DOUT Led Always On

[birdsofmyneighborhood]

Hi guys!

So I'm working on my midibox128 prototype and I'm having an issue with my dout module.  My LED always stays lit, no matter which pin it's connected to or which midi messages I send to the board.

I can actually toggle the led on/off by touching the 'SO' connection pin with a lead from my voltmeter...not sure why that is.  Does that mean incorrect signals are coming across from core?

Any ideas?  My solderings look alright, but that still could be it (I'm a beginner).  My DIN module works ok, so I'm not sure if it's a problem with the core board or what.  Other posts related to this seemed to stem from having a fully loaded board, whereas mine isn't - 99% chance that I just messed up somewhere.

Thanks a lot!!

- Dusty

[sparx]

Hi

OK, I had this and was pulling my hair out with it, if you are using a header socket, change it for another one.

If not, resolder the cable.

HTH

Sparx

[stryd_one]

My LED always stays lit

One, or all of them?

I can actually toggle the led on/off by touching the 'SO' connection pin with a lead from my voltmeter...not sure why that is. Does that mean incorrect signals are coming across from core?

SO means serial output, I guess you are shorting the SO pin from the core, to ground - no data is sent when you do that... but yes, it could indicate a problem with the connection between that pin on the DOUT, and the core, as it suggests that the LED is lit because it's told to be lit (you're preventing that signal from arriving if it's pulled low by the voltmeter). Look for a short between a positive rail like Vss, and the SO pin...

You should try the SRIO interconnection test app. Don't forget to upload it with the latest version of mios studio in smart mode with 'wait for upload request' turned on. Read the readme file and source code comments for instructions, and when you test the lines, test them at various points (on the PIC, on the pad, on the jumper, on the input and output of each DOUT)

HTH!

[birdsofmyneighborhood]

Good news!

All SRIO tests were successful:

  - Mod 0:  DOUT:J1:SO was 8v, DOUT:J1:SC and DOUT:J1:RC were 0v

  - Mod 1:  DOUT:J1:SC was 8v, DOUT:J1:SO and DOUT:J1:RC were 0v

  - Mod 2:  DOUT:J1:RC was 8v, DOUT:J1:SC and DOUT:J1:SO were 0v

I also tested at other places, like the PIC and jumper like you suggested.

I think I found an issue though, while looking at the schematics to do this test.  Here is DOUT:J1:

Notice that the left-hand SO and the right-hand SO are not connected, which is different than all of the other pins on J1.  I didn't notice this originally.  The left-hand SO goes to J2 while the right SO goes to IC1.  Should I connect the 5 pins on Core:J8 to all 10 pins of DOUT:J1?  Right now I only have Core:J8 connected to the 5 left-hand side pins of DOUT:J1.

Let me know if I'm not being clear...basically I just need to know how to properly wire the core board to dout.  I guess that each pin on Core:J8 should actually be connected to 2 pins on DOUT:j1, unlike how I have it now.

[birdsofmyneighborhood]

Ok, problem solved!  I simpled wired the two SO pins on DOUT:J1 together, and it works!

There is one thing though...right now my LED is connected to J3:D1, which under standard midibox128 should respond to the midi message

   90 31 7f

because it is pin #2.  However, it only responds to

   90 36 7f

so it's acting like pin #7.  Are the pins labelled wrong or something?

Thanks everyone for the help!!

[stryd_one]

Err, those pins are meant to be separated so that the DIN and DOUT modules can sit on the same physical chain. Maybe you cabled it wrong? Although I seem to remember smash reporting an error like this on one of his boards, maybe it's that?

You need to count the pins backwards Re: DOUT pins backwards? ;)