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MIDIbox-to-USB


Guest Rob

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Since there's a MIDIbox-to-COM Interface, would it be possible to create a MIDIbox-to-USB Interface too? Preferably something that could be used with an existing driver (like the Roland PC-300)

Is this possible or just way too complicated?

It would be really nice  for some applications to not have to worry about having a MIDI interface around. Maybe it could also help speed things up?

/Rob

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Hi All,

I just found (through another list) a USB Atmel programmer at http://norum.homeunix.net/%7Ecarl/atmel/ with hardware and software stuff. I have not had a chance to look it over yet, but maybe some of the information could help adding USB to our projects. The USBLIB is the part that we may be able to use. It's a cross-platform USB Library.

Later,

Mickey

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Thanks for pointing me to the older posts. I just discovered MBHP a couple of weeks ago and is still digesting info about this neat project. :)

For those of you that wants a refresher of what Thorsten said about USB back in August, here's a snippet:

the hardware & firmware implementation of a MIDI USB device is pretty simple, the USB controller has to send the specified descriptors which are documented in the USB MIDI specification (see www.usb.org) and have to manage the MIDI In/Out Streams on the same way like the MIDIfilter/processor, and voila - Windows (ME, 2000, XP), Mac OS X, Linux will open a MIDI In/Out device immediately without an additional driver!  

But there is a big problem which prevents me from offering such a device, and thats the availability of an USB microcontroller which:

* is flash-programmable

* is worldwide available in low quantities (for hobbyists)

* comes in a DIP packages (most USB chips are SMD)

* doesn't require an expensive development board

The fact that it doesn't need a driver makes it even more appealing. It hope that a solution will appear eventually that makes it possible for Thorsten to add this functionality to the MBHP. That would make a great project even greater. :)

/Rob

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Hi Mickey,

this library  is dedicated for USB hosts, USB clients don't need such a complex library. For clients, the most stuff is already implemented in the hardware, so that the software nothing more has to do than to react on requests which have been initiated by the host.

The Atmel programmer uses a Cypress chip (btw.: the same chip can be found in MIDIman USB interfaces.. ;-)) - it"s a SMD chip... :-/

Best Regards, Thorsten.

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  • 2 weeks later...
Only $2.65US too !!!

In thousand plus quantity, and it is at it's "end of life" (notice the "[Not recommended for new designs]" statement at the top of the page)

Designing with EOL chips scares me!  

:)

Check out: http://www.dlpdesign.com/usb/usb232.html

It's $25 in single quantity, but it would be much easier to implement (Thorsten would not have to code around it), comes on a standard DIP carrier (not surface mount) and it has royalty free drivers for PC Mac and UNIX.  You can practically throw this at any design that already uses RS232 to communicate.

I know it's not the low cost solution everyone is looking for, but it would be easy to implement.

The easiest USB solution so far has been using the Keyspan adapter, and some (not Midiboxers) are writing thier own firmware for those to customize to thier need. See http://people.omnigroup.com/wiml/soft/pic/keyspan.html for info on "repurposing" these interesting little things.

Later all!

SmashTV

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Guest neuronet
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COOL!

An USB controller in a handy DIP package with IIC interface (the same protocol which is used by the BankStick)

Maybe this is the solution - especially because MIOS already supports IIC. It is possible to connect multiple IIC devices in parallel!

MIOS_USB_* :D

Best Regards, Thorsten.

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Woohoo... Exciting news. :D

Be sure to keep us posted on this Thorsten. I'm still in the planning stages for my box and I would love to make a USB version that I could hook up directly to my Mac.

I'm going to make a controller for Traktor so it will need to be as portable as possible, so if I can skip the MIDI interface that would be great.

/Rob

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In the meantime I noticed that the DIP version of this chip has been discontinued. It seems also that the availability is not so good as expected (see the http://www.findchips.com results). But at the Beyond Logic page a short introduction about an upcoming PIC18F device with integrated USB support can be found - well, this will be the solution! :)

The USB interface allocates some pins which are used by the core module for other functions, but at least a "MBHP USB" module just only for the data transfer (and maybe also as reduced MIDIbox core) could be created. Estimated price: about 15 Euros! :)

Now we only have to wait for the release of the PIC18F2450 . There is already a firmware available for this derivative, which can be extended for MIDI transfer very easily!

Best Regards, Thorsten.

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But at the Beyond Logic page a short introduction about an upcoming PIC18F device with integrated USB support can be found - well, this will be the solution! :)

The USB interface allocates some pins which are used by the core module for other functions, but at least a "MBHP USB" module just only for the data transfer (and maybe also as reduced MIDIbox core) could be created. Estimated price: about 15 Euros! :)

Now we only have to wait for the release of the PIC18F2450 . There is already a firmware available for this derivative, which can be extended for MIDI transfer very easily!

This solution sounds even better (and easier to implement) :)

Do you have any idea when these new USB compatible chips will appear? There's a FAQ on Microchip's site about these "future devices" but it was written 2 years ago!

Discussion: Microchip's current devices (PIC16C745 and PIC16C765) support the low speed USB specification. The PIC18F2450, PIC18F2550, PIC18F4450 PIC18F4550 are future devices that will support full speed USB.

Does this mean we might have to wait a looooong time for these? :-P

Also, if one would create a "reduced core" with the USB functionality (instead of a new module), what current functionality would you lose out on?

A slightly less capable core, but with USB functionality might be more convienient for some applications compared to creating a new module.

Thanks!

/Rob

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Oh and BTW: If the Midibox could be USB enabled, would it be possible to use the USB supplied power to run it? USB supplies 5V, right?

Or does the Midibox consume more power than USB can supply?

It would be great if this could eliminate the need for an external power supply. It would make things extremely portable. Just a laptop and the midibox to carry around! No MIDI interface or power supply. :))

/Rob

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I'm not sure, the new derivatives could be released in some weeks, or in some months... however, I'm not under time pressure ;-)

Also, if one would create a "reduced core" with the USB functionality (instead of a new module), what current functionality would you lose out on?

There will be several pinouts available, one with a small number of pins, and other chips in a 40 pin DIP package like the PIC18F452. But unfortunately 3 pins are allocated by the USB interface itself (the pins which are currently used to serve the DIN/DOUT modules), so that I would prefer the first solution: a small, simple & cheap USB module --- all other solutions would increase my support and documentation effort a lot...

Best Regards, Thorsten.

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I would prefer the first solution: a small, simple & cheap USB module --- all other solutions would increase my support and documentation effort a lot...

OK, thanks for letting us know! :) Now we just have to wait for Microchip to get their act together and release those chips. lol

/Rob

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