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Gemini G3 - User Manual
15
3.2 DTE Port Interface
For all three ports, we recommend the use of a shielded 9-wire cable with all pins connected. These
ports can be used for unit configuration, maintenance, & adjustment as well to connect user applica-
tions.
Table 3 - DTE port pin functions
DE-9 F pin #
Function
1
DCD – from
GeminiG3
, normally asserted
2
RXD – data from
GeminiG3
3
TXD – data to
GeminiG3
4
DTR – to
GeminiG3
, handshaking
5 Ground
6
DSR – from
GeminiG3
, tied to VCC through current limiting resistor
7
RTS - to
GeminiG3
, handshaking
8
CTS – from
GeminiG3
, handshaking
9
AUX - auxiliary input to
GeminiG3
3.2.1 RS-232 Interface Signal Levels
In the descriptions of data signals, the following conventions are used:
Table 4 - RS-232 Signal Levels
Term
Alternates
Signal level
ON
asserted, spacing
+3 to +15 V
OFF
dropped, marking
-3 to -15 V