www.megadrum.info

Hello,
today I 've discovered some really strange thing to happen.
I've connected MIDI keyboard into MIDI in port of my MD and I was monitoring it with the midi-ox. When it was connected to computer using MIDI out port everything was working good, but when I have connected MD via USB and see what it has on input, then there was much data missing. For example missing midi off messages in case of fast hitting, only when the key was pressed for longer time, releasing was causing MIDI off message. Also messages like pitch bend and modulation were very innacurate. But when it comes to trigger from pads inputs - everything is working very good, without any delay. Is this normal?
BR
Michal

I haven't tested MIDI through functionality extensively since it has rarely been used. Two things might be at fault:
1. An error in my code.
2. An electrical problem on MIDI In (6n138 and etc)

Can anybody else confirm experiencing same problem?

I think there is no problem on MIDI in, because it is routing ok to MIDI out...
BR
Michal

zaklinacz wrote:I think there is no problem on MIDI in, because it is routing ok to MIDI out...
BR
Michal

It could be that 6n138 might be missing some bits from time to time if the MIDI signal is just about strong enough to trigger it due to variation in value of resistors. This is why I'm asking others to confirm the problem.

This is my experience
I'm using megadrum (a Synthex kit V3.1) in the same box with a miduino board (= midi arduino). When I've tried to connect the midiOut of the miduino to the midiIn of MD, it doesn't work properly (wrong CC number appears some time, missing values). So i've connect the midiout of MD to midiIn of miduino and since this time everything is good.
I haven't done some other try but it seems that in my MD, there's an issue with the midiIn.
The issue has appeared using midi connection, not with USB (I haven't try with the USB connection, it may work or not, I can do some tests if it could help)

I forgot to add: I'm using Synthex 3.1.
BR
Michal

Just tested MIDI through functionality with a 56 inputs module and a Novation Remote 25. Didn't miss any Notes On/Off messages no matter how fast I played all the keys. Didn't miss any Change Control or Pitch Bend messages when moving the Pitch/Mod joystick of the keyboard around like crazy.
The module I tested with is Atmega644 based at 20MHz with 6n138 as a MIDI In optocoupler.

I'm not missing anything when MD is connected to other device (or computer) by MIDI out, but only when using USB connection. Optocoupler then should be ok, because from midi in to out everything is working good. I'm also running Atmega 644@20MHz
What could be wrong?
BR
Michal

I've tested with a module which uses PIC18F13K50 with the firmware I posted in viewtopic.php?f=3&t=702 . Make sure your PIC uses the same firmware for the USB MIDI.

And what if my PIC is 18F14K50? will this firmware be ok also for this one?
EDIT: ok, stupid question:-) already found answer.
BR
Michal