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Appendix 3 Interface Specifications
!
RS-232C Interface
Dsub, 9-pin (female)
Pin No.
Signal
Functions
Signal IN/OUT
2
SD (TXD)
Send
data Output
3
RD (RXD)
Receive
data
Input
4
Short with pin 6
5
SG
Signal
ground
6
Short with pin 4
7
CS (CTS)
Ready to send
Input
8
RS (RTS)
Request to send
Output
!
Interface circuits
Output circuit
Input circuit
TXD, RTS
RXD, CTS
Voltage polarity
Logical value
Control level
+
0 (space)
ON
-
1 (mark)
OFF