Sparkfun buttons: Matrix possible?

MIDIbox NG
1

Hey,

 

I’m thinking of using this buttons in my next ucapps project:

https://www.sparkfun.com/products/9277

 

From the schematic it seems, that they already designed for use in a matrix. But when I compare the schematic of the button pad with the one from the DIN module, it seems, that they did it the other way around. The button pads don’t have a groundline, but the inputs of all buttons are connected.

Is it possible to use the button-matrix of the NG anyway or do I have to connect each button separately? Can I use the “inverted” parameter in the NG for this application?

 

Thanks,

Chris

2

Hi Chris,

 

what they call “GND1/2/3/4” are actually the selection lines, provided by a DOUT SR which has been assigned with sr_dout_sel1=<number>

 

The other side of the switches will be connected to a single DIN input.

 

Best Regards, Thorsten.

3

Hey TK,

 

thanks for the reply! 

Now I know how to use them… will be great.

 

Best,

Chris

4

I have this running.

It works well!

 

but be carefull if you layout your own board. The Library files contain several different versions and i chose the wrong one in my first Layout… 

br,novski

5

Hey,

 

I use the 2x2 boards from sparkfun without creating a layout for my own pcb.