Sun Ultra 5 - Dead NVRAM Battery Fix

Mike

New Member
I took a break from my usual Commodore shenanigans this weekend, and fixed up a Sun Ultra 5 I've had sitting around for a while.

IMG_20190803_153219262_HDR.jpg

These machines have a common issue as they get older, in that they have a battery-backed memory store for things like time, date - and not very helpfully - the ethernet MAC address. To add insult to this situation, the battery is attached to the memory chip with a solid blob of polymer. They took design lessons from the C64 PSU manufacturers, obviously.

Here's our little monster.

IMG_20190803_154500860_HDR.jpg

The main obvious symptom of this issue is the message "The IDPROM contents are invalid." on boot, and the MAC address displayed as ff:ff:ff:ff:ff:ff - and while you can easily reset the address from the firmware, it's going to be lost every time you power off the machine.

The entire thing is replaceable, you can find places that'll ship you a new one - but that just pushes the problem off for later. It'll happen again. What's better is adding a connector for a battery that you can easily change later. A CR2032 cell works great. I had a suitable holder, and a bit of time, so I thought I'd get things done right.

With the help of some great photos and diagrams of the NVRAM battery placement it wasn't hard to get into the right spot with a Dremel and expose some contacts. I stuck the chip legs into a tiny breadboard I had to keep them straight and protected during this process.

IMG_20190803_163639092_HDR.jpg

Once that was done, it was easy enough to solder a couple of wires into place, and connect up the CR2032. I just used some really strong double-sided tape to mount the battery holder. I think I'm going to revisit this at some point and completely remove the old battery, as it may eventually leak and cause some serious problems that won't be so easily correctable.

IMG_20190803_173652299_HDR.jpg

IMG_20190803_182446642_HDR.jpg

Once that was done, it wasn't much work to get a quick OpenBSD install up and running to verify everything was working great, and a spare PCI USB card I had in a drawer from my old Blue & White G3 Mac turned out to work perfectly in there as well, so I can now just use USB sticks to transfer files to it, and to give me a bit more space in a pinch as the HDD in there is only 9GB.

IMG_20190804_010630800_HDR.jpg

I'll be writing this up properly on my blog at some point, but that'll happen when I do the rest - it still needs a lot of cleaning (as that last photo probably shows), I might even retrobrite the front of the case, and I'm going to get an extra Compact Flash/IDE adaptor and replace the HDD with maybe a 16GB flash drive. Just thought it might be interesting to share one of the less common little fixes for older hardware.
 

TheGeekPub

The Geek Pub
Staff member
May 15, 2019
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Keller, TX
www.thegeekpub.com
I took a break from my usual Commodore shenanigans this weekend, and fixed up a Sun Ultra 5 I've had sitting around for a while.

View attachment 169

These machines have a common issue as they get older, in that they have a battery-backed memory store for things like time, date - and not very helpfully - the ethernet MAC address. To add insult to this situation, the battery is attached to the memory chip with a solid blob of polymer. They took design lessons from the C64 PSU manufacturers, obviously.

Here's our little monster.

View attachment 170

The main obvious symptom of this issue is the message "The IDPROM contents are invalid." on boot, and the MAC address displayed as ff:ff:ff:ff:ff:ff - and while you can easily reset the address from the firmware, it's going to be lost every time you power off the machine.

The entire thing is replaceable, you can find places that'll ship you a new one - but that just pushes the problem off for later. It'll happen again. What's better is adding a connector for a battery that you can easily change later. A CR2032 cell works great. I had a suitable holder, and a bit of time, so I thought I'd get things done right.

With the help of some great photos and diagrams of the NVRAM battery placement it wasn't hard to get into the right spot with a Dremel and expose some contacts. I stuck the chip legs into a tiny breadboard I had to keep them straight and protected during this process.

View attachment 171

Once that was done, it was easy enough to solder a couple of wires into place, and connect up the CR2032. I just used some really strong double-sided tape to mount the battery holder. I think I'm going to revisit this at some point and completely remove the old battery, as it may eventually leak and cause some serious problems that won't be so easily correctable.

View attachment 172

View attachment 173

Once that was done, it wasn't much work to get a quick OpenBSD install up and running to verify everything was working great, and a spare PCI USB card I had in a drawer from my old Blue & White G3 Mac turned out to work perfectly in there as well, so I can now just use USB sticks to transfer files to it, and to give me a bit more space in a pinch as the HDD in there is only 9GB.

View attachment 174

I'll be writing this up properly on my blog at some point, but that'll happen when I do the rest - it still needs a lot of cleaning (as that last photo probably shows), I might even retrobrite the front of the case, and I'm going to get an extra Compact Flash/IDE adaptor and replace the HDD with maybe a 16GB flash drive. Just thought it might be interesting to share one of the less common little fixes for older hardware.

This is fantastic!
 
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