Buttonboard with LEDs

MIDIbox NG
1

Hi 

I have a question regarding the NG App. 

I have a bunch of Buttons that have a wrong layout of the LEDs. They are Parallel with different direction.

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Now i asked the friends of microkontroller.net for advice and they say that it is possible to make a Array with a 74HCT595 and let them work in a H-Bridge way together and Pulse the two LEDs from each direction. 

 

Is that possible to do with the NG App?

 

Thanks

Novski

 

edit: this is the link. Its German sorry for those who don’t understand… http://www.mikrocontroller.net/topic/335089?goto=3674282#3674282

2

If you (or TK) wrote a modified driver this was absolutely possible.

3

Did anybody ever use a Charly circuit with Midibox? Seams to be quite powerful…

 

http://en.wikipedia.org/wiki/Charlieplexing#Charlieplexing

4

you want to light both LED at same time with fast pulse ?

I just ask because you will have yellow colour :rolleyes:

5

Yes. That wold be great! To get a Color for each Button. Mute, Solo, Select…

6

Regarding the German discussion i linked above i now know:

Charlyplexing is not possible with HC595 because the Tristate OE! is one signal for all outputs. I didn’t find a Chip with multiple OE until now. Exept makting a uC working as a HC595 there is no solution for this…

 

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best regards

novski

7

Regarding this Button that i can’t use i made my decision to use the Sparkfun Button Pads again.

 

I now have some questions to RGB LEDs wiring. I want to use 3 Color LEDs. I can’t find much information about that quite new feature. 

A found a drawing from Protodeck http://www.midibox.org/dokuwiki/lib/exe/detail.php?id=protodeck&media=protodeck:ledsdout.png

But i think it should be easier somehow without those NPN Transistors driving the Selection Lines. Did i mis a schematic somewhere or is there no documentation available yet?

 

Thanks for a hint..

novski

8

The usage of source drivers (the transistors) is for pro users who want to get perfect results.

I’m unsure if this really makes a big difference.

It’s more important that you try to keep the number of selection lines per matrix as low as possible (8 is acceptable, 4 is perfect)

 

Best Regards, Thorsten.

9

Thanks TK.

I looked trou the parameters of NG .NGC and was surprised how much was added since i read that last time! Thats really a great work. Thank you so much.

 

i will have 3 selection lines and 8 rows with each color to get 24 RGB Backlit Buttons.

 

I didn’t find a parameter to set the number of selection lines in the .NGC..?

necessary?

 

best regards

novski

10

ok. I tried a bit around today but can’t figure out how that all works.

I added a DOUT4 to my core and took one resistor Array out of it by making short connections where the Array resistor was before. Then i added this code to my NGC file:

test D-OUT Matrix

DOUT_MATRIX n=2 rows=8 mirrored_row=0 inverted_sel=0 sr_dout_sel1=1 sr_dout_sel2=0 sr_dout_r1=2 sr_dout_r2=0

i connected a LED to D0 of SR3 (Cathode) and D0 SR4 (Anode). I loaded that code to my Core and the LED went ON.

I was surprised.

Then i tried to find out the command to lit a LED one by one and found that the normal LED comand: “EVENT_LED id=999 hw_id=16 value=127” makes i go dark. Value=0 makes it go on.

Can somebody explane me why its hw_id=16 and not 8 ?

Im confused

thanks

novksi

11

made new post because nobody reacted.