Step-by-step installation instructions:
Note: Before installing the card into the computer, we to recommend note down the card
serial number for the event of contacting technical support (see figures in the
Appendix II) . You can note the number in the table at the beginning of this manual.
1) Power off the PC and all peripheral devices.
2) Disconnect the power supply cord and other lead-in cables connected to the
peripheral devices; only devices without power supply can stay connected.
3) Remove the PC´s cover and slot cover bracket if there is one.
4) Check Appendix II and configure PCIe card DIP switches as necessary.
5) Insert the card firmly into a free PCIe slot (x1 - x16) and secure it in place by a screw.
6) In the case of a four-port COM card, fasten the expansion card into next position and
connect the ribbon cable to the COM card.
7) Replace the PC´s cover and connect all cables and power supply cord.
3.5. Location of Connectors, LEDs and Switches
The location of switches, jumpers and LEDs and connectors may be found in the Appendix
II of this manual; each of these elements is explained in the information listed above.
3.6. Connector Pin Assignment
The connector pin assignments are shown in Table 3. and Table 4., and the RS-422/485
interface circuits are shown in Figure 4. and Figure 5. in Appendix II of this manual.
3.7. Topology & Cable Recommendations
The RS-232 line uses a shielded cable, without any termination resistors.
The RS-422/485 communication line is realized by a cable conforming the EIA-RS-485
standard (i.e. shielded pair, conductor cross-section at least 0.22 mm2, impedance 100÷130
Ohm, line capacitance approx. 60 pF/m). Recommended type is Belden 9841.
The recommended arrangement for RS-422 and RS-485 is a connected series of
point-to-point (multidropped) nodes, a line or bus (stubs up to 1 m), up to 1200 m length
(for transmittion rates up to 1 MBd). See Figure 6. and Figure 7.
Ideally, the two ends of the cable will have a termination resistor connected across the two
wires. Typical value is 120 Ohms for twisted pairs. At least one of the terminators should
have active topology (the so-called terminator with failsafe bias resistors), when using
RS-485 or RS-422 multimaster (four-wire RS-485).
The maximal number of the devices at one RS-485 communication line is 32. If you need to
use more devices than 32, the repeaters can be used to divide the network into several
segments - see Figure 8. Each segment should meet the requirements listed above. The
repeater is considered as one of the 32 devices. Although the number of the repeaters in a
row is not limited, more than three are not generally recommended.
Note: The TEDIA®product line provides a complex series of isolated converters, and
repeaters for the RS-232, RS-422 and RS-485 lines.
PCI Express Communication Cards User Guide
rev. 10.2009 I - 5
