If you want to connect your USB keyboard to your MIDI gear without a computer, this little box might fit the bill
Kenton MIDI USB Host review
USB Host To MIDI Converter Connectors: 1 x MIDI input / output, USB Dimensions: 110 x 55 x 32 mm 5V Power supply (included) 30 30-Day Money-Back
Kenton Midi USB Host
MIDI USB Host, MIDI interface, extension, power supply, in, out.
Kenton MIDI USB Host
Kenton MIDI USB Host
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