assembly - INT 10, 13h 如何与属性一起使用？

Question

嘿，我试图理解 INT 10h, 13h (19)，它用 BIOS 中断 10 和 13h 写入字符串。我找到了下面有关放入不同寄存器的不同标志的信息。我仍然不明白的一件事是 BL 中应该包含什么，如果我只是想用这个函数编写一个字符串，BL 中应该包含什么作为属性？现在它写出奇怪的闪烁符号，没有意义。预先谢谢您

Writes a string of characters with specified attributes to any display
page.

   On entry:      AH         13h
                  AL         Subservice (0-3)
                  BH         Display page number
                  BL         Attribute (Subservices 0 and 1)
                  CX         Length of string
                  DH         Row position where string is to be written
                  DL         Column position where string is to be written
                  ES:BP      Pointer to string to write

   Returns:       None

   Notes:         This service is available only for XTs dated 1/19/86
                  and later, ATs, EGAs, and PC Convertibles.

                  The service has four subservices, as follows:

                  AL=00h: Assign all characters the attribute in BL;
                  do not update cursor
                  AL=01h: Assign all characters the attribute in BL;
                  update cursor
                  AL=02h: Use attributes in string; do not update
                  cursor
                  AL=03h: Use attributes in string; update cursor

                  In Subservices 0 and 1, all characters in the string
                  are written to the screen with the same attribute--
                  the attribute specified in BL.

                  In Subservices 2 and 3, the attribute byte for each
                  character is found in the string itself. The string
                  itself consists of a character followed by its
                  attribute, another character followed by its
                  attribute, and so on. The string is copied directly
                  to the video buffer as is.

                  In Subservices 0 and 2, the cursor position is not
                  updated after the string is written.

                  In Subservices 1 and 3, the cursor is moved to the
                  first position following the last character in the
                  string.

                  Like Service 0Eh, Service 13h responds appropriately
                  to ASCII 07h (bell), 08h (backspace), 10h (line
                  feed), and 0Dh (carriage return). All other
                  characters are printed.

Answer 1

对于 int 10h，BL 寄存器用于颜色属性。

除非您正在处理 CGA，其中 BL 值是调色板编号，BL 值是表示前景色的数字(4 位 - 低部分) )和背景颜色(4 位 - 高位部分)。

例如，如果您想要蓝色 (0x01) 背景和红色 (0x04) 文本颜色，则需要将 0x14 放入 BL 寄存器中 -二进制文件为 00010100。

      0001             0100
|_ Background _| |_ Foreground _|

颜色通常是:

 - Black            0x00
 - Blue             0x01
 - Green            0x02
 - Cyan             0x03
 - Red              0x04
 - Magenta          0x05
 - Brown            0x06
 - LightGray        0x07
 - DarkGray         0x08
 - LightBlue        0x09
 - LightGreen       0x0A
 - LightCyan        0x0B
 - LightRed         0x0C
 - LightMagenta     0x0D
 - LightBrown       0x0E
 - White            0x0F