COMSPHERE 6800 Series Network Management System
2-110
January 1997
6800-A2-GB31-20
Digital Test (dit)
(Disruptive)
Use the dit command to test the transmitters and receivers in specified DATAPHONE II or
COMSPHERE control and tributary devices, as well as the primary data transmission facility
connecting them. Digital testing of multiple links consisting solely of COMSPHERE devices or
solely of DATAPHONE II devices is supported by this command. Digital testing of multiple links
consisting of a mix of COMSPHERE and DATAPHONE II devices is not supported by this
command.
For APL modems, the control device generates and transmits to the tributary device a
user-specified number of 100K bit blocks comprised of 511 bit pseudo-random sequences. The
tributary loops the blocks back to the control device where they are checked for errors. The test
fails if ten or more errors are detected in one block.
For DATAPHONE II DSUs, a timed test pattern is looped through the tributary DSU back to the
control DSU which checks the received data for errors. If one or more errors are found in the
received test pattern, the tributary DSU fails the test.
For 3600 Series DSUs, a timed 511-bit test pattern is looped through one tributary device and back
to the control device which checks the received data for errors. The total seconds in error and bits
are displayed as test results.
For DATAPHONE II DDD modems, this test causes the specified local modem to send a timed test
consisting of alternating zeros and ones to a remote modem that loops the message back to the
local modem. The local modem checks the message for errors. Five or more errors constitute a
failure.
For most commands, NMS enables you to specify the destination for the command’s results and
schedule its execution. If the last page of the input form cannot accommodate the Destination for
results and Schedule execution fields, an additional page is provided. For a complete description
of these fields, refer to Chapter 1, Introduction.
Access Level:
Data Technician, Manager, System Administrator
Abbreviation:
dit
Alternate: dt
Restrictions:
None
Routine:
Yes
Schedule:
Yes
Related Commands: None
Digital Test Input Form
A common input form is used to request test parameter information for digital test execution to
APL modems, DSUs, and DDD modems. However, within the input form you can specify
information for only a single service class of devices. The digital test is sent to the specified
devices that are of the service class indicated by the test parameter information. A sample Digital
Test input form is shown in Figure 2-29.