INT 62 u - FGDRIVER v4.02 - "FG_SETLINES" - SET TEXT ROWS ON SCREEN
AX = 00AFh
BX = new screen size (25, 43, 50)
Note: the FGDRIVER functions are rearranged with each major release, but
their parameters do not change (see #03474 at AX=0000h)
SeeAlso: AX=0047h