Yes, very ghetto mod there.
I got an Atmega32L with 16MHz xtal. Anyway, I got the device working (at least the LCD says so) sans piezo testing. Then I tried programming the soic PIC18F2550 with winpic using the ICSP programmer detailed in the schematics page. But I got programming error below:
Info: Loading definitions for "PIC18F2550" from C:\Program Files (x86)\WinPic\devices.ini .
Info: Support for some newer PIC18F devices added by Martin v.d. Werff 2005
Couldn't find "devices\PIC18F2550.dev", please borrow/copy from MPLAB !
PIC18F: family='21'=4550, WriteLatch=32 bytes, EraseLatch=64 bytes .
Initialising PIC-Programmer: Success.
Testing: delay(500ms) took 0.50 seconds, timer_freq=3.9074 MHz ... ok
PIC- SelectVddNorm failed
Initialising PIC-Programmer: Success.
Initialising PIC-Programmer: Success.
Programming...
Erasing ("bulk" or "chip") ...
Programming CODE, 0x000000..0x001BE4
Verifying CODE, 0x000000..0x001BE4
Verifying 0x000000..0x001BE4
Verify Error: 000000: read 00FFFF, wanted 00EFE0, mask 00FFFF ==> diff=00101F
Verify Error: 000002: read 00FFFF, wanted 00F00D, mask 00FFFF ==> diff=000FF2
Verify Error: 000004: read 00FFFF, wanted 000012, mask 00FFFF ==> diff=00FFED
Verify Error: 000006: read 00FFFF, wanted 000012, mask 00FFFF ==> diff=00FFED
More Verify Errors, unable to list all (total=3571)
Programming CONFIG, 0x300000..0x30000C
Verifying CONFIG, 0x300000..0x30000C
Verifying 0x300000..0x30000C
Verify Error: 300000: read 00FFFF, wanted 000E22, mask 00FFFF ==> diff=00F1DD
Verify Error: 300002: read 00FFFF, wanted 001E3F, mask 00FFFF ==> diff=00E1C0
Verify Error: 300004: read 00FFFF, wanted 0081FF, mask 00FFFF ==> diff=007E00
Verify Error: 300006: read 00FFFF, wanted 00FF85, mask 00FFFF ==> diff=00007A
More Verify Errors, unable to list all (total=7)
ERROR: Programming FAILED !
I got two machines XP and Windows 7 detecting "Megadrum USB Midi" but cannot find and install drivers. Is this normal or should it installed generic drivers for the MD?
Anyway, I used my DMM and got the following readings from PIC18F2550 pins:
pin 1: 4.97v
pin 8: 0.00v
pin 14: 3.33v
pin 19: 0.00v
pin 20: 4.97v
pin 26: 0.06v (connected to 47k resistor)
These are the settings in winpic: