2D-Animation and Composition Engine (ACE) and Graphics … · 2016. 3. 12. · TM External Use 1 Session Introduction •This session gives an introduction of the Display Control

External Use

TM

2D-Animation and Composition Engine

(ACE) and Graphics Subsystem for Vybrid

Controllers and Layerscape Processors

FTF-IND-F0110

A P R . 2 0 1 4

Juan Gutierrez | SW Apps Engineer

Feras Hamdan | Sr. Electronics Engineer, Apps, R&D

Francisco Sandoval | Field Applications Engineer

TM

External Use 1

Session Introduction

• This session gives an introduction of the Display Control Unit

(DCU) (2D-ACE) Graphics Subsystem.

• This session gives an overview of the DCU features.

• This session is presented by an Applications SW Engineer that

ported the HVAC demo on Vybrid Controller Solutions based on

ARM® Technology.

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External Use 2

Session Objectives

• After completing this session you will be able to :

− Understand, at a high level, the capabilities of the DCU module and how

it can be used in your application.

− Apply the knowledge gained in this presentation to start using the DCU

module in your application.

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External Use 3

Agenda

• Display Control Unit (2D-ACE functionality)

• DCU Layers

• Modes of Operation

• TFT LCD panel configuration

• Blending priority of the layers

• Graphics and Data Formats

• Indexed colors format

• Alpha and Chroma-key blending

• Gamma correction

• Hardware Cursor

• Color Look Up Tables (CLUT)/Tile RAM

• Special DDR mode

• Run Length Encoding (RLE) Mode

• Error detection

• Safety Mode

• Parallel Data Interface

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External Use 4

Display Control Unit (2D-ACE functionality)

• System that fetches graphics and displays them on a TFT LCD

panel

• The final panel contents are created by compositing and blending

these graphics

• The graphics:

− are directly read from memory (internal or external) using DMA

− may be encoded in a variety of formats

• Capable of displaying real time video from an external video source

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External Use 5

DCU on Vybrid devices

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External Use 6

DCU on Vybrid devices

DCU4 is a Master on NIC and can

access directly any memory device

connected as slave like OCRAM and

QSPI

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External Use 7

DCU block diagram

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External Use 8

DCU Layers

• A layer is the mechanism by which the graphical content is managed and displayed on the panel

• 64 layers (9 CTRLDESCLx registers): − Height & width of the graphic (pixels)

− Position on the panel (x,y)

− Transparency

− Tile

− Color format and CLUT (if required)

− Type and depth of blending

− Range of colors for chroma blending

− Address in memory (32 bits)

• 1 background color layer

• 1 cursor layer

Height

Width

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External Use 9

DCU Layers




− Transparency

− Tile






• 1 cursor layer

(x , y)

Can also be

placed in

negative X and

Y directions.

Pixels off the

panel are

ignored.

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External Use 10

DCU Layers




− Transparency

− Tile






• 1 cursor layer

Alpha

blending with

8-bit

resolution

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External Use 11

DCU Layers




− Transparency

− Tile






• 1 cursor layer

Layers 0 to 7

and 56 to 63

have support

for Tile mode

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External Use 12

DCU Layers




− Transparency

− Tile






• 1 cursor layer

Indexed (RGBA8888 CLUT)

..

..APAL881,2,4,8 bpp

Direct

..RGB565, ..ARGB4444,

..ARGB1555, ..RGB888,

..ARGB8888, ..YUV4:2:2

Special

..A4, A8

..LO4, LO8.

..RLE

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External Use 13

DCU Layers




− Transparency

− Tile



− Range of colors for chroma-blending



• 1 cursor layer

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External Use 14

Modes of Operation

• DCU Off

− All the logic is reset to reduce power

• Normal Mode

− Displays and blends graphics in layer descriptor

• PDI Mode (Parallel Data Interface)

− Fetch video from external video source and combines it with the graphics

on the layers

• Color Bar

− Used for testing purposes

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External Use 15

TFT LCD panel configuration

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External Use 16


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External Use 17


/********************************************************************/ /* DCU0 pin initialization. * Enables all of the DCU0 pins used for the TWR-LCD-RGB. */ #define IOMUX_DCU0_PAD_INIT IOMUXC_PTE_MUX_MODE(1) | IOMUXC_PTE_SPEED(2) | IOMUXC_PTE_DSE(4) | IOMUXC_PTE_OBE_MASK void dcu0_pin_init(void) { /* Enable the 8 DCU_Rn signals */ IOMUXC->PTE5 = IOMUXC->PTE6 = IOMUXC->PTE7 = IOMUXC->PTE8 = IOMUXC->PTE9 = IOMUXC->PTE10 = IOMUXC->PTE11 = IOMUXC->PTE12 = IOMUX_DCU0_PAD_INIT; /* Enable the 8 DCU_Gn signals */ IOMUXC->PTE13 = IOMUXC->PTE14 = IOMUXC->PTE15 = IOMUXC->PTE16 = IOMUXC->PTE17 = IOMUXC->PTE18 = IOMUXC->PTE19 = IOMUXC->PTE20 = IOMUX_DCU0_PAD_INIT; /* Enable the 8 DCU_Bn signals */ IOMUXC->PTE21 = IOMUXC->PTE22 = IOMUXC->PTE23 = IOMUXC->PTE24 = IOMUXC->PTE25 = IOMUXC->PTE26 = IOMUXC->PTE27 = IOMUXC->PTE28 = IOMUX_DCU0_PAD_INIT; /* Enable the PCLK signal */ IOMUXC->PTE2 = IOMUX_DCU0_PAD_INIT; /* Enable the DCU control signals */ IOMUXC->PTE0 = /* HSYNC */ IOMUXC->PTE1 = /* VSYNC */ IOMUXC->PTE3 = /* No DE */ } /********************************************************************/

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External Use 18


void dcu_init(DCU_Type * module, uint32_t div, uint8_t mode) { uint32_t i; /* Enable the DCU0 clocks in the CCM */ . . . /* Set the background color to gray */ module->BGND = 0x0000FF00; /* Configure the DCU for the TWR-LCD-RGB panel */ module->DISP_SIZE = DCU_DISP_SIZE_DELTA_Y(272) | DCU_DISP_SIZE_DELTA_X(480/16); module->HSYN_PARA = DCU_HSYN_PARA_BP_H(2)|DCU_HSYN_PARA_PW_H(41)|DCU_HSYN_PARA_FP_H(0x29); module->VSYN_PARA = DCU_VSYN_PARA_BP_V(2)|DCU_VSYN_PARA_PW_V(10)|DCU_VSYN_PARA_FP_V(10); module->DIV_RATIO = div; /* Panel frequency */ module->SYNPOL = DCU_SYNPOL_INV_VS(1) | DCU_SYNPOL_INV_HS(1);/*Invert H and V signals */ /* initialize all layers to be off */ for(i=0;i<64;i++) *(uint32_t *)(CTRLDESCL0_3 + (i*64)) = 0; module->DCU_MODE = DCU_MODE_MODE(mode) | DCU_MODE_RASTER_EN(1); /* Set the DCU mode */ module->UPDATE_MODE |= DCU_UPDATE_MODE_READREG(1); /* Initiate manual refresh */ /* DCU can automatically updates the panel OR only when commanded */ /* The first tile is always manually but now we can configure it to be automatic */ while (module->UPDATE_MODE & DCU_UPDATE_MODE_READREG(1)); module->UPDATE_MODE |= DCU_UPDATE_MODE_MODE(1); /* Initiate automatic update */ }

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External Use 19

Blending priority of the layers

• The layers available in the DCU are each fixed in priority order.

− Layer 0 has the highest priority.

• At each pixel position up to six layers may be blended.

− Layers below the lowest priority pixel are not visible.

− The blending settings for the lowest priority pixel are ignored.

Pixel ignored

Selected pixels in

blend stack Layers active at

pixel position (x,y)

Blended pixel

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External Use 20

Blending priority of the layers

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External Use 21

Layer Size

• The size of each layer is defined by:

− CTRLDESLn_1[HEIGHT], CTRLDESLn_1[WIDTH]

• The WIDTH field has a restriction on the value it can take

− Invalid value make the layer not visible and set PARR_ERR_STATUS1

and PARR_ERR_STATUS flags

− Rule except for 1bpp is:

BPP x WIDTH = 32 x n (an integer multiple of 32)

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External Use 22

Graphics and Data Formats

• There are 5 modes for data described as TRUE RGB color:

− ARGB8888

− RGB888

− RGB565

10000 : 010000 : 11011 ===> 10000100 : 01000001 : 11011110

− ARGB1555

1 : 10100 : 01000 : 11011 ===> 11111111 : 10100101 : 01000010 : 11011110

− ARGB4444

1010:0011:1100:0101 ===> 10101010:00110011:11001100:01010101

• NOTE: The three 16-bit formats (RGB565, ARGB1555, and ARGB4444) are promoted to full 8 bit per component format

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External Use 23

Graphics and Data Formats

• There are 5 indexed color formats:

− 1bpp 2 colors

− 2bpp 4 colors

− 4bpp 16 colors

− 8bpp 256 colors

− APAL8 (16bpp) Alpha[15:8] Offset[7:0]

• The maximum number of colors in the CLUT is defined by the size

of the data stored in the graphic.

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External Use 24

Indexed colors format

1 2 3 3

2 0 1 2

3 2 1 0

2 2 2 1

Pixel data

(2bits)

Indexed color (24bits)

0 0x00FF00FF

1 0x00FF0000

2 0x00FFFFFF

3 0x80FF0000

Pixels in RAM (2BPP LUT)

Lookup table in CLUT RAM

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External Use 25


1 2 3 3

2 0 1 2

3 2 1 0

2 2 2 1

Pixel data Indexed color

0 0x00FF00FF

1 0x00FF0000

2 0x00FFFFFF

3 0x80FF0000

Pixels displayed


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External Use 26


1 2 3 3

2 0 1 2

3 2 1 0

2 2 2 1


0 0x0000FF00

1 0x00FF0000

2 0x00FFFFFF

3 0x80FF0000

Pixels displayed


1 word changed in

LUT RAM!

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External Use 27


1 2 3 3

2 0 1 2

3 2 1 0

2 2 2 1


0 0x00FF0000

1 0x00FF0000

2 0x00FFFFFF

3 0x80FF0000

Pixels displayed


You can have twice

the same color

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External Use 28

Support for YUV422

• Defines the luminance of a pixel and the

color of the pixel (known as chrominance) as

two separate elements.

• DCU supports YUV422 format which uses a

32-bit packet to store 2 pixels so it effectively

behaves as a 16bpp format.

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External Use 29

Alpha and Chroma-key blending

• The blending configuration of each layer is defined by the BB, AB, and TRANS bit CTRLDESCLn_4.

• When BB bit is set, pixels that have an RGB value that fall into the range defined by CTRLDESCLn_4 and CTRLDESCLn_5 are considered to be selected and treated differently to the non-selected pixels in the graphic.

− The BB bit field defines whether the whole graphic, or only certain pixels, should be blended (Chroma-keying).

− The AB bit field defines how any selected and non-selected pixels are blended.

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External Use 30

Defining the Chroma Range

• The range is defined by giving maximum and minimum values for

each color component.

− Red, green and blue have minimum and maximum values.

• If the color of a pixel falls into the range in each of the components,

then it is selected.

Red Green Blue

0 – 255 0 – 255 0 – 255

0 – 0 0 – 255 255 – 255

X X

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External Use 31

Blend options for BB and AB configurations

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External Use 32

Alpha Blending

• Alpha blending is the process of combining a translucent

foreground color with a background color, thereby producing a new

blended column:

A = (BG_pixels x (255 - Alpha)) + (FG_pixels x Alpha)

http://en.wikipedia.org/wiki/File:Alpha_compositing.svg

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External Use 33

No blend

• In this case, the top layer graphic completely overlays the

background layer.

− Chroma-keying = off

− Alpha blending = no blend

1 + =

Layer 2 Layer 1 Panel

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External Use 34

RGB: Alpha blend all

• In this case, the top layer graphic is transparent and the

background layer can be seen through it.

− Chroma-keying = off

− Alpha blending = mode 1

1 + = 50% Transparency


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External Use 35

RGB: Remove selected pixels

• In this case, the pixels selected by the chroma-keying range in the

top layer graphic become invisible and only the remaining pixels

are seen overlaying the background layer.

− Chroma-keying = on

− Alpha blending = no blend

1 + = Remove blue color range


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External Use 36

RGB: Blend selected pixels

• In this case, the pixels selected by the chroma-keying range on the

top layer graphic are alpha blended with the background layer. The

remaining pixels are not blended and overlay the background.



1 + = Blend blue color range with transparency 50%


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External Use 37

RGB: Remove selected pixels, blend the rest

• In this case, the pixels selected by the chroma-keying range on the

top layer graphic are removed from the foreground layer. The

remaining pixels are alpha-blended with the background.



1 + = Remove blue color range, others transparency 50%


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External Use 38

Graphics with alpha included

• The DCU can blend graphics with an embedded alpha channel (ARGB)

• Eight formats are supported

− ARGB8888

32-bit data containing alpha and RGB channels all at 8 bits per color channel

− ARGB4444

16-bit data containing alpha and RGB channels all at 4 bits per color channel

− ARGB1555

16-bit data containing alpha channel of 1 bit (on/off) and RGB channels at 5 bits per color channel

− APAL8

16-bit data containing 8-bit alpha channel and indexed 8bpp color

− Indexed color formats (1, 2, 4, 8 bpp)

These use color look up tables (CLUTs) that contain an alpha component

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External Use 39

ARGB

• No Blend

− In this case the alpha content included

in the layer graphic is ignored.

Pixel selection/chroma-keying = off

Alpha blending = no blend

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External Use 40

ARGB

• Remove Selected Pixels

− In this case, the alpha content included

in the layer graphic is ignored.

−The pixels selected by the chroma-

keying range in the top layer graphic

become invisible and only the

remaining pixels are seen overlaying

the background layer.

Pixel selection/chroma-keying = on

Alpha blending = no blend

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External Use 41

ARGB

• Alpha Blend All

− In this case, the alpha value specified

by the layer is ignored.

− In this case, the colors adopt the alpha

value embedded in the image.


Alpha blending = mode 1

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External Use 42

ARGB

• Image Alpha Active for Selected Pixels

− In this case, the alpha value specified

by the layer is ignored.

−The pixels selected by the chroma-

keying range adopt the alpha value

embedded in the image.



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External Use 43

ARGB

• Image Alpha Active for All Pixels


value embedded in the image and

multiply that value with the layer alpha.



Layer alpha = 0xFF

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External Use 44

ARGB

• Image and Layer Alpha Active for All

Pixels


value embedded in the image and

multiply that value with the layer alpha.



Layer alpha = 0x60

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External Use 45

ARGB

• Image Alpha Active for Non-selected Pixels

− In this case, the pixels selected by the chroma-

keying range in the top layer graphic are

removed from the foreground layer.

− The remaining pixels use the alpha value

embedded in the image and multiply that value

with the layer alpha.



Layer alpha = 0xFF

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External Use 46

Blend options for BB and AB configurations

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External Use 47

Layer Setup

void initLayer(uint8_t layer, void *address, uint32_t size, uint32_t pos)

{

/* size of layer in format height X width */

*(uint32_t *)(CTRLDESCLn_0 + (layer*64)) = size;

/* position in format YxX */

*(uint32_t *)(CTRLDESCLn_1 + (layer*64)) = pos;

/* address of graphic to display in this layer */

*(uint32_t *)(CTRLDESCLn_2 + (layer*64)) = (uint32_t)address;

/* Register value to enable the layer, use ARGB4444 format and set full

transparency in its blended pixels */

*(uint32_t *)(CTRLDESCLn_3 + (layer*64)) = DCU_CTRLDESCL0_3_EN_MASK

| DCU_CTRLDESCL0_3_TRANS(0xFF) /* Set transparency to opaque */

| DCU_CTRLDESCL0_3_BPP(0xC) /* ARGB444 format */

| DCU_CTRLDESCL0_3_AB(0x0) /* blend the whole frame */

| (0x1 << DCU_CTRLDESCL0_3_BB_SHIFT) ;

*(uint32_t *)(CTRLDESCLn_4 + (layer*64)) = 0x00FFFFCC;

*(uint32_t *)(CTRLDESCLn_5 + (layer*64)) = 0x00000040;

}

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External Use 48

Transparency Mode Blending Options

• The DCU includes a special mode where the graphic only contains an alpha component, this is useful for graphics such as fonts or dials that:

− Require anti-aliasing

− May be placed on top of different colored backgrounds

• The color components in this mode are determined at run time

− Allows the definition of a anti-aliased font that can be any color

• As well as the inherent alpha blending contained in the graphic, the five existing DCU blend modes are also applicable

− No blend, Alpha blending only, Chroma-keying only, Alpha and chroma- blend mode 1, Alpha and chroma-blend mode 2

• Allows the DCU to create extremely complex graphical blends using a minimum of CPU processing and data storage

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External Use 49

Transparency Pre-blending

• The transparency mode graphic contains no color information

− Only alpha values are stored

− The front color of the graphic and the rear color of the background are

fetched from dedicated foreground and background registers

• The anti-aliased edges are pre-blended by the DCU to give smooth

edges between the graphic (front color) and its background

(rear color)

1 Blue front color

White rear color Red rear color Stored graphic

Green front color

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External Use 50

Blend options for transparency mode

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External Use 51

Transparency Mode

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External Use 52

Transparency Mode.- without Anti Aliasing

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External Use 53

Transparency Mode.- with Anti Aliasing

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External Use 54

Highlighting Graphics/ Luminance mode

• The DCU provides support for highlighting particular graphics

through a layer luminance offset mode.

− The luminance layer is not a normal display layer, instead it modifies the

values of the colors in the layer below.

− 4bpp and 8bpp encoding is supported and provides a signed addition to

the value of each component of the underlying pixel.

− Typically used to highlight menu items or particular graphic items.

• The highlight area data values behave as signed integers that are

added/saturated to each component of the underlying pixel.

+ =

Graphic layer/s Luminance layer Cursor on panel

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External Use 55

Creating Textures – Tile Mode

• The DCU provides a memory-efficient method of creating a

textured layer by allowing a graphic to be “tiled” within a layer

− Layer size defines the extent of the layer

− Tile size defines the extent of the tile

− The DCU automatically repeats the tile to fill the layer

− Tile mode is only available on layers 0 to 7 and 56 to 63.

• The graphic data for the Tile Mode can be fetched either from the

system memory or from the internal CLUT/Tile memory.

+ =

Layer Tile graphic Layer on panel (before blending)

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External Use 56

Gama Correction - Wiki

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External Use 57

Gamma correction

• For the DCU, Gamma

correction is an arbitrary

transfer function that allows

any intensity level for Red,

Green or Blue to be replaced

by another.

• For example, if the green on a

particular display is too

intense then the table can be

constructed to reduce the

intensity across the range. An

example of this is shown in

the table.

Input Color

(address of

value in table)

Color output to

the display panel

0 0

1 0

2 1

3 1

4 2

And so on through table until

0xFE 0xCF

0xFF 0xD0

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External Use 58

Gamma correction

• Gamma correction is applied universally, so even if a color does not need to be adjusted, the gamma table must be filled in with the same value.

− In the example, the Red intensity will be unaffected by gamma correction.

• Sometimes panels invert the intensity of colors so that 0xFFFFFF may be black rather than white.

− The gamma table can support this, thus avoiding redesigning the existing graphics.

Input Color

(address of value

in table)

Color output to

the display panel

0 0

1 1

2 2

3 3

4 4


0xFE 0xFE

0xFF 0xFF

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External Use 59

Gamma correction

• Another use for gamma correction is in the case where there are fewer than 8 bits of information per color.

• It is common for panels to use 18 bits of color (6 bits each for RGB).

• In this case, it is possible to use the gamma correction to adjust the hardware connection.

• In the table values the raw 8-bit values are adjusted to appear as 6-bit values (2 lsbs are ignored).

Input Color

(address of value

in table)

Color output to

the display panel

0 0

1 0

2 0

3 0

4 1

5 1

6 1


0xFE 0x3F

0xFF 0x3F

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External Use 60

Gamma Correction – colors inverted!

Original graphic with no

gamma correction Gamma correction enabled:

All colors intensity inverted

High R intensity +

low G & B.

Becomes low R,

high G & B = cyan

Low R, G & B.

Becomes high R, G

& B = white

High B intensity +

low R & G.

Becomes low B,

high R & G = yellow

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External Use 61

Gamma Correction – colors inverted!

void InitGamma()

{

uint16_t i;

uint32_t* gammaR, *gammaG, *gammaB;

gammaR = (uint32_t*) DCU0_GAMMARED;

gammaG = (uint32_t*) DCU0_GAMMAGREEN;

gammaB = (uint32_t*) DCU0_GAMMABLUE;

/* Invert gamma */

for (i=0;i<0x100;i++)

{

reg32_write(gammaR+i,~i);

reg32_write(gammaG+i,~i);

reg32_write(gammaB+i,~i);

}

}

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External Use 62

Hardware Cursor

• Operates in 1bpp mode

− Bits in 0 are transparent

− Bits in 1 are fully opaque in color defined by a default HWC register

• Includes its own RAM area

• Automatic blink option

− EN_BLINK

− HWC_BLINK_ON.- Number of refresh cycles is visible

− HWC_BLINK_OFF.- Number of refresh cycles is NOT visible

• Cursor not visible in case invalid configuration

− HWC_ERR flag is set

• Cursor RAM may be written at any time, even during vertical

blanking period, or if DCU is not enabled.

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External Use 63

Hardware Cursor

/* Cursor */

reg32_write(DCU0_CTRLDESCCURSOR1,0x00200020); /* 32 x 32 */

reg32_write(DCU0_CTRLDESCCURSOR2,0x00260050); /* (80,38) */

reg32_write(DCU0_CTRLDESCCURSOR3,0x00FFFFFF); /* Cursor color */

reg32_write(DCU0_CTRLDESCCURSOR4,0x00200010); /* Cursor blink rate 16 on, 32 off*/

cursor = (uint32_t*) DCU0_CURSOR;

for (i=0;i<16;i++)

{

reg32_write(cursor+i, Cur32x32H[i]); /* Copy cursor */

reg32_write(cursor+(31-i), Cur32x32H[i]); /* Copy cursor */

}

reg32setbit(DCU0_CTRLDESCCURSOR3,DCU_CTRLDESCCURSOR3_CUR_EN_SHIFT); /* Enable cursor */

reg32clrbit(DCU0_CTRLDESCCURSOR4,DCU_CTRLDESCCURSOR4_EN_BLINK(1)); /* Enable blinking */

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External Use 64

CLUT/Tile RAM

• The CLUT/Tile RAM is mapped in the DCU4 32K memory space

• Color information is stored as aligned 32-bit words 0xAARRGGBB

• Can be used to store either CLUT or graphics for use as a tile on a layer.

• The content of the RAM at a specific address is defined by the control descriptor of a layer.

• Example: Area A is used by layer 1 as a CLUT for its 4 bpp graphic. Area B is use by layer 5 as a store for its tile graphic. Area C is used by layers 2, 7, and 9 as a CLUT for their 8 bpp graphics.

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External Use 65

Special DDR mode

• Special configuration that optimizes the use of an SDRAM memory

by the DCU4 by forcing the DCU4 to fetch data in optimal chunks

• Only available in the six highest priority layers (0:5)

• Enabled by DCU_MODE[DDR_MODE] bit

• DCU will fetch data in 32-byte chunks optimizing the SDRAM

throughput

• This mode only permits operation in four-layer blend mode,

therefore, the DCU_MODE[BLEND_ITER] field must be set to 4

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External Use 66

Run Length Encoding (RLE) Mode

• Only available if Special DDR is enabled

• Up to 6 layers

• Support for:

− 8bpp

− 16bpp (RGB565, ARGB1555, ARGB4444, APAL8)

− 24bpp

− 32bpp (BGRA8888)

• RLE_ERR is set if more than the number of RLE layers have the

RLE_EN

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External Use 67

Run Length Encoding (RLE) Mode

• Incoming data stream from compressed image (8bpp format):

• 85,27,83,03,04,27,44,01,B2,1C,87,C9

27,27,27,27,27,27,03,03,03,03,27,44,01,B2,1C,C9,C9,C9,C9,C9,C9,C9,C9

CMD[7]=1

Count=5

Pixel Value = 27

Repeat 27, 6 times

CMD[7]=1

Count=3

Pixel Value = 03

Repeat 03, 4 times

CMD[7]=0

Count=4

Pixels= 27,44,01,B2,1C

Copy 5 raw pixel to output

CMD[7]=1

Count=7

Pixel Value = C9

Repeat 09, 8 times

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External Use 68

DCU FIFOs and DMA Activity

• DCU uses a dedicated DMA

• Memory access is shared between system DMA and CPU

• In/Out FIFOs to temporarily store data until required, reducing the pixel starvation possibility

• Input FIFO buffer of 256 x 64 bit. Max DMA Burst is 16 pixels. − Thresholds: INP_BUF_Pm_HI.- Upper threshold for DCU pauses fetching data

• Pm_FIFO_HI_FLAG. Upper Threshold reach

INP_BUF_Pm_LO.- Lower threshold

• m_FIFO_LO_FLAG.- Less data than low threshold. No data available, reaching EOF or No need for pixels

− INT_STATUS can indentify which layer/graphic was too slow to be loaded

• Output FIFO - 128 pixels in size − Thresholds: OUT_BUF_HIGH.- Upper threshold. Processing should stop to let DCU use some values

(Sufficient data)

OUT_BUF_LOW.- Lower threshold. If reached UNDRUN flag/situation is set

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External Use 69

Error detection

• Error flags are asserted when:

− Errors in configuration

− Attempts to modify configuration at invalid point during panel refresh

period

− Unable to access the required source data

• Errors are stored in:

− PARR_ERR_STATUS1, 2, 3

• Flags Ln indicates a error in the n-th layer configuration

− Invalid tile mode size

− Horizontal dimension out of range

• Reads of CLUT/Tile RAM when LCD panel is being updated, and

do NOT return its content

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External Use 70

Safety Mode

• Requirement for Safety Level Standards like SIL2 and ASILB

• Highest Priority Layer 0 and Layer 1 are Safety Layers

• In Safety Mode:

− Croma-keying is enabled

− Alpha blending is ALWAYS IGNORED

− Layer format of 32bpp NOT Allowed (If used, then layer is disabled)

• Calculates 2 signatures:

− Pixel value CRC

− Position CRC

• Completed signature can be compared against a pre-calculated value

− CRC_READY is asserted at end of any frame

− CRC_OVERFLOW Interrupt .- If CRC_READY is not completed within one

frame time period

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External Use 71

Safety Mode

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External Use 72

Safety Mode

• Pixels in selected area are TAGGED

• ONLY Pixels removed by Croma-Keying are not TAGGED

• ONLY Tagged pixels are included in the calculation for the CRC

TM

External Use 73

Parallel Data Interface

• Requires the incoming video stream to match the resolution and timing at which LCD is driven

• Incoming stream must NOT be interlaced

• PDI in slave mode

− Ignores pixel information (External BG)

− Only passes the timing info to DCU to sync with it

• PDI is compatible with various input formats:

− Normal Mode

− Narrow Mode

− External Sync

− Internal Sync

TM

External Use 74

Summary (DCU features)

• 64 graphics layers, a default background color layer and a cursor layer with integrated blinking option

• Blending of each pixel using up to 6 source layers dependent on size of panel

• Programmable panel size, up to a maximum of XGA (1024x768) and a typical operating configuration of SVGA (800 x 600)

• Gamma correction with 8-bit resolution on each color component

• Safety mode for tagging pixels on highest priority layers

• Dedicated memory blocks to store a cursor and Color Look Up Tables (CLUTs)

• Temporal Dithering

TM

External Use 75

Summary (DCU features)

• Each graphic layer has the following attributes:

− Can be placed with one pixel resolution in either axis

− Can also be placed in negative X and Y directions

− Supports multiple color-encoding formats

− Alpha blending with 8-bit resolution

− Chroma-key blending for anti-mask encoding

− Multiple combined alpha and chroma-key blending modes

− Transparency modes for anti-aliased text and graphics

− Luminance mode for highlighting content

− Tile mode for efficient creation of textured background content

− Support for Run Length Encoding (RLE) compression

− Optimized mode for use with DDR memory

TM

© 2014 Freescale Semiconductor, Inc. | External Use

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Documents

2D-Animation and Composition Engine (ACE) and Graphics … · 2016. 3. 12. · TM External Use 1 Session Introduction •This session gives an introduction of the Display Control