Lenze Global Drive PLC Developer Studio - Manual (Page 8)

LenzeFpiDrv.lib function library
General information about the RS−232C interface
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LenzeFpiDrv.lib EN 1.1
2 General information about the RS−232C interface
RS−232C stands for Recommended Standard−232C, which is an American Standard of the EIA
(Electronic Industries Association). It describes the serial connection between a DTE (Data Terminal
Equipment) and a DCE (Data Communications Equipment) and all the electrical and mechanical
features.
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The RS−232C is often also described by the V.24/V.28, which is the international
recommendation of the CCITT (today knows as ITU − International Telecommunication Union).
The V.24 specifies the mechanical features and the V.28 the electrical features.
Although the standard RS−232C only describes the connection between a DTE and a DCE, the
RS−232C interface has been established as standard for serial data transmission over short
distances.
The following chapters inform about the mechanical and electrical features of the RS−232C interface
and the serial data transmission.
2.1 Mechanical features
2.1.1 Types of plug−in connectors
In general subminiature−D−plug−in connectors in 9 or 25−pole design are used as interface
connectors. They are distinguished as follows:
Master
(e. g. Lenze PLC with FP interface)
Slave
9−pole SubD connector (male)
or
25−pole SubD socket (female)
9−pole SubD socket (female)
The FP interface requires a connection cable with a 9−pole SubD connector (male).
2.1.2 Terminal assignment with a FP interface
9−pole SubD socket for RS−232C interface
Pin Designation Input/output Explanation
1 − − not used
2 RxD Input Receive data
3 TxD Output Send data
4 DTR Output no function (logic 0")
5 GND − Reference potential
6 DSR Input no function
7 − − not used
8 − − not used
9 + 5V − max. output current 50 mA