On Sun, Dec 18, 2011 at 3:09 AM, jb-electronics <[email protected]> wrote:
> do you really have four PWM channels? I only see three in your schematic. Yep, 4 independent PWM channels. There are currently two minor flaws in the design I plan on fixing: 1) The one challenge I ran into using these 4 channels and attempting to keep Arduino compatibility is that the tone output libraries use the same timer as used by one of the channels. So, in order to sound the alarm/speaker, I have to disable the PWM whenever it's sounding. 2) The buzzer I use is a magnetic transducer. There's danger of back EMF, but I don't have a protection diode, so I plan on adding one. Also, it's currently overdrawing current on the Atmega pin whenever it's used. I fixed this in my current batch by splicing in a resistor (resulting in a loss of a few dB). But I'll drive it through a transistor in the final design. Sean -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
