3.15. LCD Interface

Pin Signal Description type I/O
117-128, 130-141 LCD_D[0-23] LCD Data    
143 HSYNC Line Pulse or HSync    
144 VSYNC rame Sync or VSync—This signal also serves as the clock signal output for gate; driver (dedicated signal SPS for Sharp panel HR-TFT)    
145 OE_ACD Alternate Crystal Direction/Output Enable    
146 LSCLK Shift Clock    

The LCD Controller of the i.MX processors provides display data for external greyscale or color LCD panels. The LCD Controller is capable of supporting black-and-white, greyscale, passive-matrix color (passive color or CSTN), and active-matrix color (active color or TFT) LCD panels.

The TX LCD Interface defines a generic 24 bit Panel Interface LCD_D[23..0]. The TFT color channel assignments are shown in the table below:

LCD_D 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
TX28 TX51 TX53 TX6 LD 23 LD 22 LD 21 LD 20 LD 19 LD 18 LD 17 LD 16 LD 15 LD 14 LD 13 LD 12 LD 11 LD 10 LD 9 LD 8 LD 7 LD 6 LD 5 LD 4 LD 3 LD 2 LD 1 LD 0
TX48 LD 4 LD 3 LD 2 LD 1 LD 0 LD 16 LD 18 LD 21 LD 10 LD 9 LD 8 LD 7 LD 6 LD 5 LD 19 LD 22 LD 15 LD 14 LD 13 LD 12 LD 11 LD 17 LD 20 LD 23
TX25 TX27 LD 17 LD 16 LD 15 LD 14 LD 13 LD 12 GP IO GP IO LD 11 LD 10 LD 9 LD 8 LD 7 LD 6 GP IO GP IO LD 5 LD 4 LD 3 LD 2 LD 1 LD 0 GP IO GP IO
24bpp R7 R6 R5 R4 R3 R2 R1 R0 G7 G6 G5 G4 G3 G2 G1 G0 B7 B6 B5 B4 B3 B2 B1 B0
18bpp R5 R4 R3 R2 R1 R0     G5 G4 G3 G2 G1 G0     B5 B4 B3 B2 B1 B0    
16bpp [1] R4 R3 R2 R1 R0       G5 G4 G3 G2 G1 G0     B4 B3 B2 B1 B0      
12bpp R3 R2 R1 R0         G3 G2 G1 G0         B3 B2 B1 B0        

With this assignment the two module types – 18bpp like the TX25 and TX27 and 24bpp like the TX51 – can be used on the same carrier board without any change. On 18bpp modules the unused bits are always connected to General Purpose IOs to be able to drive these to a defined level.

Module Remark [1]
TX48 The blue and red color assignments to the LCD data pins are reversed when operating in RGB888 (24bpp) mode compared to RGB565 (16bpp) mode. Using the LCD Controller with this connection scheme limits the use of RGB565 mode. Any data generated for the RGB565 mode requires the red and blue color data values be swapped in order to display the correct color.
[1](1, 2) AM335x ARM® Cortex-A8 Microprocessors (MPUs) Silicon Errata