My Megadrum keeps connecting/disconnecting

[kimouette]

I tried 2 different USB cables on 2 different computers and tried all 6 USB inputs on my computers, my MD keep getting disconnected and reconnected. I also keep hearing the sound telling that I have plugged and unplugged a device, and device manager keeps refreshing like I was physically adding-removing a device from my computer.

What can I do?

[dmitri]

viewtopic.php?f=3&t=268

Is pin 26 of PIC18f25550 pulled to +5 or to ground over 22k-47k resistor if at all?

[kimouette]

I have respected the schematic for my specific kit (syntex v.2.7 kit)
It doesn't seem like pin 26 is going anywhere except to its ICSP connector that i dont even have

syntex2.7.jpg

Complete schematic is right here:

MegaDrum32 Synthex Schematics v2.7.gif.zip

I read that I should solder a 22k to 47k resistor between pin 3 and pin 6 on the ICSP 18F2550 connector. But geez, I dont even use the connector. I just have these 6 "pins" (the socket) hanging on the board. So I dont know where the resistor is physically gonna stand.
http://picasaweb.google.com/Kim.Tanguay ... 2276185426

And what about the firmware you added in my PIC18F2550? Do I have to change it or is it ok to keep the same one after I add the resistor?

Feeling noob again... how i missed that feeling

[dmitri]

Just add the pull down resistor, that's it.

[kimouette]

Do you think it's gonna be ok if i use alligator clips to clip the resistance on the 2 pins?
Otherwise I'm screwed! How the hell am I supposed to solder a resistance without blocking the pins that would be necessary if I ever need to plug a connector on the ISCP 18F2550?

[dmitri]

Solder it underneath.

[kimouette]

It's alive!!!!


Thanks Dmitri!
I soldered a 33k resistor between pin 3 and 6 of the ISCP 18F2550 (underneath the board) and for now everything seems to work like a charm!

[timekeeper]

Could this problem appear out of the blue in a previously working unit? Cause that's what happening to me right now...

[dmitri]

Could this problem appear out of the blue in a previously working unit? Cause that's what happening to me right now...

It could if you're using the Synthex's old firmware and the board.

[timekeeper]

Could this problem appear out of the blue in a previously working unit? Cause that's what happening to me right now...

It could if you're using the Synthex's old firmware and the board.

I am using Synthex's v2.5 PCB and your latest firmware.

I used a 4.7k resistor I had available and it works... Strange...