Glossary of Terms:
 
To Host switch
Most commonly referred to as Host Select switch — a switch found on MIDI devices that have a To Host port, which selects the mode for Macintosh or PC. When using a Macintosh computer, the Host Select switch on the MIDI device must be set to Mac; when using a PC, the Host Select switch on the MIDI device must be set to PC2.
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Related terms:
  Firewire   MIDI   To Host cable   To Host port   USB   serial port   serial port cable   serial port driver