[sdiy] Tap Tempo LFO/Clock

[Tom Wiltshire]

Hi All,

I'm currently working on a new version of my PIC voltage-controlled  
LFO code. I've added a "tap tempo" feature. This measures the time  
between two rising edges on one input pin and sets the LFO frequency  
based on the result. It'll work with a momentary push button or a  
0-5V pulse train, so it works as a sync-able LFO too.
I've also got a 0-5V pulse output which is intended for clocking  
sequencers and such like, so you can have a tap tempo clock for a  
sequencer.

Currently the chip has much the same features as the VCLFO that I  
started from (http://www.electricdruid.com/index.php? 
page=projects.lfo9) but I'm thinking that it probably doesn't need  
the S&H as a separate module. Instead I might replace one of the  
other waveforms with a RND wave, like the SH101 does.

I've got a few questions:

What applications do you see for a chip like this?
What features would you like to see on a chip like this?
What could I get rid of from the original VCLFO?

Finally, a few people have written to me in the past asking if my PIC  
LFO could be used for guitar effects pedals. With a tap tempo  
feature, it definitely could, so I'd like to promote the project on  
the relevant forums, but I don't know which they are. If anyone knows  
any good DIY guitar effects forums where you think people would be  
interested in this, could you let me know?

Thanks,
Tom

PS: I'm also looking at the 16F688 as a MIDI-to-clock-pulse convertor  
chip, and perhaps in the other direction too. There was a  
conversation about such a thing recently, and no-one seemed very  
impressed with the Doepfer solution.