Specifications

AH = 09h write character and attribute at cursor position

AL = character

BL = attributes

BH = screen page number

CX = number of characters/attributes to write

AH = 0Ah write character at cursor position

BH = screen page number

CX = number of characters to write

AL = characters

AH = 0Bh set color palette

BH = color palette

BL = color values used with color palette

AH = 0Ch set single pixel

AL = color value for pixel

BH = screen page number (if more than one page)

DX = line of pixel

CX = row of pixel

AH = 0Dh read single pixel

BH = screen page number (if more than one page)

DX = line of pixel

CX = row of pixel

AL = color value of pixel

AH = 0Eh write character at cursor position (TTY Write)

AL = character

BL = foreground color in graphics mode

BH = screen page number (if more than one page)

AH = 0Fh read current screen status

AL = character

AH = current screen page number

BH = current screen page number

AX = 1000h set a palette register

BL = number or palette register

BH = color for palette register

AX = 1001h set overscan register

BH = color value for overscan register

AX = 1002 h set all palette registers and overscan register

ES:DX = address for 17 byte for the registers