Troubleshooting Help

[jman 31]

Are the input jack boards your own design or is that something Dmitri did? If you did it, are you sure of your design?

[primal65]

Hi, Jman. They're my own design. I used Kicad. I basically just followed dmitri's input schematic and routed a board. I've checked all traces for breaks and bridges. All seems good. One board has 8 inputs routed to a pin header. The plug for that goes to a second board which has the other 8 inputs and all traces are routed to another header which carries them all off to the analogue board. I have the hihat pedal input unmouted. That input jack is wired to a switch and all fed back in to the second board via a 4 pin whose traces all lead to the main jack that goes to the analogue board.

I know I made it overly complicated by not mounting the hihat pedal to one of the boards, but the enclosure I had in mind would only allow 2 rows of 8 so I was just gonna run the hihat pedal input somewhere else.

It's getting very hard to pinpoint this problem. I've followed all the advice and everything seems fine. Another thing is that my MD seems to not be consistent in it's problems. For instance, at one moment my led will be lit yet I get no midi activity in midi-ox. Another moment I'll get controller message spam and sometimes midi note spam. I"ll unplug the analogue board and the led will stay lit, and another time it will go off an on when I unplug and replug that board.

A few times I've gotten pads to actually trigger some midi notes in midi-ox, but most of the time I get nothing from the pads.

On a side note, when the VU meters are showing on the LCD, some of them will be lit fully, but they will all go back to normal when I unplug the analogue board.

I use to consider myself a good troubleshooter, but I'm about to slice my throat trying to figure this out

[primal65]

I don't want any of you to think I'm expecting some miracle diagnosis from you. I realize it's extremely hard to give advice when you can't physically work with my MD yourself, so please don't take my rambling that way. I'm just throwing out any info I have. I do appreciate the replies I've gotten. I'll do my bests to keep troubleshooting it.

[primal65]

If I were to completely unplug the analogue board, keyboard, and encoders, leaving only the digital board and lcd, should everything look kosher on the VU meter? No full bars on the LCD, etc? This is assuming the digital board was working probably. I know I need the other stuff to operate it. I'm just trying to rule out the digital board as the problem.


More food for thought: When I originally plugged in my icsp cord to program the pic I put it in backwards. I wonder if this could have damaged something. I switched the plug around and got the pic programmed and the MD usb popped up, but who knows.

[jman 31]

I would try to ascertain which board has a problem by adding them one at a time. If you get no problems when you don't have the inputs board attached, then I would add it and see if they crop up. Your VU meter should show only underscores with one solid box in the upper left corner when it is all hooked up but with no triggers attached. So For instance, you don't need the encoders attached to check the inputs PCB and so on. Attach items until the problem returns and then at least you will know exactly which PCB holds the problem.

[Firelord]

A few times I've gotten pads to actually trigger some midi notes in midi-ox, but most of the time I get nothing from the pads.

Describe this in more detail. If you see MIDI activity on MegaDrum but no MIDI messages show up in MIDI-OX then you might have problems with MIDI-USB stability. That is if you're using USB.

[primal65]

I would try to ascertain which board has a problem by adding them one at a time. If you get no problems when you don't have the inputs board attached, then I would add it and see if they crop up. Your VU meter should show only underscores with one solid box in the upper left corner when it is all hooked up but with no triggers attached. So For instance, you don't need the encoders attached to check the inputs PCB and so on. Attach items until the problem returns and then at least you will know exactly which PCB holds the problem.

At the moment with nothing but the LCD plugged into the digital board (and the usb of course) I see the 1 VU meter in the top left corner fully lit, and the rest underscores.

Describe this in more detail. If you see MIDI activity on MegaDrum but no MIDI messages show up in MIDI-OX then you might have problems with MIDI-USB stability. That is if you're using USB.

At times the led will remain lit as if there's activity( this is when I'm doing nothing, hitting pads..etc.) but no activity shows up in midi-ox. Yes, I'm using usb.

[jman 31]

I would try to ascertain which board has a problem by adding them one at a time. If you get no problems when you don't have the inputs board attached, then I would add it and see if they crop up. Your VU meter should show only underscores with one solid box in the upper left corner when it is all hooked up but with no triggers attached. So For instance, you don't need the encoders attached to check the inputs PCB and so on. Attach items until the problem returns and then at least you will know exactly which PCB holds the problem.

At the moment with nothing but the LCD plugged into the digital board (and the usb of course) I see the 1 VU meter in the top left corner fully lit, and the rest underscores.

OK that is as it should be. Now add another board and see if it remains the same. Keep doing that until you find which one makes you VU meter get wanky.

[primal65]

I've made some significant progress I think. My problems seem to be stemming a lot from my hihat pedal. I plugged a regular pad into the hihat and it started working, mostly. I then plugged a few other pads in and they seem to be working as well. They are sending messages into midi-ox, the VU meters are bouncing up and down like they should be when I hit the pads. Only thing is, they all seem to be sending the same note: 63.

I wonder what it is about my hi hat pedal that MD doesn't like. My kit is a cheapie osp set, but it works great when just connected through the shitty module it came with and out to midi into my computer. I have the impedance toggle switch on MD. I've tried in both positions and it doesn't seem to do anything. Guess I'll have to work on this now.

[primal65]

AHHHHHHHHHHHHHHHHHHHHHHHHH

Ok, so I've fixed it and I'm embarrassed to reveal what the problem was....but I will as a reminder to others:

Make sure your ribbon cables are not switched around between your input board and analogue board(or between any boards for that matter).


Thanks to Firelord and Jman for their much appreciated assistance in solving this debacle.

I'm off to play with my Megadrum for now.

Regards, Primal