a classiccmp electronics project?

[Rob O'Donnell]

At 14:29 30/07/2004, Jay West wrote:

> > Secondly, you need to halt the device while the SRAM is loaded.
>I would envision the SRAM load to only happen once, during power up. One
>could build in a reset button and dip bank switch or micro rotary switch
>that would make it load different contents, but it would be up to the
>operator not to do that while the system was running.


Just my idle thought, reading through this thread, but would it be possible 
to provide some sort of battery backup (maybe rechargeable?) for the SRAM 
on this device?  Then you don't have to worry about copying out of EPROM 
(or whatever) into the SRAM in those few ns as you power up the machine, as 
it's already in there from last time?  Have a hefty enough battery to run 
the PIC/whatever, and you can even select the ROM image and re-load the 
SRAM while the rest of the system is still powered off.

Rob