Intel E810 VDA4T Series User Manual

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Intel
®
Ethernet Network Adapter E810-XXVDA4T
User Guide
4.12 1PPS Signals from E810 Device to DPLL
The E810-XXVDA4T implements two 1PPS signals coming out of the MAC (E810 device) to the DPLL.
They serve as the phase reference (CVL-SDP20) and as both phase and frequency reference (CVL-
SDP22) signals.
To enable a periodic output, write five integers into the file: channel index, start time seconds, start
time nanoseconds, period seconds, and period nanoseconds. To disable a periodic output, set all the
seconds and nanoseconds values to zero.
1. To enable the phase reference pin (CVL-SDP20):
# echo 1 0 0 1 0 > /sys/class/net/$ETH/device/ptp/ptp*/period
2. To enable the phase and frequency reference pin (CVL-SDP22):
# echo 2 0 0 1 0 > /sys/class/net/$ETH/device/ptp/ptp*/period
3. To disable the phase reference pin (CVL-SDP20):
# echo 1 0 0 0 0 > /sys/class/net/$ETH/device/ptp/ptp*/period
4. To disable the phase and frequency reference pin (CVL-SDP22):
# echo 2 0 0 0 0 > /sys/class/net/$ETH/device/ptp/ptp*/period
Note: Enabling the phase and frequency reference signal (CVL-SDP22) on the adapter without
external reference (ptp4l) is not recommended and might cause a frequency drift.
4.13 1PPS Signals from the DPLL to E810 Device
The DPLL automatically delivers two 1PPS signals to the E810 device on pin 21 and 23. These signals
can be used to synchronize the E810 to the DPLL phase with the ts2phc program. The E810 will capture
the timestamp when the 1PPS signal arrives.
To ensure that the timestamps from the 1PPS signals are only used when the DPLL is locked to a signal,
you can enable the 1PPS filtering option. By default, filtering is disabled, and all the timestamps are
passed along by the E810 ice driver.
The DPLL 1PPS filtering can be enabled (on) or disabled (off) by using the ethtool command in the Linux
kernel.
# export ETH=ens801f0
#ethtool --show-priv-flags $ETH
Private flags for ens801f0:
link-down-on-close : off
fw-lldp-agent : off
channel-inline-flow-director : off
channel-inline-fd-mark : off
channel-pkt-inspect-optimize : on
channel-pkt-clean-bp-stop : off
channel-pkt-clean-bp-stop-cfg: off
vf-true-promisc-support : off
mdd-auto-reset-vf : off
vf-vlan-pruning : off
legacy-rx : off
dpll_monitor : on
extts_filter : off
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Intel E810 VDA4T Series Specifications

General

Brand	Intel
Model	E810 VDA4T Series
Category	Adapter
Language	English