Crown XLS 1000 Series, Руководство по обслуживанию

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APPENDIX B: XLS-3 LCD TROUBLESHOOTING:
Affects:
141673-x PWA, XLS DISPLAY 1000
141558-x PWA, XLS DISPLAY 1500/2000/2500
New functionality has been added to firmware version 1.1.2.2 that allows for more
simplified troubleshooting of issues relating to the LCD. If troubleshooting an LCD on
an audio processing module (APM) with older firmware, it is suggested to update the
firmware to at least 1.1.2.2 before continuing. Please refer to the service manual for
instructions on updating firmware.
At bootup, the updated firmware initializes the LCD. Then the microcontroller writes to
the registers in the LCD module and attempts to read them back. If there are no issues,
the amp will continue booting. Otherwise, there are two possible error codes relating to
the LCD that are:
MAJOR MINOR ERROR COMMENT
1 1
LCD POST Fail Initialization of LCD failed
1 2
LCD Communications Fail MCU unable to communicate
with LCD. Can occur
anytime as opposed to POST
These error codes are unique and based upon a Major and Minor element. The Major
element is determined by which portion of the amplifier failed POST, while the Minor
portion is which part of the Major element failed. They are displayed by CH1 Thermal
LED = MAJOR, CH2 Thermal LED = MINOR. The MAJOR is blinked 1st, then the
MINOR. Other symptoms may be observed like a row of solid squares in the LCD.
This procedure was developed in order that the board could be troubleshot with an
oscilloscope and one probe. It will be necessary to probe the signals on the LCD header.
If a test fixture is available to power the APM outside of the amplifier, this is probably
recommended for ease of probing the different pins on the header. However, it can be
troubleshot inside the amplifier. Below is a figure to help identify pin one of the LCD
header in either case.