Peripherals

This page collects optional hardware used around the iDotMatrix/WLED system. Peripherals are documented separately from the controller and matrix because electrical requirements and support status can differ substantially.

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Buzzer

Starting with 0.9.3, buzzer hardware is not owned by iDotMatrix. Sound support is provided by the separate WLED Buzzer Usermod.

The external Usermod is responsible for:

• buzzer GPIO allocation;
• Active/Passive hardware selection;
• trigger polarity;
• LEDC and tone generation;
• volume;
• playback timing and built-in sound definitions.

iDotMatrix only requests logical sounds through the optional weak-link bridge exported by WLED Buzzer Usermod 0.1.0 / final.

The iDotMatrix settings page contains one Buzzer → Enable checkbox and the orange note Requires the WLED Buzzer Usermod. If the external Usermod is not included in the firmware, the checkbox is disabled.

Current sound mapping:

Event	Sound ID
Alarm	alarm loop
Program / Schedule	notification
Countdown completion	triple_beep
BLE connection	connect
BLE disconnection	disconnect

For wiring, buzzer module types, trigger polarity and electrical requirements, use the documentation of the WLED Buzzer Usermod rather than configuring those values in iDotMatrix.

RTC modules

Project status: Model-specific / catalog section

An RTC is not required for the core BLE protocol or matrix renderer: normal WLED timekeeping can provide the runtime clock.

RTC boards may nevertheless be useful in standalone or future hardware configurations. Each RTC must be documented by exact chip/module because voltage levels, I2C pull-ups, backup-battery behavior and library support differ.

For each RTC entry record:

• RTC chip;
• module/board model;
• operating voltage;
• I2C voltage and pull-up arrangement;
• backup battery/supercapacitor;
• tested controller;
• whether time survives power loss;
• any level shifting required;
• project integration status.

Do not mark a generic “RTC” as supported without identifying the actual device.

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Audio / microphone input

Project status: Depends on the WLED AudioReactive hardware/profile

The iDotMatrix Usermod can consume WLED AudioReactive data. The physical microphone / audio-front-end is therefore primarily a WLED hardware concern.

The Usermod sees:

• overall audio level for LEVEL effects;
• 16 WLED GEQ bands, combined into 8 logical iDotMatrix FFT bands.

When documenting an audio board or microphone, include:

• microphone/front-end model;
• analog or digital interface;
• controller pins;
• WLED AudioReactive profile/settings;
• observed noise floor;
• whether LEVEL and FFT effects both work correctly.

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Level shifters and driver stages

Some combinations may require external interface electronics, for example:

• 3.3 V -> 5 V logic level shifting;
• HUB75 buffering;
• MOSFET/transistor buzzer drivers;
• power distribution;
• I2C level conversion.

These components should be documented with the board/panel they were needed for. A successful test without a level shifter on one panel must not be generalized to every panel using the same nominal interface.

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MatrixPortal LIS3DH accelerometer

Project status: Available on the MatrixPortal S3 hardware, intentionally outside the iDotMatrix Usermod

The MatrixPortal S3 includes an LIS3DH accelerometer. Automatic display orientation is a controller/WLED presentation concern rather than an iDotMatrix BLE-protocol function, so it is intentionally not coupled to this Usermod.

If automatic 0°/90°/180°/270° orientation is developed, the project direction is to implement it as a separate WLED Usermod. That keeps orientation applicable to native WLED effects and other content as well as iDotMatrix output, avoids adding LIS3DH dependencies to C3/other targets, and leaves room for additional accelerometer backends later.

A future implementation should use stable-orientation timing and hysteresis rather than rotating on individual noisy samples.

Adding a peripheral

Please provide:

1. exact model/part number;
2. photograph or product link;
3. supply/interface voltage;
4. connection diagram or pin assignment;
5. tested controller;
6. firmware/WLED version;
7. observed result;
8. any required external circuitry.

See Hardware Compatibility Report.

For Alarm, iDotMatrix requests looping triple_beep. WLED Buzzer Usermod 0.1.0 final keeps the one-shot sound unchanged and applies a 550 ms trailing gap only when another repeat follows, preventing adjacent Alarm groups from running together.