Event Vocabulary

The structured events every board shares. Outbound events arrive through the onEvent callback as { kind, payload } objects; inbound events are sent with dispatch(kind, payloadJson). Peripheral-specific kinds are documented on each peripheral page.

Outbound (emulator → host)

audio.samples

Interleaved PCM audio samples were produced.

Payload

Field	Type	Description
`sample_count`	u64	Number of samples in the batch.

gpio.change

A GPIO output pin changed level.

Payload

Field	Type	Description
`level`	boolean	New logical level (`true` = high).
`pin`	u32	Pin number within the port.
`port`	u32	GPIO port index.

irq.lower

An interrupt line was deasserted.

Payload

Field	Type	Description
`line`	u32	NVIC IRQ number (Cortex-M) or GIC SPI number (Cortex-A).

irq.raise

An interrupt line was asserted (pended).

Payload

Field	Type	Description
`line`	u32	NVIC IRQ number (Cortex-M) or GIC SPI number (Cortex-A).

uart.tx

Bytes transmitted by the guest on a UART/serial port.

Payload

Field	Type	Description
`bytes`	bytes	Transmitted bytes.
`port`	u32	Logical UART port index (0 = primary console).

video.frame

A completed display frame is available; fetch pixels via the framebuffer API.

Payload

Field	Type	Description
`height`	u32	Frame height in pixels.
`width`	u32	Frame width in pixels.

Inbound (host → emulator)

joypad

Game controller state for console boards.

Payload

Field	Type	Description
`bits`	u32	Packed button bitmask.

uart.rx

Bytes from the host (terminal keystrokes) delivered to the guest UART RX line.

Payload

Field	Type	Description
`bytes`	bytes	Received bytes.