CTC Union ET100A, User Manual

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ET100A LAN-WAN Bridge
18
When the
ET100A
leaves the factory, all DIP switch settings are set
to the OFF position.
Auto ‐ negotiation:
When this feature is enabled (SW1 ‐ 6=OFF), the Speed (SW1 ‐ 7) and
Duplex (SW1 ‐ 8) settings are ignored and are automatically determined
from the LAN connection. When this feature is disabled (SW1 ‐ 6=ON), the
Duplex and Speed settings of the LAN follow the settings of SW1 ‐ 7 and
SW1 ‐ 8. Use forced mode with caution to avoid Duplex Mismatch.
Protocol Selection:
The
ET100A
supports selecting one of three encapsulation protocols.
When selecting HDLC, the encapsulation is per ISO 13239. The cHDLC
encapsulation is compatible with Cisco® modified HDLC. The PPP
encapsulation follows RFC1661 and is also a very popular encapsulation
protocol. The protocol selection is controlled by the setting of DIP switches
SW1 ‐ 1 and SW1 ‐ 2.
Clock Selection:
The
ET100A
inherently acts as a DTE device. A 1:1 cable is used to
connect to a DCE device such as a modem, CSU/DSU or data multiplexer.
Clock source comes from the DCE so the clock setting is usually external
(SW1 ‐ 4 OFF). The
ET100A
is also capable of acting as a DCE. In this case a
crossover cable is required and clock setting (SW1 ‐ 4 ON) is internal. Data
rate is then set by SW2, 3~9 and ET100A provides clock source.