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Just a spoonfull of surly, snide, sarcastic condescension helps the bitter pill go down The bitter pill go down The bitter pill go down Just a few lines of rancor help the bitter pill go down In the most repulsive way...

Jidis and Synapsys, Thanks for the info. That helps a lot!

moebius, Is this really how a High Guru of the Midibox Priesthood should be behaving?

Years ago, I got one of the last E510 MIDI scanner kits that Maplin sold. I also have Craig Anderton and friends' book, "Digital Projects for Musicians." They both do some interesting things with the midi in/outs. As with the midibox, the midi in of the MidiTools computer (DPFM book) is opto-isolated with a 6N138. In the MidiTools computer, a midi thru line is then split off of the midi in. The signal goes through a 74HC04 hex inverter twice to buffer/invert/invert again the signal before reaching the midi thru jack. Does this also help to clean up the signal - sharpen the rising/falling edges? Does it help to isolate the signal? The E510 has no midi in. The midi out of the MidiTools computer and the E510 also are run through a 74HC04/74LS04 hex inverter twice to buffer/invert/invert again the signal. The E510 also splits off an extra midi out using the 74LS04. The signal is inverted, then split, then the two lines are seperately inverted again and sent to the connectors/jacks. Does anyone like this idea? This seems like a simple and elegant way to give yourself several midi outs in case you want to, for example, drive a sound module from a midified organ and also run a signal into a computer sequencer to record the performance. A very simple midi splitter module could be made to offer several identical buffered midi outs to drive different devices, either using the 74HC04 or and op amp voltage follower setup. Any thoughts? I hope I am getting the lingo correct.

On this site the midi out is not opto-isolated either: http://www.electronicsteacher.com/tutorial/midi-controller.php Anyone care to explain why?

Hi everyone, I was wondering why the midi out (tx pin) is not opto-isolated on the core module or the midi-merger with a 6N138, like the midi inputs are?

I have a question about the midi merger. How does the PIC17F87x read the three bytes coming in on the RX pin without risking missing data coming in on the RA4 pin?

Hello all, First of all, please excuse the length of this post. I am interested in building a velocity sensitive midi keyboard and a velocity sensitive pedal board. "Why build a velocity sensitive pedal board?," you may ask. Well, the main reason I want to use a pedal board is to play the B4, however there are some great synth basses and sampled basses that would sound great with velocity. I also think velocity sensitivity is an indispensable aspect of my musical expression. I am mainly a jazz pianist, who wants to learn how to play jazz B3 (B4). If I make a midi B3, I also want it to be a controller for the plethora of velocity sensitive sounds that are available. I am new to the midibox projects, but I have tried several times to adapt the processors of existing keyboard controllers to a custom keyboard I am building. I have designed and created several pcb's to house the scan matrixes and the SPDT spring switches that you often see in old keyboards. I even gold plated them so that they would not corrode. But up to now, I have not been able to get a dependable scan of the key motion. At the time of my last midification attempt, I knew very little about electronics; and the inner workings of the chips remained a mystery to me. Now with the Midibox OS and apps I am filled with hope. I know I can get this keyboard working just like I want, and also understand its inner workings. I have begun to study some books on PIC programming, with the goal of understanding every word of the MIOS, if that is possible without being a programmer for a living. I am excited to see where the documentation project goes, also. The main question I have currently is --- Is there any interest in putting velocity sensitivity in the MIOS? How hard would that be? Would it require an extra module to be created? I think it would be a great addition to an already awesome arsenal of applications. What does everyone think? I am not asking for free programming from the senior midibox programmers. I would like to contribute in any way I can, if there is a shared interest in adding this feature. Learning to write code is a goal of mine, but I am just getting started. This is probably an ambitious addition. I do know from the little I have tinkered, that the chip scans each SPDT switch, which is arranged in a diode matrix. When a key is depressed about a third of the way, the horizontal spring, which has been held up by the key, now releases from the top contact. Then after another third of the key travel, the bottom contact is closed against the spring. The chip times how long this took and generates a number from 0 to 127. If it took a short time a high velocity number is generated. If it took a long time a low velocity number is generated. A note off message or a zero velocity message is sent when the spring has released from the bottom contact and contacted the top contact. The standard distance that a piano key travels is around .390". It probably would take a lot of tinkering to come up with some velocity curves that would feel and sound good. On the switch boards I made, I worked out a way to make the upper and lower contacts out of brass rod, which I bent into little staple-like shapes and then had gold plated. I made a simple jig to help me solder them in place with a fairly even gap between them from key to key. After soldering them, I put a fillet of epoxy at their bases to ensure that they were stable. I could send some pics if people are interested. If this is not a feature that will be added any time soon, I would like to try to use the mkcv128 velocity sensitive keyboard MIDI encoder created by Jordan Petkov and sold at: http://www.geocities.com/midiboutique/. I would then like to midi merge it with a midibox project for all of the other control features. Does anyone have advice on how I would make this work? Would I just use a midi merge module to wire it into a core module? In the mean time, I am going to dive in and make some core modules, a jdm, a midi merge module, and a din module. I'll work out all the specifics as I go. Peace!

Thanks chriss and SmashTV for the comments. I am still forming a basic understanding of PIC programming with the computer (and electronics in general, and the command line.) I have ordered some PIC programming books, which are on the way. Although, I plan to start a project without the ability to burn PICs; eventually, I would like to write some code. So, I might as well begin tackling all the computer challenges, now. I am very new to this, so excuse me if I state the obvious or repeat myself. I have a lot of questions on how to proceed. What I need first is programs like IC-Prog, MPLAB IDE, and SDCC to write, read, compile, and burn code files. Correct? It seems that NOT ONE program for writing, compiling and burning code into a chip exists for the Mac! I searched the web for quite some time with no luck in finding anything. Bill really does have a nice monopoly going! Are there any programs that Midibox people are using on Linux? It looks like a lot of development is happening to get PIC programming on Linux - http://www.gnupic.org/. I would like to get a computer running Linux in the near future. A major goal of mine is to use the open-source Ardour digital recording software (http://ardour.org/) with a Midibox, if that is possible!! It would also be great to do all the PIC coding and burning in Linux. I would appreciate any advice on setting up Linux for MIOS. In the mean time, I would like to try to emulate the Windows environment on my Mac using open source software, rather than buy the Microsoft "Virtual PC on Mac" program. There is an open source project called Darwine, which is porting over the Wine (Wine Is Not an Emulator) project to OS X. I don't think wine is working under Mac's X11.app. Darwine looks very promising, but it is still in development. I wonder if that would work. I am concerned about all of the hardware and software working properly. I still think this might be a good approach, since people can use the software they are used to. With some help, I would like to try this. Is anybody else trying this already? Where does Perl fit into the Midibox programming settup. By the way I do not know how to read .php files in OS X. How does one do that? In the bootstrap page, Thorsten talks about a perl script to convert hex to syx. Where is that? Do you need to download it? Do I have this straight? When a PIC is first burned, it needs to use the JDM Module or now the Brocolli18. After that, any changes can be done through MIDI using the bootstrap loader and programs like MIDI-OX and (for Mac) SysEx Librarian. Correct? Is the bootstrap loader code that is written into the MIOS? Or is it hardware? The beginning description in the MIOS Bootstrap Loader section tells what it does - not what it is. I am not sure what it is. It would be nice if MIOS/PIC programming was worked out for the Mac OS X/Darwin/X11 and Linux platforms and then documented on the web site. I personally would like an alternative to needing Windows. Maybe some sections of the forum dedicated to getting different computer OS's operating with various hardware and software could be helpful to a lot of people. Let me know what you all think, if you wish. Thanks.

Hi everyone, I am very excited about building many of the Midibox projects. For starters I need some basic help with getting my computer set up. I have spent the last 3 weeks getting my Mac running X11, so that I may take advantage of Eagle and many other freeware programs that will be useful. I have downloaded a program called "pcb" and I am starting to learn my way around it. Has anyone else had experience with it? I am new to the command line and shell scripts. It is a lot to learn, but very interesting. I very much like the deeper understanding of how computers work. I have Eagle now running, but I can't figure out how to download the various .brd files off of the Midibox website and load them into the Eagle program. Can anyone help? Pdf files of the pcb's might be helpfull for people who want to do the copy-machine/toner/iron/etching process. Also, what setup do I need to get a PowerBook G4 laptop burning chips? I see what looks to me as a 15 pin serial port in the back. Is that what I use? Or, do I need to buy a device that converts USB to Serial Port? How are people setting up Macs to burn chips? Thanks for any advice. I am eager to dive in!!