A2.2 Rs-232 Standard - ICS ELECTRONICS 4863 Manual

A2.2 RS-232 STANDARD

In 1963, the Electronic Industry Association (EIA) established a
standard to govern the interface between data terminal equipment and
data communication equipment employing serial binary interchange.
The latest revision of this standard (RS-232) has been in effect since
1969 and is known as RS-232C. It specifies:
The specification does not mean that two devices that are RS-232
compatible can be connected together with a standard cable and
be expected to work.
Mechanically, RS-232 interfaces use a 25 pin male connector (DS-
25P) with the data terminals and a 25 pin female connector (DS-25S)
with the data communications units (modems).
A2
Electrically, RS-232 signals are bipolar and are referenced to a
common ground (AB) on pin 7. Transmitted signals must be between
+ +
5 and
open circuit transmitter outputs is ±25V. Logic levels are:
- Mechanical characteristics of the interface
- Electrical characteristics of the interface
- A number of interchange circuits with descriptions of their
functions
- The relationship of interchange circuits to standard interface
types
15V or -5 and -15V into 3000 to 7000 ohm loads. Maximum
+5 to +15V
Data
Control 1 (On)
-5 to -15V
0
0 (Off)
A-22
1