In text display modes, the video hardware causes the cursor to blink, and the blink cannot be disabled. In graphics modes, the hardware cursor is not available.Selects the starting and ending lines for the blinking hardware cursor in text display modes.
Call with:
AH = 01H
CH bits 0—4 = starting line for cursor
CL bits 0—4 = ending line for cursor
Returns:
Nothing
Notes:
In text display modes, the video hardware causes the cursor to blink, and the blink cannot be disabled. In graphics modes, the hardware cursor is not available.
The default values set by the ROM BIOS are:
Display Start End monochrome mode 07H 11 12 text modes 00H—03H 6 7
On the EGA, MCGA, and VGA in text modes 00H—03H, the ROM BIOS accepts cursor start and end values as though the character cell were 8 by 8 and remaps the values as appropriate for the true character cell dimensions. This mapping is called cursor emulation.
You can turn off the cursor in several ways. On the MDA, CGA, and VGA, setting register CH = 20H causes the cursor to disappear. Techniques that involve setting illegal starting and ending lines for the current display mode are unreliable. An alternative is to position the cursor to a nondisplayable address, such as (x,y)=(0,25).