Lucent Technologies MN102F85K User Manual

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Set CHP, CVP, GHP, and GVP 

for every line in the VRAM. If 

you do not, a software 
processing error may occur.

1.

The lead data for each line must be the color control code (COL) or the char-
acter code (CC). Never place the horizontal position (CHP), vertical position 

(CVP), or repeat (CCB) codes at the beginning of a line. (If the lead data is 
CC, with no COL specification, the character will be text palette color 1, and 

the background will be color 2.)

2.

Place each line’s horizontal and vertical position data (CHP and CVP), in 

that order, at the end of the preceding line.

3.

Insert the color control code (COL) before the character code (CC). You do 

not need to meet condition 3 in the closed-caption mode, since COL can 
carry over in that mode.

4.

A character code (CC) must immediately precede a repeat character/blank 
code (CCB), and a color control code (COL) or character code (CC) must 

follow it.

5.

To indicate the last line of a display, make the CHP and CVP values for the 

last line smaller than those in the currently displayed line. In addition, write 
a 1 to the last line flag of the text layer (CLAST).

6.

Two text lines (but no more) can overlap on the screen. The lower line takes 
priority, appearing to lie on top of the higher line.

7.

If the horizontal sync signal is asserted while the microcontroller is access-
ing CHP and CVP, that line and the next line may not display properly. (For 

details, see section 7.10.4, “Setting Up the OSD Display Position,” on page 
189.)

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1.

Place each line’s horizontal and vertical position data (GHP and GVP), in 
that order, at the end of the preceding line. Do not place GHP and GVP at the 

start of a line.

2.

To indicate the last line of a display, make the GHP and GVP values for the 

last line smaller than those in the currently displayed line. In addition, write 
a 1 to the last line flag of the graphics layer (GLAST).

3.

Two graphic lines (but no more) can overlap on the screen. The lower line 
takes priority, appearing to lie on top of the higher line.

4.

If the horizontal sync signal is asserted while the microcontroller is access-
ing GHP and GVP, that line and the next line may not display properly. (For 

details, see section 7.10.4, “Setting Up the OSD Display Position,” on page 
189.)