Tektronix 1705A Car Video System User Manual


 
Maintenance
6-6
1705A Spectrum Monitor
Once communication with the NOVRAM is verified, the microprocessor will
attempt to store data. While attempting to store data, the following message is
displayed on the crt:
READING 2444:
DATA STORED AT 60H TO 7F IN PROCESSOR
If data cannot be stored in the NOVRAM, the following message will be
displayed on the crt:
ERROR : CANNOT STORE DATA
If data cannot be stored, the probable fault is with either the NOVRAM (U812)
or U809 and associated components.
Once the NOVRAM test is successfully completed, there will be an acknowledg-
ing crt display. See Figure 6-3.
END OF NON VOLATILE <2444> RAM TEST:
2444 TEST GOOD
PRESS [INPUT] KEY TO EXIT
Figure 6-3: 1705A CRT display when the NOVRAM Test has been successfully
completed
There is a special case that can occur. In normal operation, the 1705A front-pa-
nel setup should be stored when the power is removed (either turned off or lost
due to power failure) so that it can be recalled when the instrument is powered
up again. If the 1705A does not come back with its previous front-panel setup, it
will provide an error message. See Figure 6-4.