VII LCD CONTROLLER BLOCK: LCD CONTROLLER

Clock

The LCD controller uses the BCU clock as the source clock for its pixel clock PCLK and display memory clock MCLK. The maximum clock frequency that can be supplied to the LCD controller is 25 MHz. The BCU clock divide ratios can be set using the LCLKSEL[2:0] (D[2:0])/FIFO control register (0x39FFF4), as shown in Table 2.3 below.

 

 

 

 

To CPU

 

 

 

 

 

 

 

 

Bus clock

#X2SPD pin

 

 

 

 

 

 

 

LCLKSEL[2:0]

 

 

 

 

 

 

 

 

 

 

 

CLG

BCU

1/1

 

 

 

 

 

 

 

 

 

 

 

 

 

BCU_CLK

1/2

 

LCDC clock (PCLK, MCLK)

CPU_CLK

 

 

1/1 or 1/2

 

 

 

 

 

 

 

 

 

 

1/3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1/4

 

 

Figure 2.3 LCDC Clocks

Table 2.3 Selection of LCDC Clocks

LCLKSEL2

LCLKSEL1

LCLKSEL0

LCDC clock

0

0

0

Turned off

0

0

1

Turned off

0

1

0

Turned off

0

1

1

Reserved (not allowed)

1

0

0

BCU_CLK

1

0

1

BCU_CLK/2

1

1

0

BCU_CLK/3

1

1

1

BCU_CLK/4

A-1

B-VII

LCDC

S1C33L03 FUNCTION PART

EPSON

B-VII-2-7