ingress_timestamp_64b_valid
Out
1
When asserted, this signal qualifies
the timestamp on
rx_ingress_
timestamp_64b_data[]
. The MAC
IP core asserts this signal in the same
clock cycle it asserts
avalon_st_rx_
startofpacket
.
UG-01144
2014.12.15
IEEE 1588v2 Ingress Receive Signals
5-23
Interface Signals for LL Ethernet 10G MAC
Altera Corporation