ATEN Interface Converter IC-485S User manual

User Manual
IC-485S /IC-485SI
Read this guide thoroughly and follow the installation and operation
procedures carefully in order to prevent any damage to the units and/or
any devices that connect to them.
This package contains:
M1 IC-485S or IC-485SI Interface Converter
M1 Power Adapter (DC 9V; 300mA)
M1 User Manual
If anything is damaged or missing, contact your dealer.
©Copyright 2005 ATEN®International Co., Ltd.
Manual Part No. PAPE-0075-201
Printed in China 01/2005
All brand names and trademarks are the registered property of their respective owners.
2005-01-04

Warning! This equipment has been tested and found to comply
with the limits for a Class A digital device, pursuant to Subpart J
of Part 15 of the FCC Rules. These limits are designed to provide
reasonable protection against harmful interference when the
equipment is operated in a commercial environment. This
equipment generates, uses and can radiate radio frequency
energy and, if not installed and used in accordance with the
instruction manual, may cause interference to radio
communications.Operationof thisequipmentin aresidentialarea
is likely to cause harmful interference, in which case the user will
be required to correct the interference at his own expense.
2005-01-04

Overview
Although RS-232 serial ports are found on almost every computer,
because of their slow transmission speeds, limited range, and limited
networking capabilities, they are not an effective solution for industrial
strength long distance communications systems.
Systems based on the RS-485 standard, however, utilize different
voltage lines for the data and control signals, so they are not subject to
the RS-232 limitations.
The IC-485S / IC-485SI is a bidirectional converter that transparently
converts RS-232 signals to RS-485 signals (and vice versa). The
IC-485S / IC-485SI provides Point-to-Point; Multidrop; and Simplex
operations over distances of up to 1200 m (4000 ft.), thus permitting the
creation of reliable long distance data communications systems using
standard computer hardware.
- 1 -
2005-01-04

Switch Configuration
The IC-485S / IC-485SI’s operating mode parameters are set with two
slide switches:
MSW1 sets the Device Mode
MSW2 sets the Transmitting and Receiving Mode
IC-485S Switch Settings
Position Setting
SW1 SW2
1 DCE TxO, RxON
2 DTE TxRTS, RxRTS
3Monitor
TxRTS, RxON
- 2 -
Spare
Power Jack
RJ-11
Terminal Block
SW 1
SW 2 RS-232 DB-25 Female Connecter
2005-01-04

IC-485SI Switch Settings
Position Setting
SW1 SW2
1 DTE TxO, RxON
2 DCE TxRTS, RxRTS
3X
TxRTS, RxON
- 3 -
Power Jack
Grnd.Tab
T
erminal Block
SW 1
SW 2 RS-232 DB-25 Female Connect
er
2005-01-04

Terminology
Explanations of the SW1 and SW2 terms are given in the table below:
Term Explanation
DCE Data Communications Equipment; if the IC-485S /
IC-485SI is going to be plugged into a DTE device,
the IC-485S / IC-485SI must be set to DCE.
DTE Data Terminating Equipment; if the IC-485S /
IC-485SI is going to be plugged into a DCE device,
the IC-485S / IC-485SI must be set to DTE.
TxON, RxON This setting is used in Point-to-Point operations, in
which the unit is always in Transmitting and
Receiving Mode.
TxRTS, RxRTS This setting is used in Multidrop operations, in
which the unit is in Transmitting Mode when the
RTS signal is high, and is in Receiving Mode when
the RTS signal is low.
TxRTS, RxON This setting is used in Multidrop Full Duplex
operations to monitor the RS-485 line signals.
Receiving Mode is always ON. Transmitting mode
only occurs when the RTS signal is high.
- 4 -
2005-01-04

Operating Modes
The IC-485S / IC-485SI supports four operating modes: Point-to-Point;
Multidrop; Simplex; and Monitor (IC-485S only). Point-to-Point and
Multidrop can be configured for Full or Half Duplex. Each of the
operating modes is explained in the sections that follow.
Point-to-Point
A Point-to-Point configuration is one in which two devices, located at
two different places are linked for communication by a pair of IC-485S
or IC-485SI units. There are two configurations: Point-to-Point Full
Duplex, and Point-to-Point Half Duplex.
1. Point-to-Point Full Duplex
MPoint-to-Point Full Duplex uses reverse four wire cabling, as
shown in the diagram below:
MFor both IC-485S / IC-485SI units, set SW1 to DCE or DTE de-
pending on what type of device the IC-485S / IC-485SI will plug
into (if it will plug into a DCE device, configure it for DTE, and
vice versa).
MFor both IC-485S / IC-485SI units, set SW2 to TxON, RxON.
- 5 -
T+
T-
R-
R+
R+
R-
T-
T+
C
onnect
t
o PC#1's
C
OM port
Connec
t
to PC#2
's
COM po
rt
DB-25 DB-25
2005-01-04

2. Point-to-Point 2 Wire Half Duplex
MPoint-to-Point Half Duplex uses straight through four wire ca-
bling, as shown in the diagram below:
MFor both IC-485S / IC-485SI units, set SW1 to DCE or DTE de-
pending on what type of device the IC-485S / IC-485SI will plug
into (if it will plug into a DCE device, configure it for DTE, and
vice versa).
MFor both IC-485S / IC-485SI units, set SW2 to TxRTS, RxRTS.
Note: The RTS signal is controlled by an external software
command. The IC-485S / IC-485SI has no capability to
control this signal by itself.
- 6 -
T+
T-
R-
R+
R+
R-
T-
T+
C
onnect
t
o PC#1's
C
OM port
Connec
t
to PC#2
's
COM po
rt
DB-25 DB-25
2005-01-04

Multidrop
A Multidrop configuration is one in which more than two devices are
linked for communication using several IC-485S / IC-485SI units.
One of the devices that one of the IC-485S / IC-485SIs connects to is
designated as the Master device. All the remaining devices that the rest
of the IC-485S / IC-485SIs connect to are designated as Slave devices.
There are two configurations: Multidrop Full Duplex, and Multidrop Half
Duplex.
1. Multidrop 4 Wire Full Duplex
MMultidrop Full Duplex uses reverse four wire cabling to link all the
connected IC-485S / IC-485SI units:
MFor all IC-485S / IC-485SI units, set SW1 to DCE or DTE depend-
ing on what type of device the IC-485S / IC-485SI will plug into (if
it will plug into a DCE device, configure it for DTE, and vice
versa).
MFor the Master unit, set SW2 to TxON, RxON.
MFor all Slave units, set SW2 to TxRTS, RxON.
- 7 -
Master
T+
T
-
R
-
R+
Slave 1
R+
R -
T -
T+
Slave 2
R+
R -
T -
T+ .
.
.
Slave 31
P
C1
C
OM1/
C
OM2
PC2
COM
1/
COM
2
PC3
COM
1/
COM
2
2005-01-04

2. Multidrop Half Duplex
MMultidrop Half Duplex uses straight-through four wire cabling, to
link all the connected IC-485S / IC-485SI units:
MFor all IC-485S / IC-485SI units, set SW1 to DCE or DTE depend-
ing on what type of device the IC-485S / IC-485SI will plug into (if
it will plug into a DCE device, configure it for DTE, and vice
versa).
MFor all IC-485S / IC-485SI units set SW2 to TxRTS, RxRTS.
Note: The RTS signal is controlled by an external software
command. The IC-485S / IC-485SI has no capability to
control this signal by itself.
- 8 -
Master
T+
T
-
R
-
R+
Slave 1
R+
R -
T -
T+
Slave 2
R+
R -
T -
T+
P
C1
C
OM1/
C
OM2
PC2
COM
1/
COM
2
PC3
COM
1/
COM
2
Slave 3
R+
R -
T -
T+ .
.
Slave 31
PC4
COM
1/
COM
2
2005-01-04