Audio Level Meter

[savnik]

and build log scale.

How i build log scale.
I use linear scale now.

[malc-c]

You need to use the line in level (normally 1v peak to peak RMS) from a CD / Tape deck. You then need to make a filter fo that the peaks provide a cleaner input (well at least thats what I used form my disco light project).

The attached image shows the filter I used to input the signal into an 877 PIC. I can't post the code as it was written in JAL (before I discovered PBP ) but works on the pinciple of converting the voltage to a value between 0 and 254, and then making pin on the output port go high, so for example, if the input equated to 120 the first four pins RB0 - RB3 would be made high. Its not quite a true VU or Peak level meter, and I'm sure with re-coding you could do something better, but the effect to a decent track with lots of quiet bits between the beat looks cool

[Excelcier]

The reason I'm doing this on a PIC and not a LM3914, LM3915 OR LM3916 is because I wrote software for LED light patterns and I simply want to use the music input to trigger the stages of the patterns I programmed.

[savnik]

The attached image shows the filter I used to input the signal into an 877 PIC. I can't post the code as it was written in JAL

If you want post the code or send to email.
I know JAL.

[malc-c]

I don't know if I still have it... I'll have a look on my archive to see if I can find it