Cycle EQ and LEDs

RichThompson Question

Jul 16, 2015 00:00

Hi

Hoping someone can help me one what's probably very simple to achieve!

I have an ADAU1701mini dev board. I'm loving it but I'm stuck.

I'm trying to setup a single push button to cycle through four different preset EQ's and also light one of four leds to show which is selected.

I've set up four simple parametric EQ's with an index selectable multiplexer tied to a GPIO. Now I want to turn on one of four leds each on a separate GPIO but I have no idea how to tie the two together.

I'm also a bit stumped on adding a clip led, but I notice some discussions on this already so I'll go read those.

thanks

Rich

Report

KJBob Reply

Jul 17, 2015 00:00

Hello Rich,

You can use an index demultiplexer to send a logic "high" to one of several GPIOs, using the same index as for your filter mux. Since the ADAU1701MINIZ board has only three LEDs, I made darkness represent the lowest index. See the lower right corner of the schematic below:

BTW, you might consider replacing your multiple filters and mux with an index-lookup filter, which is ready-made for this purpose. The index filter saves instructions, since its index chooses between parameters for just one filter, instead of selecting an output from among several filters running in parallel. An example is shown below. The toolbox includes several flavors of these index-lookup filters, so go ahead and try them to see which suits your application the best.

Best regards,

Bob

6c60960f3baac1c2e206b05f2a95c1e1.png-620x415.png

b393790ba46f6b7df62bc8f8970fe907.png-524x403.png