LED Button Matrix

[Echopraxia]

Here I go again. :whistle:

Just trying to understand the wiring of the LED Button Matrix.

Looking at the DIN diagram it has J8 D1 being split to 4 wires then each of the split wires goes to a separate 1N4148 diode then to the matrix row buttons and then from the buttons straight to the DOUT board J4 D2-D5. Am I right so far?

Then the led cathodes get wired to the same J4 D2-D5 on the DOUT but go before the resistors? Is this correct?

I am lucky I have some spare diodes from Wilba's seq build and I believe they are the same kind.

So from the DIN board J8 D1, I can take one wire and use a wire stripper to make 4 points on it to solder diodes to?

Like this (starts at the bottom and goes up)(please excuse my poor wannabe spreadsheet. Its supposed to be 4x columns)

To DOUT J4________D2___D3__D4__D5

Row buttons________^____^____^____^

Diodes 1-4_________1____2___3____4

From DIN J8 D1>-------^------^-------^--------^ <--- this is the ribbon cable with the (^) being stripped bare wire.

My last question for now is, does the LED Matrix get wired to the ground like the other LEDs? Looking at the DOUT diagram they appear not to be connected to ground.

I probably should invest in a cheap breadboard to test this.

Regards,

echo

[sparx]

Yes, it looks like you got it!

There is no ground for these LED's, its provided by J4 and the output of those 4 pins goes to the DIn board via the diodes.

[Echopraxia]

Sweet.

I'll post results.

[Echopraxia]

I am in the middle of finally testing the matrix out. I wanted to ask a question before I got to far along.

I ended up not having enough leds to complete the matrix for now :( but my question is regarding the 4 row buttons which I cannot get to work yet.

I have all 4 row buttons completely wired up right now. I have the DIN J8 D1 going to all 4 row buttons. It is one wire striped along the way with the cable ending at row button #4 (does #4 being at the end matter?) Next I have the black stripe end of the diodes placed directly next to each respective button's pin and din wire to solder them altogether easily. Then I also have the DOUT J4 D2, D3, D4 and D5 cables ran to these same spots on row 1, 2, 3 and 4. So all four connections (DOUT,DIN,diode and button) are sandwiched ontop of each other. Is this ok or do the components need to be seperated so the transfer of electricity is streamlined?

I tried wiring up at least two leds and I get the first one to light at start-up but when I press any of the row buttons the led goes out and if I press any of them I get no led light. Is this normal for this stage in wiring? No leds are soldered yet.

Regards,

echo

Edited August 20, 2010 by Echopraxia

[Echopraxia]

just to add to my previous question.

I am reading about diodes and see that electricity goes one way in them. It starts from the non striped side (anode) and goes to the striped side (cathode. So from understanding this now, should I connect the first row button to the anode side of the diode and connect the cathode side to the DOUT input or vice versa?

As of now I have ground ran to the anode side of the diodes and the cathode (striped) side ran to the button AND the DOUT. The reason for doing this happened because I was looking at Wilba's diode placment on the mbseq pcb of his and thought I saw only the striped side being connected to something but now I see that the anode side is connected to something too! So I guess that why its not working. The diodes should still be functional yes? Or should I put new diodes in.

I will try to mess with this later tonight and post results.

Edited August 20, 2010 by Echopraxia

[Echopraxia]

OK. I still have no success.

I rewired the button diodes. I have the buttons wired straight to the DIN J8 D1 and the diodes anode (non-striped side) connected to the button also. I reversed the diodes so the black stripe is on the DOUT side now. The cathode (striped side) of each diode is wired to one of the DOUT D5, D4, D3 and D2. Is this not correct? All the buttons do not work. I used fresh diodes just to make sure. I don't need to have any of the leds wired for these buttons to work correct? My veroboard can't take much more desoldering so I can maybe get one more shot before I'm back to the dremel :wacko:

Do I need to reverse the diodes? i.e have the diodes striped side (cathode) connected to the button and the non-striped side (anode) wired to the DOUT?

[Echopraxia]

I'm gonna be writing a book by the time I'm done with this.

Row #1 has instrument, release, WT, User4 and Frq correct? Or is row #1 Volume, attack, LFO1, User1,BD, Mod/Carrier?

I reversed the diodes so the striped end is connected directly to the button and the non-striped end is going to the DOUT board. My vero board is practically toast. I'll probably be at this for a couple days.

Should of bought that breadboard tester :rolleyes:

Still no luck. Any suggestions.

Edited August 21, 2010 by Echopraxia

[Echopraxia]

Not like I've asked enough questions already, but.

On the diagram for the DIN, the cable goes into the button and the button goes into the diode and the other end of the diode goes into the DOUT connection? My first post here indicated that the diode went first from the DIN board and then the button followed and directly from the button to the DOUT connection.

Which one is right or are they both wrong?

[Janis1279]

just to add to my previous question.

I am reading about diodes and see that electricity goes one way in them. It starts from the non striped side (anode) and goes to the striped side (cathode. So from understanding this now, should I connect the first row button to the anode side of the diode and connect the cathode side to the DOUT input or ...?

Hi echo

Not any or... !

But are your leds are connected with it's longer legs to the DOUTX4 J4:D1,D0 and J5:D7,D6,D5,D4 pins ( in each column 4 x leds with longer pins connected together ).

Regards,

Janis

Edited August 21, 2010 by Janis1279

[Echopraxia]

Not any or... !

But are your leds are connected with it's longer legs to the DOUTX4 J4:D1,D0 and J5:D7,D6,D5,D4 pins ( in each column 4 x leds with longer pins connected together ).

I do not have any leds wired yet. Another question I had was, do the leds need to be wired up for the row buttons to work? I am just trying to get the row buttons working. Where do the diodes go? the schematic of the DIN board shows diodes going in the middle between the row buttons and the DOUT J4 D2,D3,D4,D5. Or am I reading it wrong?

Edited August 21, 2010 by Echopraxia

[Janis1279]

I do not have any leds wired yet. Another question I had was, do the leds need to be wired up for the row buttons to work? I am just trying to get the row buttons working. Where do the diodes go? the schematic of the DIN board shows diodes going in the middle between the row buttons and the DOUT J4 D2,D3,D4,D5. Or am I reading it wrong?

I may be wrong, but leds don't be wired for correct row buttons work.

diodes of the DIN board are connected : R1 to the green coloured wire R1on the DOUT board, R2 to the green coloured wire R2 on the DOUT board etc.

By default MB FM uses The third SR of DIN board for the row matrix buttons .

Regards,

Janis

Edited August 21, 2010 by Janis1279

[Echopraxia]

diodes of the DIN board are connected : R1 to the green coloured wire R1on the DOUT board, R2 to the green coloured wire R2 on the DOUT board etc.

Do the diodes go before the buttons or after the buttons? These diodes are not on the DIN or DOUT board already right? The DIN diagram looks like the diodes go after the buttons then from the diodes cathode side (striped) to the DOUT connection. I tried this with the buttons before the diodes and I am thinking my only choice now is to try the diodes before the buttons. Maybe someone has a picture of what a working row button section looks like?

Thanks for your responses

Edited August 22, 2010 by Echopraxia

[Janis1279]

Do the diodes go before the buttons or after the buttons? These diodes are not on the DIN or DOUT board already right? The DIN diagram looks like the diodes go after the buttons then from the diodes cathode side (striped) to the DOUT connection. I tried this with the buttons before the diodes and I am thinking my only choice now is to try the diodes before the buttons. Maybe someone has a picture of what a working row button section looks like?

Thanks for your responses

The 4x row button diodes are additional diodes to DIN and DOUT diagrams.

The Led button module part is custom maded and a picture not give a more clearer view , anyway. But these 4 diodes are included in my module.

p.s. When I have interest to build or better understand for me any diagrams, schems etc. I am printing or drawing its,always. And then I look its many times if it needed .

Regards,

Janis

[Echopraxia]

I have the buttons wired straight to the DIN J8 D1 and the diodes anodes (non-striped side) connected to these buttons also. The cathode (striped side) of each diode is wired to one of the DOUT J4 D5, D4, D3 and D2. Is this not correct? All the buttons do not work.

Should I rewire the diodes anode side (non-striped) to DIN J8 D1 and then put the button on the cathode side (stiped) of the diode? Then also put the DOUT J4 D5 on a button and so forth?

[Janis1279]

I have the buttons wired straight to the DIN J8 D1 and the diodes anodes (non-striped side) connected to these buttons also. The cathode (striped side) of each diode is wired to one of the DOUT J4 D5, D4, D3 and D2. Is this not correct? All the buttons do not work.

These connections are correct.

The better way to understand how the button matrix works, you need connect all 4x 6 buttons. Without leds, of course.

Should I rewire the diodes anode side (non-striped) to DIN J8 D1 and then put the button on the cathode side (stiped) of the diode? Then also put the DOUT J4 D5 on a button and so forth?

Why ?

Regards,

Janis

[Echopraxia]

These connections are correct.

The better way to understand how the button matrix works, you need connect all 4x 6 buttons. Without leds, of course.

I do have all 4x6 buttons connected but It was not working this way. This is why I am confused. Thank you for letting me know I had the schematic correct. I will try again. Maybe my buttons are bad? Only one row button worked. All my column buttons work, those are the easy ones :). I will have to do more error testing.

Why?

I do not know very much about diodes and was not sure if they needed to go before the buttons or after.

Edited August 22, 2010 by Echopraxia

[Echopraxia]

Alright I tested some more and am still confused. I was able to get two row buttons working at most but when I had more hooked up I was only able to access one row. I tried another set of buttons and same thing. I was also having behavior where one button would work, then it wouldn't without changing anything. I am ordering a breadboard tonight so I can figure this out without soldering myself silly.

[Echopraxia]

I got breadboard in but not much help :(

Here is a picture of what I thought to be correct. Isn't it this simple?

I am going to check my soldering and idc connectors when I get a chance but if someone could at least tell me that this is a correct connection diagram I would be grateful.

Please excuse the kindergarten picture.

Do the leds cathodes have to be wired up at the DOUT J4 D2,3,4,5 (before the resistors) for these row buttons to work?

Edited August 27, 2010 by Echopraxia

[Janis1279]

Every row button have a 1 NO contact.

[Echopraxia]

Every row button have a 1 NO contact.

So no ground is correct? Thanks Janis!

[Echopraxia]

Still no luck :(

My soldering is good and my idc connectors are good.

I wired the row buttons like in the Janis' picture without any grounds (Vs) and get no response from any of the row buttons. Do I have to have a ground somewhere?

I still have not yet wired the leds yet (if this matters)

Are the diodes in the right direction?

i am at the point where I wanna take an extra DIN module and reprogram the hex file to hook up 4 lousy buttons to it. :cry: And I also don't have any room in the case for it. :no:

[Echopraxia]

I started testing voltages on my DOUT modules and noticed I am getting 3.6v on one pin on my J4 shift register and another pin on J4 is only getting 1.6v. I took out the shift register and tested the socket and came up with 4.8v. I put another shift register in but same voltage drops occurred. I looked at the DOUT schematic but it only had 5v on a couple pins and I am getting more like 4-6 pins with 4.8v on each register. I had another DOUT board lying around but my bad luck, J4 was already striped of its resitor network back when I was gonna use a 3 digit led BPM for my v3 MBSEQ., so I can't use the other DOUT board to test.

Can someone tell me what voltages I should get on the J4 register of the DOUT board? I seem to be getting different voltages on the different shift registers.

When I have time I will upload the DOUT test app. And I will also edit the tables to use another register than J4 for the row buttons.

[Echopraxia]

attached an image of taximans row buttons for reference.

Edited September 6, 2010 by Echopraxia

[TK.]

It's normal that you won't measure 5V at an DOUT pin which is used to control a LED and/or button matrix with a common multimeter, as the output patterns are changing with high frequency.

And even worse: if somebody would tell you the voltages that he measures at J4 with his multimeter, you would measure different values with your multimeter - because multimeters are just not made to test waveforms...

By reading this thread is hard to understand the current state

- are the buttons working? (does the menu page change when a button is pressed?)

- are the LEDs working? Is only a single LED enabled (thats the expected behaviour) or are multiple LEDs enabled (this would indicate a wiring error).

Sometimes you are asking if the schematics are correct, or you are asking questions (such as "ground connection?" or "cathodes before resistors?") which are definitely documented in the schematic (to answer these questions: no and yes)

I can confirm that the schematics are correct!

http://www.ucapps.de/midibox_fm/mbfm_din_default.pdf

http://www.ucapps.de/midibox_fm/mbfm_dout_default.pdf

Best Regards, Thorsten.

[Echopraxia]

I'm pretty sure by now that I have the connections correct. I need to now find the fault in my soldering or idc connectors or something else.