Global Time PTPv2
FMADIO capture systems support PTPv2 using the linux PTP open source project. ( http://linuxptp.sourceforge.net/ ) running only on the 10G management interface. 1G links are supported using 1G RJ45 SFP transceiver.
Enabling PTPv2 via GUI is as follows
In addition the 10G Bridged networking config must be disabled. As LinuxPTP must run directly on the bare metal NIC. Please edit the file
Change the "phy10" values as shown below to "man10"
Changed to "man10" as follows
System must be rebooted for the above to take effect.
PTPv2 VLAN Interface
In some environments PTPv2 is run on its own dedicated VLAN interface. To enable this update the configuration file
Specifically setting the VLANID as follows, in the below example its set to VLANID "123"
After editing save and confirm the file syntax is correct, ensure there are no syntax or parse errors. The correct output is shown below.
Either reboot the system, or kill all ptp processes (e.g. sudo killall ptp4l; sudo killall phc2sys)
On reboot a man10.123 VLAN interface that matches the set VLANID should be populated as follows
And the linux ptp daemo should have binded to the newly created instance as follows
And the PHC interface also
PTPv2 on Second 10G Port
The above config assumes PTPv2 is running on the primary 10G management port. There is not requirement for using the primary port, instead the 2nd 10G management port can also be used. Below are the differences required
1) in the udev rules phy10 -> phy11 -> man11
Use phy11 interface
Rename to man11
2) Set the IP address of man11
man11 needs to be configured with an IP address, either editing network config file directly
or using the fmadiocli command line utility
3) Specify man11 in the ptp config per below
PTP on the Second 1G RJ45 Port
PTPv2 can be run on the 2nd 1G management interface, as it supports both a PHC clock and IEE1588 hardware timestamping.
NOTE: PTPv2 can not be run on the primary/first 1G interface as this is a software bridged interface and does not support hardware timestamping.
1) Configure the udev rules as follows
Set the phy1 interface renamed to man1 as shown below
2) Set the IP address of man1
man1 needs to be configured with an IP address that the PTP master can reach. Set the network information either editing network config file directly
or using the fmadiocli command line utility
3) Specify man1 in the ptp config per below
Custom LinuxPTP Config
FMADIO system use the standard LinuxPTP project for time synchronization
As such the PTP configuration is highly customizable. For example Broadcast environments use a non standard domain and update rate. FMADIO support this by using a custom LinuxPTP configuration file.
Custom config file can be located below
If this file is present the system will use it when starting the application ptp4l.
After creating or editing the file, need to stop ptp4l as follows
The system will then automatically start it on a 60sec timer.
Logfiles for debugging can be found in
PPS Time Synchronization
FMADIO Devices have a PPS input connect that expect 1 1PPS 50ohm 5V signal. The start of second boundary occurs on the rising edge of the PPS clock. Required hold time is 100usec or more.
Enabling of PPS is automatic, when the system detects PPS input, it automatically selects PPS to discipline the timestamp clock.
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