MegaDrum 56 inputs latest schematic and PCB

[Krisbo]

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

Thanks bud! Am I correct in that these aren't needed as programming can be done via USB?

[Johnfreeth]

I think you need the ICPC "cable" to program the PIC18F2550 before you can use the USB
See this link:
http://www.megadrum.info/content/programming-mcus

[jjpl2001]

First Thanks for all your job here..

I can see holes at the 4851 board, I was thinking that 4851's where only surface mounted chips, arent they, can you find the DIP16pin SOIC 4851's ? (socket mounted version?)

[Johnfreeth]

In the U.K. you can get them from Farnell. See this link
http://uk.farnell.com/jsp/search/browse ... allpartial

[mbira]

One little confusion for me-why does CN4 have 6 pins on the PCB, but the cable only used pins 3-6? Why not just have it be a 4 pin connector?

[dmitri]

One little confusion for me-why does CN4 have 6 pins on the PCB, but the cable only used pins 3-6? Why not just have it be a 4 pin connector?

To program it with a programmer which can provide power, e.g. PicKit2.

[mbira]

Cool! Funny enough, I just ordered a Pickit2 last night since I have had such troubles with my friends Serial port.

[jman 31]

Cool! Funny enough, I just ordered a Pickit2 last night since I have had such troubles with my friends Serial port.

Pickit2 is a great little programmer. I have had very good luck with mine.

[Necrotique]

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

a small question. what are the red lines in the components_small.png?

greetings

[dmitri]

a small question. what are the red lines in the components_small.png?

Wire jumps.