Devices & Vectors

Uxn can communicate with a maximum of 16 devices, each device has 16 ports, each port handles a specific I/O message. Ports are mapped to the devices memory page, which is located outside of the main addressable memory.

Uxn is non-interruptible, vectors are locations in programs that are evaluated when certain events occur. A vector is evaluated until a BRK opcode is encountered, no new events will be triggered while a vector is evaluated, but events may be queued. All programs begin by executing the reset vector located at 0x100. Only one vector is executed at a time. The content of the stacks are preserved between vectors.

|0100

	( set a vector )
	;on-mouse .Mouse/vector DEO2

BRK

@on-mouse ( -> )

	( read mouse state )
	.Mouse/state DEI ?&on-touch BRK 

&on-touch ( -> )

	( A mouse button was pressed )

BRK

For example, the address stored in the Mouse/vector port points to a part of the program to be evaluated when the cursor is moved, or a button state has changed.

Incoming: uxntal reference