dos33fsprogs/ksp/applesoft/ksp.bas

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' *********************************************
' *** KSP by Vince Weaver, vince@deater.net ***
' *** ***
' *** A VMW Software Production ***
' *********************************************
'
' http://www.deater.net/weave/vmwprod/ksp/
' https://github.com/deater/dos33fsprogs
'
' Note: you'll want to run this through my tokenize_asoft
' routine to remove these comments and create a proper
' Applesoft BASIC file
' Why not use REM statements? They take up valuable space
' in RAM (we optimistically only have around 12kB to play with)
' as well as slow down execution as BASIC is interpreted.
'
' Variable List: (Note, in Applesoft only first 2 chars matter)
' A$ = keypressed
' AN$ = astrounat name
' C$ = contract name
' D$ = ASCII(4) indicating we have a DOS command
' AD() = astronaut dead
' AN = rocket angle
' AX/AY= rocket x/y acceleration
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' BF = bingo fuel (out of fuel) in stage
' C = temp color
' CQ = current quadrant (i.e. background to display)
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' DT = delta time (for time acceleration)
' DV() = deltaV
' EM() = per-stage empty mass
' FM() = per-stage fuel mass
' EN() = engines per stage
' FF() = fuel flow
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' FL = fuel left (percent)
' FT() = fuel tanks per stack
' G = gravity
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' GA = gravity angle (radians)
' GX/GY= gravity X/Y vector
' H = horizon
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' HX/HY= orbital points in orbit mode
' I = loop iterator
' J = loop iterator
' KE = astronaut eyes
' KR = planet radius
' LN = launched
' MX = maximum altitude reached
' OM = orbit mode (view)
' P = number of parachutes
' PD = parachutes deployed
' RA = distance to center of planet
' RR = altitude
' RX/RY= rocket x,y position
' S = Current Stage Number
' SR = Number of struts
' SS = Number of stages
' TH() = stage thrust
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' TR = engines are thrusting
' T = time
' SM() = per-stage stage mass
' ST() = Stacks per stage
' TM() = per-stage total mass
' TV = terminal velocity
' TW() = thrust/weight ratio
' V = velocity magnitude
' VX/VY= velocity x/y vector
' W = Which astronaut
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' X/Y = temp X/Y
' ZX/ZY= Vx0 and Vy0
'
' Clear screen
10 HOME:HGR:D$=CHR$(4)
' *** REM *** SQUAD LOADING SCREEN ***
100 PRINT D$"BLOAD SQUAD.HGR,A$2000"
' *** REM *** Randmoize the start of the witty loading comments
580 S=0:I=INT(RND(1)*8)+1
' *** REM *** Prepare for the status bar
590 VTAB 21: PRINT " ";:FOR I=1 TO 32: PRINT ".";: NEXT I
' *** REM *** LOADING SCREEN ***
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700 FOR J=1 TO 32
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708 IF J=16 THEN PRINT: PRINT D$"BLOAD LOADING.HGR,A$2000"
710 HTAB J+4:VTAB 21
720 INVERSE: PRINT " ";: NORMAL
790 S=S+1: IF S=4 THEN S=0
795 IF S<>1 GOTO 840
800 I=I+1: IF I > 8 THEN I=1
802 VTAB 22: HTAB 1:PRINT " ";
805 ON I GOSUB 850,851,852,853,854,855,856,857
' *** REM *** Slow down so we don't load so fast
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840 FOR T=1 TO 250: NEXT T
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842 NEXT J
845 GOTO 900
850 HTAB 10:PRINT "Adding Extraneous Ks":RETURN
851 HTAB 14:PRINT "Locating Jeb":RETURN
852 HTAB 11:PRINT "Breaking Quicksaves":RETURN
853 HTAB 12:PRINT "Patching Conics":RETURN
854 HTAB 12:PRINT "Spinning up Duna":RETURN
855 HTAB 11:PRINT "Warming up the 6502":RETURN
856 HTAB 10:PRINT "Preparing Explosions":RETURN
857 HTAB 10:PRINT "Unleashing the Kraken":RETURN
' *** REM *** TITLE SCREEN ***
900 HOME: PRINT: PRINT D$"BLOAD TITLE.HGR,A$2000"
905 HTAB 25:VTAB 24: PRINT "VERSION 1.3.7.1";
' *** REM ****************
' *** REM KSP THEME MUSIC
' *** REM SEE http://eightbitsoundandfury.ld8.org/programming.html
' *** REM This loads an assembly language routine that generates
' *** REM Square waves on the speaker output
' *** REM ****************
910 FOR L = 770 TO 790: READ V: POKE L,V: NEXT L
920 DATA 173,48,192,136,208,5,206,1,3,240,9
930 DATA 202,208,245,174,0,3,76,2,3,96
' *** REM on qbasic this would be PLAY "L2ECGL4CEGL2B-AGL4CEGL2B-AGCD"
940 FOR I=1 TO 17: READ F: READ D: POKE 768,F: POKE 769,D: CALL 770: NEXT I
950 DATA 202,216,255,216,170,216
955 DATA 255,108,202,108,170,108
960 DATA 143,216,152,216,170,216
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965 DATA 255,108,202,108,170,108
970 DATA 143,216,152,216,170,216,255,216,227,255
' *** REM *** DONE LOADING ***
' *** REM *** Wait for keypress
990 VTAB 1: GET A$
' *******************
' *** VAB ***
' *******************
'**** REM *** Point to shape table location and load in VAB table
1000 POKE 232,0:POKE 233,16
1015 PRINT:PRINT D$"BLOAD VAB.SHAPE,A$1000"
1035 HGR : ROT= 0: SCALE= 2
1037 PRINT D$"BLOAD VAB.HGR,A$2000"
1150 X=132:Y=28
1155 XDRAW 1 AT X,Y+2
1200 HOME: INVERSE : VTAB 21: HTAB 7: PRINT " VEHICLE ASSEMBLY BUILDING "
1205 NORMAL:PRINT:PRINT "HOW MANY STAGES? (1-3)";:INPUT S
1230 FOR I = 1 TO S
1240 PRINT "HOW MANY STACKS, STAGE ";I;" (1-3)";:INPUT T:ST(I) = T
1260 PRINT "HOW MANY FUEL TANKS PER STACK, STAGE ";I;" (1-2)";
1265 INPUT F: FT(I) = F
1268 FOR J = 1 TO F
1270 XDRAW 2 AT X, Y+13*J
1272 IF T >1 THEN XDRAW 2 AT X-14, Y+13*J
1274 IF T >2 THEN XDRAW 2 AT X+14, Y+13*J
1278 NEXT J
1279 Y=Y+13*F
1280 PRINT "HOW MANY ENGINES, STAGE ";I;" (1-";T;")";:INPUT E
1285 EN(I) = E
1290 XDRAW 1 AT X, Y+8
1292 IF E >1 THEN XDRAW 1 AT X-14, Y+8
1294 IF E >2 THEN XDRAW 1 AT X+14, Y+8
1297 Y=Y+6
1300 NEXT I
1330 PRINT "HOW MANY PARACHUTES? (0-3)";:INPUT P
1350 PRINT "HOW MANY STRUTS? (0-20000)";:INPUT SR
1370 SS=S
' *********************************
' *** ASTRONAUT COMPLEX ***
' *********************************
1500 TEXT: HOME: HTAB 11
1515 INVERSE: PRINT "ASTRONAUT COMPLEX": NORMAL
1520 PRINT:PRINT "CHOOSE ONE KERBAL FOR THIS MISSION:":PRINT
1530 FOR I=1 TO 8
1540 IF AD(I) GOTO 1600
1550 ON I GOSUB 1641,1642,1643,1644,1645,1646,1647,1648
1560 PRINT " ";I;". ";AN$,AJ$;" S: ";AS$;" C: ";AC$
1600 NEXT I
1605 PRINT: INPUT W
1615 IF W<1 OR W>8 THEN PRINT "INVALID INPUT, PLEASE TRY AGAIN!": GOTO 1610
1630 ON W GOSUB 1641,1642,1643,1644,1645,1646,1647,1648
1630 GOTO 1776
1641 AN$="JEBEDIAH" :AJ$="PILOT":AS$="****":AC$="****":RETURN
1642 AN$="VALENTINA":AJ$="PILOT":AS$="****":AC$="****":RETURN
1643 AN$="KAI" :AJ$="SCI ":AS$="*** ":AC$="***":RETURN
1644 AN$="KUROSHIN" :AJ$="ENGR ":AS$="** ":AC$="*":RETURN
1645 AN$="DESKTOP" :AJ$="ENGR ":AS$="* ":AC$="***":RETURN
1646 AN$="SLASHDOT" :AJ$="SCI ":AS$="*** ":AC$="*":RETURN
1647 AN$="ZURGTROYD":AJ$="PILOT":AS$="** ":AC$="***":RETURN
1648 AN$="DAPHTY" :AJ$="ENGR ":AS$="*** ":AC$="***":RETURN
'*** REM DEBUG, Uncomment and Jump here to skip loading
'1700 REM TEXT:HOME
'1720 REM AN$="ZURGTROYD":SS=3
'1750 REM EN(1)=1:ST(1)=1:FT(1)=1
'1751 REM EN(2)=2:ST(2)=2:FT(2)=1
'1752 REM EN(3)=3:ST(3)=3:FT(3)=1
'************************
'* Rocket Summary ***
'************************
'*** REM Load Rocket Shape Table
1776 POKE 232,0:POKE 233,16
1783 PRINT D$"BLOAD ROCKET.SHAPE,A$1000"
1800 HOME:PRINT "ROCKET SUMMARY:":PRINT
1802 G=-9.8:S=SS:DT=1
1805 FOR I=1 TO S
'*** REM EmptyMass=Engines*1.5T+(Stacks*FuelTanks)*0.5T
1810 EM(I)=EN(I)*1.5+ST(I)*FT(I)*0.5
'*** REM First stage also has a 1T capsule
1812 IF I=1 THEN EM(I)=EM(I)+1.0
'*** REM FuelMass=(Stacks*FuelTanks)*4T
1814 FM(I)=ST(I)*FT(I)*4.0
'*** REM StageFuel=FuelMass (one gets decremented as we use it up)
1815 SF(I)=FM(I)
'*** REM StageMass=EmptyMass+FuelMass
1816 SM(I)=EM(I)+FM(I)
'*** REM Total mass of stage includes all higher stages
1820 TM(I)=0
1822 FOR J=1 TO I
1825 TM(I)=TM(I)+SM(J)
1830 NEXT J
'*** Thrust=NumberOfEngines*168kN
1835 TH(I)=EN(I)*168
'*** DeltaV=ISP*gravity*ln(total_mass/empty_mass)
1840 DV(I)=270*-G*LOG(TM(I)/(TM(I)-FM(I)))
'*** Thrust/Weight Ratio
1850 TW(I)=TH(I)/(TM(I)*-G)
'*** Fuel Flow
1855 FF(I)=TH(I)/(270*-G)
1990 PRINT "STAGE: ";4-I
1991 PRINT " TANKS=";ST(I)*FT(I);" ENGINES=";EN(I)
1992 PRINT " STAGE MASS=";SM(I);" TOTAL MASS=";TM(I)
1993 PRINT " DELTAV=";DV(I)
1995 PRINT " TWR=";TW(I)
2000 NEXT I
2998 GET A$
2999 HOME
'******************************
'*** Main Loop ****
'******************************
'
'******************************
'*** Initialize Variables ***
'******************************
3000 AN=0:GX=0:GY=-9.8:GA=0:V=0:VX=0:VY=0:AX=0:AY=0:KR=600000
3016 RX=0:RY=KR+10:RA=KR+10:TR=0:T=0:BF=0:MX=0:PD=0:LN=0:CQ=0:OM=0
3020 HGR:ROT=0:SCALE=2:H=0
'**** REM ** LAUNCHPAD **
3035 PRINT:PRINT D$"BLOAD LAUNCHPAD.HGR,A$2000"
'**** REM DRAW HORIZON (GREEN)
3038 HCOLOR=1:HPLOT 1,80 TO 132,80: HPLOT 148,80 TO 247,80
'**** REM DRAW GANTRY (WHITE)
3039 HCOLOR=3:HPLOT 110,110 TO 110,60:HPLOT TO 130,60: HPLOT 110,70 TO 130,70
'**** DRAW SHIP
3040 XDRAW 1+((S-1)*2)+TR AT 140,80
4000 REM ** MAIN LOOP **
'**** REM ** if not launched yet then skip physics
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4002 IF LN=0 GOTO 5032
'**** Calculate altitude and set maximum if we are at new record
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4003 RR=RA-KR:IF RR>MX THEN MX=RR
'**** If orbit mode then skip drawing horizon, etc
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4004 IF OM=1 GOTO 4018
'**** If above 1.8km don't draw horizon
'**** FIXME: do we need to check OM again?
'**** FIXME: we draw the horizon one pixel too far to right
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4005 IF RR>1800 OR OM=1 THEN GOTO 4012
'**** Erase old horizon
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4007 HCOLOR=0:HPLOT 1,80+H TO 132,80+H:HPLOT 148,80+H TO 247,80+H
'**** Calculate and draw new horizon
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4010 H=RR/20:HCOLOR=1:HPLOT 1,80+H TO 132,80+H:HPLOT 148,80+H TO 247,80+H
'**** REM *** Check if need to change to surface mode
4012 IF RR<40000 AND CQ<>0 THEN GOSUB 7600
'**** REM *** If in surface mode, skip ahead
4014 IF RR<40000 GOTO 4018
'**** REM *** See if need to change to high-altitude mode
4016 IF RR>40000 AND CQ<>1 THEN GOSUB 7700
'**** REM *** Calculate Fuel Left
4018 FL=FM(S)*100/SF(S)
'**** REM *** If not thrusting then skip ahead
4020 IF TR<>1 THEN GOTO 4050
'**** REM *** If out of fuel then shut down engines
4025 IF FM(S)<0.1 THEN FM(S)=0:BF=1:AX=0:AY=0:GOTO 4050
'**** REM *** Calculate acceleration vectors based on thrust and mass
4030 AX=(TH(S)/TM(S))*SIN(AN):AY=(TH(S)/TM(S))*COS(AN)
'**** REM *** Update masses now that fuel was used
4040 FM(S)=FM(S)-FF(S):TM(S)=TM(S)-FF(S)
4047 GOTO 4060
'**** REM ELSE NOT THRUSTING
4050 AX=0:AY=0
'**** REM ENDIF
'**** REM *** Calculate angle to center of planet
4060 GA=ATN(RX/RY)
'**** REM *** Wrap since ATN can only return -PI/2 to PI/2
4065 IF RY<0 THEN GA=GA+3.14
'**** REM *** Calculate gravity vectors
4070 GY=COS(GA)*G:GX=SIN(GA)*G:AY=AY+GY:AX=AX+GX
'**** REM *** v=v0+at
4090 ZX=VX:ZY=VY:VY=ZY+AY*DT:VX=ZX+AX*DT:V=SQR(VX*VX+VY*VY)
'**** REM *** deltaX=0.5(V0+V)t
5012 RY=RY+0.5*(ZY+VY)*DT:RX=RX+0.5*(ZX+VX)*DT:RA=SQR(RX*RX+RY*RY)
'**** REM *** If new position below surface then crash
5020 IF RA<KR THEN GOTO 8000
'**** REM *** Calculate new gravity value based on altitude
5030 G=-9.8/((RA/KR)*(RA/KR))
'*****************************************
'*** Print status on bottom of screen ***
'*****************************************
5032 VTAB 21:PRINT "TIME: ";T,"STAGE: ";4-S;" ";AN$
5045 PRINT "ALT: ";INT((RA-KR)/1000);"KM","ANGLE=";R*5.625;" "
5060 PRINT "VEL: ";INT(V);"M/S","FUEL: ";INT(FL);"% "
'**** REM *** If out of fuel then cut off thrusting
5100 IF BF=1 THEN BF=0:A$="X":GOTO 5555
'********************************
'*** Check for keyboard input ***
'********************************
'*** No non-blocking input in Applesoft
'*** so need to check keyboard buffer directly
5115 Q=PEEK(-16384):IF Q<128 THEN GOTO 6095
5222 A$=CHR$(Q-128):POKE 49168,0
'********************************
'*** Erase the old ship
'********************************
5555 IF OM<>1 THEN XDRAW 1+((S-1)*2)+TR AT 140,80
'********************************
'*** Handle keypresses
'********************************
6060 IF A$="Q" THEN GOTO 9000
'**** A/D rotate ship
6061 IF A$="A" THEN R=R-8:AN=AN-0.7853
6062 IF A$="D" THEN R=R+8:AN=AN+0.7853
'**** C (undocumented) forces crash
6063 IF A$="C" THEN GOTO 8000
'**** Z/X enable/disable engines
6064 IF A$="Z" THEN TR=1
6065 IF A$="X" THEN TR=0
'**** >/< speed/slow time
6066 IF A$=">" THEN DT=DT+1
6067 IF A$="<" THEN DT=DT-1:IF DT<1 THEN DT=1
'**** M switched to/from orbit mode
6068 IF A$="M" AND OM=1 THEN OM=0:CQ=-1:GOTO 4000
6069 IF A$="M" AND OM=0 THEN OM=1:HOME:PRINT:PRINT D$"BLOAD GLOBE.HGR,A$2000":GOTO 6095
'**** space launches ship or stages/parachutes
'**** we make a click noise on the speaker if we stage
6070 IF A$=" " AND LN=1 THEN S=S-1:XX=PEEK(-16336):IF S<1 AND P>0 AND PD=0 THEN PD=1:GOSUB 7800
6072 IF S<1 THEN S=1
6074 IF A$=" " AND LN=0 THEN GOSUB 7500
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'**************************************
'*** Adjust values after keypresses ***
'**************************************
'**** Adjust rotation
6075 IF R=64 THEN R=0:AN=0
6076 IF R=-8 THEN R=56
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'**** REM Adjust astronaut face: FIXME better cues
'**** REM always start neutral
6077 IF OM<>1 THEN GOSUB 8200
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'**** REM If flying upside down then frown
6078 IF OM<>1 AND R>20 AND R<48 THEN GOSUB 8210:GOTO 6080
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'**** REM If going up then smile
6079 IF OM<>1 AND VY>100 THEN GOSUB 8220
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'**** Adjust rotation
6080 ROT=R
'**** Re-draw ship
6090 IF OM<>1 THEN XDRAW 1+((S-1)*2)+TR AT 140,80
'**** In orbit mode, plot orbit
6095 IF OM=1 THEN HX=INT(RX/25000)+140:HY=INT(-RY/25000)+85:HCOLOR=3:HPLOT HX,HY
'**** Adjust Time plus astronaut eye count
6118 T=T+DT:EC=EC+DT
'**** If enough time has passed update eyes
6150 IF OM<>1 AND EC>30 THEN EC=0:GOSUB 8100
'**** REM Loop forever
6200 GOTO 4000
'***************
'*** LAUNCH ****
'***************
'**** REM Erase gantry
7500 HCOLOR=0:HPLOT 110,110 TO 110,60:HPLOT TO 130,60: HPLOT 110,70 TO 130,70
'**** REM click the speaker
7520 XX=PEEK(-16336)
7530 TR=1:LN=1
'**** Make astronaut smile
7535 GOSUB 8220
7540 RETURN
'********************
'**** Ground Mode ***
'********************
7600 HOME:PRINT:PRINT D$"BLOAD LAUNCHPAD.HGR,A$2000"
7615 XDRAW 1+((S-1)*2)+TR AT 140,80
7620 CQ=0
7650 RETURN
'********************
'*** Space Mode *****
'********************
'*** Up mode, sort of intend to have up/down/left/right images
'*** but only up implemented right now
7700 HOME:PRINT:PRINT D$"BLOAD ORBIT_TOP.HGR,A$2000"
7710 XDRAW 1+((S-1)*2)+TR AT 140,80
7720 CQ=1
7750 RETURN
'*************************
'*** Deploy Parachutes ***
'*************************
7800 HX=0:HY=0
7805 IF PD=1 THEN HX=5:HY=3
7810 HCOLOR=HX:HPLOT 120,20 TO 160,20 TO 180,40 TO 100,40 TO 120,20
7820 HCOLOR=HY:HPLOT 100,40 TO 140,80 TO 180,40
7830 RETURN
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'***************
'**** CRASH ****
'***************
'**** Make ship bigger
8000 SCALE=3
'**** Make astronaut frown
8015 GOSUB 8200
'**** Spin ship around while clicking
8020 FOR I=0 TO 64 STEP 8: ROT=I:XDRAW 1+((S-1)*2)+TR AT 140,80: XX=PEEK(-16336):NEXT I
'**** Draw explosion
8030 FOR I=1 TO 50
8040 X=INT(RND(1)*80)+1:Y=INT(RND(1)*80)+1
8050 C=INT(RND(1)*7)+1:HCOLOR=C
8060 HPLOT 140,80 TO 100+X,40+Y
8070 XX=PEEK(-16336)
8080 NEXT I
'**** Kill off the astronaut
8085 AD(W)=1
8090 GOTO 9000
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'**************************
'*** Astronaut Eyes ***
'**************************
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'**** Erase old ones
8100 HCOLOR=3:HPLOT 258,150 TO 263,150:HPLOT 265,150 TO 270,150
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'*** Randomly pick new ones
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8110 KE=INT(RND(1)*3)
'**** Draw new ones
8120 HCOLOR=0:HPLOT 258+(2*KE),150 TO 259+(2*KE),150
8125 HPLOT 265+(2*KE),150 TO 266+(2*KE),150
8130 RETURN
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'**************************
'*** Astronaut Frown ***
'**************************
'**** Erase old mouth
8200 HCOLOR=1:HPLOT 259,155 TO 271,155:HPLOT 259,156 TO 271,156
'**** Draw frown
8205 HCOLOR=0:HPLOT 261,155 TO 269,155:HPLOT 259,156 TO 271,156
8207 RETURN
'**************************
'*** Astronaut Neutral ***
'**************************
'**** Erase old mouth
8210 HCOLOR=1:HPLOT 259,155 TO 271,155:HPLOT 259,156 TO 271,156
'**** Draw new mouth
8215 HCOLOR=0:HPLOT 259,155 TO 271,155
8217 RETURN
'**************************
'*** Astronaut Smile ***
'**************************
'**** Erase old mouth
8220 HCOLOR=1:HPLOT 259,155 TO 271,155:HPLOT 259,156 TO 271,156
'**** Draw new mouth
8225 HCOLOR=0:HPLOT 259,155 TO 271,155:HPLOT 261,156 TO 269,156
8227 RETURN
'*****************************
'*** CONTRACT COMPLETE ***
'*****************************
9000 IF MX<40000 THEN C$="CRASH SHIP":F$="0.30":E$="-1":GOTO 9010
9007 C$="REACH SPACE":F$="200":E$="20"
9010 TEXT:HOME
9020 HTAB 10:VTAB 9
9021 FOR I=1 TO 20: PRINT "*";: NEXT I: PRINT "*"
9023 HTAB 10: PRINT "* ";:INVERSE: PRINT "CONTRACT COMPLETE";:NORMAL: PRINT " *"
9024 HTAB 10: PRINT "* ";
9026 L=10-(LEN(C$))/2
9027 HTAB 10+L:PRINT C$;:HTAB 30: PRINT "*"
9030 HTAB 10:PRINT "* FUNDS ";F$;:HTAB 30: PRINT "*"
9030 HTAB 10:PRINT "* EXPERIENCE ";E$;:HTAB 30: PRINT "*"
9040 HTAB 10
9042 FOR I=1 TO 20: PRINT "*";: NEXT I:PRINT "*"
9100 VTAB 16
9110 PRINT "NOW WHAT?"
9120 PRINT " 1. RETURN TO THE VAB"
9130 PRINT " 2. RETURN TO ASTRO COMPLEX"
9140 PRINT " 3. RETURN TO LAUNCH"
9145 PRINT " 4. HELP"
9150 PRINT " 5. QUIT GAME"
9160 PRINT "---> ";
9170 GET A$
9171 IF A$="1" GOTO 1000
9172 IF A$="2" GOTO 1500
9173 IF A$="3" GOTO 1776
9174 IF A$="4" OR A$="H" GOTO 9200
9175 IF A$="5" OR A$="Q" THEN TEXT:HOME:END
9176 GOTO 9160
'*******************
'*** HELP SCREEN ***
'*******************
9200 HOME:PRINT "KSP-APPLE-II BY VINCE WEAVER"
9230 PRINT " APPLE II FOREVER"
9240 PRINT " A,D - STEER SHIP LEFT/RIGHT"
9250 PRINT " Z - START ENGINES"
9260 PRINT " X - CUT ENGINES"
9270 PRINT " SPACE - LAUNCH,STAGE"
9275 PRINT " M - SWITCH TO ORBITAL VIEW"
9277 PRINT " <,> - FAST FORWARD"
9280 PRINT " ESC - QUIT"
9300 GET A$
9320 GOTO 9010