CALENDAR ERROR: Difference between revisions

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(Created page with "thumb ==Cause== The RTC's time pulse is too slow or too fast. It should be no less than 57 frames (0.963s), and no more than 64 (1.081s). Ca...")
 
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* Check 32768Hz crystal
* Check 32768Hz crystal
* Check {{Chipname|uPD4990}} traces, especially pin 11 ({{Sig|TP|TP}}) and pins 5, 6 and 7.
* Check {{Chipname|uPD4990}} traces, especially pin 11 ({{Sig|TP|TP}}) and pins 5, 6 and 7.
* ...
* Check {{Chipname|74HC32}} and traces to {{Chipname|uPD4990}}
* Try to reset Backup RAM content:
** Either remove battery
** Or flip all dip switches to on and then power on the board. Then turn off the board and return all dips to normal settings
* You can use unibios to skip this error


[[Category:Repairs]]
[[Category:Repairs]]

Latest revision as of 12:27, 29 April 2018

Cause

The RTC's time pulse is too slow or too fast. It should be no less than 57 frames (0.963s), and no more than 64 (1.081s).

Can happen if traces are cut.

Suggestions

  • Check 32768Hz crystal
  • Check uPD4990 traces, especially pin 11 (TP) and pins 5, 6 and 7.
  • Check 74HC32 and traces to uPD4990
  • Try to reset Backup RAM content:
    • Either remove battery
    • Or flip all dip switches to on and then power on the board. Then turn off the board and return all dips to normal settings
  • You can use unibios to skip this error