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c0nsumer
Joined: Aug 23, 2006
Posts: 6
Location: Shelby Township, MI
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 Posted: Wed Aug 23, 2006 7:48 am Post subject:
PCBs / Kits for SK-1 MIDI Input |
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Hey everyone... I've been wanting to add a MIDI input to my SK-1 using the MaxMidi DIY - SK-1 MIDI Mod. However, PCBs for this haven't been available for a while.
I've gone ahead and laid out a new PCB for it and I'm going to be ordering the first run of them this week. I'm also debating selling these as kits so others can add MIDI input to their SK-1.
I'm curious, are any of you interested in purchasing one of these? The kit would include everything you need to add MIDI to your SK-1, including the PCB, CPU, ROM, wiring, etc.
Estimated cost (this is really off the top of my head at this point) is under US$50.
I'm just now beginning to document everything here, so please take a look if you are interested: http://www.nuxx.net/wiki/Casio_SK-1_MIDI_Mod
-Steve |
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gmeredith
Joined: Jun 28, 2006
Posts: 82
Location: Tasmania, Australia
Audio files: 1
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| Posted: Wed Aug 23, 2006 11:44 pm Post subject:
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This guy here already sells them as a kit - I've bought 2 of them already:
http://highlyliquid.com/kits/skm/
He also has a number of other MIDI boards for controlling devices. Maybe you can give him a bit of competition!!
Have a look at the Yahoo Casio SK forum:
http://launch.groups.yahoo.com/group/CasioSK/
In the FILES section on the site, I have posted up a MIDI THRU circuit that works in conjunction with the MIDI IN kit, to give you a MIDI in/thru conversion for the SK1, SK5 and SK8 (you'll need to join as a member in order to access the files).
Maybe you could build a combo MIDI IN/THRU board and sell it - you could probably make it smaller than the area of the individual boards, and save space. I have them both installed in my SK8, they work really well together.
Cheers, Graham |
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c0nsumer
Joined: Aug 23, 2006
Posts: 6
Location: Shelby Township, MI
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| Posted: Thu Aug 24, 2006 6:29 am Post subject:
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| gmeredith wrote: | This guy here already sells them as a kit - I've bought 2 of them already:
http://highlyliquid.com/kits/skm/
He also has a number of other MIDI boards for controlling devices. Maybe you can give him a bit of competition!!
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Huh, interesting. Thanks for showing that to me... It looks like he is using a PIC to handle things. I must say, if he's having those boards manufactured in at least 100 piece quantities there isn't more than $15 worth of parts or so in that kit.
Thanks for the pointer. I've submitted a membership request. For some reason I can't just join...
Hopefully people there will be interested in purchasing these. I'm really not sure how many I'm going to have manufactured, but I'll be sending them out today. probably 10 or 11 to start...
| Quote: | In the FILES section on the site, I have posted up a MIDI THRU circuit that works in conjunction with the MIDI IN kit, to give you a MIDI in/thru conversion for the SK1, SK5 and SK8 (you'll need to join as a member in order to access the files).
Maybe you could build a combo MIDI IN/THRU board and sell it - you could probably make it smaller than the area of the individual boards, and save space. I have them both installed in my SK8, they work really well together. |
That's an interesting idea, but unfortunately I'm out of space on the PCB. MIDI THRU is really easy to do, though. Just take the output of the optocoupler, throw it into a 220Ω resistor, and straight into Pin 5 of the MIDI THRU jack. That's it...
Maybe if I redo my own implementation with a PIC (similar to the one you linked to above) I'd consider it... Should be very easy then.
I haven't seen the schematic you were speaking of yet (silly membership approval requirement) but I presume it'd be pretty similar. You can see a how I did the MIDI THRU on the MIDIbox SID-NUXX I designed in the schematic here.
-Steve |
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gmeredith
Joined: Jun 28, 2006
Posts: 82
Location: Tasmania, Australia
Audio files: 1
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| Posted: Thu Aug 24, 2006 7:28 pm Post subject:
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The MIDI SID looks pretty good.
Which raises an interesting question: What would it take to give the Casio SK keyboards MIDI OUT?
You might say, "why would you bother, there are stacks of cheap MIDI keyboards already out there - why would you use a toy keyboard as a controller keyboard?"
well,
1. Just because it's possible (if it WAS possible)
2. An exercise in design
3. Kitch/wow factor - 80's toy keyboard blowing off professional keyboards
4. Good portable minimalist controller/sound module in toy circuitbent gigs (they are becoming increasingly popular)
5. Fantastic portable MIDI sketchpad songwriting tool!
6. Combined with the other mods being done on this keyboard, it becomes very useable
7. Unique sound (whether good or bad)
8. Casio SK circuitbending community building
9. You have to own one to understand points 1-8!!
and other reasons - anyone care to add to the list?
Since you've made a MIDI IN port, you would have some idea of the SK's hardware capabilities. Is it possible?
Cheers, Graham |
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c0nsumer
Joined: Aug 23, 2006
Posts: 6
Location: Shelby Township, MI
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| Posted: Thu Aug 24, 2006 8:08 pm Post subject:
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| gmeredith wrote: | | The MIDI SID looks pretty good. |
Thank you. I'm quite happy with it. I'm just waiting on the remaining metal panels for it so that I can finish assembling the three I'm building, and send the two off as piles of parts to friends.
| Quote: | | Since you've made a MIDI IN port, you would have some idea of the SK's hardware capabilities. Is it possible? |
Yes, wholly possible. You'd just have to watch the keyboard lines, read that matrix in to something which sends MIDI out, and have some method where the device won't feedback and trigger itself. I think that'd be the hardest part.
That said, with lack of velocity sensitivity, I personally wouldn't bother.
-Steve |
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gmeredith
Joined: Jun 28, 2006
Posts: 82
Location: Tasmania, Australia
Audio files: 1
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| Posted: Thu Aug 24, 2006 8:41 pm Post subject:
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I don't think lack of velocity would worry the SK community, they're used to having less things than that in the SK 
Besides, velocity can be overrated sometimes. Many of the early classic MIDI keyboards, such as the Juno 106, poly 800 etc. didn't have velocity, either. And people are still using them to do great things. Consider it. I'd buy a MIDI OUT board for my Casio SK8 from you!
Cheers, Graham |
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c0nsumer
Joined: Aug 23, 2006
Posts: 6
Location: Shelby Township, MI
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| Posted: Thu Aug 24, 2006 8:43 pm Post subject:
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| gmeredith wrote: | I don't think lack of velocity would worry the SK community, they're used to having less things than that in the SK
Besides, velocity can be overrated sometimes. Many of the early classic MIDI keyboards, such as the Juno 106, poly 800 etc. didn't have velocity, either. And people are still using them to do great things. Consider it. I'd buy a MIDI OUT board for my Casio SK8 from you!
Cheers, Graham |
Thank you.  If I get a chance and the drive to do it, I'll put such a thing together. It'd be easier to to just MIDI out... In and Out together will be the hard part.
But, I'll consider it.
Oh, and the PCBs are ordered if anyone is interested. With any luck I'll have 10 within two or three weeks.
-Steve |
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gmeredith
Joined: Jun 28, 2006
Posts: 82
Location: Tasmania, Australia
Audio files: 1
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| Posted: Fri Aug 25, 2006 1:21 am Post subject:
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Just an OUT board would be fine with me - and many others, who already have the IN board already fitted!
Cheers, Graham |
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c0nsumer
Joined: Aug 23, 2006
Posts: 6
Location: Shelby Township, MI
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| Posted: Fri Aug 25, 2006 4:42 am Post subject:
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| gmeredith wrote: | Just an OUT board would be fine with me - and many others, who already have the IN board already fitted!
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Graham,
I don't think you understand what I'm saying. An OUT board would connect to the same pins as the IN board, which is where the keyboard itself connects to the mainboard.
As such, with the setup you are describing, if you used a device to trigger a note on the SK-1 (using IN) it would also register as a note on OUT, potentially creating a loop. Some method of filtering this would have to be devised, or maybe just run them on separate channels. But that would be inelegant.
-Steve |
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bigtex
Joined: Mar 30, 2006
Posts: 323
Location: Cupertino, California
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| Posted: Sun Aug 27, 2006 6:21 pm Post subject:
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Oh, hey. Good to see you around here (robocowboy from LJ, here).
Am I correct in assuming this only triggers notes, and does not trip the sampling option or "press" any of the other buttons on the SK-1?
What would be really nice is to have, if nothing else, the sampling button be MIDI triggerable, and perhaps also the bend that turns off the drum sounds so there's no DINK sound when sampling is complete. Then I could completely automate all of the aspects I like to use when sampling. The other bends are fun, too, but they all start to sound the same eventually. But having every possible bend and button MIDI controllable would be AMAZING. That would require quite a few more parts, though. |
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c0nsumer
Joined: Aug 23, 2006
Posts: 6
Location: Shelby Township, MI
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| Posted: Sun Aug 27, 2006 6:24 pm Post subject:
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| bigtex wrote: | Oh, hey. Good to see you around here (robocowboy from LJ, here).
Am I correct in assuming this only triggers notes, and does not trip the sampling option or "press" any of the other buttons on the SK-1?
What would be really nice is to have, if nothing else, the sampling button be MIDI triggerable, and perhaps also the bend that turns off the drum sounds so there's no DINK sound when sampling is complete. Then I could completely automate all of the aspects I like to use when sampling. The other bends are fun, too, but they all start to sound the same eventually. But having every possible bend and button MIDI controllable would be AMAZING. That would require quite a few more parts, though. |
Hey there... I think that all of this, except for the stopping of the 'dink' sound, could be done with a custom MBHP device, or a PIC-based whatever. That 'dink' sound is likely internal to one of the ICs on there and would take some reengineering to get around.
-Steve |
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bigtex
Joined: Mar 30, 2006
Posts: 323
Location: Cupertino, California
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| Posted: Sun Aug 27, 2006 6:44 pm Post subject:
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| c0nsumer wrote: | | Hey there... I think that all of this, except for the stopping of the 'dink' sound, could be done with a custom MBHP device, or a PIC-based whatever. That 'dink' sound is likely internal to one of the ICs on there and would take some reengineering to get around. |
I don't have a diagram handy, but there's a bend that basically turns off all drum sounds. Including the dink. So it would be a matter of a pin going high and tripping a transistor or something to make the bend. Maybe a patch change message could enable/disable drums. That might be kinda cool.
It would be more effort, but even cooler to use maybe a MIDI CC driving 7 bits of a DAC to get a voltage to control the pitch bend as well as the drum volume bend. Then they could be controlled with some really nice precision. Perhaps excessive, but awesome as well.
Are there any microcontrollers with built-in DACs? I know most have ADCs, but I haven't used any yet with DACs. |
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gmeredith
Joined: Jun 28, 2006
Posts: 82
Location: Tasmania, Australia
Audio files: 1
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| Posted: Sun Aug 27, 2006 8:19 pm Post subject:
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Hi cOnsumer,
| Quote: | | As such, with the setup you are describing, if you used a device to trigger a note on the SK-1 (using IN) it would also register as a note on OUT, potentially creating a loop. |
I don't see the problem with that, really. ANY MIDI keyboard sending on the same channel as it's receive channnel will have this problem, if its MIDI out is connected back into its MIDI in, through a device, such as a sequencer, for example. I already get this with my Casio FZ-1 sampler and my sequencer. You simply either change the receive channel while your using it to control another keyboard or playing into the sequencer, or turn the volume off while your recording the other synth, or use the MIDI OUT/THRU merge facility on the sequencer. You could also make a simple MIDI mute switch on the MIDI in port. Lots of ways to overcome it. It honestly isn't a problem, that's what happens with all MIDI keyboards.
Cheers, Graham
| Quote: | or maybe just run them on separate channels. But that would be inelegant.
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No, not inelegant, that is how it is actually done. That is how I use my FZ-1 as a master keyboard.
Let me explain the scenario a bit more, with a diagram (see below):
The Casio SK MIDI IN Kit by "Highly Liquid" that I have installed in my SK8, and which you are basically making also, gives you the option of changing the MIDI receive channel.
If you now made a MIDI OUT board that you could also select the MIDI out channel, you could have the MIDI send set to channel 1, say.
Now, have the receive channel set to 1 (don't worry about the feedback issue - just follow my thoughts for a minute).
Look at the diagram below to see the setup you might use (this is the setup I presently use).
Firstly, set the Sequencer OUT/THRU MERGE to OFF (my MMT8 sequencer has a switchable port merge feature, as do many sequencers and software sequencers).
Start off recording the SK's notes on the sequencer on channel 1.
Play back the sequencer, to hear what you just recorded. The SK plays, but no feedback occurs, because the signal that comes out of the sequencer goes into the SK, then into the sequencer again, but does NOT come out of the sequencer's OUT port again, because the OUT/THRU merge on the sequencer is OFF.
Now, set the SK OUT to channel 2, and switch the Sequencer OUT/THRU merge to ON. Play the SK. You should hear the synth module play. You will also hear the SK, because you are playing its keys, if the volume is up, but you will not get feedback, because the SK is sending on a different channel than its receive channel.
Hit PLAY on the sequencer. You should hear the SK playing. Hit record on the sequencer. Record the synth module line on channel 2.
Hit Play. The SK AND the synth module will play on their own channels.
Do the same for the drums on channel 3. Play it back. All 3 should play. Now, the only time you'll get feedback is if you set the SK's SEND channel back to 1, and have the sequencer MIDI OUT/THRU merge switched ON. Any synth with an OUT and an IN will have this issue under those conditions. But then, all that you do is switch the OUT/THRU merge on the sequencer to OFF.
Like I said, this is how I already run my system, with my FZ-1 sampler in place of an SK. It gets MIDI feedback if you set the send and receive channel the same, and the sequencer OUT/THRU merge is ON. So it would not be a problem unique to your SK MIDI OUT board, if you built one. And certainly not an issue in my setup, especially if the MIDI OUT board had its own MIDI channel select.
Hope that made sense,
Cheers, Graham
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Last edited by gmeredith on Sun Aug 27, 2006 10:06 pm; edited 3 times in total |
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gmeredith
Joined: Jun 28, 2006
Posts: 82
Location: Tasmania, Australia
Audio files: 1
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| Posted: Sun Aug 27, 2006 8:23 pm Post subject:
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BigTex,
I don't know about the SK1, but my SK8 sample pads (4 of them) AND the drum sounds AND the keyboard can all be controlled by MIDI, all at once!! I suspect that the SK1 might be similar, because you can access all of those sounds when you record a sequence on the sk1, and all it would be doing would be triggering keyboard matrix/drum matrix line wires to do it.
Cheers, Graham |
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