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Tap tempo diy

Started by Galego, August 12, 2010, 07:15:29 PM

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Galego

Well, it seems i'm a bit stubborn in wanting to do everything myself, even if there are already made and available solutions like the PTAP...

Just finished my first version of a tap tempo on the breadboard, using a PIC 16F684. It's just a simple tap tempo, i don't want multipliers and other fancy stuff. Just enough so i can tap the tempo with my foot and that's it.
http://www.youtube.com/watch?v=qrx1sCFXhNs

First i was thinking of using a vactrol to control the delay time, but i doubt it will have the precision needed for accurate timing. Now i've seen people use the MCP41050 digital potentiometer, which shouldn't be too hard to use, but i don't know if i can find them locally.
Does anyone know where i can order them from in Europe?

Any other suggestions?

Hides-His-Eyes

Digital pots should be easy to find on fleabay, there are some for sale from HK I think.

How long did it take you to be able to code something like this? I know C++ and Basic but not the assembly code these use. I have an idea I want to be able to do with PICs but don't really know where to start!

Galego

I started by looking into the TAP Tempo LFO by electricdruid. I learned a lot there, and my initial thought was to hack his code into doing what i wanted.
But i was having a lot of trouble getting through the ASM code, i spent a few days learning the architecture of the PIC i was using working and doing basic programs. Then i finally came to the conclusion it would be too long to be able to do anything practical with it. I just don't have the time to dedicate to it. So i gave up and went looking for basic compilers.
So, i used a basic compiler that i erm hum... well, downloaded :D
With basic it was a breeze. I was just left with making sure the code worked and that i was using the right ports and setting the right bits in the configuration.

There's a lot of information around the web, you just need to be patient and let it sink in. I also found it very useful to get an LCD display. I used it as a debugger as i was learning, to let me know the values of variables.

Do you have a link to those digital pots on ebay? I couldn't find any.



Galego

Thanks, i ended up ordering directly from microchip.