TANGO55/i & TANGO56/i User's Manual
Version 1.05
2.6 Determining the External Equipment Type
Before you connect the DB9 serial port connectors on the aforementioned terminals
(DCE units) to external equipment, you need to determine if the external hardware
serial ports are configured as DTE or DCE.
The terms DTE (Data Terminal Equipment) and DCE (Data Communications
Equipment) are typically used to describe serial ports on devices. Computers (PCs)
generally use DTE connectors and communication devices such as modems and
DSU/CSU devices generally use DCE connectors. As a general rule, DTE ports
connect to DCE ports via straight through pinned cables. In other words, a DTE port
never connects directly to another DTE port. Similarly, a DCE port never connects
directly to another DCE port. The signalling definitions were written from the
perspective of the DTE device; therefore, a Receive Data signal becomes an input
to DTE but an output from DCE.
TANGO55/i and TANGO56/i are designed for use as a DCE unit. Based on the
aforementioned conventions for DCE-DTE connections it communicates with the
customer application (DTE) using the following signals:
TANGO55/i and TANGO56/i
Terminal (DCE)
to
Application (DTE)
TxD
◄-----------------------
TXD
RxD
-----------------------►
RXD
RTS
◄-----------------------
RTS
CTS
-----------------------►
CTS
DTR
◄-----------------------
DTR
DSR
-----------------------►
DSR
DCD
-----------------------►
DCD
RING
-----------------------►
RING
Table 7:
The signaling definitions between DTE and DCE.
This confidential document is a property of FALCOM and may not be copied or circulated without previous permission.
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