Intel PXA250 and PXA210 manual Active TFT Displays, LCD Display Controller

Models: PXA250 and PXA210

1 190
Download 190 pages 11.36 Kb
Page 49
Image 49
Figure 3-5. Passive Color Dual Panel Displays Typical Connection

LCD Display Controller

Figure 3-5. Passive Color Dual Panel Displays Typical Connection

PXA250 Processor

L_DD0

DU_0

L_DD1

DU_1

L_DD2

DU_2

L_DD3

DU_3

L_DD4

DU_4

L_DD5 - Top left Blue for upper panel

DU_5

L_DD6 - Top left Green for upper panel

DU_6

L_DD7 - Top left Red for upper panel

DU_7

L_PCLK

Pixel_Clock

L_LCLK

Line_Clock

L_FCLK

Frame_Clock

L_BIAS

Bias

L_DD8

DL_0

L_DD9

DL_1

L_DD10

DL_2

L_DD11

DL_3

L_DD12

DL_4

L_DD13 - Top left Blue for lower panel

DL_5

L_DD14 - Top left Green for lower panel

DL_6

L_DD15 - Top left Red for lower panel

DL_7

 

 

 

 

Upper Panel

LCD Display

Lower Panel

3.3Active (TFT) Displays

Because data is sent to the panel as raw 16-bit pixel data, active displays require16 data pins in order to transfer the pixel data from the controller. All 16 data lines are also required to drive one pixel value. The 16 bits of data describe the intensity level of the red, green and blue for each pixel. Typically, this is formatted as 5 bits for red, 6 bits for green and 5 bits for blue, but this can vary by display and is controlled by the software writing to the frame buffer. Refer to the display datasheet to ensure that the correct the PXA250 applications processor LCD data lines are connected to the correct LCD panel data lines.

Many active displays actually have more than 16 data lines - usually 18 (6 of each color). For these panels it is recommended that the most significant lines of the panel lines are connected to the data lines from the PXA250 applications processor. This maintains the panel’s full range of colors but increases the granularity of the color spectrum with an insufficient number of data lines. All unused panel data lines can be tied either high or low. Other options include tying the LSB of red and blue to the next bit, R1 or B1.

For active displays, connect the pins described in Table 3-3between the PXA250 applications processor and the LCD panel.

PXA250 and PXA210 Applications Processor Design Guide

3-5

Page 49
Image 49
Intel manual Active TFT Displays, LCD Display Controller, PXA250 and PXA210 Applications Processor Design Guide