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32
Teledyne API – Model T400 O
3
Analyzer
083730400A DCN8130
RS-232
C
ONNECTION
For
RS-232
communications with data terminal equipment (
DTE
) or with data
communication equipment (
DCE
) connect either a DB9-female-to-DB9-female cable) or
a DB9-female-to-DB25-male cable, as applicable, from the analyzer’s rear panel RS-232
port to the device. Adjust the rear panel DCE-DTE switch (Figure 2-2) to select DTE or
DCE as appropriate.
Configuration
: Section Section 3.2.1 and/or Section 3.4.2 (for Hessen protocol).
IMPORTANT
IMPACT ON READINGS OR DATA
Cables can appear to be compatible due to matching
connectors, but their internal wiring can make the link
inoperable. Check cables acquired from sources not from
Teledyne API for pin assignments (Figure 2-9) before
using.
Electronically, the difference between the DCE and DTE is the pin assignment of the
Data Receive and Data Transmit functions.
•
DTE devices receive data on pin 2 and transmit data on pin 3.
•
DCE devices receive data on pin 3 and transmit data on pin 2.
Figure 2-9. Rear Panel Connector Pin-Outs for RS-232 Mode