8.2 TNC Data Interfaces
8.2.1 General Information
8.2.2 RS-232-C/V.24 Interface
Hardware
December 2001
The TNC features one of each of the interfaces:
n
RS-232-C/V.24 and
n
RS-422/V.11
The two interfaces differ in the design of their hardware with regard to signal
lines, signal levels and pin layout. The data format and transmission protocol
are the same.
The two interfaces can be operated in parallel.
Three transmission protocols are available:
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Standard transmission protocol
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Transmission protocol with Block Check Character (BCC)
n
LSV2 transmission protocol
RS-232-C/V.24 is the designation for a serial interface. Data transfer is
executed asynchronously, with a start bit before each character and one or
two stop bits after each character.
Transmission distance: up to 20 m
The physical connection between two RS-232-C/V.24 interfaces is an
asymmetrical line, i.e. the common ground connection between transmitter
and receiver is used as a return wire.
Physical connections:
TNC Data Interfaces
8 – 9