PXD10RM Datasheet, PDF (335/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

The sections are analogous to the structure of communications modules, such as the FlexCAN, where one
part of the module is configured to connect with the communications bus through bit-timing, parity, baud
rate, etc., while a different part is used to store the data content and message identifiers.
The configuration of the lower section is dependent on the specific TFT LCD panel and optional real-time
video hardware that are attached to the DCU inputs and outputs. In most cases, this is configured once for
the hardware in use before the DCU is enabled. When active, this section automatically:
• Calculates the relevant graphical content for each pixel
• Fetches the source graphics from memory using its internal DMA channels (labelled CH1 to CH4)
• Converts the graphic value of each fetched pixel into full quality color format (if required)
• Calculates the required pixel value by blending the values of up to four separate graphics
• Performs a gamma correction on the pixel value (if required)
• Sends the pixel value to the TFT LCD display over its data bus
• Sets flags to indicate end of frame, buffer threshold, and other status changes
The upper section describes the characteristics of the graphics to be displayed on the panel and how they
are blended together. The DCU manages the graphical content of the panel through sets of registers called
layers. There are 16 layers available in the DCU and each contains the following information:
• Horizontal and vertical size of graphic
• Position of graphic on the panel
• Address of graphic in memory
• Color encoding format and color palettes (if required)
• Type and depth of blending
• Range of colors identified for chroma blending
• Tile size
The values in these registers may be changed at any time, and the panel content will be updated when the
next full frame is ready to be displayed. The layers are set to a fixed priority, and this is used by the lower
section to define which layers are blended, in which order, on the panel.
The upper section also contains configuration registers for a cursor graphic, the default background color,
interrupt enables, test graphic, and simple register protection settings.
12.1.2 Features
The DCU has these features:
• Full RGB888 output to TFT LCD panel
• 16 graphics layers, a default background color layer and a cursor layer with integrated blinking
option
• Blending of each pixel using up to 4 source layers dependent on size of panel
• Programmable panel size up to a maximum of Wide VGA (800 x 480)
• Gamma correction with 8-bit resolution on each color component
• Safety mode for tagging pixels on highest priority layers
Freescale Semiconductor
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
12-3