Switch S1-1 through S1-4
(Model 1185): Async/Sync Data Rate
On Model 1185 Switches S1-1, S1-2, S1-3 and S1-4 set two
parameters: synchronous or asynchronous data rate and the maximum
transmission distance between two Model 1185s.
Data Max
Distance
S1-1
S1-2
S1-3
S1-4 Rate (kbps) in miles (km)
On
Off
Off
On
0-19.2 3.0
(4.8)
On
Off
Off
Off
0-38.4 1.5
(2.4)
On
On
On
Off
2.4 1.5
(2.4)
Off
On
On
On
9.6
3.0 (4.8)
On
Off
On
Off
14.4
1.5 (2.4)
On
Off
On
On
19.2
3.0 (4.8)
Off
Off
On
Off
28.8
1.5 (2.4)
Off
Off
On
On
38.4
3.0 (4.8)
On
On
Off
On
48.0
3.0 (4.8)
Off
On
Off
Off
56.0
1.5 (2.4)
Off
Off
Off
On
64.0
3.0 (4.8)
Off
On
On
Off
72.0
1.5 (2.4)
Off
Off
Off
Off
128.0
1.5 (4.8)
On
On
Off
Off
144.0
1.5 (2.4)
Off
On
Off
On
192.0
1.5 (2.4)
On
On
On
On
256.0
1.5 (2.4)
7
Switches S1-5 and S1-6: Clock Source
Switches S1-5 and S1-6 are set in combination to determine Model
1184 and 1185 transmit clock source.
S1-5
S1-6
Setting
Description
On
Off
Internal
Transmit clock
generated internally
On
On
Internal
Transmit clock
generated internally
Off
On
External
Transmit clock derived
from terminal interface
Off
Off
Received Recover
Transmit clock derived
from the received line
signal
NOTE: Because communication between two Model 1185s is
always synchronous, you must set these switches whether your
application is async or sync. For X.21 or Async applications,
please configure one unit for internal clock mode and the other for
receive recover clock mode.
Switch S1-7: DTE Control of DL
The setting for Switch S1-7 determines whether DTE control of
remote digital loopback test is enabled or disabled. If DTE control is
disabled, the DL test can only be initiated by the front panel switch. If
DTE control is not available, set switch S1-7 to the Off position.
S1-7
Setting
Description
On
Enabled
Respond to DL requests from DTE
Off
Disabled
Ignore DL requests from the DTE
Switch S1-8: DTE Control of LAL
The setting for switch S1-8 determines whether DTE control of
local analog loopback test is enabled or disabled. If DTE control is
disabled, the LAL test can only be initiated by the front panel switch. If
DTE control is not available, set switch S1-8 to the Off position.
S1-7
Setting
Description
On
Enabled
Respond to LAL requests from DTE
Off
Disabled
Ignore LAL requests from the DTE
8
}
}
Async
Settings
Sync
Settings
