Specifications

Color LCD Controller (CLCDC)

Movement

The following descriptions assume that both the screen and cursor origins are at the top

left of the visible screen (the first visible pixel scanned each frame). Each pixel

coordinate is assumed to be the top left corner of the pixel as shown in Figure 5-4.

Figure 5-4 Hardware cursor movement

The ClcdCrsrXY Register controls the cursor position on the cursor overlay. This

provides separate fields for X and Y ordinates.

The ClcdCrsrConfig Register (see Cursor Configuration Register on page 5-20)

provides a FrameSync bit controlling the visible behavior of the cursor.

With FrameSync inactive, the cursor responds immediately to any change in the

programmed ClcdCrsrXY value. Some transient smearing effects are likely to be visible

if the cursor is moved across the LCD scan line.

With FrameSync active, the cursor only updates its position after a vertical

synchronization has occurred. This provides clean cursor movement, but the cursor

position only updates once a frame

The ClcdCrsrXY Register (see Cursor XY Position Register on page 5-21) is

programmed with positive binary values that enable the cursor image to be located

anywhere on the visible screen image. The cursor image is clipped automatically at the

screen limits when it extends beyond the screen image to the right or bottom (see X1,Y1

in Figure 5-5 on page 5-10). The checked pattern shows the visible portion of the cursor.

ClcdCrsrXY(X)

ClcdCrsrXY(Y)

(0,0)