Black Box ME260A, Owner'S Manual

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21
CHAPTER 2: Introduction
2.3.3 I
NTERFACING WITH
64-
KBPS
C
O
-
DIRECTIONAL
I
NTERFACE
M
ODULE
(ME266C)
Figure 2-9 shows a typical interface-signal flow diagram for an interface-converter
application that uses a 64-kbps co-directional interface module in conjunction with
a general-purpose interface module. This application allows the transfer of data to
and from the DTE through a 64 kbps line.
In this application, the mode jumper of the UCI interface module connected to
the DTE must be set to the DCE position. The DTE must use external timing. The
jumper of the 64-kbps co-directional interface module is set in accordance with the
system timing requirements:
• LBT—used to lock the DTE timing to the recovered lock signal. This setting
is suitable for “tail-end” applications, where the DTE is connected through
the Modular Modem Eliminator to a data network that includes an accurate
timing source.
• INT—used to lock the DTE timing to the internal clock source of the 64-kbps
co-directional interface module.
Figure 2-9. 64-kbps codirectional module (interface-converter application).
Transmit
Circuits
64 kbps
Codirectional Interface
Internal
Oscillator
Receive
Circuits
J1
Receive
Line
Transmit
Line
DCE Mode
DTE
External Clock
Carrier Detection
Recovered
Clock
TC
TD
RTS
RC
RD
DCD
DSR
DTR
CTS
PG
SG