Why does my Core make random data?

[Guest epochsounds]

My Core emits random midi data.  The LCD displays numbers rapidly changing and my computer's MIDI monitor scrolls garbled CC changes.  This happens with all the applications I've tried.  With the MIDIbox 64 application from the download sections it transmits this useless data very rapidly, and with the ain example it creates random changes occasionally.

[moebius]

Hi,

This sounds very much A/D pins floating..

So you have AINs connected (that's good)?  Any unused inputs on AINs should be tied to ground.

Bye, Moebius

/edit: Hmm.. Too tired to separate AINs /AOUTs.. ;) Fixed.

[Guest epochsounds]

Thanks Moebis.  Actually I'm in the process of throwing together my AIN so all my tests on the core have been with a core and nothing else.  

What are the A/D pins?  

I don't have an AOUT module.  Do I have to do anything to the core with regard to AOUT?

Thanks again!

[moebius]

Ok,

If you don't have AINs connected to core, it's perfectly normal (and it indicates that you a core running, probably with MidiBox64 firmware ;)) to get random midi event.

It's because A/D converter in PIC to which AINs connect tries to sample voltage, and it's not connected - floating pins -  which in turn means random fluctuations: Random midi events.

Same can happen if you don't connect pots to you're AIN board, and fail to "terminate" or tie unused inputs to ground level.

Bye, Moebius

So, Sorry. Nothing to do with AOUT..

[goyousalukis]

If you load an application like the mb64e that doesn't use the AIN module, you shouldn't get any random midi-events. That might be a starting point. Another option is to connect pins A0 - A7 of J5(on the core) to ground. This will guarantee that there is no jitter from open pins.

Justin

[Guest epochsounds]

Valuable information.