www.megadrum.info

I started my build last night, got usb working with Medadrum Manager after driver installed, all looked fine.

Next I went to install my LCD which is a 2x20 HD44780 compatible LCD. I checked my wiring pinouts and pin 1 is VCC and pin 2 is VSS, which is swapped compared to other LCDs, all other pinouts are the same. I wired it up and got the backlight on but no characters, I tried messing around with contrast inside MDM but nothing helped. When I pressed the buttons on my Megadrum I could see faint movement on the LCD but that was it, like garbage but very unclear.

Then when I was disconnecting the LCD I accidently touched pin 1 and 2 together while connected to the Megadrum. Now I cannot communicate with it any more through MDM, but Windows sees it when I plug it in and installs the driver when I try a different USB on my PC and the little LED flickers when I am in MDM and click "Get All".

I cannot see the Firmware version in MDM any more though which is why I am worried. I haven't started my pad connectors yet so I cant even test through SD or AD plugins.

I checked the underside of my board and everything *looks* ok. I feel really stupid....

It's very hard to tell. If the MIDI LED flashes when you do 'GetAll' then at least MIDI data get from the PC to Atmega.
Try touching some of the inputs (the MIDI LED should flash as well) while watching for MIDI data in the MIDI Log. There you should see some data coming from MegaDrum.
You may also have accidentally changed Atmega CPU clock or USB MIDI Speed while blindly navigating the Menu.

Thanks Dmitri

You were right about me pressing the keys blindly, I must have changed something. The good news is that the button schematic that I made works! Haha

So I switched off MD, held down the right button and switched on.

Works perfectly now thanks Dmitri!! Here is a picture with a piezo connected to one of the pad connectors through MDM.

All that is left now is for the right LCD to come along.

My build should be finished by next week, will share more as I go.

Thanks