2.0 GENERAL INFORMATION
Thank you for your purchase of this Patton Electronics product.
This product has been thoroughly inspected and tested and is
warranted for One Year parts and labor. If any questions or problems
arise during installation or use of this product, please do not hesitate to
contact Patton Electronics Technical Support at (301) 975-1007.
2.1 FEATURES
• Bi-directionally converts RS-232 signals to balanced RS-422
• DCE/DTE switch selectable on RS-232 interface
• Supports transmit and receive data (X-ON/X-OFF flow control)
• Loops back all handshaking signals on the RS-232 interface
• Very thin case (.75") for closely spaced computer ports
• No AC power or batteries required—draws all necessary operating
power from RS-232 interface
• Supports data rates to 19,200 bps
2.2 DESCRIPTION
The Patton Model 222N interface converter allows computers,
terminals and modems employing the RS-232E interface to
communicate with devices using RS-422 balanced electrical signals.
This unit derives the necessary power for operation from the data and
control voltages on the RS-232 interface. The 222N features
bi-directional data conversion at full or half duplex at distances up to 3.5
miles.
An external DCE/DTE switch lets you connect to the serial port of
either a computer/terminal (DTE) or a modem (DCE) without using a
crossover cable. The Model 222N is available with several RS-422
interface options: DB-25 male or female (following the RS-530
standard), RJ-11, RJ-45, or terminal blocks with strain relief.
The surge protected Model 222NS uses high speed avalanche
diodes to intercept data line transient surges and shunt them safely to
chassis ground. Compliant with IEC 801.5 level 2, 1kV, the 222NS can
protect itself and connected equipment from nearby lightning strikes,
and other surges of electromagnetic radiation.
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3.0 CONFIGURATION
The Model 222N is designed to be easy to use. There are no
internal jumpers or DIP switches to set, so there is no need to open the
case to configure the unit (you may need to open the case for wire
connection—refer to section 4.0). The only configuration necessary for
operation is proper setting of the external DTE/DCE switch.
The figure below shows the location of the DTE/DCE switch on the
PC board, as well as the location of the terminal block and surge
suppressors ("S" model only).
3.1 SETTING THE DTE/DCE SWITCH
For your convenience, the Model 222N has an externally
accessible DTE/DCE switch (see diagram below). If the device
connected to the Model 222N is a modem or multiplexer (or is wired like
one), set the switch to "DTE". This setting causes the Model 222N to
behave like Data Terminal Equipment and transmit data on pin 2.
If the device connected to the Model 222N is a PC, terminal or host
computer (or is wired like one), set the switch to "DCE". This setting
causes the Model 222N to behave like Data Communications
Equipment and transmit data on pin 3.
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DCE
DTE
DCE/DTE
Switch
Surge
Suppressors
(222NS only)
Terminal
Block
DCE
DTE
