Samsung 8-Bit CMOS Microcontroller, S3C9228/P9228 user manual LCD RAM Address Area

S3C9228/P9228 LCD CONTROLLER/DRIVER

LCD RAM ADDRESS AREA

RAM addresses of page 1 are used as LCD data memory. When the bit value of a display segment is "1", the LCD display is turned on; when the bit value is "0", the display is turned off.

Display RAM data are sent out through segment pins SEG0–SEG19 using a direct memory access (DMA) method that is synchronized with the fLCD signal. RAM addresses in this location that are not used for LCD

display can be allocated to general-purpose use.

SEG0 SEG1 SEG2 SEG3 SEG17 SEG18 SEG19

COM0 b0 COM1 b1 COM2 b2 COM3 b3 COM4 b4 COM5 b5 COM6 b6 COM7 b7

100H 101H 102H 103H

111H 112H 113H

Figure 13-3. LCD Display Data RAM Organization

Table 13-1. Common and Segment Pins per Duty Cycle

Duty	Common Pins	Segment Pins	Dot Number
1/8	COM0–COM7	16 pins	128 dots
1/4	COM0–COM3	20 pins	80 dots
1/3	COM0–COM2	20 pins	60 dots

13-3