Zeiss humphrey HFA II-i series, Руководство по обслуживанию на месте

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Humphrey Field Analyzer II - i Troubleshooting
Confidential and Proprietary
52235C1105 5 - 13
Field Service Guide
5.7 Power-On Self Tests
5.7.1 Motor Driver Board Startup
The startup of the Motor Driver Board involves eighteen distinct operations, each of which
must succeed before the Motor Driver Board is deemed to be operating successfully and
capable of supporting clinical testing activity.
The Motor Driver Board startup sequence is outlined in the steps below. Recommended
repair actions are described in Section 5.8.
Step 1 Resets Motor Driver Board
Sends NMI signal to Motor Driver Board, then waits until CTS is true. Bowl intensity is at
maximum value.
Step 2 Gets ROM revision level
Checks the revision level to see whether loader or motor controller code is running, and to
ascertain that it is at an appropriate level with the desired functional support.
Step 3 Gets ROM status
Reads the status of the Motor Driver Board ROM startup, to ascertain if the self-check
succeeded.
Step 4 Resets motors
Brings all six motors to their respective flag crossings.
Step 5 Sets internal variables for operation.
Sets internal variables using a white stimulus against a white bowl.
Step 6 Initializes calibration constants
Data is read from NVM, and internal variables are populated. This includes offsets for the X,
Y, F, and S motors, bowl and projector intensities, aperture wheel calibration values, gaze
window location, eye monitor parameters, eye illumination parameters, and the gaze
calibration parameters.
Note ­
all parameters have reasonable default values in case of initial power-up or un-
calibrated system.
Step 7 Turns on the projection lamp to allow for lamp warmup.