ST7577 datasheet(16/48 Pages) SITRONIX

16 / 48 page

ST7577

Ver 1.0a

16/48

2008/02/14

START LINE ADDRESS CIRCUIT

This circuit assigns DDRAM a line address that is scanned first at the beginning of each frame. By setting Start Line

Address repeatedly, the display pattern looks like scrolling vertically in the screen without changing the contents of DDRAM

(refer to Figure 11). When setting the Start Line Address (with

“Set Start Line” instruction), the data of the same specified

line address in DDRAM are transferred to the Display Data Latch Circuit at the beginning of each frame.

ADDRESSING

ST7577 will automatically increases the address when sequential access. This feature allows MPU to access the display

data in DDRAM continuously without setting the address before each access.

In horizontal addressing mode, the X address is automatically increased by 1 after each byte access (refer to Figure 8).

After the last X address (X=131), X address wraps around to 0 and Y address increases to the next page. After the very last

address (X=131, Y=4), the address pointers wrap around to the original address (X=0, Y=0).

In vertical addressing mode, the Y address is automatically increased by 1 after each byte access (refer to Figure 9). After

the last Y address (Y=4), Y address wraps around to 0 and X address increases to the next column. After the very last

address (X=131, Y=4), the address pointers wrap around to the original address (X=0, Y=0).

Figure 8

Addressing Mode: Horizontal (V=0)

Figure 9

Addressing Mode: Vertical (V=1)

ST7577 Datasheet(PDF) 16 Page - Sitronix Technology Co., Ltd.