100 POKE56,146:CLR:SC=1024:CM=54272:XT=0:YT=0:X=0:Y=0:R=24:C=39:DIMNA$(31)
110 SNAPSHOT=51000:POKE53280,11:POKE53281,12:GOSUB240
120 PRINT TAB(7)"SET UP AND COPY SCREENS":FORI=0TO1200:NEXT
130 GOSUB240:PRINTTAB(9)"SNAPSHOT DEMONSTRATION"
140 SYSSNAPSHOT,D,*:REM ERASE OLD SCREENS
150 FORI= 0 TO 31:X=I:Y=0:GOSUB250
160 X=X-1:Y=Y+1:IF X>=0 THEN GOSUB250:GOTO160
170 NA$(I)=STR$(I):NA$(I)=RIGHT$(NA$(I),LEN(NA$(I))-1):N$=NA$(I)
180 SYSSNAPSHOT,C,N$:NEXT:REM COPY SCREEN
190 GOSUB240:PRINT TAB(8)"SNAPSHOT PRINTS SCREENS"
200 PRINT:PRINT:PRINT TAB(10)"PRESS (STOP) TO END":FORI=0TO3000:NEXT
210 FORI=0TO31:N$=NA$(I):SYSSNAPSHOT,P,N$:NEXT
220 FORI=31TO0STEP-1:N$=NA$(I):SYSSNAPSHOT,P,N$:NEXT
230 GOTO210
240 PRINT"[147]":FORI=0TO9:PRINT:NEXT:RETURN
250 IF Y>24 THEN300
260 XT=X:YT=Y:CH=78:GOSUB310
270 XT=C-X:CH=77:GOSUB310
280 YT=R-Y:CH=78:GOSUB310
290 XT=X:CH=77:GOSUB310
300 RETURN
310 P=40*YT+XT+SC:IFPEEK(P)=77ORPEEK(P)=78THENCH=86
320 POKEP,CH:POKEP+CM,0
330 RETURN