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The only thing worse than these soldered-in batteries are those motherboards with the Dallas DS1287 RTC “brick” ICs. They had a coin cell buried inside the chip

The only thing worse than these soldered-in batteries are those motherboards with the Dallas DS1287 RTC “brick” ICs. They had a coin cell buried inside the chip[1] with no way to provide external power should it drain. [1]: http://www.mcamafia.de/mcapage0/dsrework.htm http://www.mcamafia.de/mcapage0/dsrework.htm

alnwlsn 2y ago
The only thing worse than that is when those things are soldered and not in a DIP socket. They still make them (or a compatible version) by the way, sealed battery and all.
TeamMCS 2y ago
Ah yes. I've had to repair one of the Dallas ICs before. You have to dig out a dremel and bite down till you get to the metal then add some hook up wire. Unlike OP I chose to use rechargable batteries that used to be used for home wireless phones - they are the right voltage and often they supply a battery charger. If you're lucky you can desolder the the old battery and use a couple of pin headers to get you back up and running. I do find it irritating some retro machines wont even boot without a working battery.
adrianmonk 2y ago
Yeah, those are a thing on old Sun workstations. They have a clock and they also store a small amount of data. https://www.sun3arc.org/FAQ/sun-nvram-hostid.faq.phtml https://www.sun3arc.org/FAQ/sun-nvram-hostid.faq.phtml I remember replacing one in the mid 1990s. The machine's ethernet address is stored on this chip, and I believe it's battery-backed RAM (not flash, EEPROM, etc.), so when the battery dies, the data on the chip is lost. When you install a new chip, you need to program in the ethernet address so the machine can get on the network. The proper thing to do is use the factory-assigned ethernet address to ensure that it is unique. But you can't get the address from the old chip. So, like many people, I just picked some random numbers. It worked.
rzzzt 2y ago
Necroware has a replacement design for Dallas RTCs: https://github.com/necroware/nwX287 https://github.com/necroware/nwX287
- hyhconito 2y ago
  I don't know why there is a replacement design. You can still buy them new from Mouser. They last 20 odd years usually.
moffkalast 2y ago
Is this some attempt to get around "contains batteries" shipping restrictions, since if anyone looks inside it'll just be like any other chip and there's no way to tell unless you start googling part serials lmao. "No batteries here, officer! Move along."
Bluecobra 2y ago
I'm not sure if it's worse, since AFAIK these don't leak. I have a IBM PS/2 system that I inherited that I plan to restore some day. Sure it's a pain but glad there was no damage to the board.
deleted 2y ago
[deleted]
blueflow 2y ago
Dedication and a cutter knife do it. I did it myself, twice. Once while it was soldered into a mainboard :P
userbinator 2y ago
There were lots of test equipment with variants of those, and unlike CMOS settings, they held critical calibration constants.
rasz 2y ago
>no way you drill/dremel in two spots, solder tow wires and you are done. https://www.classic-computers.org.nz/blog/2009-10-10-renovating-a-dallas-battery-chip.htm https://www.classic-computers.org.nz/blog/2009-10-10-renovat...
- geon 2y ago
  You can also heat them up, making the resin brittle so you can chip it away and replace the battery.

alnwlsn 2y ago

The only thing worse than that is when those things are soldered and not in a DIP socket. They still make them (or a compatible version) by the way, sealed battery and all.

TeamMCS 2y ago

Ah yes. I've had to repair one of the Dallas ICs before. You have to dig out a dremel and bite down till you get to the metal then add some hook up wire. Unlike OP I chose to use rechargable batteries that used to be used for home wireless phones - they are the right voltage and often they supply a battery charger. If you're lucky you can desolder the the old battery and use a couple of pin headers to get you back up and running. I do find it irritating some retro machines wont even boot without a working battery.

adrianmonk 2y ago

Yeah, those are a thing on old Sun workstations. They have a clock and they also store a small amount of data. https://www.sun3arc.org/FAQ/sun-nvram-hostid.faq.phtml https://www.sun3arc.org/FAQ/sun-nvram-hostid.faq.phtml I remember replacing one in the mid 1990s. The machine's ethernet address is stored on this chip, and I believe it's battery-backed RAM (not flash, EEPROM, etc.), so when the battery dies, the data on the chip is lost. When you install a new chip, you need to program in the ethernet address so the machine can get on the network. The proper thing to do is use the factory-assigned ethernet address to ensure that it is unique. But you can't get the address from the old chip. So, like many people, I just picked some random numbers. It worked.

rzzzt 2y ago

Necroware has a replacement design for Dallas RTCs: https://github.com/necroware/nwX287 https://github.com/necroware/nwX287

hyhconito 2y ago
I don't know why there is a replacement design. You can still buy them new from Mouser. They last 20 odd years usually.

moffkalast 2y ago

Is this some attempt to get around "contains batteries" shipping restrictions, since if anyone looks inside it'll just be like any other chip and there's no way to tell unless you start googling part serials lmao. "No batteries here, officer! Move along."

Bluecobra 2y ago

I'm not sure if it's worse, since AFAIK these don't leak. I have a IBM PS/2 system that I inherited that I plan to restore some day. Sure it's a pain but glad there was no damage to the board.

deleted 2y ago

[deleted]

blueflow 2y ago

Dedication and a cutter knife do it. I did it myself, twice. Once while it was soldered into a mainboard :P

userbinator 2y ago

There were lots of test equipment with variants of those, and unlike CMOS settings, they held critical calibration constants.

rasz 2y ago

>no way you drill/dremel in two spots, solder tow wires and you are done. https://www.classic-computers.org.nz/blog/2009-10-10-renovating-a-dallas-battery-chip.htm https://www.classic-computers.org.nz/blog/2009-10-10-renovat...

geon 2y ago
You can also heat them up, making the resin brittle so you can chip it away and replace the battery.