MegaDrum 56 inputs latest schematic and PCB

[dmitri]

This is a schematic and a PCB for a single board MegaDrum 56 inputs with 4851 MUXers.

schematic_small.png

components_small.png

All KiCad and PDF files in one zip file:

megadrum 56 DIP kicad.zip

Warning!
To the best of my knowledge the schematic and the PCB are correct but it has not been tested by me.

1. EEPROM chip (24C256), PIC18F2550 and 6N138 are optional depending on your requirements.
2. Schematics for LCD and controls are the same as in viewtopic.php?f=3&t=266
3. Pinout of the pads connectors is the same as in MegaDrum Kits in viewtopic.php?f=3&t=1420

[sanik_s]

Good work! Please stick this topic.

[peti13]

Hi! I've already build an old version of the Megadrum, but now I want to try something else. This PCB looks good, I want to test it, but I have a question. I've already got an ATMEGA32. Could it be good to an equalent for the ATMEGA644? And which firmware is compatible with this? (sorry for my bad english)

[dédé]

Hi,

This one looks great.
Is it the next Megadrum 56i version ?

[dmitri]

The only reason for this topic is that people kept asking for a one sided single board PCB layout which uses 4851 multiplexers but nobody had time/skills to amend the Analogue/Digital PCBs and share the results.

[Krisbo]

Hi guys, I'm new to this forum and somewhat new to electronics. I've been modifying microphones for some time now so I have a basic understanding although microphone schematics are vastly more simple than these projects.

I'm going to have a crack at building the design in this thread. Am I correct in that this in now an amalgamation of the old analogue board/digital board design?

One more thing, does anyone happen to have a pdf of the pcb to connect this board to an input board with pcb mounted jacks?

Thanks, I'll be sure to update you guys with my progress

Kris

[Krisbo]

Actually, I'm a little stumped by the concept of this board. If it is designed to replace the separate analogue/digital design, where is the USB connector? Also, I can't see where the DIN5 is on either design.

Little help?

EDIT: I think I may have figured it out. Is CN2 for buttons, CN3 for rotary encoders, CN5 for the MIDI, CN6 for USB? If that is the case, what do CN1 and CN 4 connect to?

EDIT #2: Am I also correct in assuming that BAT85 diodes are no longer a part of the design?

Thanks!

[dmitri]

EDIT: I think I may have figured it out. Is CN2 for buttons, CN3 for rotary encoders, CN5 for the MIDI, CN6 for USB? If that is the case, what do CN1 and CN 4 connect to?

Why did you have to figure it out if you have a schematic and:

3. Pinout of the pads connectors is the same as in MegaDrum Kits in viewtopic.php?f=3&t=1420

?

[Johnfreeth]

CN1 & CN4 are for the programming cables see the bottom of this link:
http://www.megadrum.info/schematics.php

Bat85 diodes are not used in this design but make sure that you use 4851 IC's and NOT 4051

[Krisbo]

EDIT: I think I may have figured it out. Is CN2 for buttons, CN3 for rotary encoders, CN5 for the MIDI, CN6 for USB? If that is the case, what do CN1 and CN 4 connect to?

Why did you have to figure it out if you have a schematic and:

3. Pinout of the pads connectors is the same as in MegaDrum Kits in viewtopic.php?f=3&t=1420

?

Thanks dmitri, I missed the PDF with pinouts. I though it was something else

I'm still getting used to larger schematics. To be perfectly honest I only had a lazy look at it. I might have to get my head around it before I go for the build. I got all the parts today so I'm proper keen to get involved!