Input from a slide switch into the ADAU1701 DSP?

Dave's suggestion of alternating "hot" and "ground" wires in a ribbon cable is an excellent one. Twisted pairs may also work in a pinch. The 33 ohm resistor you see on the DAC board is a damping resistor. It suppresses the ringing often found in these signals. Have a look with your oscilloscope at the receiving end of your I2S signals between the boards. If you observe ringing, add more resistance at the source end of each affected signal. Effective values often range from 22-100 ohms. For an example of this effect, please see:

Damping Resistor(s) for MCLK Distribution

Best regards,

Bob

Sorry Bob,

I branched this post from the other thread because it was not about the topic of the thread. It looks like you answered this post rather than the earlier one and so it tagged along when I branched the post. I do not see where I can fix this. So sorry about that! It is a good answer. You can copy it and repost it back to the original conversation. There is a link at the top of this post back to the original.

Dave T

Hello namsp,

Since the screenshot of the hardware schematic only shows which GPIO pin one of the two switches you circled goes to, I will focus on that one. It is going into MP-5 and you have MP-5 properly connected so it should work for the Bass Boost.

The Toggle Cell is for a momentary switch that does not hold its state. A slide switch will hold its state for as long as it is kept at that setting. So you do not need to have it toggle. Remove the toggle cell.

Then the problem is that the MP-Pin input goes between zero and 1.0 in 5.23 format. The MUX requires and input of zero and 1 in 28.0 format. The solution is to use a Zero Comparator to translate the 1.0 into 28.0 format. The zero requires no translation.

Here is where you find it in the Tree Toolbox:

Here is how you use it:

I also suggest you turn on the Debounce. You have the invert button selected, you may need to change that.

Dave T