Epson Research and Development

Page 19

Vancouver Design Center

 

 

 

4 bpp color

When the S1D13705 is configured for 4 bpp color mode, the displayed colors are selected from the first sixteen entries of the Look-Up Table. The LUT entries may be set to any of the 4096 possible colors.

Each byte in the display buffer contains two adjacent pixels. If a nibble has a value of “0000” then the color in LUT index 0 is displayed. A nibble value of “0001” results in the color in LUT index 1 being displayed. The pattern continues to the nibble pattern of “1111” which results in the sixteenth color of the Look-Up Table being displayed.

The following table shows the example values for 4 bit-per-pixel display mode. These colors simulate the colors used by the sixteen color modes of a VGA.

Table 4-3: Suggested LUT Values to Simulate VGA Default 16 Color Palette

Index

Red

Green

Blue

 

 

 

 

00

00

00

00

 

 

 

 

01

00

00

A0

 

 

 

 

02

00

A0

00

 

 

 

 

03

00

A0

A0

 

 

 

 

04

A0

00

00

 

 

 

 

05

A0

00

A0

 

 

 

 

06

A0

A0

00

 

 

 

 

07

A0

A0

A0

 

 

 

 

08

00

00

00

 

 

 

 

09

00

00

F0

 

 

 

 

0A

00

F0

00

 

 

 

 

0B

00

F0

F0

 

 

 

 

0C

F0

00

00

 

 

 

 

0D

F0

00

F0

 

 

 

 

0E

F0

F0

00

 

 

 

 

0F

F0

F0

F0

 

 

 

 

10

00

00

00

...

00

00

00

FF

00

00

00

 

 

 

 

indicates unused entries

Programming Notes and Examples

S1D13705

Issue Date: 02/01/22

X27A-G-002-03

Page 113
Image 113
Epson S1D13705 technical manual Bpp color