Introduction
1.7.2 TTL Outputs
IRIG-B PWM
IRIG-B time synchronization is an even older, established, inter-device time
synchronization mechanism providing accuracy in sub-milliseconds.
IEEE 1588
IEEE 1588 is designed to provide networked, packet-based time synchronization
between different networking nodes (PTP devices). The RUGGEDCOM RS416F
supports PTP v2, which is defined in the IEEE 1588-2008 standard. IEEE 1588
is designed to fill a niche not well served by either of the two older, dominant
protocols, NTP and IRIG-B. IEEE 1588 is also designed for applications that cannot
bear the cost of a GPS receiver at each node or for which GPS signals are inaccessible.
The RUGGEDCOM RS416F only supports ordinary clock mode. An ordinary clock can
be configured as either a Grandmaster Clock (GM) or a Slave Clock (SC) within the
master-slave hierarchy.
Every Ethernet port on the RUGGEDCOM RS416F supports IEEE 1588. For more
information, refer to
1.7.2
TTL Outputs
The PTP card provides a TTL (Transistor-Transistor Logic) output.
The TTL OUT port supports the IRIG-B PWM and PPS signal formats. Enabling/
disabling the output port and selecting the signal format is controlled through the
RUGGEDCOM RS416F operating system.
The number of devices that can be connected to the TTL Out port is dependent on
the cabling type and length, as well as the input impedances of the devices. The
following simplified circuit schematic shows the interface between an IRIG-B source
and connected devices.
V
S
R
S
R
C
R
L
/N
3
2
1
1
Source
2
Cabling
RUGGEDCOM RS416F
Installation Manual, 04/2021, C79000-G8976-1354-04
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