Do you have the brownout reset enabled? What voltage? If the supply is below the BOD the processor will never come out of reset.
-----Original Message----- Hi Bob, I may not have time to draw and post a diagram before heading to the airport for my meeting tomorrow, but verbally here it is: AVR:GND to ground end of 3 AAA's in series AVR:Vcc to +4.5 end of 3 AAA's 1uF bypass capacitor PA0-PA7 to input pins on 7-segment display each (of 2) 7-seg ground pins through 100 Ohm resistor to ground (Yes, it's common cathode.) That's it. I have not got this working yet, but the circuit still works correctly when powered by the STK500, so I am now wondering whether the problem is the need for an external clock, as Michai suggests. However, I have switched to an alternate strategy, and I am now stringing 9 AA batteries together to power the STK500. This is working, so far. Any guesses how long these batteries can power this setup? I only need about an hour... -Marge On Tue, 11 Mar 2008, Robert L Cochran wrote: > Can you post a circuit diagram? Have you worked out a power budget for > the circuit? I'm following the discussion with great interest. > > Thanks > > Bob Cochran > > > > Marge Coahran wrote: >> Does anyone have experience running AVRs on batter power? I want to >> give a brief demo at a venue without AC. I was hoping that 3 AAA >> batteries would work, since that gives 4.5V and the datasheet says the >> AVR I am using (Atmega8515L) can accept 2.7-5.5V power supply. >> However, this does not work. Perhaps AAA does not produce enough >> current? Does anyone know if using larger batteries (AA, C, etc) would >> work, and if so what batteries I need? >> >> Marge >> >> >> _______________________________________________ >> AVR-chat mailing list >> AVR-chat@nongnu.org >> http://lists.nongnu.org/mailman/listinfo/avr-chat >> >> > _______________________________________________ AVR-chat mailing list AVR-chat@nongnu.org http://lists.nongnu.org/mailman/listinfo/avr-chat _______________________________________________ AVR-chat mailing list AVR-chat@nongnu.org http://lists.nongnu.org/mailman/listinfo/avr-chat
