Signal Levels; Data Lines; Control And Signal Lines - HEIDENHAIN TNC 415 Technical Manual

Physical connections:
Sender
Transmitter
TxD
RxD

2.2.2 Signal levels

The RS-232-C/V.24 interface must differentiate between two different signal lines and their levels.

Data lines:

The data signals are defined as being logic "1" (MARK) over the range -3V to -15V and as logic "0"
(SPACE) over the range +3V to +15V.

Control and signal lines:

These signals are defined as being ON (High) over the range +3V to +15V and as OFF (Low) over the
range from -3V to -15V.
For all of the signals, the voltage range from -3V to +3V is not defined as a logic level and can
therefore not be evaluated.
Datensignale
U [V]
Data signals
+ 15
"0"
SPACE
+ 13
0
– 13
"1"
MARK
– 15
01.98 TNC 407/TNC 415/TNC 425
Übertragungsstrecke
Transmission path
Steuer- und Meldesignal
Control and message signal
HIGH
ON
LOW
OFF
2 TNC data interfaces
Empfänger
Receiver
RxD
TxD
8-11