INT 62 - FGDRIVER v4.02 - "FG_WAITVR" - ENABLE/DISABLE VERTICAL RETRACE WAIT AX = 00DFh BX = new state (0000h disabled, 0001h enabled) Note: the FGDRIVER functions are rearranged with each major release, but their parameters do not change (see #03474 at AX=0000h)