Introduction, Supported serial protocols, Rs-232 – Lantronix ETS16PR User Manual
Page 7: Rs-423
ETS Installation Guide
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The Lantronix ETS (ETS8PS, ETS16PS, ETS16PR, and ETS32PR) is a multi-port
device server providing shared network access to terminals, devices, console ports,
and printers for a variety of network protocols and operating systems. The ETS
supports the TCP/IP, IPX (NetWare), Local Area Transport (LAT), AppleTalk
(EtherTalk), and Microsoft LAN Manager protocols.
Note:
In this manual, all ETS servers will be referred to as “the ETS” unless
a distinction needs to be made between models.
The ETS stores its executable software in Flash (rewritable) ROM, meaning that it
does not have to download software from a host each time it boots. Software must
only be downloaded when a new software version becomes available. See
Supported Serial Protocols
All ETS models support the RS-232/423 serial protocol.
RS-232
The RS-232 line interface standard is a single-ended peer-to-peer interface. Today's
personal computers typically have at least one RS-232 serial port. It is the most
common serial protocol used today.
RS-232 is used for connecting devices across short distances at speeds up to 230.4
kb/s. Faster speeds require shorter cabling to ensure error-free communication. The
maximum cable length at a given speed is determined by many factors, including the
immediate electrical environment and the quality of cable used, but is usually less
than 15 meters at high speeds.
RS-423
All of the ETS models support the RS-423 line interface standard. RS-423 devices
are interoperable with RS-232 devices. That is, RS-232 ports can receive data
reliably from RS-423 ports and vice-versa.
The main difference between RS-423 and RS-232 is that RS-423 employs lower
voltage signaling and differential receivers. RS-423 still uses single-ended
transmitters for compatibility with RS-232 receivers.
RS-423 is generally rated at higher speeds over longer cabling runs than RS-232.
Maximum data rates of 230.4 kb/s are possible on ETS-PR models, and 115.2 kb/s is
the maximum on ETS-P models.