unit_AW3641E.hpp File Reference

AW3641E Unit for M5UnitUnified. More...

#include <M5UnitComponent.hpp>

Go to the source code of this file.

Classes
class	m5::unit::UnitAW3641E
	1A flash LED driver controlled via EN-pin pulse protocol More...
struct	m5::unit::UnitAW3641E::config_t
	Settings for begin. More...

Namespaces
namespace	m5
	Top level namespace of M5Stack.
namespace	aw3641e
	For AW3641E.

Enumerations
enum class	m5::unit::aw3641e::SwitchPosition : uint8_t { Flash , Torch }
	Position of the on-board mode selection switch (silkscreen S1, SPDT type) More...
enum class	m5::unit::aw3641e::Brightness : uint8_t {   Pct100 , Pct90 , Pct80 , Pct70 ,   Pct60 , Pct50 , Pct40 , Pct30 }
	Flash brightness level (percentage of I_FLASH; Flash mode only) More...

Functions
constexpr uint8_t	m5::unit::aw3641e::to_pulse_count (const Brightness b)
	Translate a Brightness level to the AW3641E rising-edge pulse count.

Variables
constexpr uint32_t	m5::unit::aw3641e::PULSE_HIGH_US {4}
	Minimum logic-high pulse width in microseconds (T_HI; datasheet 0.75-10 µs)
constexpr uint32_t	m5::unit::aw3641e::PULSE_LOW_US {4}
	Minimum logic-low pulse width in microseconds (T_LO; datasheet 0.75-10 µs)
constexpr uint32_t	m5::unit::aw3641e::PULSE_OFF_US {600}
	Minimum EN-low delay required before a pulse sequence (T_OFF; datasheet > 500 µs)
constexpr uint16_t	m5::unit::aw3641e::FLASH_MAX_DURATION_MS {220}
	Maximum duration for a single flash() call in milliseconds.
constexpr uint16_t	m5::unit::aw3641e::TORCH_MAX_DURATION_MS {1300}
	Maximum duration for a single torch() call in milliseconds.

Detailed Description

AW3641E Unit for M5UnitUnified.

Driver for UnitFlashLight (SKU:U152). AW3641E is an Awinic 1A flash LED driver controlled via a 1-wire EN pulse protocol.

Enumeration Type Documentation

Brightness

enum class m5::unit::aw3641e::Brightness : uint8_t

strong

Flash brightness level (percentage of I_FLASH; Flash mode only)

Note

On UnitFlashLight (U152) with R_SET = 100 kΩ and R_SENSE = 0.22 Ω, I_FLASH(100%) is approximately 584 mA. Torch mode uses a fixed ~214 mA regardless of this setting.

Enumerator
Pct100	100% of I_FLASH
Pct90	90%
Pct80	80%
Pct70	70%
Pct60	60%
Pct50	50%
Pct40	40%
Pct30	30% of I_FLASH

SwitchPosition

enum class m5::unit::aw3641e::SwitchPosition : uint8_t

strong

Position of the on-board mode selection switch (silkscreen S1, SPDT type)

Note

The switch is wired between the AW3641E FLASH pin and either +5V (Flash side) or GND (Torch side). It is NOT connected to the host MCU and cannot be read from software, so this enum is a DECLARATION of the physical switch position — the library trusts what the user configured. A mismatch between the declared value and the physical switch results in undefined optical behavior.

Enumerator
Flash	S1 = Flash side. FLASH pin = +5V. Use flash() to fire pulse-controlled flashes.
Torch	S1 = Torch side. FLASH pin = GND. Use torch() to drive continuous illumination.

Function Documentation

to_pulse_count()

uint8_t m5::unit::aw3641e::to_pulse_count ( const Brightness b )

constexpr

Translate a Brightness level to the AW3641E rising-edge pulse count.

Parameters

b	Brightness level

Returns

Pulse count in range 1..8 (Pulse 1 = 100% / 220 ms, Pulse 8 = 30% / 220 ms)

Note

Only Pulse 1-8 (Ms220 timeout) is exposed by this library; the chip's Pulse 9-16 (1.3 s timeout) range is not used because thermal protection causes the LED to dim before the timeout expires at higher currents.

Variable Documentation

FLASH_MAX_DURATION_MS

uint16_t m5::unit::aw3641e::FLASH_MAX_DURATION_MS {220}

constexpr

Maximum duration for a single flash() call in milliseconds.

Note

Matches the AW3641E Flash mode hardware timeout for Pulse 1-8 (220 ms). For longer continuous on-time use torch() instead.

TORCH_MAX_DURATION_MS

uint16_t m5::unit::aw3641e::TORCH_MAX_DURATION_MS {1300}

constexpr

Maximum duration for a single torch() call in milliseconds.

Note

Library-side safety cap. Torch mode itself has no hardware time limit (EN=HIGH continuously drives ~214 mA), but the driver clamps long durations to avoid runaway on-time bugs.