Open LS9 Control is a C++ library for controlling the Yamaha LS9 mixer. There are also Python bindings included known as PyOpenLS9.

It depends on the Network-MIDI driver for macOS or the Network Driver for Windows and the port name is "<Device Name> Port 1" where <Device Name> is the name from System Preferences.

A parameter is defined by an element, index and channel, defined in C++ as an aggregate thus:

struct Parameter {
  int element;
  int index;
  int channel;
};

And in Python as a dataclass thus:

@dataclass
class Parameter:
  "Some parameter of the desk"
  element : int
  index : int
  channel : int

In C++ the LS9 class is constructed with the port name as a std::string_view and exposes the following methods:

• static auto portNames() -> std::vector<std::string>
• void addGlobalCallback(std::function<void(Parameter, int32_t)> callback)
• void addParamCallback(Parameter param, std::function<void(Parameter, int32_t)> callback)
• auto get(Parameter param, std::chrono::milliseconds timeout) -> int32_t
• void set(Parameter param, int32_t value)
• void fade(Parameter param, int32_t value, std::chrono::milliseconds duration, std::chrono::milliseconds timeout)
• auto nextParamTouched() -> Parameter
• auto getChannelName(int ch, std::chrono::milliseconds timeout) -> std::string

The Python class is much the same: any callable can be used where a std::function is expected and an integer number of milliseconds is used where a std::chrono::milliseconds is expected. It also has the portNames static method which returns a list of strings.