Compatibility: AT EGA VGA
DH,DL row,column to start writing
ES:BP address of start of text to write
Info: This displays a string of text, using a specified video attribute
and starting at a specified screen location.
It automatically updates the cursor location, leaving it one
column beyond the last character written.
This function treats these characters specially:
CR (0dH) cursor to start of same line
LF (0aH) cursor to current clm on next lower line
BEL (07H) beep the speaker
Notice that you must supply both CR+FL to perform a natural
"newline" (that is, to move the cursor to the start of the next
Note: This fn requires that you modify BP. When calling from high-
level languages such as C, be very careful to save and restore
BP, since it is used to keep track of the "stack frame".