VARILITE VL4 - Data Loop-Back Test (Test 25); Program Modes (Tests 30 through 39); Error History (Tests 40 and 41)

C
HAPTER
3. M
AINTENANCE
P
ROCEDURES
3-7
02.9628.0010 CONFIDENTIAL
7-Oct-97
3.1.4.5 Data Loop-Back Test (Test 25)
The data line test requires an external link between broadcast and reply
lines if the parameter setting is set to 9. On parameter setting 8, the test
will loop back via board relay. A valid loop is indicated by a chasing single
segment circle. Receive and transmit errors are represented by "r" and "t",
respectively, on the display. A transmit error will occur if the MPCC fails
to receive a clock from the Manchester encoder. A receive error will occur
if the MPCC fails to receive a transmitted data package.
3.1.5 Program Modes (Tests 30 Through 39)
The purpose of the program mode is to provide the facility for operating
any choice of mechanisms at individually selected speeds. The selected
mechanisms, with their respective speeds, may then be assigned to a
thumbwheel setting in the range 31 thru 39. These programmed selections
remain valid so long as the test EPROMs are not removed (not corrupted
on power down/up).
The program mode is entered via thumbwheel setting 30. Once entered,
the program mode is indicated by a "P." Tests are now selected or
deselected on a toggle basis. Indication or selection is twofold - the test
can be visibly seen to start and the test number is indicated on the display.
Deselection is indicated by the test stopping and the test number on the
display flashing. Only tests 1 thru 11 are valid in this mode. An illegal test
number is indicated by "P" reappearing on the display. The program mode
is exited by selecting a program save channel, numbers 31 thru 39. "PR"
appears on the display and test continue to run in the mode now selectable
by the parameter digit (synchronized or unsynchronized). Error codes are
indicated for all the tests running since the program was exited. Errors
detected before saving the program mode are cleared, but do go to the
error history list. The save channel number can now be left to return to
running test in manual mode. On return to that number, the
preprogrammed test sequence can be resumed. Error codes indicated will
be those encountered since the rerun of that program.
3.1.6 Error History (Tests 40 and 41)
The error history retains a finite list of all error codes produced since the
test EPROMs were inserted or the list has been cleared. Approximately
120 errors may be saved before the store is considered full. At this point,
the list is cleared. The error history is displayed by accessing test number
40. The list is cleared by accessing test number 41. Test results are not
saved to the history list.