Patton electronic 2073 - Manual (Page 5)

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3.1.2 Configuration DIP Switch Set “S2”
Switch S2-1: Clear Channel or Octet Timing Mode
Use Switch S2-1 to control the G.703 timing mode. When S2-1 is
set to the “Off” position, a clear channel mode of operation is select-
ed. In this mode, only user data is transmitted to and from the DTE
interface at any one of the data rates mentioned in section 3.1.1.
When S2-1 is set to the “On” position, 128K octet timing mode is
selected. In this mode 64 kbps octet timing information is embedded
within the 64 kbps user data, thus creating a 128 kbps synchronous
data stream to and from the DTE.
NOTE: Octet timing mode requires synchronous, 128 kbps DTE operation.
When octet timing mode is selected (S2-1=”On”), all data rate selection switch-
es are ignored.
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Switches S1-5 and S1-6: Transmit Clock Source
Use Switches S1-5 and S1-6 to configure the 2073 transmit clock
source. In campus applications, in which two Model 2073s operate as
short range modems, set one unit for internal or external clock, and the
other unit for Network (Campus) Clock. When the Model 2073 termi-
nates a 64kbps G.703 line and provides a serial interface to customer
premises equipment, set the unit for Network (Normal) Clock.
NOTE: Switches S1-5 and S1-6 determine the source of clocking across the
G.703 connection. Therefore, this option must be defined in both
Asynchronous and Synchronous DTE applications. External transmit clock
source is not a valid setting for asynchronous applications.
Switch S1-8: Local V.54 Preparatory Phase Reception
Enable/Disable
Use switch S1-8 to control the reception of the V.54 remote digital
loopback preparatory phase bit pattern by the local Model 2073. When
this switch is “On”, the local 2073 will respond to any V.54 loopback
requests that are received from the G.703 network. This is the normal
setting. This setting will allow the local Model 2073 to enter V.54 loop-
back when a valid V.54 preparatory phase bit pattern is received from
the G.703 network.
When S1-8 is “Off”, the local Model 2073 will ignore any V.54 loop-
back requests that are received from the G.703 network. This mode
can be used to prevent the local Model 2073 from entering V.54 loop-
back mode indadvertently, due to bit streams that resemble the V.54
preparatory phase pattern. Even if S1-8 is “Off”, the local Model 2073
may still initiate a V.54 loopback request.
Clear Channel or Octet Timing Mode S2-1
Clear Channel Mode Off
Octet Timing Mode On
V.54 Prep Phase Reception S1-8
Disabled Off
Enabled On
Transmit Clock Source S1-5 S1-6
Internal Off Off
External Off On
Network (Normal) On Off
Network (Campus) On On
Position Function Factory Default
S2-1 Timing Mode Off Clear Channel
S2-2 BPV Transmit Control Off BPV not inserted
S2-3 Front Panel Switch On Enabled
S2-4 DTE Test Mode On Acknowledged
S2-5 Reserved Off
S2-6 Reserved Off
S2-7 Reserved Off
S2-8 Reserved Off
S2 Summary Table