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MTV021 Revision 5.0 6/29/1999

MTV021

MYSON

TECHNOLOGY

3.10 Window and frame control

The display frame position is completely controlled by the contents of VERTD and HORD. The window size

and position control are specified in column 0 to 11 on row 15 of memory map, as shown in Figure 4. Window

1 has the highest priority, and window 4 is the least, when two windows are overlapping. More detailed infor-

mation is described as follows:

1. Window control registers,

ROW 15

START(END) ADDR - These addresses are used to specify the window size. It should be noted that when

the start address is greater than the end address, the window will be disabled.

WEN - Enable the window display.

WSHD - Enable shadowing on the window.

R, G, B - Specify the color of the relative background window.

2. Frame control registers,

ROW 15

VERTD - Specify the starting position for vertical display. The total steps are 256, and the increment of each

step is 4 Horizontal display lines. The initial value is 4 after power up.

HORD - Define the starting position for horizontal display. The total steps are 256, and the increment of each

step is 6 dots. The initial value is 15 after power up.

CH6-CH0 - Define the character vertical height, the height is programmable from 18 to 71 lines. The character

vertical height is at least 18 lines if the contents of CH6-CH0 is less than 18. For example, when

the contents is " 2 ", the character vertical height is regarded as equal to 20 lines. And if the con-

Column

0,3,6,OR 9

b7

b6

b5

b4

b3

b2

b1

b0

ROW START ADDR

MSB

LSB

ROW END ADDR

MSB

LSB

Column

1,4,7,OR 10

b7

b6

b5

b4

b3

b2

b1

b0

COL START ADDR

MSB

LSB

WEN

-

WSHD

Column

2,5,8,OR 11

b7

b6

b5

b4

b3

b2

b1

b0

COL END ADDR

MSB

LSB

R

G

B

Column 12

b7

b6

b5

b4

b3

b2

b1

b0

VERTD

MSB

LSB

Column 13

b7

b6

b5

b4

b3

b2

b1

b0

HORD

MSB

LSB

Column 14

b7

b6

b5

b4

b3

b2

b1

b0

-

CH6

CH5

CH4

CH3

CH2

CH1

CH0