Run time timer

Started by nuepatrick July 26, 2006
I have a project that I am designing and I need a simple accurate
timer that starts when power is applied to the circuit. I need to
display this on a bpi-216.

Any ideas would be appericated.

Thanks

Patrick
Determining elapsed time from start of the current execution is
trivial, Patrick; that's the value currently in the RTC, which starts
at midnight every time you apply power. Your problem is how to store
an accumulation of that time without missing much (you don't have the
luxury of a "powering-down" interrrupt that might allow to to save the
time just before losing control) - and you must avoid burning up
EEPROM, which usually means you must distribute the accumulating value
you want to store over several or many changing EEPROM locations.

This has been discussed; search for "Persistant" and "Hobbs", and
you'll can find Atmel's PDF on the matter in the file section.
Tom

Hi Patrick,

I would use a BX-24. It has the timing and RTC resources, serial interface for the LCD, and is easily programmed for this kind of task.

Best Regards, Eric

----- Original Message -----
From: nuepatrick
To: b...
Sent: Wednesday, July 26, 2006 6:32 AM
Subject: [BasicX] Run time timer
I have a project that I am designing and I need a simple accurate
timer that starts when power is applied to the circuit. I need to
display this on a bpi-216.

Any ideas would be appericated.

Thanks

Patrick