INT 10h,  08h (8)        Read Character and Attribute At Cursor

    Reports the ASCII value and (in text mode) attribute of the character
    at the current cursor location of the specified display page.

       On entry:      AH         08h
                      BH         Display page number (text modes only)

       Returns:       AH         Attribute of character (text mode)
                      AL         ASCII value of character

       Registers destroyed:      AX, SP, BP, SI, DI

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       Notes:         In graphics mode, the display page need not be
                      specified.

                      The current character and attribute can be obtained
                      for any page, even if the page is not the current
                      active page.

                      In graphics mode, the service returns 00h in AL if
                      it does not recognize the character pattern.

                      Use Service 09h to write a character with a specific
                      attribute.