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Signal Flow

The driving of the device is managed by a group of systems collectively referred to as Signal Flow. Most of the systems are grouped into stages, with the idea that exactly one system is active in a particular stage at a given time, with values originating in the first stage, called the "Input stage", and then being passed forward by each stage to a following stage, until they end up in the final, "Output stage".

There are 5 signal flow stages:

1. Input Stage, which generates the propagated value.
2. Input Conditioning Stage, which can apply a transformation to the input.
3. Control Stage, which defines how the output is controlled.
4. Output Conditioning Stage, which can apply a transformation to the control stage output.
5. Output Stage, which finally sends the propagated value to the actual device, after clipping it and performing safety checks.

The system in charge of the signal flow is the Signal Flow Manager. The user can select the active systems for the individual stages in the individual channels by writing its registers.

Any value propagating through the signal flow stages has a type associated with it (see Unit Type Unit Type "Channel Value"), so not all combination of stage Systems are valid – if a system receives a value of a type it cannot process, it will output zero.

A brief overview of available stage systems by stage follows:

- Input Stage:
  - Static Input, for constant values set by the user.
  - Analog Input, for generating values by sampling the analog inputs of the driver.
  - Signal Generator, a customisable generator of simple signals, such as a rectangular pulse, or a sine wave.
  - Vector Pattern Unit, for repeating sets of values which can be saved to the non-volatile memory of the controller.
- Input Conditioning Stage:
  - Input Conditioning, which applies pre-defined gain and offset to the value;
- Control Stage:
  - Open Loop, to feed unchanged current values forward to the output.
  - Lens Compensations, to control lenses in current or focal power mode.
    Attention
      If unit of input stage does not match with the selected control stage unit, 0 is propagated to the output as default.
- Output Conditioning Stage:
  - Output Conditioning, a system which just forwards unchanged values to the next stage currently acting as placeholder.
- Output Stage:
  - Linear Output, currently the only available Output stage system, which sets after checking the value it receives to an appropriate DAC.

Note
  See the default values of the Signal Flow Manager registers for the default configuration of the signal flow.