1
2
3
5
4
6
7
This package contains:
•1 Bidirectional Serial/Parallel Converter (SXP-320A or SXP-325A)
•1 AC 9V 200mA Power Adapter
•1 User Manual
Read this guide thoroughly and follow the installation and operation
procedures carefully to prevent any damage to the hub and/or any of the
devices it connects to.
All brand names and trademarks are the registered property of their respective owners.
USER'S MANUAL
Table of Contents
Overview
Features
Installation
Default Configuration
DIP Switch Settings
Cabling
Operation
Appendix
Troubleshooting
Specifications
RS-232C Interface Specification
Centronics Interface Specification
Centronics Interface Timing Chart
Preventing Radio & TV Interference
Overview
The SXP-320A / SXP-325A are interface converters that
allow Centronics and RS-232 devices to communicate
with each other (a computer with an RS-232 output to a
Centronics printer, for example).
Both units are bidirectional enabling you to convert from
serial to parallel or parallel to serial. The primary difference
between them is that the SXP-325A is configured with 512
KB of memory allowing it to serve as a printer buffer,
whereas the SXP-320A has no memory.
These two way converters provide a DB-25 RS-232C (DCE)
compatible connector, and a C-36 Centronics connector.
The serial baud rate is from 1200 to 115200 bps. (selectable
by DIP Switch). The parallel interface speed for the (non-
buffered) SXP-320A is 11.52 KB/sec; for the (buffered) SXP-
325A, it is 1.5 MB/sec.
The units support both hardware and software (XON/XOFF)
handshaking. Setup is extremely easy. All that is involved
is setting the DIP Switch and connecting the cables.
Front View
Rear View
Features
• DIP Switch Sets Data Direction
• Built In Buffer for Efficient Operation (SXP-325A)
• Both Hardware and XON/XOFF Handshaking
• Easy Installation
• Compact Size
Installation
Switch Configuration Overview:
The SXP-320A/325A is configured by setting an eight
segment DIP Switch as follows:
An explanation of each DIP Switch setting is given below.
Note:
1. When the segment is set in the direction of the
arrow, it is ON.
2. In each table, the default setting is highlighted
Conversion Direction:
Cabling
Serial to Parallel:
When performing a Serial to Parallel interface conversion:
1. Plug the female end of a 25/9-pin to 25/9-pin
male/female serial cable into the PC's serial port
2. Plug the male end of the 25-pin to 25-pin male/female
serial cable into the SXP-320A/SXP-325A's serial
connector
3. Plug the female end of a C-36 to C-36 male/female
printer cable into the SXP-320A/SXP-325A's printer
connector
4. Plug the male end of the C-36 to C-36 male/female
printer cable into the printer.
Note:
If your serial cable is long enough, you can plug
the SXP-320A/SXP-325A directly into the printer,
without the need for a printer cable.
5. Plug the Power Adapter into an AC source; plug the
Power Adapter cable into the SXP-320A/SXP-325A's
power jack.
Setting the Switches
Baud Rate:
The baud rate is set with DIP Switch segments 1 - 3, as
shown in the table, below
Handshake:
Data and Stop Bits:
Parity:
Parallel to Serial:
When performing a Parallel to Serial interface conversion:
1. Plug the male end of a 25-pin (male) to C-36 (female)
printer cable into the PC's parallel port
2. Plug the female end of the 25-pin to C-36 male/female
printer cable into the SXP-320A/SXP-325A's Centronics
connector
3. Plug the male end of a 25-pin to 25-pin male/female
serial cable into the SXP-320A/SXP-325A's serial
connector
4. Plug the female end of the 25-pin to 25-pin male/female
serial cable into the printer's serial port
5. Plug the Power Adapter into an AC source; plug the
Power Adapter cable into the SXP-320A/SXP-325A's
power jack.
Switch
Purpose
1
2
Baud rate setting
3
4
Handshake setting
5
Data and Stop Bits setting
6
Parity setting
7
8
Conversion Direction setting
DIP Switch Segment Baud Rate
(bits per second)
1
2
3
ON
ON ON
1200
ON
ON OFF
2400
ON
OFF ON
9600
ON
OFF OFF
14400
OFF
ON ON
19200
OFF
ON OFF
38400
OFF
OFF ON
57600
OFF
OFF OFF 115200
DIP Switch Segment
Handshake
4
ON
XON/XOFF
OFF
Hardware
DIP Switch Segment
Data Bits Stop Bits
5
ON
7
2
OFF
8
1
DIP Switch Segment
Parity
6
7
ON
Either
Parity Inhibit
OFF
ON
Even Parity
OFF
OFF
Odd Parity
DIP Switch Segment
Conversion Direction
8
ON
Parallel to Serial
OFF
Serial to Parallel
SXP-320A / SXP-325A
DCE
DB-25
2
3
4
5
6
20
7
Device Connector's Pin #
DCE DTE DCE DTE
DB-9 DB-9 DB-25 DB-25
2 3 3 2
3 2 2 3
8 7 5 4
7 8 4 5
4 6 20 6
6 4 6 20
5 5 7 7
Cables
a 25-pin/25-pin cable
or a 9-pin/25-pin cable
Tx
Rx
Rx
Tx
RTS
CTS
CTS
RTS
DSR
DTR
DTR
DSR
GND
GND
Device's Pin #
DB-25 C-36
1 1
2-9 2-9
10 10
11 11
12 12
13 13
14 14
15 32
16 31
17 36
18-25 19-30
a 25-pin/36-pinCables
or a 36-pin/36-pin cable
STROBE
D0-D7
ACK
BUSY
PE
SLCT
AUTOFEED-XT
ERROR
INIT
SLCT-IN
GND
SXP-320A / SXP-325A
C-36
1
2-9
10
11
12
13
14
32
31
36
19-30
DIP-SW
PARALLEL PORT
POWER ON LED
AC 9V JACK
RESET KEY
SERIAL PORT
©Copyright 1999 ATEN®
I
nternational Co., Ltd.
Manual Part NO. PAPE -1145-100
Printed in Taiwan 06/1999
PC
9 or 25 Pin Female to 25 Pin Male Cable
36 Pin Female to 36 Pin Male Cable
SXP-320A / SXP-325A
SXP-320A / SXP-325A
25 Pin Male to 36 Pin Female
25 Pin Male to 25 Pin Male Cable
PC
CONVERTER
Serial Port Cabling
Parallel Port Cabling