STV2050A datasheet(37/83 Pages) STMICROELECTRONICS

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STV2050A - VIDEO PATTERN GENERATOR

7.4 BORDER LINES

Convergence adjustments at the edges of the screen are more difficult because the grid points

which are involved are not visible. Therefore, additional horizontal and vertical border lines are

implemented for making adjustments at these positions.

7.4.1 Border Lines: Left / Right

The horizontal position of the border lines is programmable by the BPH[5:0] bits in the D7 reg-

ister.

Figure 19. Border Lines

Note: The BPH bit must be smaller than the HGD bit.

7.4.2 Border Lines: Bottom / Top

The vertical position of the border lines depends on bits BPV[5:0] in register D7.

00h

The position of the border lines is identical to the vertical grid lines at horizon-

tal grid positions 1 and 15

01h to 1Fh

The border lines move toward the centre of the screen in increments of BPH

clock cycles. The range for the shift of the border line is one horizontal grid

distance.

00h

The position of the horizontal border lines is identical to the horizontal grid lines at posi-

tions 0 and 12.

01h to 1Fh

The horizontal border lines move toward the centre of the screen by BPV video lines.

The allowed range for the BPV value is one vertical grid distance.

Grid

BPH

Borderlines

STV2050A Datasheet(PDF) 37 Page - STMicroelectronics