nebula

I have decided not to finish the single 4-SID PCB I had started laying out. Thanks for all your help anyway Thorsten, and the answers are still very insightful. Instead I think I will simply etch all of the layouts required on to one big PCB and just connect them that way. My reasoning? Well, I decided that if I start to change things around too much then I risk losing long-term compatibility with future advancements to the project / platform. For example Thorsten's new suggested power supply wiring seems very solid, and if I had created the big board such a modification would be very inconvenient. Also Thorsten recently made mention of possible panning using a forthcoming "AOUT" module, and my design may have omitted a port to plug such a module in on. I was initially worried that 4 cores and 4 SID modules would be an unmanageably large set of boards, but as has been demonstrated, with a little coaxing they will fit into a C64 case. So there really is no need to try to reduce the component count or increase the efficiency of the layout. I do have one other little tidbit of info though: my work uses a PCB layout program called "Protel 99SE", which I decided I would try to learn for this little project. I don't know what other PCB/schematic software is like for Windoze, but I have decided (based on my weekend's experience) that Protel ranks pretty high on the stink-o-meter. Part of my decision to stop working on the board is based on about 10 hours of frustration working with this crappy pcb software. (FWIW it seems powerful but has a ridiculous user interface)

:o :o :o That looks friggin' amazing. That is MIDIbox of the week for sure ;)

Very sorry. My parts list is for the MIDIbox Plus/16. My mistake. :-[

Was wondering if anybody had considered creating a MIDIbox, or perhaps a MIOS app, that would function like a Doepfer SCHALTWERK. This is essentially like a MB64 sequencer, but instead of pots uses individual button/LED combos, for creating percussion sequences. Allow me to dream for a moment... Wouldn't it be cool if you could build an MB64SEQ and include, say, 4 or 8 rows of such buttons, so that on one surface you could create crazy tweaky melodies at the same time as a drum pattern. Anyway - I just thought I'd share. (BTW if you're not familiar with SCHALTWERK go to www.doepfer.com and click "Products" and find it in the "sequencers" section.)

Hi Iain, I have created a Digi-Key Parts list for most of the 16E. It's an excel spreadsheet. Get rid of "no junk" from my email address reverbno@junkrogers.com and drop me a line, I will email you the spreadsheet. Note that I have decided to get some of the parts from other sources -- mostly sockets and switches and the like. BTW I have received some sample pots, digi-key p/n P3C3103-ND and I think they will be really awesome, not to mention cheap, for building any knob-box with board-mounted pots. I haven't actually used them yet but I think they're just what the doctor ordered. My friend and I will be starting to build our 16E's together probably early next month.

Hi Thorsten, thanks for accepting my suggestion on the 4 SID buttons! I hope to be able to offer more positive contributions in the future. This forum is just fantastic. How much does it cost to order a one-off panel such as that from Schaeffer Apparatebau?

My main computer is an older sawtooth G4 running OS 9 and OS X -- my main music app is Logic, and I'm learning to enjoy it under OS X, and find it remarkably stable. My other computer is an iBook 500 which primarily stays in OS X. I do use VPC for some things, and find that my good ol' version 4 runs Win 98SE quite acceptably under OS 9 on my G4.

Thanks Thorsten, I would never expect you to port the old stuff. I ask only because my friend has already etched a couple of boards for MB 16, and we already have most of the parts kicking around. We'll build the MB 16's using the older PIC, but I'm already started on designing a quad-SID layout :) Cheers, Nebula (Steve from Toronto)

Is it possible to use an 18F PIC in a MIDIbox Plus/16? My friend and I plan to make a weekend project of building a couple of MIDIbox plus, and I would rather do a quantity buy of 18F PICs for future projects than buy only 2 16F PICs at 3 times the cost. Has anybody tried this? Many thanks in advance.

For past projects I have custom-etched PC boards for pots, switches and LEDs and the results have always been good. Internally, it makes for a really professional looking project. Even though you may spend a lot of time designing the board (refer to the thread about the simple laser print method of transferring resist to circuit boards in the 'tips and tricks forum'), I like to do it because it makes it a lot easier to do mods to your project down the road, because your case is not full of spaghetti getting in your way everywhere. The other nice thing is that if you make a slight drilling error on your front panel it will be invisible, because the knobs will cover it up! The disadvantage is that your finished project will probably be a little less rugged. When I eventually get around to building an 8x16 rotary MB64 I will probably put the pots on the same board as the AIN module, that way the entire front panel can be linked back to the core with just a small ribbon.

Thanks Thorsten. I will get started on this, and of course once I have something that looks do-able I will of course share it with everyone! ;D Another question, and a suggestion: I am very anxious to see Step D: the complete surface. Am I correct in assuming that this will all interface with the master core module, and will not require another PIC? I suppose that type of thing is where the extra horsepower of the 18F shines :) The suggestion: I was looking at the front panel you have created, and noticed that there is a "select button" that lets the user decide which of the 4 SIDs they will be remotely controlling. While this is great, will the control surface have the ability to control multiple SIDs with one knob turn? For example, what if I set the unit up with a monster layered patch, and then wanted to adjust the filter in real-time on all 4 SIDs. Could that be done? I wonder if it might make sense to, instead of having one button to select SID # 1-4 sequentially, to have four separate buttons, each of which toggles whether you are controlling that respective SID. So you could press 1 and 2 (toggling them both to "on) and then be controlling both at the same time; then later you could press 2 again (toggling SID 2 to "off") and your controller is left to only control SID 1. I realize this might be somewhat more complex in software, however could probably make for some really great ways to use the unit live.

Using this method it's really hard to do boards as fine as the MBHP boards, which often have traces running between IC pins. What happens is that the toner tends to spread a bit when you apply pressure from the iron. It makes the tracks just a little bit wider -- enough to cause problems. Also watch for little pinholes, you really do need to dab with a permanent marker prior to etching. I use this method a lot, however, and have generally had very good results, but I'm re-laying out some boards so that I can continue to use this method to make some MBHP stuff.

I'm anxious to start building this, however I would really like to put the 4 cores and 4 sids on to 1 board. I think I should be able to minimize redundant parts in this way, i.e.: Only 1 each of 5V and 12V regulator should be required, Should be able to take the 1 MHz clock from one core module and split it between all 4 SIDs, eliminating 4 x 1 MHz oscillators, Only 1 opto would be required for the MIDI in, Only 1 rectifier and one set of filter caps required for the entire power supply section, Chance to omit all of the SIP and ribbon connections, as well as to leave alone many of the unused PIC pins for this application, saving board space, Keep the audio mixing section for all of the SIDs on one circuit board. I'm hoping to be a little ambitious and create a PCB layout that will put all of this stuff together, and be easy to etch by not including tracks that run between IC pins (i.e. no less than 1/10 inch spacing). Thorsten, can you tell me if there are any unexpected "gotchas" I can expect to run into? What worries me most, I think, is whether I will be able to input MIDI to 4 PICs using just one opto, and whether I can split up the core's 1 MHz clock output without causing excess loading. Would there be any advantage to using the same clock on all the SIDs, like phase coherence or anything? Also do you have any other suggestions about stuff I could eliminate by putting this all together?