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MTV118 Revision 2.0 01/01/1999

MTV118

MYSON

TECHNOLOGY

The vertical display center for a full-screen display may be figured out according to the information of

the vertical starting position register (VERTD) and VFLB input. The vertical delay starting from the lead-

ing edge of VFLB is calculated using the following equation:

Vertical delay time = ( VERTD * 4 + 1 ) * H

Where H = 1 horizontal line display time

Note: “v”means the nth line in the character would be repeated once, while “-” means the nth line in the

character would not be repeated.

3.4 Horizontal Display Control

The horizontal display control is used to generate control timing for a horizontal display based on dou-

ble character width bit (CWS), horizontal positioning register (HORD) and HFLB input. A horizontal dis-

play line includes 360 dots for 30 display characters and the remaining dots for a blank region. The

horizontal delay starting from the HFLB leading edge is calculated using the following equation:

Horizontal delay time = ( HORD * 6 + 49) * P

Where P = 1 XIN pixel display time

3.5 Display & Row Control Registers

The internal RAM contains display and row control registers. The display registers have 450 locations

which are allocated between row 0/column 0 and row 14/column 29 as shown in Figure 4. Each display

register has its corresponding character address on the address byte, and 1 blink bit and its corre-

sponding color bits on attribute bytes. The row control register is allocated at column 30 for row 0 to row

14; it is used to set character size for each respective row. If the double width character (CWS) is cho-

TABLE 2. Repeat Line Weight of Character

CH6-CH0

Repeat Line Weight

CH6,CH5=11

+18*3

CH6,CH5=10

+18*2

CH6,CH5=0x

+18

CH4=1

+16

CH3=1

+8

CH2=1

+4

CH1=1

+2

CH0=1

+1

TABLE 3. Repeat Line Number of Character

Repeater Line

Weight

Repeat Line #

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

+1

-

-

-

-

-

-

-

-

v

-

-

-

-

-

-

-

-

-

+2

-

-

-

-

v

-

-

-

-

-

-

-

v

-

-

-

-

-

+4

-

-

v

-

-

-

v

-

-

-

v

-

-

-

v

-

-

-

+8

-

v

-

v

-

v

-

v

-

v

-

v

-

v

-

v

-

-

+16

-

v

v

v

v

v

v

v

v

v

v

v

v

v

v

v

v

-

+17

v

v

v

v

v

v

v

v

v

v

v

v

v

v

v

v

v

-

+18

v

v

v

v

v

v

v

v

v

v

v

v

v

v

v

v

v

v