Introduction
26
Model 3088A Series User Manual
2 • Configuration
DCE/DTE operation
Note
This section applies to the following 3088A models:
- 3088A/A - RS-232
- 3088A/CA - V.35
- 3088A/D - X.21
There are a few things to note about clock modes and the 3088A sync serial interface.
-
One 3088A must be set to
Receive-Recover.
The other 3088A must be set to either
Internal
or
External/
Network
clock mode.
-
The 3088A that is configured as
Receive-Recover
must be DCE.
-
The 3088A that is configured as
Internal
must also be DCE, but if it is an
External/Network
clock, then
the modem must be configured as DTE.
ON
OFF
OFF
OFF
ON
ON
ON
4672
ON
OFF
OFF
ON
OFF
OFF
OFF
4736
ON
OFF
OFF
ON
OFF
OFF
ON
4800
ON
OFF
OFF
ON
OFF
ON
OFF
4864
ON
OFF
OFF
ON
OFF
ON
ON
4928
ON
OFF
OFF
ON
ON
OFF
OFF
4992
ON
OFF
OFF
ON
ON
OFF
ON
5056
ON
OFF
OFF
ON
ON
ON
OFF
5120
ON
OFF
OFF
ON
ON
ON
ON
5184
ON
OFF
ON
OFF
OFF
OFF
OFF
5248
ON
OFF
ON
OFF
OFF
OFF
ON
5312
ON
OFF
ON
OFF
OFF
ON
OFF
5376
ON
OFF
ON
OFF
OFF
ON
ON
5440
ON
OFF
ON
OFF
ON
OFF
OFF
5504
ON
OFF
ON
OFF
ON
OFF
ON
5568
ON
OFF
ON
OFF
ON
ON
OFF
5632
ON
OFF
ON
OFF
ON
ON
ON
5696
Table 6. 3088A Clocking
Mode
DTE/DCE
Clock Source
Internal
DCE
3088A Internal Oscillator
Receive-Recover
DCE
Clock recovered from DSL
External
DTE
Clock from external Interface
External
DCE
Clock from external Interface
a
a. For X.21, external DTE must provide clocking on pins 7 & 14.
Table 5. S4-2 through S4-8 Data Rate DIP switch settings (Continued)
S4-2
S4-3
S4-4
S4-5
S4-6
S4-7
S4-8 Data Rate (kbps)
