Overview

Ethernet is the standard local area network (LAN) access method. A reference to "LAN," "LAN connection" or "network card" automatically implies Ethernet. Ethernet is defined by the IEEE as the 802.3 standard. A 10/100 Ethernet port supports two speeds: 10 Mbps (10Base-T) and 100 Mbps (100Base-T).

Regarding serial data, point-to-point connections between two devices usually apply the RS 232 interface. The complete specification for four-wire full-duplex transmission as well as definitions for the handshaking lines are presented in the US standard RS 232C, or in the almost identical international standard ITU-T V.24. RS-232 data are transmitted asynchronously. The RS 422 interface is particularly suitable for fast serial data transmission over long distances. Within a transmission facility, maximum ten RS 422 receivers may be connected in parallel to one transmitter. The RS 422 can be implemented as 2-wire simplex or as 4-wire full-duplex interface. The electrical specifications and the wiring regulations of RS 485 largely correspond with the RS-422 standard. Additionally, RS 485 enables bidirectional bus communication between up to 32 participants. So this interface is frequently used for multi-point connections in field networks. RS 485 can be designed as 2-wire bus or 4-wire full-duplex interface.

In information technology, Universal Serial Bus (USB) is a serial bus standard to interface devices to a host computer. USB was designed to allow many peripherals to be connected using a single standardized interface socket and to improve the capabilities by allowing devices to be connected and disconnected without rebooting the computer (hot swapping). Other convenient features include providing power to low-consumption devices without the need for an external power supply and allowing many devices to be used without requiring manufacturer specific, individual device drivers to be installed.

Many transducers provide an output that is one of two states: high or low, open or closed (closure of a switch). Many types of digital input signals from switch closures, relay contacts, or TTL-compatible interfaces can be read directly by digital I/O cards. The most common type of digital input is the contact closure. Essentially a sensor or switch of some type closes or opens a set of contacts in accordance with some process change. An applied electrical signal then determines whether the circuit is open or closed. Current flows if the circuit is closed, registering a "1" in a transistor at the computer interface. Conversely, an open circuit retains a high voltage (and no current), registering a "0" at the transistor.

Optiva Series - Professional Media Transport

FDV, FMV Series

USB Series

DS Series