MIDI controllers and synthesizers are connected using cables that allow the commands to be sent between devices using an asynchronous serial interface.

MIDI控制器与合成器通过电线相连接，利用异步串行接口可以在不同设备间传送命令。

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The idea was that children could use special Lego components to build their own experimental instruments, which would work as MIDI controllers.

ENGADGET: Music Thing: Musical instruments made of Lego

These two continuous controllers now need some code to grab their data and send it over MIDI.

ENGADGET: How-To Control Csound with a Custom Midi Controller: Hardware (2 of 2)