A3000 Clock Spagetti

clockspagettiThe A3000 I am working on has a few issues, the first was NO CLOCK reported by SYSINFO and other tools. This is of course true, as the battery had been removed after I unboxed this machine. After the battery was removed, the gross damage to the motherboard by the leaking battery is obvious in the picture to the left.

I cleaned the board as best I could, noticed that the back of the board was OK… somehow. I didn’t want to mess with the area around where the battery was, as there was a lot of damage there and I didn’t want to add to it.

I temporarily jumped a CR2032 in a holder (the BLACK and RED leads),  to get get the clock powered. I then went into the Prefs and set the time. After a reboot, the system recognized the clock — but the time had not incremented while the machine was off.

The clock crystal was not outputting anything which ended up being a connection from C192 to R193 was lost. I jumpered them with the BLUE lead. After checking all the connections out I found C190 was not connected either, so i jumpered it with the YELLOW lead.

clocksignalAs opposed to a flatlined output from the Oscillator, I got a signal.

I loaded up the system, reset the time powered it off and waited a few minutes. Turned it back on and the time was in sync. I went out for dinner, had a few drinks and came back — powered it up, clock still working.

I know the clock is not so important in this day and age, as NTP can handle the time sync. But who wants a broken machine?

Next on the list.. Display warm up… sometimes the display shows something, sometimes it takes a few power cycles to get it going…

4 thoughts on “A3000 Clock Spagetti

  1. Um, actually the clock is quite important on the A3000(t) it also stores the scsi information for reselection,synchronous mode and such(it defaults back to async when battery is gone.
    You can reprogram these settings with setbatt_1.2.lha from aminet(search setbatt). and or scsiprefs.lha and scsi-prefs. with a decent drive setting scsi prefs can yield around 5MB/s in synchronous mode(check speed with diskspeed42).

    -Mech-

    • p.s. Please dont put another nicad/nimh varta style battery back on.. use a cr2032 in a coil cell holder with a diode so it cant be charged, the lithium battery will never leak or cause damage.

    • Thanks for the comment, but in the posting I did use a CR2032 :). I used the setbatt to adjust the settings as well. The Battery itself is also protected with a diode and mounted on a plastic tray, to prevent any other problems.

    • if you have an A3000, which versions of the chips do you have? (see newer posts). I’ve been trying to figure out who has the DMAC 02 and Ramsey 07 versions working. If there is a serial number difference etc. Do you have any info on this?

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