AVR-Chat

Hello!

I'm JJ, AVR, electronics, machinist type person. It's good to find a 
resource for AVR folks.

I have two designs that use an AVR. One is a garage door manager, using 
a 2313, keypad, dip relay driven by a transistor. On occasion it would 
just "go nuts." The door would start going up-down-up-down at about the 
speed you read that.

The other is a heater controller. It uses an 8535 to read an LM74(37?) 
temperature device, and turn a space heater on and off. It uses a hiigh 
current mechanical relay driven by a transistor that is driven by an 
optoisolator (4N22?). It has the same problem as the garage door 
control. Sometimes, it gets spastic, turning the relay 
on-off-on-bzzt-off-bzzt, etc.

I use the normal resistor to Vcc, cap to Gnd on the reset line, along 
with bypass caps (100nf) close to the ICs. I guess I'm missing 
something. Any suggestions? I really like the AVR, and am trying to 
convince myself it something I've done, so I won't think they're 
unreliable.

Thanks!

Regards,
   JJ