INT 21 - DOS 1+ - WRITE CHARACTER TO STANDARD OUTPUT
AH = 02h
DL = character to write
Return: AL = last character output (despite the official docs which state
nothing is returned) (at least DOS 3.3-5.0)
Notes:  ^C/^Break are checked, and INT 23 executed if pressed
standard output is always the screen under DOS 1.x, but may be
redirected under DOS 2+
the last character output will be the character in DL unless DL=09h
on entry, in which case AL=20h as tabs are expanded to blanks
SeeAlso: AH=09h

See also: 2106

2102 - DOS 1+ - WRITE CHARACTER TO STANDARD OUTPUT