System ROM tables

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All (?) system ROMs provide lookup tables for games to use. Red lines represent zero.

METRIC_DATA ($C02000)

Actually two 64, 64-entry byte tables at $C02000 and $C03000 which might be used for animation easing/smoothing.

$C02000

Goes from 64~0 to 64~32.

Lut metric2.png

$C03000

Goes from 0~63 to 63~89.

Lut metric3.png

SIN_DATA ($C04000)

Two identical glitchy half-sine tables of 128 signed 16-bit words. The value overflows for one entry (at the top of the curve). There's also a glitch with two very close values in the 3rd quarter of each table.

Lut sine.png

RND_DATA ($C04200)

256 "random" bytes. Do all values appear once ?