Siemens RUGGEDCOM RX1100, Installation Manual

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RUGGEDCOM RX1100
Installation Guide
Chapter 3
Communication Ports
Precision Time Protocol (PTP) Ports 23
1 8
Figure 26: Serial RJ45 Port Pin Configuration
Pin RS232 Mode RS485 Mode RS422 Mode
1
a
DSR/RI RX-
2
a
DCD
3 DTR
4 Common (Isolated) Ground
5 RX RX+
6 TX TX/RX+ TX+
7 CTS
ab
8 RTS
b
TX/RX- TX-
Shield Chassis Ground
a
Connected internally.
b
In RS232 mode, this pin enters a high impedance state. A DTE that asserts RTS will see CTS asserted, although the device will not perform hardware flow
control.
Section 3.8
Precision Time Protocol (PTP) Ports
The optional Precision Time Protocol (PTP) card for the RX1100 provides accurate time synchronization across
local and wide area networks. The PTP card is capable of using a variety of time synchronization methods
including Network Time Protocol (NTP), IRIG-B, and IEEE 1588, making it a flexible product for new and existing
installations.
1 2 3 4 5
Figure 27: PTP Card
1. IEEE 1588 Ethernet Interface 2. GPS Antenna Input 3. IRIG-B AM Output 4. IRIG-B PWM (TTL) or PPS Output 1 5. IRIG-B PWM
(TTL) or PPS Output 2
NTP is the standard for synchronizing the clocks of computer systems throughout the Internet and is suitable for
systems that require accuracies in the order of 1 ms. IRIG-B time synchronization relies on the Global Positioning
System (GPS) as the source of accurate time and requires an external GPS antenna input to provide accurate
time signals on the order of 100 µs. IEEE 1588 is designed to fill a niche not well served by either of the two
dominant protocols, NTP and IRIG-B. IEEE 1588 is designed for local systems requiring accuracies on the order
of 100 nanoseconds. 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 PTP card is an ideal product for use in existing installations already well served by NTP and/or GPS. It also
provides a migration path for the use of the new IEEE 1588 standard. As more end devices enter the market with
IEEE 1588 compatibility, this card provides an easy transition to this new time synchronization standard.