[Elecraft] [KPA500] Rear power switch thread

[Don Wilhelm]

Are we going "full circle"?  Battery backed RAM was the "thing" when the 
IBM PC was announced (way back when), and then as technology progressed, 
that changed to EEPROM which did not require voltage to retain the 
settings.  I hope we are not going back to that voltage dependent 
situation for the K3.  As I recall from the IBM computer example, if the 
data was something different than the currently displayed frequency, it 
might be lost with the power outage example.

73,
Don W3FPR

On 12/1/2011 3:59 PM, Wayne Burdick wrote:
> The K3 (like the K2 and our other rigs) uses EEPROM for nonvolatile
> parameter storage. This decision was based on several criteria, and we
> believe it was the right choice at the time. It's conceivable that in
> a future product we might go with battery-backed-up RAM.
>
> The MCU does try to write all changed parameters to EEPROM in the
> event of power disappearing suddenly; the electrolytic capacitors do
> hold up the MCU's voltage for some milliseconds. But your humble
> firmware guy is a lot happier when power is turned off at the radio
> first, allowing a clean shut-down sequence.
>
> Thanks for your tolerance of our various idiosyncrasies.
>
> 73,
> Wayne
> N6KR
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Elecraft at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>