pnx1500 NXP Semiconductors, pnx1500 Datasheet - Page 622

• Manufacturer Part Number: pnx1500
• Description: Pnx15xx Series Connected Media Processor
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Volume 1 of 1
3. Operation
PNX15XX_SER_3
Product data sheet
2.3.4 Patterns
2.3.5 Transparency
2.3.6 Block Writes
3.1.1 Alpha Blending
3.1 Register Programming Guidelines
Option 1 is used for normal screen-to-screen operations such as a source-to-
destination copy. Option 2 is used for a host-to-screen copy when the source data is a
full color bitmap. Option 3 is used for color expanding a monochrome bitmap. The
monochrome bitmap will be expanded to full color using the foreground and
background color registers within the drawing engine. Option 4 is similar to Option 3
except that it is designed to handle tightly packed fonts, which are used to render text.
A three-bit field is used to select the appropriate source data option. Option 5 is
similar to Option 2 except that the data provided on the MMIO bus is either packed
4 bit alpha or packed 8-bit alpha information.
The drawing engine provides an 8-by-8 pattern or “brush.” The pattern is always
locked to the screen. This pattern can be solid, monochrome, or full color. If the
pattern is solid, the color value will be taken from the foreground color register. A
monochrome pattern is stored in system memory as two
monochrome data. This monochrome data is written to the drawing engine where it is
color expanded to the appropriate color depth and stored in the pattern RAM. A full
color pattern will be directly transferred from system memory into the pattern RAM.
Only one pattern may be stored in the pattern RAM at a given time.
The drawing engine supports transparency on either source or destination data.
Transparent patterns are not supported. Transparency works by comparing either
source or destination to a value stored in a color compare register and then allowing
(or disallowing) a write to occur based on the result of the compare. Transparency is
implemented on a per-pixel basis: at 8 bpp one byte is used for the compare value. At
16 bpp one word is used for the compare, and at 32 bpp the entire color compare
register is used for the compare. A transparency mask is provided in order to exclude
certain bits within a pixel from being used in the color compare.
Block writes are not supported by the drawing engine.
The drawing engine supports alpha blending of Source, Destination, and a global
SurfaceAlpha. The following destination formats are useful with alpha blending:
4. Source data is provided by the processor via the MMIO bus and is a
5. Source data is provided by the processor via the MMIO bus and is Alpha
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monochrome text font.
Blending data.
RGB:565(16 bit per pixel)
RGB:4444(16 bit per pixel)
Rev. 3 — 17 March 2006
Chapter 20: 2D Drawing Engine
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
DWORD
PNX15xx Series
s (64 bits) of
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