Page 1 of 1

Two-IC hotswapping device. Where is it?

Posted: Thu Jan 06, 2005 12:36 am
by Elorg
Hello,

I was wondering if any of you remembers the website detailing one ingenious constraption for BIOS hotswapping. You'd plug both EEPROMs in your homebrew PCB, and then the PCB into your mainboard where the original BIOS chip used to sit. Then, by operating a switch, you'd select from which chip does the system read or write to.
Perfect for smooth hotswapping (no risk of shorting out the leads while attempting to pry the chip out of its socket!) and absolutely the best thing around for experimenters like me.

As far as I recall, the only thing it did was cutting the power from one chip at a time, but I'm not sure anymore.

-Is the website with schematics for this thing still operational?


Another thing; I assume that ordinary EPROMs can't be reprogrammed in PC mainboards, even after clearing them out with ultraviolet light?

Posted: Thu Jan 06, 2005 3:41 am
by ajzchips
I've seen people buy small ZIF adapters; makes hotswapping simple too.

You need more than 12V to program standard EPROMS.

Posted: Thu Jan 06, 2005 2:36 pm
by sulbert
Was it a Russian site?
I have a PDF schematic of that thing on my CD-R-s somewhere (will look for it).
CE signal was used to enable/disable either chip. I've see one device that didn't have a PCB at all, just a bunch of wires, a switch, and the sockets.

Posted: Fri Jan 07, 2005 3:14 am
by Elorg
Sulbert, thanks for your input!

Honestly, I can't remember if it was a russian website - it's been two years since I last saw the device and my memory fails me.

However, I would really appreciate if you could find the schematic on your cds - I'm not in the mood for experimenting with this as I'm rather short on spare EEPROMs! :(

Posted: Mon Jan 10, 2005 10:34 am
by sulbert

Posted: Tue Jan 11, 2005 3:47 am
by Elorg
sulbert wrote:Found the schematic.
Thanks a lot! I'll build it shortly - good think that I'm handy with soldering iron. And russian language. :wink: