Operation
3-6
DDS/MR64
DTE INITIATED TEST SIGNALS
In addition to front panel initiation, tests can also be initiated by the
DTE. The DTE pin numbers used to initialize these tests depend on the
type of DTE interface used and are listed in Tables 3-1 and 3-2. This
section describes sequential signal generation that activates these tests.
Test signals are looped between the DTE, DCE, and the DDS network.
When lit, the TM LED indicates test mode is selected and the LCD
shows the status of the selected test.
Local Line Loopback
LL
When the DTE turns LL on, the DDS/MR64 logic transmitter and
receiver connect internally to loop signals back to the DTE. The
communications transmitter and receiver are also connected to loop
signals back to the DDS communication line.
Remote Terminal Loopback
RT
When the DTE turns RT on, the DDS/MR64 loops data to and from the
DDS line through the DTE interface. A bilateral loopback also provides
a loopback path for connecting the DTE transmit and receive data.
Remote Loopback
RL
When the DTE turns RL on, the DDS/MR64 sends a command to the
remote DDS/MR64 causing it to go into RT loopback. When RL is
turned off, the DDS/MR64 sends a command to the remote DDS/MR64
canceling the RT loopback command.
Test Pattern
TP
When the DTE turns TP on, a 511 bit test pattern is sent to the DDS line.
The data received is scanned for the same test pattern. Any error in the
receive pattern causes the appropriate message to be displayed. If the
DDS/MR64 is in LL when TP is on, the test pattern is transmitted
through the DDS/MR64 transmit logic and looped back through the
DDS/MR64 receive logic. This results in a self test.
Test Mode
TM
When the DDS/MR64 is in either remote or local test mode, TM lights.
Содержание DDS/MR64
Страница 4: ...iv ...
Страница 10: ...Table of Contents x DDS MR64 Appendix A Specifications ...
Страница 14: ...Introduction 1 4 DDS MR64 ...
Страница 18: ...Installation 2 4 DDS MR64 ...
Страница 28: ...Operation 3 10 DDS MR64 ...
Страница 44: ...Configuration 4 16 DDS MR64 ...
Страница 54: ...Troubleshooting 6 4 DDS MR64 ...
Страница 58: ...Non DDS Applications 7 4 DDS MR64 ...
Страница 62: ...Maintenance 9 2 DDS MR64 ...
Страница 64: ...Specifications A 2 DDS MR64 ...