Rock Band with Electronic Drums (HOWTO) - Page 4

Aelius27 · #31 01-09-2008, 03:40 PM

The MSA board looks like a really good solution.

To answer your question, for my LPT access I'm using the dll/driver described here: http://logix4u.net/Legacy_Ports/Para...000/NT/XP.html

Hope that helps!
-- Scot

zolon · #32 01-09-2008, 03:51 PM

Thanks Aelius27.

I actually was reading that page last night, and started working down that path when I stumbled across the MSA.

After talking with my roommate who is currently in school for programming, we both agreed a hardware solution would be better because we wouldn't have to worry about system overhead then.

I wouldn't have even thought about either solution with out your insight though, so again, thank you.

Blanko · #33 01-09-2008, 04:29 PM

Wow, amazing work Aelius and zolon.

Aelius, can I bother you to confirm the soldering tool I noted a few posts back is satisfactory? I'm also still a little un-clear as to how I'm to connect the opto-isolators to the parallel port - it sounds like I'd still need a breadboard (though no microcontroller).

Zolon,
Again - excellent solution. I'm still anxiously waiting on more details regarding the pc mod. But I'll happily jump on this project as well. (But I certainly don't want to steal you thunder.) But would you be able to post a rough plan of attack?

Also, are you having the board pre-built for you? I'll order one today - I'm just concerned I'm getting in way over my head.

D

zolon · #34 01-09-2008, 04:36 PM

If you have the funds, and don't know how to solder, get it pre-built.

Also, do yourself a favor. Go to radio shack or fry's or some other electronics store that sells parts, and pick up a hobby kit. Use it for practice on soldering. Make sure you get one that requires soldering.

Course, the MSA is cheap enough, you could just pick up a couple of them so you can practice. As most kits I am seeing are about the same price now.

http://www.aaroncake.net/electronics/solder.htm

That is just the first link on google when searching for "How to solder" .

There is ALOT of information out there.

When I have time tonight, if I have time, I will do a rouch sketch and scan it in of how I'm going to attack this with the MSA. I want to do that anyways so there are step by step instructions.

Aelius27 · #35 01-09-2008, 04:41 PM

I have one of those cold-heat soldering tools, and was very unimpressed. I much prefer my $10 cheapo soldering iron I got from radio shack.

Zolon: Yeah, the MPA solution looks like a good price. All of my solutions have focused primarily on what I had lying around, so were very cheap. As I mentioned in the inital post, figuring out where to wire the buttons and such is the springboard, once you get to that point there are a million different options for what is essentially a midi-to-switch solution. Opto-isolators, transistor switching, relays, etc.

I also prefer a hardware solution honestly, but wasn't 100% happy with the performance of the BasicX processor that I happened to have on hand, and the PC was an easy/free substitution. I'll certainly be moving to some kind of standalone hardware solution in the future.

Aelius27 · #36 01-09-2008, 04:55 PM

Looking at the MPA specifications, I don't think their products are going to work...

Their products only seem to support having the relay on for as long as the Note is on. The problem here is that electronic drum hardware generally sends the Note Off message immediately after the Note On message. So the relay (or whatever) will only be on for a few milliseconds. In my fairly extensive testing, I needed to hold the switch closed for ~ 35ms in order for there to be no dropped notes.

I believe the drum chip is using a polling method to get the button data, rather than reacting to the rise or the fall. So if you don't have the button "down" for ~ 35ms then sometimes the timing of the poll misses it entirely.

Additionally, it doesn't look like the MSA products support multiple midi notes going to the same relay, which is one of the best reasons to use an electronic drumset. Having 2 crashes & Tom3 all be the green trigger is _really_ nice.

zolon · #37 01-09-2008, 05:04 PM

Hmm.. Even when soldered directly to the buttons on the controller portion?

Only one way to find out, and if it doesn't work, then I could run the drums to my computer, and use Reason or something to send a longer note on. Then I am MIDI all the way to the controller.

I think there might be a way to program the MIDI Drum Kit Controller to also send a longer "Note: ON" signal. I will look into that when I get home.

And on the multiple triggers for one pad, I already thought about, with optoisolators or something, of joining the output pins on the MSA for multiple channels.

Aka, say HighHat is Channel 2, and Tom1 is Channel 3. I would solder the output pins for both channels to Yellow on the controller.

I just emailed Highly Liquid and asked if there was a way to add delay between the Note ON/OFF signals using the MSA.

If not, and still wanting to stick with a complete hardware solution, I could use something like this.

http://www.maplin.co.uk/module.aspx?...24&doy=9m1#faq

Not that exactly, but I am sure there is something closer to what I am looking for out there.

Aelius27 · #38 01-09-2008, 05:13 PM

Okay, here is a snapshot of where I wired by signals in. I did this because I wanted the controller section of the drums to remain functional as a controller. You can kind of see in the picture that I wired my signals to a DB-9 connector to make transportation easier.

I would highly recommend you keep it functional as a controller, since you can't navigate in any of the standard xbox menus (profile/sign in/etc) using the drumset.

http://home.comcast.net/~Aelius27/DSCF0029.JPG

The wires are sort of color coded. Green is on the top, last pin on the right. Red is on the right, 5th pin down, followed by blue (6th pin), then Yellow (7th pin). Finally the kick is on the bottom, 5th pin from the left (next to an unconnected pin).

I got ground from an unpopulated location below the USB connector, on the right side of the board.

Aelius27 · #39 01-09-2008, 05:15 PM

Zolon: Yes, even when soldered directly to the buttons. If you use a multi-meter, you'll find that the locations I soldered to are 0 Ohm resistance to the button pads. I chose those locations specifically because they were effectively identical to the button pads, but left the button pads functional.

Aelius27 · #40 01-09-2008, 05:20 PM

The R8 that Brian used supports all sorts of different programs, which is undoubtedly why it is 6x the cost of the MPA solutions. He was able to ignore the Note Off messages, and just program Note On messages to turn the relay on for 40ms. He was also able to program it to turn the same relay on from several different pads.

Let me know if they get back to you with any solutions though. For $50 I'd probably pick up one of the MPA solutions as well. Easier than rolling my own.