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OB-6 and Yamaha MD-BT01 bluetooth compatibility ?

OB-6 and Yamaha MD-BT01 bluetooth compatibility ?
« on: June 02, 2017, 06:20:18 AM »
Just cant get this bluetooth midi dongle to power off the OB-6. It powers off every other bit of Midi equipment I own, even my Bass Station 2 when under USB power, but for some reason not off the OB-6.

The dongle takes its power from the little voltage Midi needs to supply bluetooth midi data from IOS and Mac devices with BT4.
I have switched all data in the global menus from USB to Midi but still no power to the dongle, it cant take much bc, as I say, even the BS2 over USB can power it.

Any ideas whats different about the Obeys midi i/o ?

chysn

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Re: OB-6 and Yamaha MD-BT01 bluetooth compatibility ?
« Reply #1 on: June 02, 2017, 06:59:33 PM »
Of the 5 pins in a MIDI DIN, 3 of them are used for MIDI Out and Thru. The center pin is Ground, one pin is the UART for transmitting and receiving data, and the last pin is a +5V current.

DSI instruments don't provide the +5V current, so they won't power MIDI-powered devices.

Why would the Father Of MIDI not follow the MIDI specification to the letter? I've wondered that for years. Hopefully the device manufacturer provided an alternate means to power the thing.

My Little Phatty doesn't provide +5V, either, so it's not that uncommon. My guess (and now we're in speculation territory) is that the center pin isn't connected to Ground like it should be for the MIDI Out...?
« Last Edit: June 02, 2017, 07:03:59 PM by chysn »
DSI: DSM03; previously: Mopho Keyboard, Desktop Mopho, Evolver, DSM01
Hardware: Eurorack, Moog Little Phatty w/ CV Outs, Arturia MicroBrute, KMI QuNexus
Software: macOS, Ableton, MuseScore
Modular Grid: https://www.modulargrid.net/e/racks/view/354385
GitHub: https://github.com/chysn

Re: OB-6 and Yamaha MD-BT01 bluetooth compatibility ?
« Reply #2 on: June 04, 2017, 06:17:32 PM »
A $ solution could be to use a powered midi thru or merge from the midi out of the OB6.
http://www.kentonuk.com/products/items/utilities/m-merge4.shtml
http://www.kentonuk.com/products/items/utilities/m-thru-5.shtml

Seems gear with a midi out to drive an external device is hit and miss.

My DSI Tempest/P08/Mopho and Novation Impulse do not power external midi devices but the older Korg gear can.

Just as an example here is a list from Midi solutions products in the FAQ section that can give an idea of what is out there that can not provide the midi power for external devices.
http://www.midisolutions.com/faqs.htm

Good luck.



Tim

Re: OB-6 and Yamaha MD-BT01 bluetooth compatibility ?
« Reply #3 on: June 29, 2017, 06:36:00 AM »
Why would the Father Of MIDI not follow the MIDI specification to the letter?

I think because the MIDI specification do not include sending power to devices; the +5 connection is not a direct +5 connection for power use; the data connection is a 5mA current loop, and it is supposed to be opto-isolated, not to provide power to the receiving equipment.
Then, products that draw power from a MIDI cable probably make assumptions on the electronic implementation of the protocol, that may be do not corresponds to the OB-6 internals ...

Maurizio