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MTV018 Revision 4.0 10/21/1999

MTV018

MYSON

TECHNOLOGY

3.8 Character ROM

The character ROM contains 248 built-in characters and symbols from address 0 to 247. Each character and

symbol consists of 12x18 dots matrix. The detail pattern structures for each character and symbols are shown

in “CHARACTERS AND SYMBOLS PATTERN” on page 16.

3.9 Luminance & border generator

There are 2 shift registers included in the design which can shift out of luminance and border dots to color

encoder. The bordering and shadowing feature is configured in this block. For bordering effect, the character

will be enveloped with blackedge on four sides. For shadowing effect, the character is enveloped with

blackedge for right and bottom sides only.

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.

CCS - When a window is overlapping with the character, character color 2 should be chosen while this bit is

set to 1. Otherwise color 1 is selected.

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

2. Frame control registers,

ROW 15

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

CCS

-

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