7.
Configure Delay Asymmetry
Modify the 'PRIMARY ETH PORT DELAY ASYMMETRY' setting if the delay asymmetry in the network link is
known, otherwise it is recommended that the setting is left as its default value of '0'.
PTP automatically calculates the propagation delay between a server and client, but this calculation assumes
the delay in each direction of transmission is the same. PTP cannot measure and compensate for delay
asymmetry, which means that the presence of delay asymmetry reduces PTP time accuracy.
Delay asymmetry is calculated from the server to client path delay minus the client to server path delay. A
client uses the delay asymmetry value to compensate for the delay asymmetry error caused in the PTP delay
calculation mechanism.
If the delay asymmetry is known, entering it manually will allow it to be compensated for, and improve time
accuracy. The input range is 3.2768e+14 ns×2
^16
to −3.2768e+14 ns×2
^16
(-5 to 5 seconds).
8.
Configure Announce Interval
The 'ANNOUNCE INTERVAL' specifies the time interval between successive Announce messages being sent
to other PTP devices on the network.
By default, this is set to 1 in 2
^n
seconds, or 2 seconds. The supported range is 0-4 in 2
^n
seconds, or 1-16
seconds
9.
Announce Receipt Timeout
By default the 'ANNOUNCE RECEIPT TIMEOUT' is set to 3. This means that after 3 announce intervals, if
the device has not recieved an announce message it will trigger an announce receipt timeout event, which will
move the port into a listening state.
10.
BMCA
By default, the 'BMCA' operations will be set to 'BASIC' and will operate as defined in IEEE 1588v2-2008
11.
Clock Class Rules
By default, the 'CLOCK CLASS RULES' operations will be set to 'BASIC' and will operate as defined in IEEE
1588v2-2008
12.
TLV Settings > Alternate Time Offset in Outgoing
By default the 'ALTERNATE TIME OFFSET IN OUTGOING' is set to false, preventing the ATOI TLV from
being sent on outgoing packets.
13.
TLV Settings > ATOI and C37.238 Require on Incoming
By default, the 'ATOI AND C37.238 REQUIRE ON INCOMING' setting is set to false.
14.
TLV Settings > C37.238 TLV Outgoing
By default, the 'C37.238 TLV OUTGOING' is set to false, preventing the C37.238 TLV from being sent on
outgoing packets.
15.
Save Settings
Provisioning
©
2022 Microchip Technology Inc.
and its subsidiaries
Manual
DS00004572A-page 112
