MiDI IO 128 : Pots setup

[chapelier fou]

Hi !

I want to connect 8 pots to my Midi I/O core.

When i edit a preset file within a table editor, it displays inputs 0 to 5. I would imagine it going from 0 to 7. Can i simply add 2 lines in the table ?

thanks !

[chapelier fou]

As a side note, i've got a lot of parasites when sending a CC. My Pots are 4.7 KOhm with 100 nF capacitors. it looks like the capacitors are not filtering anything.

By parasites i mean many occasional drops to 127, or constant flow of +/- 1 in the CC's value.

Any idea ?

[TK.]

Hi,

 

J5B.A6 and J5B.A7 are allocated by the third MIDI IN/OUT port, therefore these pins can't be used as analog inputs.

 

And the "parasites" (jittering values) are unfortunately normal - there is no way to fix this properly. The LPC17 has bad ADCs, and they are only working at 3.3V which means that the s/n ratio is lower than for ADC working at 5V.

Therefore the usage of the AINSER64 module is recommended.

 

In future, also an inexpensive AINSER8 module for 8 inputs will be available: http://www.ucapps.de/mbhp/mbhp_ainser8.pdf (prototypes are ordered).

Due to the simplicity, this "module" could also be built on veroboard (cheapest solution).

 

Best Regards, Thorsten.

[chapelier fou]

i see ! Makes sense !

Well, i'll go for an AINSER 64 then !

Thank you very much for your answer. MidiBox is so great... awesome community as well.

[folly]

HI

Solved the problem of parasites with Ainser64?

thank!

[chapelier fou]

Hi folly !

i'm still waiting for my AINSER64 kit, it should arrive shortly. I'll let you know, but i'm pretty confident, since TK. recommended it precisely for this reason.

I'll post back here.

[folly]

I have not yet solved the problems with jitter even though I tried with ainser64. 

 

with STM32F DISCOVERY you solve this problem?

[chapelier fou]

Very sorry, i've used midibox only once, and since i broke my AINSER chip, i ended up using an arduino for pots.

[folly]

HI!  that the project ARDUINO used?