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Old 03 August 2011, 19:37   #1
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time clock prob a2000

I have an a2000 that can't keep,,, time past july 19 2011. The battery has been replaced. I go into prefs and change the time and can save it. Warm resets are ok, and the correct date is kept, when i turn it off, and turn it on nextvtime the clock is reset to july 19 2011. I don't know if therevis an easy fix or not, but any help would be greatly appreciated.
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Old 04 August 2011, 06:04   #2
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Seems like the RTC chip is duff.
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Old 04 August 2011, 11:41   #3
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Did you already verify that the battery voltage is present at the RTC when mains power has been turned off?
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Old 05 August 2011, 00:59   #4
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No I didn't check at the rtc. I am not sure which chip is the clock. It is a 6.2 revision mobo if it is different than a 4.x. which pins do you check voltage at. Thanks for the reply. I thought that if there was a power fault, the clock would reset to 1978.

Last edited by source; 05 August 2011 at 01:25. Reason: adding without another post
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Old 05 August 2011, 02:20   #5
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Maybe it has hanged and is stuck at that date. Have you tried setting it to an earlier date than todays date?

RTC seems to be an OKI 6242B, U65


Perhaps the oscillator circuit isn't working on pins 16 and 17, or the circuit is broken, sometimes you can find these on expansion memory for the A500 as well. Perhaps the write signal isn't working...

It's not unusual for these old things to have the battery leak and damage traces at the circuit.

If it looses power completely long enough (cap/caps also discharged) it should start at 1978 AFAIK.


Anyway, you check the voltage between pin 18 (+) and pin 9. The chip is probably close to the battery.
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Old 05 August 2011, 04:40   #6
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I have set it to an earlier date and with it powered down for ten min, kept the new time. I will keep it powered down for longer. July 19 2011 is not a special date like y2k for wintel?
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Old 05 August 2011, 15:34   #7
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Could be something wrong with the chip that makes it stuck at that particular time, I'll check mine and see what it says...

Here's a new chip if you want to try and swap:
http://asb-computer.com/shop/product...c549b6e4f74a1b
... and here, and probably the stores selling the ACA 1230 card:
http://amigakit.leamancomputing.com/...6&currency=USD

If it counts up as usual from the earlier time then the circuits and signals around it are probably OK and it is more likely that it's the chip that malfunctions.

EDIT:
My A2000 says todays date and time, only other thinkable option is that it is a software error, perhaps you can boot a diskette with another version of Workbench and check the date from that instead of loading from the harddrive...

Last edited by e5frog; 05 August 2011 at 16:05.
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Old 05 August 2011, 17:21   #8
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perhaps that's when system was installed. iirc, when clock doesn't work, it takes date from most recent dir or file on sys:
or something like that
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Old 05 August 2011, 18:32   #9
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If the RTC chip doesn't work at all then it shouldn't change at all between restarts unless you have saved a file - or does something else jump in and take over the time keeping?
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Old 05 August 2011, 21:25   #10
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Quote:
Originally Posted by orange View Post
perhaps that's when system was installed. iirc, when clock doesn't work, it takes date from most recent dir or file on sys:
or something like that
The date the boot volume was formatted.

One option might be to do a setclock reset, then set the time and do a setclock save.. See if that helps it.
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Old 07 August 2011, 01:58   #11
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I pulled the computer appart andgot the multi meter on it again. When powered u I was getting 5 volts when I turned it off, it dropped to 1.5 volts. And slowly dropped down to.
0.3 volts. The battery was snookered. Wirh the battery off i am getting 5 volts. With the new battery installed, it reads 4.02 volts at the mobo where the battery is attached as well s at the clock chip. With the computer off all day, it seems to be holding time. I now have to solder the new battery and put it back together. I will take photos this time. What threw me off was the clock did no go back to 1978. When it booted from the harddrive, it would set the clock to july 19 2011 2:44pm. When I booted from workbench 3.1 floppy it would set itself to 1994.

Thanks for all the .input
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Old 07 August 2011, 14:16   #12
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As you see, it is set to the date the boot volume was formatted, if the battery backed up clock is not found or has corrupted contents.. :-)
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