I know the interwebs are full of information relating to the replacement of batteries for various computers, and the Amiga's are no different. But before I do anything rash, I wanted to ask for some input.
My A3000 still has the original clock battery on the mainboard, and obviously this needs to be removed and replaced.
I thought I was going to replace this with a CR-2032 watch battery socket so I would be able to replace the battery when necessary. This easy ebay solution looked promising... However I noticed the original component is clearly labeled 3.6v and 60mAh (milli-ampere-hours).
A CR2032 is rated at 3v but should last ~200mAh. Is the CR2032 a good replacement choice, or will the lower voltage cause any unexpected weirdness? And what kind of battery-life can I expect? I've got some 486SX/25 mobo's from forever-ago and I swear the CR2032's are still working...
Finally, and perhaps most importantly I was a little freaked out when I read this:
A special note for A3000 users: The RTC has a small amount of memory also backed up by the battery which is used to store settings for the motherboard SCSI controller. After replacing the clock battery, you will need to use SetBatt-1.2 from Aminet.
Usage: SetBatt A
This clears the "amnesia" bit. The SCSI controller settings may also have been lost due to the power interruption to the RTC and may need to be altered depending on your SCSI devices.
- taken from this guide
My concern stems from the fact that my A3000 has the original beta Kickstart 1.4 ROM which it uses to boot the actual Kickstart image from the SCSI hard drive (Kickstart.rom). The absolute last thing I want to do is disconnect the on-board battery for a few days and loose something vital to my ability to boot off the SCSI drive.
Can anyone offer any further details?
As always, all input is greatly appreciated!
Addendum
After reading the excellent responses below, I took the time to re-assemble my Amiga and downloaded SCSIPref from Aminet so I could double check my current settings. As expected, all values were defaults.
I also took the time to put together a few 'rescue' disks with things like SCSIPref, JRComm, and other essentials (SuperKickstart 1.3/3.1) just in case I have to do anything weird after replacing the battery.
Finally, I took some voltage readings off the battery while the charging circuit was both powered and unpowered to (attempt) to properly size a Schottky diode for reverse current protection. I'm going to solder the CR2032 holder right to the motherboard.
Thanks again for the help!