Module tile 

Tile data: the 384 slots at 0x8000, sixteen bytes each.

Slots and indices

A tilemap byte is eight bits, so it names one of 256 tiles, but there are 384. LCDC bit 4 chooses which window of 256 it names, and the two windows overlap in the middle:

Block	Address	Slot	Base8000	Base8800
0	8000-87FF	0-127	index 0-127	out of reach
1	8800-8FFF	128-255	index 128-255	index 128-255
2	9000-97FF	256-383	out of reach	index 0-127

Objects ignore the bit and always read as Base8000, so putting the background on Base8800 gives each a private block and leaves block 1 shared, putting all 384 within reach at once.

Writing here addresses a slot, which means the same tile whichever mode is set; index converts one to the byte a map needs. See https://gbdev.io/pandocs/Tile_Data.html.

Enums

Addressing

Which 256 slots a tilemap byte names, from LCDC bit 4.

Constants

SLOT_COUNT

Tile slots in one VRAM bank.

Functions

addressing

Which window LCDC currently selects for the background and window layers.

index

The tilemap byte that names slot under mode, if mode reaches it.

set_addressing

Select the window for the background and window layers.

slot

The slot a tilemap byte of index names under mode.

write

Write one tile into slot.

write_all

Write data into consecutive slots from first.