Unsped shield to non button boards

hardware

- CommentAuthorJP
- CommentTimeNov 17th 2008 edited
I've been digging around but can't find any information in a form I understand (I apologize for my lack of technical know how on electrics).

I have an unsped shield, which is ready to go, recognized in Arduinomeserial, all looks good, but I wanted to test wire it to an LED matrix from sprakfun - not the sparkfun button pad combos.

I had assumed that maybe if you open up monome test and light the top left led, that somewhere in the two banks of pins, two of them would become "hot" and all I would need to do was work out which one did which and wire that to the led matrix.

I posted a picture of the shield, with some notes...

http://flickr.com/photos/sykes/3036088971/

If anyone can give me a gentle nudge in the right direct that would be awesome.

For reference I'm using this LED matrix...

http://www.sparkfun.com/commerce/product_info.php?products_id=682

It seems simple enough, 2 sets of 8 pins make the LED's go on and off.
- CommentAuthorxndr
- CommentTimeNov 17th 2008
The pinout of those led matrix displays is a bit weird. Check the datasheet on the sparkfun site, page two.. Also make sure that you have the row/column pins right. Note that you might have to change your Rset resistor for the led driver to correspond with the low MCD value of the matrix.

I believe it had to be wired like this:

max chip digit pins > matrix column pins
max chip segment pins > matrix row pins

Good luck!
- CommentAuthorJP
- CommentTimeNov 17th 2008
| max chip digit pins > matrix column pins
| max chip segment pins > matrix row pins

Hmmm, not sure I fully understand what that means. If I'm looking at the shield, the top 16 pin has an IN in the bottom corner, that's the one I call A, the bottom one (nearest the breakoff board) has an Out, that's the one I'm calling B.

I'm assuming with monome test open and the top right LED clicked, I should get a different voltage on a meter between two of the pins in the headers.
- CommentAuthorphsr
- CommentTimeNov 17th 2008
I was thinking of doing the same thing, i just got 10 of those from ebay for $15. Let me know how it works out. I need to get my buttons back!!
- CommentAuthorJP
- CommentTimeNov 17th 2008
@phasor, it looks like it _should_ be easy, and at the very least it might be a super simple way to test that your shield is soldered correctly. Of course _should_ is never that easy. I'll document every step, as usual. ;-)
- CommentAuthorphsr
- CommentTimeNov 17th 2008
awesome, thanks!!!
- CommentAuthorJP
- CommentTimeNov 17th 2008
OK, still totally baffled. What's a silly simple way of testing that my shield is functioning? And then does anyone have an idiots guide to which two pins have voltage when the top left led is lit. Separate question, but I'm assuming just by shorting other pairs of pins I should get a button press registered. But nothing seems to fire. Is my assumption overly simple?
- CommentAuthorunsped
- CommentTimeNov 18th 2008 edited
its not a dumb question, since the inputs/outputs are multiplexed its a little tricky. i believe xndr's explanation is backwards on the rows/columns.

to test the max chip with the sparkfun (common cathode matrix)

[im not entirely sure on the order as im just looking at the schematic, so the display may end up mirrored on the x/y axiis]

(the positive side of the led's to the SEG pins on the max72xx chip)
connect led matrix pins: 5,6,7,8,9,10,11,12
to arduinome pins 2,4,6,8,10,12,14,16 on the "IN" connector

(the negative side of the led's to the DG pins on the max72xx chip)
connect led matrix pins: 1,2,3,4,21,22,23,24
to arduinome pins 2,4,6,8,10,12,14,16 on the "OUT" connector

the IN/OUT labeling is kinda goofy for reasons that are kind of complicated.
arduinome in = monome j_in
arduinome out = monome j_sel

use the osc_howto patch, and try sending frame/row data to test.

the buttons ... shorting 2 pins "should" give some erattic button presses but i cannot verify that.
- CommentAuthorJP
- CommentTimeNov 18th 2008 edited
edit2: So should I be able to put a meter on OUT 2 and IN 2 and if I get that LED triggered in a MAX patch, I should get a voltage on those two pins, that isn't there before?

edit3: Am I also correct in my assumption that the shield headers go...

08,07,06,05,04,03,02,01
16,15,14,13,12,11,10,09

or is it in fact

15,13,11,09,07,05,03,01
16,14,12,10,08,06,04,02

edit: OK lot of information there, I'll need to read that a couple of times and try some stuff out. Thanks !

Is it multiplexing on the breakoff header connections, i.e. the LED side of the chips? I'd assumed it was muxing between the arduino and the max, but once thru the max it would be providing a solid voltage for the LED's.
- CommentAuthorphsr
- CommentTimeNov 18th 2008
image?
- CommentAuthorJP
- CommentTimeNov 18th 2008
Image? You mean like this one... http://flickr.com/photos/sykes/3036088971/
- CommentAuthorphsr
- CommentTimeNov 18th 2008
I mean of the wiring that unsped is talking about. I can take pictures of my shield :-P
- CommentAuthorunsped
- CommentTimeNov 18th 2008 edited
idc headers go:

IN
15,13,11,09,07,05,03,01
16,14,12,10,08,06,04,02

OUT
02,04,06,08,10,12,14,16
01,03,05,07,09,11,13,15

as far as using a voltmeter? probably not, technically maybe, but it's more something an oscilloscope would be useful for. a voltmeter would probably give erroneous results as it's not really geared towards pulsing signals.

also the breakout board isn't electrically connected to the shield
- CommentAuthorJP
- CommentTimeNov 18th 2008
Yup, understand the breakoff isn't connected, I was using that more to describe the IDC headers coming off the sheild - I think we're talking the same thing.

So the voltage is pulsing? How come the LED's don't pulse? Or do they just super crazy fast? Thanks for holding my hand. :-)
- CommentAuthorunsped
- CommentTimeNov 18th 2008
the led's do pulse, just 'crazy' fast
- CommentAuthorJP
- CommentTimeNov 19th 2008 edited
Connecting any of the IN even numbers to any of the out even numbers with the arduinome+shield plugged in and arduionomeserial running and my test LED lights up - I have current. However this is whether the LED is "on or not" in the apps.

I'm assuming that means I have something wrong in my shield?
- CommentAuthorJP
- CommentTimeDec 12th 2008
Finally had a spare minute to debug what was happening before. I had my arduinome case open so I did some quick shield swapping and came to the quick conclusion that it wasn't the shield at all it was the Arduino.

Took me a good 20 minutes before it dawned on me to check for Arudino 12, and yes bingo I'd uploaded the firmware with the unsupported version. 55meg download of version 11 later, and I had the correct compilation uploaded and everything working as expected.

Your pin details above are spot on.

http://flickr.com/photos/sykes/3102188352/

Now I just need to solder up a couple of ribbon cables to the sparkfun led matrix and that side of the project will be done.

next step working out how I want to control this. I might experiement with the pots since I have them, then look at other options.

Thanks for yoru help Brad !!!
- CommentAuthorJP
- CommentTimeDec 12th 2008
I'm assuming that my idea of using potentiometers is a bad one for the button presses.

I tried just wiring to pins that would normally go to a button to one and giving it a twist and it's very not consistent.

Would I be better off finding an 8 (or 9) position rotary switch and just wiring that into the 8 pins, so it fakes a button press on each click?

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=KC18A10.001NLS-ND
- CommentAuthorJP
- CommentTimeDec 14th 2008
http://nomeist.com/knobome-display-working/140

Update. Display is all wired and working and I managed to cram everything into a tiny enclosure. All good, however there is no room for switches or knobs, so I'm thinking this will become a viewNome. Got some great comments on my blog from lyodMilligan (he of arcade button monome fame). Seems he might have a proto real knobome running. Just needs a bigger boat.
- CommentAuthorJP
- CommentTimeJan 7th 2009
http://nomeist.com/knobome-resurrected/154

I'm revisiting this idea.

"So my plan is simple.

I will attach 1 set of the 8 wires, to the 8 legs of an 8 position rotary switch. I will attach the other set of 8 wires to the legs of another 8 position rotary switch. I will then take the single out from the two switches and join them together at a momentary switch.

So using this little box, you will turn the two switches to the coordinates you want, and press the momentary button. That will trigger a button press at that coordinate."

Hopefully: simple, no software or firmware changes, bullet proof and easy?
- CommentAuthoroldanalogger
- CommentTimeJan 7th 2009
How did you get all the bits into the tiny case..? I've been planning a viewnome since I got a logic kit last year - got the display and also looked at building an led matrix with square ones - but the logic board is just too big to fit a hammond case. Which case did you use - any chance of an internal pic..?
- CommentAuthoroldanalogger
- CommentTimeJan 7th 2009
Ahhhhh...! Just looked at the vid - it's an arduiknobome.....!
- CommentAuthorJP
- CommentTimeJan 7th 2009
http://www.allelectronics.com/make-a-store/item/1591-CTBU/4.7-X-2.6-X-1.6-BLUE-TRANSLUCENT-CASE/-/1.html

I used this enclosure. It was silly tight. I actually had to shave the arduino board and the unsped shield to get it to fit. The Matrix works really well. I opened it up last night to take shots of the resistor network, and tied up a few things, and I'm fairly sure I have just enough space for a couple of rotary switches and a small momentary switch.

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Unsped shield to non button boards