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: M 1 IC-485S or IC-485SI Interface Converter M 1 Power Adapter (DC 9V; 300mA) M 1 User Manual If anything is damaged or missing, contact your dealer. © ® Copyright 2005 ATEN International Co., Ltd. Manual Part No.
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.
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.
Switch Configuration The IC-485S / IC-485SI’s operating mode parameters are set with two slide switches: M SW1 sets the Device Mode M SW2 sets the Transmitting and Receiving Mode IC-485S Switch Settings SW 1 RS-232 DB-25 Female Connecter SW 2 Terminal Block Spare Power Jack RJ-11 Setting Position SW1 SW2 1 DCE TxO, RxON 2 DTE TxRTS, RxRTS 3 Monitor TxRTS, RxON -2- 2005-01-04
IC-485SI Switch Settings SW 1 RS-232 DB-25 Female Connecter SW 2 Terminal Block Power Jack Grnd.
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.
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.
2. Point-to-Point 2 Wire Half Duplex M Point-to-Point Half Duplex uses straight through four wire cabling, as shown in the diagram below: DB-25 Connect to PC#1's COM port DB-25 T+ TRR+ R+ RTT+ Connect to PC#2's COM port M For both IC-485S / IC-485SI units, set SW1 to DCE or DTE depending 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). M For both IC-485S / IC-485SI units, set SW2 to TxRTS, RxRTS.
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.
2. Multidrop Half Duplex M Multidrop Half Duplex uses straight-through four wire cabling, to link all the connected IC-485S / IC-485SI units: PC1 COM1/ COM2 Slave 1 R+ RTT+ Master T+ TRR+ Slave 2 R+ RTT+ Slave 3 R+ RTT+ . . Slave 31 PC2 COM1/ COM2 PC3 COM1/ COM2 PC4 COM1/ COM2 M For all IC-485S / IC-485SI units, set SW1 to DCE or DTE depending 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).
Simplex A Simplex configuration is one in which more than two devices are linked for communication using several IC-485S / IC-485SI units in a manner similar to Multidrop. The difference is that in a Simplex configuration, the Master device can only talk, and the Slave devices can only listen.
Monitor (IC-485S only) With Monitor Mode, the RS-485S can be wired to the lines of an RS-485 or RS-422 device to monitor the line signals. In this configuration, the RS-485S changes the functions of T+ and T- to R’+ and R’- respectively. Device 1 T+ TRR+ Device 2 R+ RTT+ IC-485S T+ (R'+) T- (R'-) RR+ PC COM1/ COM2 M Set SW1 to Monitor. M Set SW2 to TxRTS, RxON Note: 1. The RTS must be Low in Monitor Mode. 2. The R+ and R- signals are converted and linked to the RS-232 port, DB-25 pin 3.
Installation 1. Set each IC-485S / IC-485SI’s configuration switches according to the information provided in the Switch Configuration and Operating Modes sections. 2. Plug the IC-485S / IC-485SI’s DB-25 female connector into the computer’s RS-232C port. 3. Connect the IC-485S / IC-485SI units to each other: M Use two or four wire twisted pair cable in a reverse or straight through configuration according to the information provided in the Switch Configuration and Operating Modes sections.
Appendix The Terminal Block The four screw terminal block has different pin assignments depending on the operating mode: M In DCE/DTE mode, terminals 1 (+V) and 2 (-V) are configured to transmit data (the transmitter); while terminals 3 (-V) and 4 (+V) are configured to receive data (the receiver). M In Monitor mode (IC-485S only), terminals 1 and 2 are, respectively, the positive and negative of receiver 1; while terminals 3 and 4 are, respectively, the positive and negative of receiver 2.
DCE / DTE Connection Table Because of the polarity of the communication signals, a DTE configured device must connect to a DCE configured device.
Troubleshooting Problem Data Transmission Failure Action Check that the power adapter is plugged in and working properly. Check that the IC-485S / IC-485SI units are securely plugged into the computers’ serial ports. Check that the cables are properly set up and properly connected. Check that SW1 and SW2 are set properly. Data Loss or Error Check that the Data Rate and Data Format are the same for all devices.
