[colug-432] SPARC "EEPROM" Battery Replacement

[Bill Schwanitz]

Ricky assuming you even want  to try this - 
http://www.memoryxsun.com/ultra1nvram.html

Or at least as an interesting detail on the eeprom chip 

Bill Schwanitz

If A is a success in life, then A equals x plus y plus z. Work is x; y is play; and z is keeping your mouth shut. - Albert Einstein.

> On Apr 3, 2015, at 2:36 PM, Ethan Dicks <ethan.dicks at gmail.com> wrote:
> 
>> On Fri, Apr 3, 2015 at 2:29 PM,  <jep200404 at columbus.rr.com> wrote:
>> I had forgotten about those. Was it actaully battery backed up
>> RAM? If I recall correctly, at least some had a conventional
>> low power static RAM chip, maybe with some clock stuff, and a
>> battery potted in epoxy to look like a tall 24 or 28 pin DIP chip.
>> I might be confusing your EEPROM thing for what I messed with.
> 
> Old SPARCs absolutely used SRAM+clock circuit and an embedded Li
> battery.  I'm not sure if they changed with the Ultra line or not.
> 
>> If one is desparate enough, one can use a Dremel to grind through
>> the epoxy to the lead frame connections to the battery to
>> disconnect the old battery and connect a new battery
>> (with a socket!!!). I think there was some trick for loading
>> data into it by plugging into a live socket in a running PC.
> 
> I've done that.  I have a couple examples of what works - there are
> pictures on the Internet for the process.
> 
> Here's a deep-cut job - they took the backpack off and ran wires for
> an external battery and left the clock crystal hanging over the SRAM
> DIP...
> 
> http://www.kk.iij4u.or.jp/~taokamur/luna68k/img/NVRAM5.jpg
> 
> -ethan
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