TVP4020
Programmers Reference Manua
TVP4010 and TVP4020 Differences
299
TVP4020 adds extra control over formatting of the framebuffer color
when blending. The AlphaBlendMode register allows control over the
way that framebuffer data is mapped to the internal color format. This
can prevent visual artifacts when blending with a dithered framebuffer.
F5.8
Color Formats
TVP4020 performs all internal color calculations at true color accuracy,
where TVP4010 performed 3D calculations at 5 bits per color
component.
An additional pixel and texel size has been added to TVP4020, 24 bits,
which has 8 bits of red, green , and blue, but no alpha channel. All pixel
operations are available at this size except block fills which are restricted
to colors which have all bytes the same value (i.e. shades of grey). This
restriction is due to the operation of the memory devices.
F5.9
Miscellaneous
TVP4020 will calculate the value of FBSourceOffset from an XY delta
value, removing a multiply from the set-up needed for a copy operation.
The relative offset field in the FBReadMode register is also in the
PackedDataLimits register, the one used will be the last one set before a
primitive is drawn. This reduces the number of registers that have to be
written for a copy operation.
A register has been added to the TVP4020 PCI interface which can be
used to determine when the chip is idle. If the idle status is set then
TVP4020 will process the next command without delay. It does not
mean that all previous operations have completed and data written to
memory.
An additional TVP4020 register can be used to configure a number of
controls that are normally set by separate registers. The Config register
controls parts of the FBReadMode, FBWriteMode, LogicalOpMode, and
ColorDDAMode, registers.
Содержание TVP4020 PERMEDIA 2
Страница 1: ...Texas Instruments TVP4020 PERMEDIA 2 Programmer s Reference Manual Issue 4 ...
Страница 47: ...Memory I O and Organization TVP4020 Programmers Reference Manual 38 Texture address TextureBaseAddress T W S ...
Страница 284: ...TVP4020 Programmers Reference Manual A Gouraud Shaded Triangle 275 ...
Страница 292: ...TVP4020 Programmers Reference Manual Register Tables 283 ...
Страница 314: ...TVP4020 Programmers Reference Manual Index 305 ...
Страница 315: ...Index TVP4020 Programmers Reference Manual 306 Index ...
Страница 323: ...Index TVP4020 Programmers Reference Manual 314 ...