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	Number	Readable	Writable	Description
Tilemap Offset X MSB Register	$2F	Yes	Yes	Sets the pixel offset (two high bits) used for drawing Tilemap graphics on the screen.
Tilemap Offset X LSB Register	$30	Yes	Yes	Sets the pixel offset (eight low bits) used for drawing Tilemap graphics on the screen.
Tilemap Offset Y Register	$31	Yes	Yes	Sets the pixel offset used for drawing Tilemap graphics on the screen.
LoRes X Offset Register	$32	Yes	Yes	Pixel X offset (0..255) to use when drawing LoRes Layer.
LoRes Y Offset Register	$33	Yes	Yes	Pixel Y offset (0..191) to use when drawing LoRes Layer.
Sprite port-mirror Index Register	$34	Yes	Yes	Selects sprite index 0..127 to be affected by writes to other Sprite ports (and mirrors).
Sprite port-mirror Attribute 0 Register	$35	No	Yes	Nextreg port-mirror to write directly into "byte 1" of Sprite Attribute Upload ($xx57 / 87).
Sprite port-mirror Attribute 1 Register	$36	No	Yes	Nextreg port-mirror to write directly into "byte 2" of Sprite Attribute Upload ($xx57 / 87).
Sprite port-mirror Attribute 2 Register	$37	No	Yes	Nextreg port-mirror to write directly into "byte 3" of Sprite Attribute Upload ($xx57 / 87).
Sprite port-mirror Attribute 3 Register	$38	No	Yes	Nextreg port-mirror to write directly into "byte 4" of Sprite Attribute Upload ($xx57 / 87).
Sprite port-mirror Attribute 4 Register	$39	No	Yes	Nextreg port-mirror to write directly into "byte 5" of Sprite Attribute Upload ($xx57 / 87).
Palette Index Register	$40	Yes	Yes	Chooses an palette element (index) to manipulate with
Palette Value Register	$41	Yes	Yes	Use to set/read 8-bit colours of the ULANext palette.
Enhanced ULA Ink Color Mask	$42	Yes	Yes	Specifies mask to extract ink colour from attribute cell value in ULANext mode.
Enhanced ULA Control Register	$43	Yes	Yes	Enables or disables Enhanced ULA interpretation of attribute values and toggles active palette.
Enhanced ULA Palette Extension	$44	Yes	Yes	Use to set 9-bit (2-byte) colours of the Enhanced ULA palette, or to read second byte of colour.
Transparency colour fallback Register	$4A	Yes	Yes	8-bit colour to be used when all layers contain transparent pixel.
Sprites Transparency Index Register	$4B	Yes	Yes	Index into sprite palette (of "transparent" colour).
Tilemap Transparency Index Register	$4C	Yes	Yes	Index into Tilemap palette (of "transparent" colour).
Memory management slot 0 bank	$50	Yes	Yes	Selects the 8k-bank stored in 8k-slot 0 (see Memory map).