VII LCD CONTROLLER BLOCK: LCD CONTROLLER

Display Modes

The number of gray levels in grayscale display and the number of colors in color display are determined by the number of bits representing each pixel (bpp = bits per pixel). Write this bpp value to BPP[1:0] (D[7:6])/LCDC mode register 1 (0x39FFE2) in order to set the display mode (number of gray levels/colors displayed).

 

Table 2.5

Specification of Display Modes

 

LDCOLOR

BPP1

 

BPP0

Display mode

0

0

 

0

2 gray levels

1 bit-per-pixel

 

 

 

1

4 gray levels

2 bit-per-pixel

 

1

 

0

16 gray levels

4 bit-per-pixel

 

 

 

1

Reserved

1

0

 

0

2 colors

1 bit-per-pixel

 

 

 

1

4 colors

2 bit-per-pixel

 

1

 

0

16 colors

4 bit-per-pixel

 

 

 

1

256 colors

8 bit-per-pixel

(1) 1-bpp (2-gray-level/2-color) mode

One pixel is represented by 1 bit, displayed in two gray levels or two colors.

For monochrome LCD panels, 2-gray-level display can be obtained by assigning two gray levels from among the 16 gray levels available, including black and white, to two entries in the green look-up table (described later) (one each for bits = "0" and "1").

For color LCD panels, two colors from among the 4,096 colors available can be set in advance using two entries for pixel data "0" and "1" in each of the red, green, and blue look-up tables.

Data for eight consecutive pixels is stored as one byte in the display memory.

 

(bit 7)

 

 

Display memory

 

(bit 0)

 

 

 

 

 

LCD panel

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

P0

P1

P2

P3

P4

P5

P6

P7

P8

 

Byte 1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A8

A9

A10

A11

A12

A13

A14

A15

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Byte 0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A0

A1

A2

A3

A4

A5

A6

 

A7

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Pn = (An)

Figure 2.4 Data Format in 1-bpp Mode

(2) 2-bpp (4-gray-level/4-color) mode

One pixel is represented by 2 bits, displayed in four gray levels or four colors.

For monochrome LCD panels, 4-gray-level display can be obtained by assigning four gray levels from among the 16 gray levels available, including black and white, to four entries in the green look-up table (one each for bits = "00" to "11").

For color LCD panels, four colors from among the 4,096 colors available can be set in advance using four entries for pixel data "00" to "11" in each of the red, green, and blue look-up tables.

Data for four consecutive pixels is stored as one byte in the display memory.

 

(bit 7)

 

Display memory

 

(bit 0)

 

 

 

 

 

LCD panel

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

P0

P1

P2

P3

P4

P5

P6

P7

 

Byte 1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A4

 

B4

A5

B5

A6

B6

A7

 

B7

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Byte 0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A0

 

B0

A1

B1

A2

B2

A3

 

B3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Pn = (An, Bn)

Figure 2.5 Data Format in 2-bpp Mode

A-1

B-VII

LCDC

S1C33L03 FUNCTION PART

EPSON

B-VII-2-9