Can I add a modern battery solution to my 2/10 to hold time and "date"?
Quote from: bmwcyclist on February 22, 2026, 02:47:56 PMCan I add a modern battery solution to my 2/10 to hold time and "date"?
In the late '80s Dafax was selling a made-to-order COPS battery backup for the 2/10, but I never saw one. It used NiCd like the ones that leak in the 2/5.
IIRC, the 10 pin header on the 2/10 I/O Board has the +5 Standby voltage, but no ground, so there isn't a really trivial way to connect it.
As long as the Lisa is connected to AC power, the time should be retained, so if using a power bar to eg. turn off peripherals, perhaps you can power the Lisa separately.
Quote from: sigma7 on February 22, 2026, 05:35:20 PMso there isn't a really trivial way to connect it.
As long as the Lisa is connected to AC power, the time should be retained, so if using a power bar to eg. turn off peripherals, perhaps you can power the Lisa separately.
Thanks!
As sigma7 said, the Lisa RTC depends on the Lisa being plugged-in to AC power. The battery backup on the original IO board will only maintain the time for up to 10 hours. If you had a minor power outage or just un-plugged your Lisa to move it to another room this worked well. If you unplugged your Lisa at the end of the day, and plugged it in the next morning, the batteries would be dead and your clock was reset. It seemed like Apple recognized this was pretty useless and they removed the batteries from the 2/10 IO board.
Rick
It is surprising that the Lisa's clock required so much power. The Macintosh 128k used one 4.5v 600mAh battery and kept the time for much longer (1-2 years?) when unplugged.
Quote from: ried on February 23, 2026, 09:13:36 PMIt is surprising that the Lisa's clock required so much power. The Macintosh 128k used one 4.5v 600mAh battery and kept the time for much longer (1-2 years?) when unplugged.
Yes, I was hoping a stack of coin cells would be a safe and usable replacement.
Quote from: ried on February 23, 2026, 09:13:36 PMIt is surprising that the Lisa's clock required so much power. The Macintosh 128k used one 4.5v 600mAh battery and kept the time for much longer (1-2 years?) when unplugged.
A Macintosh has an integrated RTC chip that needs a couple of microamps. The Lisa uses a COPS4 microcontroller that does not provide any significant power saving features.