SIIG RS-422 User manual

1
USB to RS-422/485
Serial Adapter
Quick Installation Guide
04-0862A
Introduction
The USB to RS-422/485 Serial Adapter provides
additional RS-422/485 serial port(s) to your
systems.
Key Features and Benefits
• Compliant with Universal Serial Bus 2.0
Specification
• Supports serial port data transfer rates up
to 1 Mb/s
• Built in 15KVDC ESD serial interface
protection
• LED indicators for TxD/RxD activities
• Metal housing with wall mount ready
System Requirements
• Desktop or notebook computer with an
available USB port

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• Windows® 8 (32-/64-bit) / Windows 7 (32-
/64-bit) / Vista (32-/64-bit) / XP (32-/64-
bit) / Server 2003 & 2008 (32-/64-bit) /
Server 2008 R2
Package Contents
•USB to RS-422/485 Serial Adapter
• USB cable (Type A/B)
• Termination resistor jumpers (2 for ID-
SC0P11-S1, 4 for ID-SC0Q11-S1, 8 for ID-
SC0R11-S1)
• Software CD & quick installation guide
Layout
1-Port USB to RS-422/485 Serial Adapter
Figure 1: ID-SC0P11-S1 Layout
Status LED
Serial output DIP switch
USB Type B

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Figure 2: ID-SC0Q11-S1 Layout
2-Port USB to RS-422/485 Serial Adapter
4-Port USB to RS-422/485 Serial Adapter
Figure 3: ID-SC0R11-S1 Layout
DIP switch (P2)
DIP switch
(P1)
USB Type B
Serial output
Status LED
• Tx: Flashing green when sending data
• Rx: Flashing yellow when receiving data
Serial output
DIP switch (P1-P4)
Status LED
Status LED
USB Type B
5V power jack
(optional)

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• 5V power jack (optional): Connect your
power adapter here (not included).
Note: Most serial devices do not require
additional power through the serial port.
Refer to your serial device's manual for
more information.
DIP Switch
Auto RS-422/485 (1-ON, 2-OFF)
This is default setting. The COM port will
automatically detect device status and control
the data transmitting or receiving. See Figure 4a.
RS-422 or 4-Wire RS-485 (1-OFF, 2-ON)
Full duplex mode. See Figure 4b.
Auto RS-422/485 RS-422 or 4-Wire RS-485
Figure 4a Figure 4b

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Termination Resistor
Open the cover of the USB to RS-422/485 Serial
Adapter to configure the jumper settings.
1. Unscrew the screw(s) at the bottom of the
Adapter.
2. Slide the bottom cover in the direction of the
serial output to open.
Serial output
Figure 5
Figure 6
Bottom screw
3. Follow the instructions on page 6 to
configure the jumper settings.

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Jumper Settings
RS-422 or 4-wire RS-485 working model with
termination resistor.
2-wire RS-485 working model with termination
resistor.
The adapter comes with Tx and Rx termination
resistors for each serial port. You can configure
the jumper settings to avoid impedance
mismatched problems.
Device
Device
USBtoRS-422/485
Serial Adapter
USBtoRS-422/485
Serial Adapter
Default jumper setting is Open (disconnect 120
ohms termination resistor across the two wires).

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Figure 7: Tx and Rx jumper for each port
Pin Assignment
P1- Rx P1- Tx
15
69
Note:Pins 6 to 9 have no function.
Figure 8: Pin assignment

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RS-422 Wire Diagram
USBtoRS-422 RS-422 device
Pin 1: TxD-
TxD-
Pin 2: TxD+
TxD+
RxD+
Pin 4: RxD+
RxD-
Pin 3: RxD-
Figure 9: point-to-point / 4-wire full-duplex communication
USBtoRS-422 RS-422 device
RS-422 device
RS-422 device
Figure 10: point-to-multi point / 4-wire full-duplex
communication

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RS-485 Wire Diagram
Pin 1: TxD-
Pin 2: TxD+
Pin 4: RxD+
Pin 3: RxD-
Figure 11: Point-to-point / 2-wire half-duplex
communication
USBtoRS-485 RS-485 device
D+
D-
Figure 12: Point-to-multi point / 2-wire half-duplex
communication
USBtoRS-485 RS-485 device
RS-485 device
RS-485 device

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Windows Installation
Follow the instructions below to install the USB to
RS-422/485 Serial Adapter drivers.
Note: Do not plug the Adapter to your
computer until instructed to do so.
Windows 8 (32-/64-bit) / Windows 7 (32-/
64-bit) / Server 2008 R2
1. Insert the driver CD. Close the CD autoplay
box if prompted.
2. Press Windows key and R, type
D:\setup.exe, and click OK.(Change D: to
match your CD/DVD-ROM drive letter)
3. At the User Account Control, click Yes.
For 2008 R2, skip this step.
4. At the Program Compatibility Assistant,
click close. Skip this step if not prompted.
5. Repeat step 2 & 3.
6. Plug the adapter into the computer, click
Cancel at the Found New Hardware (if
prompted). The driver will install
automatically.