EEPROM Problem

[Trax (Gast)]

I work with a at90s2313 at 3V. I'have some problem to read the memory
eeprom when i switch on my microcontroller. It seems it forgets all
when i switch off the microcontroller, but it doesn't forget if i will
push reset.I'm programming in C, and i don't use the standart
library, i used the explication on Atmel's datasheet. which can be the
cause?

[Hannes Lux (Gast)]

It's normal, work at voltage >4 Volts...

(sorry for my bad english)

Also das ist normal, hatte ich auch, aber mit dem AT90S1200 und dem
AT90S8515. Die S-Typen funktionieren erst ab 4V zuverlässig. Der 1200
löschte nicht das EEPROM, sondern brannte bei zu geringer
Versorgungsspannung absoluten Blödsinn hinein...

Für kleinere Spannungen sollte man schon die LS-Typen nehmen...

...Bit- & Bytebruch... - ...HanneS...

[Peter D. (peda)]

On older AVRs an external reset circuit (e.g. MAX690) must be used, on
newer AVRs the brown out fuse must be enabled.
Otherwise the EEPROM may be corrupted during power off / on.


Peter

[trax (Gast)]

what's the brown out fuse? How enable it?

[Peter D. (peda)]

"what's the brown out fuse? How enable it?"

Only present on newer AVRs e.g. ATTiny2313.


Peter