User's Manual

Model 1150A DVOR
3-58 Rev. - November, 2008
This document contains proprietary information and such information may not be disclosed
to others for any purposes without written permission from SELEX Sistemi Integrati Inc.
3.6.8.6 Diagnostics Screen
3.6.8.6.1 Power-Up Diagnostics Results
The Power-up Diagnostics Results screen is shown in Figure 3-54. This screen shows the results of the most recent
power-up diagnostics test. Each time any of the navaid’s embedded processors is reset or powered up, it performs a
series of internal diagnostic tests to verify its integrity. The results of those tests are displayed on this screen for the
RMS, Monitors and Audio Generators. CPU Functional tests are instruction and data fetches, bit operations, and
math operations. RAM checks are extensive tests on individual bit positions of all RAM. PROM checks are
checksum calculations and comparison against checksums established at the factory. EEPROM checks are
checksum validations of data held in EEPROM. Green indications are normal. If a module indicates a power-up
diagnostic failure, it should be replaced.
Depending on where in the startup process the fault is detected, failure of the monitor or audio generator will either
stop servicing the watch dog or enter the failsafe shutdown loop.
In the case of the audio generator, either case will result in no radiation.
In the first case for monitor, communications would never be established, and the RMS would remove it from the
LCU voting logic and force the outputs into the alarm state. In the second case for the monitor, the monitor forces a
hard alarm to the LCU and the RMS would remove it from LCU voting logic after the integrity tests failed.
The RMS when failed does not enable the LCU and waits for the watchdog to reset and if the fault does not clear
then the reset continues until the RMS is replaced.
Figure 3-54 Power-Up Diagnostics Results Screen