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Class OpenSkyhawk::Dimmer

ClassList > OpenSkyhawk > Dimmer

PWM dimmer output — the DcsBios::Dimmer equivalent. Maps a 16-bit DCS-BIOS value to PWM duty on a direct GPIO timer pin. More...

  • #include <Dimmer.h>

Inherits the following classes: OpenSkyhawk::AnalogOutput

Public Types

Type Name
typedef uint16_t(*)(uint16_t value) ScaleFn
Scale function: raw 16-bit DCS value → 16-bit value handed to writeAnalog().

Public Functions

Type Name
Dimmer (uint16_t controlId, PinRef pin, ScaleFn scale=nullptr)
Construct and register a dimmer.
virtual void configure () override
Configure the output pin and drive duty to 0.

Public Functions inherited from OpenSkyhawk::AnalogOutput

See OpenSkyhawk::AnalogOutput

Type Name
virtual void onControlPacket (uint16_t controlId, uint16_t value)
Match, decode, dedup, then apply() . Called byPanelGroup for every CTRL_BCAST packet.

Public Functions inherited from OpenSkyhawk::OutputBase

See OpenSkyhawk::OutputBase

Type Name
virtual void configure ()
Configure hardware pins for this output.
OutputBase * next () const
Next output in the list; nullptr at end.
virtual void onControlPacket (uint16_t controlId, uint16_t value) = 0
Called for every non-null ControlPacket in a CTRL_BCAST frame.
virtual void update ()
Called every PanelGroup::loop() iteration.

Public Static Functions inherited from OpenSkyhawk::OutputBase

See OpenSkyhawk::OutputBase

Type Name
OutputBase * head ()
Head of the self-registered linked list.

Protected Functions

Type Name
virtual void apply (uint16_t value) override
Write the value as PWM duty. Called by the base when the decoded value changed.

Protected Functions inherited from OpenSkyhawk::AnalogOutput

See OpenSkyhawk::AnalogOutput

Type Name
AnalogOutput (uint16_t controlId, uint16_t mask=0xFFFF, uint8_t shift=0)
Construct the base. Registration into PanelGroup 's output list isOutputBase 's.
virtual void apply (uint16_t value) = 0
Sink hook — called with the decoded value, only when it changed.

Protected Functions inherited from OpenSkyhawk::OutputBase

See OpenSkyhawk::OutputBase

Type Name
OutputBase ()
Registers this instance into the linked list.

Detailed Description

Primary use is backlight zone dimming: the low-side MOSFET gate of an LED zone, one Dimmer per zone (PA6 / PA7 on the PanelGroup base). The A-4E-C drives five such values — LIGHTS_CONSOLE, LIGHTS_INSTRUMENTS, LIGHTS_FLOOD_RED, LIGHTS_FLOOD_WHITE, APG53A_GLOW — and any other PWM-proportional load works the same way.

The AnalogOutput base owns matching, decoding and change dedup; this class is the sink: apply() writes through PinRef::writeAnalog() (16-bit in; the GPIO path outputs value >> 8 as 8-bit duty). An optional scale function reshapes the value first — perceptual dimming curves, inversion.

Takes a PinRef like every control class and checks its type: brightness comes from an STM32 timer channel, so configure() requires a direct GPIO that has one. Anything else (MCP23017, ShiftBus, a GPIO with no timer) is logged and leaves the output disabled rather than degrading silently — writeAnalog() is a no-op through an expander, and analogWrite() on a non-timer GPIO collapses to an on/off threshold. Software PWM through an expander is deliberately not offered: those bits change once per loop or bus transfer, so a duty cycle there would flicker and keep the bus busy, where timer PWM costs no CPU.

On/off threshold behaviour is LED's job, not this class's. Polarity is not invertible — the zone-switch hardware standard is fixed (higher duty = brighter); an inverted drive is a scale function, not a constructor flag.

Duty is driven to 0 during configure() and stays there (zone dark) until a CTRL_BCAST packet with a matching controlId arrives.

Public Types Documentation

typedef ScaleFn

Scale function: raw 16-bit DCS value → 16-bit value handed to writeAnalog(). 

using OpenSkyhawk::Dimmer::ScaleFn =  uint16_t (*)(uint16_t value);

Public Functions Documentation

function Dimmer

Construct and register a dimmer. 

OpenSkyhawk::Dimmer::Dimmer (
    uint16_t controlId,
    PinRef pin,
    ScaleFn scale=nullptr
)

Parameters:

  • controlId DCS-BIOS output address (A_4E_C_* from A4EC_OutputIds.h — the full 16-bit word; the matching *_AM mask is 0xffff for these outputs).
  • pin PinRef for the PWM output: a direct STM32 GPIO on a timer channel (the zone-switch MOSFET gate) — PinRef(PA6) / PinRef(PA7) on the base.
  • scale Optional reshaping of the 16-bit value before it is written. nullptr (default) = identity.

function configure

Configure the output pin and drive duty to 0. 

virtual void OpenSkyhawk::Dimmer::configure () override

Called by PanelGroup::setup() after chip.init(). Requires a direct GPIO on a timer channel; otherwise logs on DiagSerial and disables the output (no writes at all). On success the pin becomes an output at duty 0, so the zone stays dark until the first matching CTRL_BCAST.

Implements OpenSkyhawk::OutputBase::configure

Protected Functions Documentation

function apply

Write the value as PWM duty. Called by the base when the decoded value changed. 

virtual void OpenSkyhawk::Dimmer::apply (
    uint16_t value
) override

Applies the scale function, then skips the write when the resulting 8-bit duty equals the last one written — different 16-bit values map to the same duty. No-op while the output is disabled.

Implements OpenSkyhawk::AnalogOutput::apply

The documentation for this class was generated from the following file Firmware/Libraries/PanelGroup/Outputs/Dimmer/Dimmer.h