I have an old Emerson 500EC that I am trying to resurrect. This is a 80286-16 MHz machine with 30 pin simms, I have 4 megs of memory in it. During boot up, it tells me that the CMOS battery is low, and I believe it, based on it's age and it has been in storage for years. My problem is, I have not been able to locate a CMOS battery, I don't see any of the usual cells, be it a 2032 coin cell, or a lithium battery that plugs into the main board.
Searching on the web for a company that claims to have made this computer has not been fruitful. The Emerson company based in St Louis doesn't seem to know anythiung about it.
There is a Dallas semiconductor clock on board, I believe it has a battery in it that has gone dead, but I find it unusual that it is also the battery for the CMOS memory, I could be wrong.
I anybody has any experience with these machines, and can offer me some advice, I would sure appreciate it.
I'm fairly certain that that Dallas semiconductor clock package is a black rectangle, right? Well, the battery is unfortunately sealed inside -- in a block of epoxy.
It is possible to buy replacements for that clock/battery package, but unfortunately they are all new old stock, which means the batteries sealed inside them were made years, if not a decade, ago, and they are mostly bad by now.
In a Sun machine that had one of those clocks, I had success in hacking away at the plastic to expose the battery and then wiring up an external 3V battery to the clock package, but that operation can get a little tricky. Short of that or finding a replacement Dallas component, you're out of luck.
Let us know what happens, and good luck!