Music Input

[malc-c]

Thanks for the reply,

Sounds good (sorry no pun intended), I'll have a play and see what I can do.

Cheers

[Melanie]

If and when you get ADCIN to work with a 16F628A, come back and tell us how you did it. That PIC hasn't got any ADC's...

[malc-c]

Sorry I dow to your superior knowledge.. so what's an analogue comparator input then.. will it not do the same thing... ??

[Acetronics2]

Hi, Malc

Some years ago, Elektor committed such a project with a 16F84 ... you could have a look to their input stage ...

16F628 is a "bigger" '84 ...no ???

Alain

PS : Project 000107 ... note everything Downloadable ...

[malc-c]

Thanks for that, but me been a tight ass brit object to having to pay a quid to obtain access to the article... especially when the HEX and ASM are free !!

I did come accross this project, which appears to use the filtered bass to trigger an NE555 to provide the logic pulse to trigger another NE555 which can run as an astable free runner or mono-stable triggered by the music.






The actual chase generator is a 4017 decade counter. ( full project details http://sound.westhost.com/project62b.htm )

I might just try this, however it seems a but of an overkill to use all those op-amps and an NE555 to provide the input into a PIC.... I'll keep googling and yahooing and see what turns up

[Melanie]

An Analogue Comparator allows you to trip your input pin at different voltage levels determined by an internal or external reference. So, if you set your Reference voltage at say 500mV, you can trip the Comparators Output on or off at 500mV rather than the usual trip level for a Digital I/O pin.

By sweeping the Comparators Reference Voltage, you can then use its input as a cheapo ADC. However, the internal Reference in the 16F628 only has two scales of 16 steps, and allowing for a settling time would not be very good for Audio input sampling.

So, in reply to your query, an Analogue COMPARATOR does what it says... it COMPARES your input against a Reference. Whilst an Analogue to Digital CONVERTOR (ADC) will give you a snap-shot of your current Analogue input in Digital form. The two are NOT the same.

The 16F628 has TWO COMPARATORS on-board and NO ADC's. ADCIN only functions with ADC's which is why it's named ADCIN (that what I love about microprocessors, they name everything so obviously!).

[Acetronics2]

but me been a tight ass brit object to having to pay a quid to obtain access to the article... especially when the HEX and ASM are free !!

Let's see how much you hope to save ( let's do the whole count for the project ) ... makes me laugh !!!

mmmh, by the way ... have a look to Freescale MC 3340 P datasheet. An old Elektor ( once more, ... !!! ) summer issue show a really nice application

You'll be more than happy : datasheet is free ...

you fast draw, mmmmh ???

Alain

PS : 5or 8 £ for a pre-programmed basic PIC ( 675,628,84 ...) ... you're joking, I hope !!!

[malc-c]

Melanie,

Thanks for the explanation. I understand where my confusion came from now !

[malc-c]

Ok I've looked at the PDF (http://www.ee.washington.edu/stores/...ear/mc3340.pdf) for that device, but how does an electronic volume control fit in with my bass extraction / filter thingy ???

PS : 5or 8 £ for a pre-programmed basic PIC ( 675,628,84 ...) ... you're joking, I hope !!!

Whoops - thanks for pointing out the typo... should be £5 like the rest.. now corrected.

And before you ask, that just covers the cost of the PIC and postage to me, then the cost of the post, packing and paypal charges when sending it out again !