MegaDrum 56 inputs latest schematic and PCB

[jjpl2001]

Use components values as shown in the schematics unless you know you can use different values. After that test it again and describe the problem if it's still there. 99% chance is you have a short or a break somewhere on the board.

Thanks. I was using an old firmware, So I have to program it via AvrDude. It was a mistake in the Low Fuse Bits. I was using lfuse:w:0xE2:m instead of lfuse:w:0xF7:m. So the Mega644 worked fine. The 18F2550 works fine but serial comunication was runiing at bad speeds.

[operators123]

Really noob questions incoming but I'm going to ask them anyway,
how many 1/4" input jacks do you use with this? I'm a bit confused as to how the piezo sensors on my DIY drum pads will connect. For my snare drum pad, I have a piezo sensor underneath it that has a female jack connected. Am I correct in saying a 1/4" stereo lead then connects these to another female jack on the megadrum module? I then have how many female jacks on this module. I've seen someone say before it was 30, but then how is this 56 inputs?

Also can somebody point me as to where I can find a 'CONN_8X2'? I can't seem to find it anywhere.

[airflamesred]

Welcome
32 and 56 refer to the amount of mono inputs. If you're constructing it yourself you can wire it how you like.

I don't have the foggiest what a CONN_8X2 is

[dmitri]

All jacks, except the Kick jack, on MegaDrum modules built by me are stereo so you can connect two single zone pads to a single jack using a Y-splitter cable.

[operators123]

Oh right so for example I could have a snare and a tom going into a single stereo input on the module using a 1/4" Y-splitter?
I'm still confused though about how many input jacks I have on the module, is it 30 stereo input jacks? - which would then mean 60 mono inputs?

And another question, I've heard I can't just buy any atmega644 chip, I need to buy a special one with a protected bootloder or something like that, is this true? And where can I get one from

[angr77]

Hi!

Each stereo input could be used as two single inputs and with no realation to each other.

The 56 input model have 28 stereo inputs...(but the kick, hihat pedal are dedicated to one single input)

ATMEGA 644 can be bought here at the forum from Dmitri. It is protected, so if you want use all firmare goodies you should definitive buy a chip from Dmitri. (we are talking about 30-40 major firmware updates since the days of the unprotected firmware)

(Please help me to understan why everybody are loolking for the 644 chip...when the 1284 is available and has more power etc. If you really want to play drums...buy a complete ARM based board from Dmitri)

Angr77

[operators123]

Right I see, 28 stereo audio jack inputs and one of those have to be dedicated to the high hat pedal and kick.

Thanks for the information

Also CONN_8X2 is a 16 pin connector that connects to the LCD (P2 on the schematic), I can't seem to find it anywhere.

[operators123]

Quick question, if I used a atmega32-16PU with this design and a 20mhz crystal would that still work?

[ignotus]

It'd probably work but you'd be overclocking it.

Bear in mind that if you use that one you'll have to stick to the last unencrypted firmware (over 3 years old). I reckon it's worth it to get one off Dmitri so you can keep it up to date.

[operators123]

Is overclocking it an issue? there's a 4mhz diffirence between what the chip is and the crystal