Possibility for Digital controlled pots

[msi]

I know that there are digital controlled pots available and that those pots could be controlled using a Sid modual and the serial protocol.  Unfortunatly I believe currently only one sid modual is possible for every core modual.  I have been looking online and have found a method of a digitally controlled pot using ditigal switch's and LDR's.  

Would it be possible to utilize something like this with the current midibox design for controlling multiple LDR pot's?  The goal would be to automate something like rack effects via midi, or even an amplifier or mixing consol.

William

[TK.]

Hi William,

I know that there are digital controlled pots available and that those pots could be controlled using a Sid modual and the serial protocol.  Unfortunatly I believe currently only one sid modual is possible for every core modual.

search for digital pots with 3-wire interface (SPI), example:

http://www.maxim-ic.com/DigitalPotentiometers.cfm

they can be daisychained like it has been done for the DIN and DOUT modules. So in fact only latency requirements limit the number of addressable devices per chain.

The aout_example_v1_4.zip under MIOS->Download demonstrates, how to control multiple devices via SPI

I have been looking online and have found a method of a digitally controlled pot using ditigal switch's and LDR's.

this circuit will kill you, once more than 4 bit resolution is required ;-)

Best Regards, Thorsten.