68kMLA Classic Interface
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| Click here to select a new forum. | | Recapped IIci intermittent clock counting | Posted by: KI5NYZ on 2026-02-19 19:44:21
IIci had very little corrosion and it was isolated to pin 7 of UE13. Cleaned the board and recapped with tantalums from DigiKey. Seller shipped with PRAM battery removed and there is no damage or evidence of the battery having exploded.
The clock was originally working, but now it just stays on the last set time, whether manual or NTP. Snooper says the RTC is working fine, and the set date/time is retained after power cycle or reboot. Using a fresh cr2032 in a MacBatt module.
The mac boots and runs fine. Soft poweron and shutdown/power off works fine. Have disabled all extensions except 'date & time, and alternately with just superclock enabled with no resolution. Google-fu says Y5 or the RTC may be the culprit.
Not able to measure Y5 for a few days. Is there anything else to check for? | Posted by: Boctor on 2026-02-19 22:22:35
AFAIK, whichever crystal is the 32,768hz one, in proximity of the RTC, is its clock source. If it's anything like the SE/30 and IIcx (I think the logic is almost identical but the pinout differs?) then the 1hz source, an interrupt, starts from a leg of that 8-pin RTC. It is completely possible to have it retain PRAM/time but not tick, if something is short/broken on those lines.
When the clock won't tick, does your cursor flicker at unexpected times out of sync with normal vertical blanking, even on an idle desktop? (Not counting applications that damage/repaint constantly and always have to do this, e.g. QuickTime MoviePlayer.) | | 1 |
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