I've got a mini-game coded with an ATTiny84, a shifter, 7 LEDs and two buttons, plus accompanying resistors. It works great! Until I connect a passive piezo buzzer, that is. Then the timings go off, code gets "stuck", it's really strange.
The amazing thing is I don't even need to USE the buzzer -- just having it in the circuit kills the system. The moment I unplug it from ground everything works.
I'm powering the whole thing up with 3 AAAs as per recommendations elsewhere. No voltage regulators or capacitors... could that be the problem? Or is it an ATTiny84 thing? Anyone know what's going on?
(I had the buzzer working fine before when I was using an ATMega128 and the Arduino UNO's power source.)
Am I missing something like this? Using a microcomputer in the drive circuit of a piezo buzzer
Thanks in advance!