User Manual

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ACB-ULTRA.LPCI User Manual

RS-530 / 530A

RS-530 (a.k.a. EIA-530) compatibility means that RS-422 signal levels are met, and the pin-out for the

DB-25 connector is specified. The EIA (Electronic Industry Association) created the RS-530 specification

to detail the pin-out, and define a full set of modem control signals that can be used for regulating flow

control and line status. The major difference between RS-530 and RS-530A lies in some of the modem

control interface signals. In RS-530 the signals all of the modem control signals are differential, in RS-

530A some of these signals are single ended. The RS-530 specification defines two types of interface

circuits, Data Terminal Equipment (DTE) and Data Circuit-Terminating Equipment (DCE). The Sealevel

Systems adapter is a DTE interface.

V.35

V.35 is a standard defined by ITU (formerly CCITT) that specifies an electrical, mechanical, and physical

interface that is used extensively by high-speed digital carriers such as AT&T Dataphone Digital Service

(DDS). ITU V.35 is an international standard that is often refereed to as Data Transmission at 48 Kbps

Using 60 - 108 KHz Group-Band Circuits. ITU V.35 electrical characteristics are a combination of

unbalanced voltage and balanced current mode signals. Data and clock signals are balanced current mode

circuits. These circuits typically have voltage levels from 0.5 Volts to -0.5 Volts (1 Volt differential). The

modem control signals are unbalanced signals and are compatible with RS-232. The physical connector is

a 34 pin connector that supports 24 data, clock and control signals. The physical connector is defined in

the ISO-2593 standard. ITU V.35 specification defines two type of interface circuits, Data Terminal

Equipment (DTE) and Data Circuit-Terminating Equipment (DCE). The Sealevel Systems adapter is a

DTE interface.