How to Build/Setup a microDrum
Note: Thanks go out to WesleyS for putting together the original instructions from which this wiki post is taken. The original post can be found here: http://microdrum.altervista.org/forum/viewtopic.php?f=18&t=215%7CWesley%27s
These instructions are primarily for breadboarding the microDrum system for people that aren't ready to jump straight to the PCB version.
Most of the parts to make this I already had available to me, so the I didn't have too buy too many things. If this is all new to you and you need to buy everything, keep in mind that the same money spent on all these materials could buy you the official Microdrum PCB, the parts kit, and multiplexers(all from the Store), but the piezos would still need to be purchased. It would save you money to go ahead and buy the official parts, but if you would rather do this, by all means go ahead :)
 Step 1: Gather all components.
(Nearly all things can be bought from a local Radioshack instead of online.)
A LED is optional
For soldering leads to the piezos use a soldering iron and smaller gauge solder (20-24). I got those from Radioshack.
- NOTE* The quanties of parts are just for this build. If you would like to buy the maximum number of each parts so you don't have to do it later
(or if you don't want to buy the PCB/kit), get (6) 1 Meg Ohm Resistors, (6) Multiplexers, and (up to 48) piezo buzzers.
 Step 2: Downloads
The MicroDRUM ConfigTool v1.0: http://microdrum.altervista.org/blog/downloads/microDRUM_ConfigTool_v1.0.zip
MicroDRUM Firmware v1.0: http://microdrum.altervista.org/blog/downloads/microDRUM_Firmware_v1.0.zip
The Official Arduino IDE (or just the drivers if you know how to install them): http://arduino.cc/en/Main/Software
The MicroDRUM schematic I follow: http://s1281.photobucket.com/user/magicisdeadws/media/MicroDRUM/md24v12_zpsc1e107b5.png.html
 Step 3: Setting up the environment.
- Install the Arduino IDE first. Just run the .exe file(wndows) and follow the on screen prompts.
- Now plug the Arduino up to the computer. The drivers should have been installed when the IDE was set up. If not, just manually update the driver.
- To make sure the board is working correctly we're going to upload an example sketch to the board Called blink. It simply makes an onboard LED blink every second.
- To do this:
- Open the Arduino application
- Go to File > Examples > 01.Basics > Blink and click on it.
- Then go to Tools > Board and select your board (Arduino Uno).
- Next, select your Serial Port.
- Go to Tools > Serial Port and there should only be one option. Make sure it is checked.
- Also, write down what COM# it is(COM 3, COM5, or similar)
- Finally, upload the program.
- Underneath the File/Edit options there are two circles, one with a checkmark and one with an arrow pointing to the right.
- Click the one with the arrow pointing to the right. In the bottom right of the window you will see a progress bar. Once it says "done uploading", a small LED labeled "L" on the right hand side of the board will be blinking.
- If it is everything is working and we can move to the MicroDrum program.
If you need pictures or additional instructions for what was done above, go to http://arduino.cc/en/guide/windows
 Step 4: Uploading the MicroDrum Firmware
- Make sure your Arduino is still connected.
- Extract the "microDRUM_ConfigTool_v1.0.zip" and "microDRUM_Firmware_v1.0.zip".
- Run the "microDrum.exe" file.
- Under the Setup tab click the "Select COM" option. From the dropdown menu underneath the "Select COM" option select the same COM as serial port you selected in the Arduino IDE(the number you wrote down). http://s1281.photobucket.com/user/magicisdeadws/media/MicroDRUM%20construction/20140212_153433_zpsa9f770f5.jpg.html
- Now under the Setup tab select "Update Firmware". A new window will pop up. Select the "Uno" in the Box labeled Arduino. Then select your COM port.
- At the top there is an empty box that says "Firmware" to the left of it. To the right of the box there is a small box with three periods in it.
- Click that button and navigate to where you extracted the "microDRUM_Firmware_v1.0" folder and chose the "microDRUM_Firmware_v1.0.mhd" file. http://s1281.photobucket.com/user/magicisdeadws/media/MicroDRUM%20construction/20140212_154215_zpsd5126279.jpg.html
- Now click "Update".
- The box below the update button will give you some information. At the bottom it will either say the upload was a success or it failed.
- If it was a success, skip to step 5, if not follow along below:
- Go to: http://russemotto.com/xloader/XLoader.zip
- Exract the zip and run "XLoader.exe"
- Go to your "microDRUM_Firmware_v1.0.mhd" file and rename it to "microDRUM_Firmware_v1.0.hex"
- On XLoader click the "..." botton and select to your recelently renamed "microDRUM_Firmware_v1.0.hex" Select your COM# and Uno(ATmega328) in the dropdown menu.
- Make sure the Baud Rate is at 115200, then click upload. http://s1281.photobucket.com/user/magicisdeadws/media/MicroDRUM%20construction/20140212_160506_zpsb1a27b87.jpg.html
- It will say done and you have now uploaded the firmware.
 Step 5: Construction
Now we're going to assemble the parts.
- Go ahead and unplug the Arduino for now.
- Take the solderless breadboard and insert the multiplexer with the little "u" at the top.
- Use some of the 22 gauge wire and connect the top right pin to the + on the breadboard.
- Then use wire to connect the positive and negatives on both sides of the breadboard.
- Now connect the three pins on the bottom left of the multiplexer to the - column.
- Get a 1 Meg Ohm resistor and put it on the bottom of the breadboard with one end one the breadboard and the other on the - column.
- Now get a jumper wire and connect it to the multiplexer. Put it on the third pin on the left side and connect the other side to the resistor.
- Use another jumper to connect the other end of the resistor to the Analog 0 In on the Arduino.
- Take the 120 Ohm resistor and put one end on the breadboard and the other end on the + column.
- Use a jumper to connect the other end of the resistor to the "Reset" on the Arduino.
- Take a jumper and connect it to the pin on the botton right side of the multiplexer. The other end of the jumper goes to the Digital In 4 on the Arduino.
- Use another jumper and put it on the pin above the previous on, and connect it to Digital Pin 3.
- Take a final jumper and put it on the pin above that one, the third from the bottom on the right side of the multiplexer. Then connect it to Digital Pin 2 on the Arduino.
- Now take a jumper and put it in the + column. Connect the other end to the 5v on the Arduino.
- Use another jumper to connect the - column to Gnd on the Arduino.
 Step 6: Construction continued
All of the remaining open pins on the miltiplexer can be used as inputs.
- If you plug the Arduino into the computer and go to the monitor tab you will see that signals are being shown even though nothing is triggering it.
- To get that to stop use wire to ground all of the open pins but one. I left the top left pin open.
- Now get the piezo, solder, wire, and the soldering iron.
- Solder a piece of wire to the white part of the piezo and another to the brass ring.
- Strip about half an inch of wire on the end not connected to the piezo.
- The wire that is soldered to the brass ring goes to the - column and the other goes to the open multiplexer pin.
That's it for construction and set-up! now you need to configure each piezo for sensitivity and sound. I'll get into that later though. If you have any questions feel free to ask and I'll do my best to help out.