Functional Description
1392
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
LCD Controller
Table 20-5. Number of Colors and Shades of Gray Available on Screen
Passive Mode (LCDTFT = 0)
Active Mode (LDCTFT = 1)
Color Only (LCDBW = 0)
Bits
Monochrome (LCDBW = 1)
Color (LDCBW = 0)
1
2 palette entries to select within 15
grayscales
2 palette entries to select within 3375
possible colors
2 palette entries to select within 4096
possible colors
2
4 palette entries to select within 15
grayscales
4 palette entries to select within 3375
possible colors
4 palette entries to select within 4096
possible colors
4
16 palette entries to select within 15
grayscales
16 palette entries to select within
3375 possible colors
16 palette entries to select within
4096 possible colors
8
Not relevant because it would consist
in 256 palette entries to select within
15 grayscales, but exists anyways
256 palette entries to select within
3375 possible colors
256 palette entries to select within
4096 possible colors
12
–
3375 possible colors
4096 possible colors
16
–
3375 possible colors (STN_565 = 1)
Up to 65536 possible colors
24
–
–
Up to 16.7 million colors
20.3.12 Output Format
The following section describes the output format for both passive and active LCD modes.
20.3.12.1 Passive (STN) Mode
As shown in
, the pixel data stored in frame buffers go through palette (if applicable) and
grayscaler and serializer before reaching the output FIFO. As a result, it is likely that the data fed to the
output FIFO is numerically different from the data in the frame buffers. (However, they represent the same
color or grayscale.)
The output FIFO formats the received data according to display modes.
, shows the actual
data output on the external pins.
20.3.12.2 Active (TFT) Mode
As shown in
, the grayscaler and serializer and output FIFO are bypassed in active (TFT)
mode. Namely, at each pixel clock, one pixel data (16 bits) is output to the external LCD.