Teledyne 300M - Manual (Page 120)

Teledyne API Model 300M CO Analyzer Instruction Manual, 04033, Rev. A
APPENDIX A Tips on connecting the Teledyne
API analyzer RS-232 interface
Teledyne API analyzers use the RS-232 communications protocol to allow the instrument
to be connected to a variety of computer-based equipment. RS-232 has been used for
many years and as equipment has become more advanced, connections between various
types of hardware have become increasingly difficult. Generally, every manufacturer
observes the signal and timing requirements of the protocol very carefully. Problems
arise when trying to specify connectors, and wiring diagrams that attach the analyzer to
various devices.
The problem centers around two areas. First is the physical incompatibility of
connectors. Second is the wiring of the connectors. This Note will attempt to provide
some guidelines for connecting the Teledyne API analyzers to a variety of other
equipment
Connectors:
There are a wide variety of
connectors and cables that are
specified to operate with the RS-
232 protocol. This is because
electronics have decreased in size
over the years and connectors have
been downsized to match the
electronics.
Cables & Adapters come in
4 general types
1. Cables - cables are
provided in various lengths from 6
to 50 feet. In most cases they have
a male connector at one end and a
female at the other. Variations on
this are ones that provide both a
cable and adapter. For example
the cable provided with our
analyzer adapts a female DB-9 to a
male DB-25 connector. Most
cables do not contain a Null
modem.
Pin Signal
1 Not
Used
2 Transmit Data
3 Receive Data
4 Not Used
5 Signal Ground
6 Not Used
7 Data Set Ready (DSR)
8 Request to Send (RTS)
9 Not Used
RS-232 PIN ASSIGNMENTS
FIGURE A.1
2.
Gender changers - convert a male connector to a female connector or vice versa.
They do so WITHOUT changing the pin-to-pin wiring.
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