100 DEFine PROCedure SMODE$
110  LOCal ch,scr,loop
120  LOCal mode$,scr$
130  RESTORE 220
140  FOR scr=1 TO 4
150   READ mode$,scr$
160   ch=FOPEN('con_'&mode$)
170   IF scr=4 OR ch>0 : EXIT scr
180  END FOR scr
190  CLOSE#ch
200  RETurn scr$
210 :
220  DATA '800x600a0x0','SVGA'
230  DATA '640x480a0x0','VGA'
240  DATA '640x350a0x0','EGA'
250  DATA '512x256a0x0','QL'
260 :
270 END DEFine SMODE$