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Software => Software => Topic started by: HDL_CinC_Dragon on July 30, 2007, 07:23:36 AM

Title: Send out specific frequency from AT Mega 8
Post by: HDL_CinC_Dragon on July 30, 2007, 07:23:36 AM

Is there a way that I can program my AT Mega 8 to output a specific frequency, lets say 6kHz(6000Hz) just for an example, to any one of the B, C, D pins?

Title: Re: Send out specific frequency from AT Mega 8
Post by: hazzer123 on July 30, 2007, 08:45:57 AM

Maybe you could use one of the timers to interrupt every 1/6000th of a second. This would let you get on with other things at the same time. Maybe there are other ways you could do it using hardware, but i don't know much about ATMega chips.

Title: Re: Send out specific frequency from AT Mega 8
Post by: Robotboy86 on July 31, 2007, 05:25:50 PM

Does it have a sound command?  Those are usually good for sending out a frequency.  Or you could get a voltage -> frequency ic..

Title: Re: Send out specific frequency from AT Mega 8
Post by: HDL_CinC_Dragon on July 31, 2007, 07:41:29 PM

I want to be able to hook up a piezo disc to the pin and have it play at what ever frequency is running out of that pin.

Title: Re: Send out specific frequency from AT Mega 8
Post by: Admin on August 02, 2007, 11:58:46 AM

Since you dont care about any particular frequency, use the exact same code that I use for servos on my $50 Robot. Then just change the frequency until you hear a sound.

If you want a perfect frequency, hook up the output pin to an oscope.

Title: Re: Send out specific frequency from AT Mega 8
Post by: HDL_CinC_Dragon on August 02, 2007, 01:38:25 PM

Well since I dont have an OScope and theyre expensive that option is out lol but I can get hold of one for a bit when the school year starts up again (:'()

Right now I cant experiment with anything like that at the moment because I need to buy a battery charger so I can use my battery again since the USB cable doesnt put out nearly enough amperage (about .4A)

Thanks for your help Admin

Title: Re: Send out specific frequency from AT Mega 8
Post by: Admin on August 02, 2007, 03:42:31 PM

Cant find any power supplies around to charge your batteries?

Title: Re: Send out specific frequency from AT Mega 8
Post by: HDL_CinC_Dragon on August 02, 2007, 05:45:01 PM

Well I could probably make one... But I think it would be best if I just bought a smart one (http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=1566) so I dont risk killing my battery...