LUNAR2.m

LUNAR2 ;PROGRAM MOON

100 ;MAIN DRIVER

 W *7 S %LN=1 X %TC

 W "ATTENTION APOLLO!",!

 W "FAILURE IN MAIN COMPUTER DESCENT MODULE...",!

 W "MODULE WILL HAVE TO BE LANDED UNDER MANUAL CONTROL",!

 W "YOU MAY ADJUST THE RATE OF BURN BETWEEN 0 AND 100 kg/s",!

 W *7

 D 300 R !,"DO YOU WANT TO TRY AGAIN?",A S PA=0 S:A="Y" PA=1

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300 ;DESCENT STAGE

 R !,"TYPE 'RETURN' WHEN YOU ARE READY",A,!,"OK" W *7 H 1 D 600

 S H=20000,X=68,V=1000,F=3500,T=0,G=1.62,M=3500

 S %LN=1,%CO=1 X %TP W "TIME(s) HEIGHT(m) VELOCITY(m/s)    FUEL(kg)    BURN(kg/s) "

315 S %LN=1,%CO=78 X %TP W !,?2,T,?8,H,?21,V,?36,F,?50 R "?",B,"   " D:(B>100)!(B<0) 500

 F K=1:1:5 S V=V-((P*B*100\1/100)/M*100\1/100)+G,M=M-B,F=F-B,H=H-V D 700 G:H'>0 321 G:F'>0 371

 S T=T+5 G 315

321 D:V>20 900 W *7,!!,"TOUCHDOWN AT ",T+K," seconds",!,"LANDING VELOCITY ",V,"m/s",!

 G:V>8 325 W *7,"CONGRATULATIONS ON A SAFE LANDING !",! Q

325 G:V>20 327 W *7,"WOULD YOU PLEASE CLEAN BUZZ ALDRIN OFF THE WALLS!",! Q

327 W *7,*7,"YOU HAVE ACHEIVED IMMORTALITY - THEY ARE GOING TO NAME THE CRATER AFTER YOU !",*7,!

 Q

371 ;OUT OF FUEL

 W *7,!,"OUT OF FUEL",*7 F K=1:1:1000 S V=V+G,H=H-V D 700 G:H'>0 321

 Q

500 ;ILLEGAL BURN

 G:B>100 513 W !,*7,"ZERO BURN ASSUMED" S B=0 Q

513 W !,*7,"JET TUBES OVERHEATING - REDUCE BURN",*7,! X $P($T(515)," ",2,99) X $P($T(517)," ",2,99) X $P($T(521)," ",2,99) Q

515 W "TUBE BURN OUT" S P=P-200 S:P'>0 F=0

517 W "TWO TUBES BURNT OUT" S P=P-400 S:P'>0 F=0

521 R !,"WHAT NEW BURN ?",B

 S %LN=1,%CO=1 X %TP W !

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600 ;DISPLAY BACKGROUND

 S %LN=1 X %TC

 S %LN=19,%CO=1 X %TP W !

 W ?22," ^",?53,"/\",!

 W ?22,"/ \/\",?52,"/  \",!

 W ?7,"/\",?21,"/     \",?51,"/    \",!

 W ?6,"/ \/\",?20,"/       \",?47,"/\ /      \",!

 W "_o___/     \___o_/\/         \________________/  \       \____________________"

 S Y=38,X=68 X $P($T(720)," ",2,99) S Z=38,W=68

 Q

700 ;DISPLAY LUNAR MODULE

 S Y=54-(H/1000\1) S:Y>55 Y=55 S:Y<38 Y=38 I Y=Z,X=W G 725

 S %LN=Z-33,%CO=W-30 X %TP W " " S %LN=Z-32,%CO=W-31 X %TP W "   " S %LN=Z-31,%CO=W-31 X %TP W "    "

720 S %LN=Y-33,%CO=X-30 X %TP W "_" S %LN=Y-32,%CO=X-31 X %TP W "(#)" S %LN=Y-31,%CO=X-31 X %TP W "/-\"

725 S Z=Y,W=X S %LN=1,%CO=1 X %TP W !

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900 ;ON THE ROCKS

 S %LN=Y-33,%CO=X-31 X %TP W "\M/"

 S %LN=Y-32 X %TP W "<@>"

 S %LN=Y-31 X %TP W "/W\"

 S %LN=1,%CO=1 X %TP F Z=1:1:80 W " "

 W ! F Z=1:1:80 W " "

 W !!,*7,"CRASH LANDING ON MOON...NO SURVIVORS",*7,!!

 S H=0,CR=1

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