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Chapter 5. Handling the CU-7000 (Option)
[ 2 ] Interface Cable Connection
As illustrated below, connect the CU-7000 (on which the BHT is put) to a host computer
with a cross-mode cable. To connect it to a modem, use a straight-mode cable.

DTE and DCE

In the RS-232C interface specifications, the DTEs (Data Terminal Equipment) shall be
generally connected with each other by a cross-mode cable; the DTE and DCE (Data
Circuit-terminating Equipment) shall be connected with each other by a straight-mode
cable.
The DTE is one piece of equipment connected at both ends of a communications line
as a sender or receiver of data (such as CU-7000 on which the BHT is put and a host
computer).
The DCE is one piece of equipment connected to the intermediate point between the
DTE and the communications line. It terminates communications lines and exchanges
information between those lines without any change in contents (such as modem).
CU-7000
(DTE)
1
2
3
4
5
6
7
8
20
SD
FG
RD
RS
CS
DR
SG
CD
ER
Host Computer
(DTE)
Cable Connection between CU-7000 and Host Computer
CU-7000
(DTE)
Cable Connection between CU-7000 and Modem
Modem
(DCE)
1
4
5
6
7
20
SD
FG
RD
RS
CS
DR
SG
CD
ER
2
3
8