10 GOSUB 50000: x0=360:y0=12: f%=1
20 PRINT CHR$(27)+"0";CHRS(27)+"E";CHR$(27)+"f";
30 FOR a=0 TO 6.2832 STEP 0.005
40 x%=CINT(x0+350*COS(a)):y%=CINT(y0+120*SIN(a))
50 CALL PLOT(x%,y%,f%):NEXT
60 y%=y0:FOR x%=x0-350 TO x0+350:CALL plot(x%,y%,f%):NEXT
70 x%=x0:FOR y%=y0-120 TO y0+120:CALL plot(x%,y%,f%):NEXT
80 PRINT CHR$(27)+"e";CHR$(27)+"1";CHR$(27)+"Y"+CHR$(59)+CHR$(32):END
50000 MEMORY &HBFFF:plot=&HC000:A=PLOT:E=0
50010 RESTORE 50120
50020 FOR f=0 TO 14
50030 s=0
50040 FOR G=0 TO 7
50050 READ X$:X=VAL("&H"+X$)
50060 S=S+X:POKE A,X:A=A+1:NEXT
50070 READ X$:IF S<>VAL("&H"+X$) THEN E=E+1:PRINT "ERROR IN LINE ";10*(F+5012)
50080 NEXT
50090 IF E=0 THEN RETURN
50100 PRINT E; "ERROR";:IF E=1 THEN PRINT ELSE PRINT "S"
50110 STOP
50120 DATA 0A,32,7C,C0,4E,23,46,21,250
50130 DATA CF,02,A7,ED,42,D8,ED,43,4AF
50140 DATA 78,C0,EB,5E,23,56,7A,A7,41B
50150 DATA C0,93,3D,5F,ED,53,7A,C0,469
50160 DATA F3,ED,73,7D,C0,31,9D,C0,51E
50170 DATA 01,36,C0,CD,5A,FC,E9,00,403
50180 DATA ED,7B,7D,C0,FB,C9,2A,7A,50D
50190 DATA C0,29,11,00,B6,19,5E,23,24A
50200 DATA 56,7B,E6,F8,CB,27,CB,12,47E
50210 DATA 47,7B,E6,07,B0,5F,2A,78,360
50220 DATA C0,45,7D,E6,F8,6F,EB,19,4D3
50230 DATA 78,E6,07,3C,47,AF,37,1F,2ED
50240 DATA 10,FD,47,3A,7C,C0,A7,20,391
50250 DATA 05,78,2F,A6,77,C9,3D,78,347
50260 DATA 20,03,B6,77,C9,AE,77,C9,407