Source Code
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These source-code files were obtained by digitally photographing the
Colossus 237 program listing from the private collection of original
AGC developer Fred Martin, and then modifying pre-existing Colossus 249
(Apollo 9) source files to incorporate changes. Note that the page images
presented online are of reduced quality, and that additional images
are available. Report any conversion errors or legibility
problems in page images to info@sandroid.org.
Notations on the program listing read, in part:GAP: ASSEMBLE REVISION 237 OF AGC PROGRAM COLOSSUS BY NASA 2021111-031 1:17 AUG. 24, 1968 |
034348,000002: # Copyright: Public domain.
034349,000003: # Filename: ENTRY_LEXICON.agc
034350,000004: # Purpose: Part of the source code for Colossus build 237.
034351,000005: # This is for the Command Module's (CM) Apollo Guidance
034352,000006: # Computer (AGC), we believe for Apollo 8.
034353,000007: # Assembler: yaYUL
034354,000008: # Contact: Jim Lawton <jim DOT lawton AT gmail DOT com>
034355,000009: # Website: www.ibiblio.org/apollo/index.html
034356,000010: # Page scans: www.ibiblio.org/apollo/ScansForConversion/Colossus237/
034357,000011: # Mod history: 2011-03-02 JL Adapted from corresponding Colossus 249 file.
034358,000012:
034359,000013: # # Page 788
034360,000014: # VARIABLE DESCRIPTION MAXIMUM VALUE * COMPUTER NAME
034361,000015: # -------- ----------- ------- ----- -------- ----
034362,000016:
034363,000017: # -
034364,000018: # URT0 INITIAL TARGET VECTOR 2 (UNIT VECTOR) = RTINIT
034365,000019: # -
034366,000020: # UZ UNIT VECTOR NORTH 1 = UNITW
034367,000021: # -
034368,000022: # V VELOCITY VECTOR 2 VSAT = VEL
034369,000023: # -
034370,000024: # R POSITION VECTOR 2 EXP 29 METERS = RN
034371,000025: # -
034372,000026: # VI INERTIAL VELOCITY 128 M/CENTISEC = VN
034373,000027: # -
034374,000028: # RTE VECTOR EAST AT INITIAL TARGET 2 = RTEAST
034375,000029: # -
034376,000030: # UTR NORMAL TO RTE AND UZ 2 = RTNORM
034377,000031: # -
034378,000032: # URT TARGET VECTOR 2 = RT
034379,000033: # -
034380,000034: # UNI UNIT NORMAL TO TRAJECTORY PLANE 2
034381,000035: # -
034382,000036: # DELV INTEGRATED ACCEL. FROM PIPAS 5.85 16384 CM/S
034383,000037: # -
034384,000038: # G GRAVITY VECTOR 128 M/CENTISEC = GDT/2
034385,000039:
034386,000040: # A0 INITIAL DRAG FOR UPCONTRL 805 FPSS FPSS=FT/SEC/SEC
034387,000041: # AHOOKDV TERM IN GAMMAL CALC. = AHOOK DVL 8
034388,000042: # A1 DRAG VALUE IN FACTOR CALCULATION 805 FPSS
034389,000043: # ALP CONST FOR UPCONTRL 1
034390,000044: # ASKEP KEPLER RANGE 21600 NM NM = NAUTICAL MILE
034391,000045: # ASP1 FINAL PHASE RANGE 21600 NM
034392,000046: # ASPUP UP-RANGE 21600 NM
034393,000047: # ASP3 GAMMA CORRECTION 21600 NM
034394,000048: # ASPDWN RANGE DOWN TO PULL-UP 21600 NM
034395,000049: # ASP PREDICTED RANGE 21600 NM NOT STORED
034396,000050: # COSG COSINE(GAMMAL) 2 = COSG/2
034397,000051: # C/D0 RECIPROCAL DRAG, -4/D0 B-8 64/FPSS
034398,000052: # D TOTAL ACCELERATION 805 FPSS
034399,000053: # D0 CONTROLLED CONSTANT D 805 FPSS
034400,000054: # DHOOK TERM IN GAMMAL COMPUTATION 805 FPSS
034401,000055: # DIFF THETNM-ASP (RANGE DIFFERENCE) 21600 NM
034402,000056: # DIFFOLD PREVIOUS VALUE OF DIFF 21600 NM
034403,000057: # DLEWD CHANGE IN LEWD 1
034404,000058: # DR REFERENCE DRAG FOR DOWNCONTROL 805 FPSS NOT STORED
034405,000059: # DREFR REFERENCE DRAG 805 FPSS NOT STORED
034406,000060: # DVL VS1-VL 2 VSAT
034407,000061: # E ECCENTRICITY 4 NOT STORED
034408,000062: # F1 DRANGE/D DRAG (FINAL PHASE) 2700/805 = FX +5
034409,000063: # F2 DRANGE/D RDOT (FINAL PHASE) 2700/2VS NM/FPS = FX +4
034410,000064: # # Page 789
034411,000065: # F3 DRANGE/D (L/D) 2700 NM = FX
034412,000066: # FACT1 CONST FOR UPCONTRL 805 FPSS
034413,000067: # FACT2 CONST FOR UPCONTRL 1/805 FPSS
034414,000068: # FACTOR USED IN UPCONTRL 1 * MAXIMUM VALUE DENOTES UNSCALED
034415,000069: # GAMMAL FLIGHT PATH ANGLE AT VL 1 RADIAN VARIABLE VALUE WHEN SCALED
034416,000070: # GAMMAL1 SIMPLE FORM OF GAMMAL 1 RADIAN VARIABLE HAS MAXIMUM VALUE OF ONE.
034417,000071:
034418,000072: # # Page 790
034419,000073: # VARIABLE DESCRIPTION MAXIMUM VALUE * COMPUTER NAME
034420,000074: # -------- ----------- ------- ----- -------- ----
034421,000075:
034422,000076: # HEADSUP INDICATOR FOR INITIAL ROLL 1
034423,000077: # KA DRAG TO LIFT UP IF DOWN 805 FPSS = KAT
034424,000078: # KLAT LATERAL SWITCH GAIN 1 (NOM = .0125)
034425,000079: # K2ROLL INDICATOR FOR ROLL SWITCH
034426,000080: # LAD MAX L/D (MIN ACTUAL VEHICLE L/D) 1
034427,000081: # LADPAD NOMINAL VEHICLE L/D, SP PAD LOAD 1 (NOM = 0.3)
034428,000082: # LATANG LATERAL RANGE 4 RADIANS
034429,000083: # LEQ EXCESS C.F. OVER GRAV=(VSQ-1)GS 128.8 FPSS
034430,000084: # LEWD UPCONTROL REFERENCE L/D 1
034431,000085: # LOD FINAL PHASE L/D 1 (NOM = 0.18)
034432,000086: # LODPAD FINAL PHASE L/D, SP PAD LOAD 1
034433,000087: # L/D DESIRED LIFT TO DRAG RATIO 1
034434,000088: # (VERTICAL PLANE)
034435,000089: # L/D1 TEMP STORAGE FOR L/D IN LATERAL 1
034436,000090: # L/DCMINR LAD COS(15DEG) 1 (NOM = 0.2895)
034437,000091: # PREDANGL PREDICTED RANGE (FINAL PHASE) 2700 NM = PREDANG
034438,000092: # Q2 FINAL PHASE RANGE -23500 Q3 21600 NM
034439,000093: # Q2 = FCN(LAD)
034440,000094: # Q7 MINIMUM DRAG FOR UPCONTROL 805 FPSS
034441,000095: # RDOT ALTITUDE RATE 2 VSAT
034442,000096: # RDOTREF REFERENCE RDOT FOR UPCONTROL 2 VSAT
034443,000097: # RDTR REFERENCE RDOT FOR DOWNCONT 2 VSAT NOT SAVED
034444,000098: # ROLLC ROLL COMMAND 1 REVOLUTION
034445,000099: # RTOGO RANGE TO GO (FINAL PHASE) 2700 NM = FX +2
034446,000100: # SL SINE OF LATITUDE 1 NOT SAVED
034447,000101: # T TIME B 28 CENTISEC = TIME2,TIME1
034448,000102: # THETA DESIRED RANGE (RADIANS) 2 PI RADIANS = THETAH
034449,000103: # THETNM DESIRED RANGE (NM) 21600 NM NON EXISTENT
034450,000104: # V VELOCITY MAGNITUDE 2 VSAT
034451,000105: # V1 INITIAL VELOCITY FOR UPCONTROL 2 VSAT
034452,000106: # VL EXIT VELOCITY FOR UPCONTROL 2 VSAT
034453,000107: # VREF REFERENCE VELOCITY FOR UPCONTROL 2 VSAT
034454,000108: # VS1 VSAT OR V1, WHICHEVER IS SMALLER 2 VSAT
034455,000109: # 2 2
034456,000110: # VBARS VL /VSAT 4
034457,000111: # 2 2
034458,000112: # VSQ NORMALIZED VEL. SQUARED = V /VSAT 4 = VSQUARE
034459,000113: # WT EARTH RATE TIMES TIME 1 REVOLUTION NOT SAVED
034460,000114: # = WIE (DTEAROT)
034461,000115: # X INTERMEDIATE VARIABLE IN G-LIMITER 2 VSAT NOT SAVED
034462,000116: # Y LATERAL MISS LIMIT 4 RADIANS NOT SAVED
034463,000117:
034464,000118: # # Page 791
034465,000119: # EXTRA COMPUTER ERASABLE LOCATIONS NOT SHOWN ON FLOW CHARTS
034466,000120: # ----------------------------------------------------------
034467,000121:
034468,000122: # VARIABLE DESCRIPTION MAXIMUM VALUE
034469,000123: # -------- ----------- ------- -----
034470,000124:
034471,000125: # GOTOADDR ADDRESS SELECTED BY SEQUENCER
034472,000126: # XPIPBUF BUFFER TO STORE X PIPA COUNTS
034473,000127: # YPIPBUF BUFFER TO STORE Y PIPA COUNTS
034474,000128: # ZPIPBUF BUFFER TO STORE Z PIPA COUNTS
034475,000129: # PIPCTR COUNTS PASSES THRU PIPA READ ROUTINE
034476,000130: # JJ INDEX IN FINAL PHASE TABLE LOOK-UP
034477,000131: # MM INDEX IN FINAL PHASE TABLE LOOK-UP
034478,000132: # GRAD INTERPOLATION FACTOR IN FINAL PHASE
034479,000133: # FX DRANGE/D L/D = F3 2700 NM
034480,000134: # FX + 1 AREF 805 FPSS
034481,000135: # FX + 2 RTOGO 2700 NM
034482,000136: # FX + 3 RDOTREF VSAT/4
034483,000137: # FX + 4 DRANGE/D RDOT = F2 21600/2VS NM/FPS
034484,000138: # FX + 5 DRANGE/D DRAG = F1 2700/805 NM/FPSS
034485,000139: # TEM1B TEMPORARY LOCATION
034486,000140: # TIME/RTO TIME OF INITIAL TARGET RTINIT B 28 CENTISEC
034487,000141: # DTEAROT EST TIME BETWEEN RTINIT AND RT B 28 CENTISEC
034488,000142:
034489,000143: # -
034490,000144: # UNITV UNIT V VECTOR 2
034491,000145: # -
034492,000146: # UNITR UNIT R VECTOR 2
034493,000147: # -
034494,000148: # -VREL NEGATIVE VELOCITY REL TO ATMOSP 2 VSAT
034495,000149:
034496,000150: # COMPUTER SWITCHES INITIAL STATE CM/FLAGS = STATE +6
034497,000151: # -------- -------- ------------- -------------------
034498,000152:
034499,000153: # ENTRYDSP DO ENTRY DISPLAY, IF SET NON-BRANCH (1) 92D, BIT13
034500,000154: # GONEPAST INDICATES OVERSHOOT OF TARGET NON-BRANCH (0) 95D, BIT10
034501,000155: # RELVELSW RELATIVE VELOCITY SWITCH NON-BRANCH (0) 96D, BIT 9
034502,000156: # EGSW FINAL PHASE SWITCH NON-BRANCH (0) 97D, BIT 8
034503,000157: # FIRSTPAS INITIAL PASS THRU HUNTEST NON-BRANCH (0) 98D, BIT 7
034504,000158: # HIND INDICATES ITERATION IN HUNTEST NON-BRANCH (0) 99D, BIT 6
034505,000159: # INRLSW INDICATES INIT ROLL ATTITUDE SET NON-BRANCH (0) 100D, BIT 5
034506,000160: # LATSW INHIBIT DOWNLIFT SWITCH IF NOT SET BRANCH (1) 101D, BIT 4
034507,000161: # .05GSW INDICATES DRAG EXCEEDS .05 GS BRANCH (0) 102D, BIT 3
034508,000162:
034509,000163: # GONEBY INDICATES GONE PAST TARGET (SET) SELF-INITIALZNG 112D, BIT 8
034510,000164:
034511,000165: # # Page 792
034512,000166: # CONSTANTS AND GAINS VALUE
034513,000167: # ------------------- -----
034514,000168:
034515,000169: # C1 FACTOR IN ALP COMPUTATION 1.25
034516,000170: # C16 CONSTD GAIN ON DRAG .01
034517,000171: # C17 CONSTD GAIN ON RDOT .001
034518,000172: # C18 BIAS VEL. FOR FINAL PHASE START 500 FPS
034519,000173: # C20 MAX DRAG FOR DOWN-LIFT 175 FPSS
034520,000174: # CHOOK FACTOR IN AHOOK COMPUTATION .25
034521,000175: # CH1 FACTOR IN GAMMAL COMPUTATION 1.0
034522,000176: # COS15 COS( 15 DEG) .965
034523,000177: # DLEWD0 INITIAL VARIATION IN LEWD -.05
034524,000178: # D2 DRAG TO CHANGE LEWD 175 FPSS
034525,000179: # DT COMPUTATION CYCLE TIME INTERVAL 2 SEC.
034526,000180: # GMAX MAXIMUM ACCELERATION 257.6 FPSS (8 G-S)
034527,000181: # KA1 FACTOR IN KA CALC 1.3 GS
034528,000182: # KA2 FACTOR IN KA CALC .2 GS
034529,000183: # KA3 FACTOR IN D0 CALC 90 FPSS
034530,000184: # KA4 FACTOR IN D0 CALC 40 FPSS
034531,000185: # KB1 OPTIMIZED UPCONTROL GAIN 3.4
034532,000186: # KB2 OPTIMIZED UPCONTROL GAIN .0034
034533,000187: # KDMIN INCREMENT ON Q7 TO DETECT END OF KEPLER PHASE .5 FPSS
034534,000188: # KTETA TIME OF FLIGHT CONSTANT 1000
034535,000189: # KLAT1 FACTOR IN KLAT CALC 1/24
034536,000190: # K44 GAIN USED IN INITIAL ROLL SECTION 19749550 FPS
034537,000191: # LATBIAS LATERAL SWITCH BIAS TERM .41252961 NM
034538,000192: # LEWD1 NOMINAL UPCONTROL L/D .15
034539,000193: # POINT1 FACTOR TO REDUCE UPCONTROL GAIN .1
034540,000194: # Q2 FINAL PHASE RANGE - 23500 Q3 -1002 NM
034541,000195: # Q3 FINAL PHASE DRANGE/D V .07 NM/FPS
034542,000196: # Q5 FINAL PHASE DRANGE/ D GAMMA 7050 NM/RAD
034543,000197: # Q6 FINAL PHASE INITIAL FLIGHT PATH ANGLE .0349 RAD
034544,000198: # Q7F MIN DRAG FOR UPCONTROL 6 FPSS
034545,000199: # Q7MIN IN VALUE FOR Q7 IN FACTOR CALCULATION 40 FPSS
034546,000200: # Q19 FACTOR IN GAMMAL1 CALCULATION .5
034547,000201: # Q21 FACTOR IN Q2 CALCULATION. 1000 NM
034548,000202: # Q22 FACTOR IN Q2 CALCULATION. -1302 NM
034549,000203: # VFINAL1 VELOCITY TO START FINAL PHASE ON INITIAL ENTRY 27000 FPS
034550,000204: # VFINAL FACTOR IN INITIAL UP-DOWN CALC 26600 FPS
034551,000205: # VLMIN MINIMUM VL 18000 FPS
034552,000206: # VMIN VELOCITY TO SWITCH TO RELATIVE VEL VSAT/2
034553,000207: # VRCONTRL RDOT TO START INTO HUNTEST 700 FPS
034554,000208: # VRCONT = COMPUTER NAME
034555,000209: # 25NM TOLERANCE TO STOP RANGE ITERATION 25 NM
034556,000210: # VQUIT VELOCITY TO STOP STEERING 1000 FPS
034557,000211:
034558,000212: # # Page 793
034559,000213: # CONVERSION FACTORS AND SCALING CONSTANTS
034560,000214: # ---------- ------- --- ------- ---------
034561,000215:
034562,000216: # ATK ANGLE IN RAD TO NM 3437.7468 NM/RAD
034563,000217: # G5 NOMINAL G VALUE FOR SCALING 32.2 FPSS
034564,000218: # H5 ATMOSPHERE SCALE HEIGHT 28500 FT
034565,000219: # J GRAVITY HARMONIC COEFFICIENT .00162346
034566,000220: # KWE EQUATORIAL EARTH RATE 1546.70168 FPS
034567,000221: # MUE EARTH GRAVITATIONAL CONSTANT 3.986032233 E 14 CUBIC M/ SEC SEC
034568,000222: # RE EARTH RADIUS 21202900 FT
034569,000223: # REQ EARTH EQUATORIAL RADIUS 20925738.2 FT
034570,000224: # VSAT SATELLITE VELOCITY AT RE 25766.1973 FPS
034571,000225: # WIE EARTH RATE .0000729211505 RAD/SEC
034572,000226:
034573,000227: # (END GSOP AS-276, VOL 1, FIG. 5.6-3 CONSTANTS,GAINS, ETC.)
034574,000228:
034575,000229:
034576,000230: # DISPLAY QUANTITIES
034577,000231: # ------------------
034578,000232:
034579,000233: # (SEE SECTION 4 OF THE GSOP FOR SIGN CONVENTIONS. )
034580,000234:
034581,000235: # VARIABLE DESCRIPTION MAXIMUM VALUE
034582,000236: # -------- ----------- ------- -----
034583,000237:
034584,000238: # QMAX PREDICTED MAXIMUM ENTRY ACCEL 163.84 GS N 60
034585,000239: # VPRED PREDICTED VELOCITY AT ALTITUDE 128 M/CENTISEC N 60
034586,000240: # 400K FT ABOVE FISCHER RADIUS.
034587,000241: # GAMMAEI PREDICTED GAMMA AT ALTITUDE 1 REVOLUTION N 60
034588,000242: # 400K FT ABOVE FISCHER RADIUS.
034589,000243: # D DRAG ACCELERATION 805 FPSS N 64
034590,000244: # VMAGI INERTIAL VELOCITY MAGNITUDE 128 M/CENTISEC N 64, N 68
034591,000245: # THETAH DESIRED RANGE ANGLE NM 1 REVOLUTION N 64, N 67
034592,000246: # LAT PRESENT LATITUDE 1 REVOLUTION N 67
034593,000247: # LONG PRESENT LONGITUDE 1 REVOLUTION N 67
034594,000248: # RTOGO RANGE ANGLE TO SPLASH FROM 1 REVOLUTION N 63
034595,000249: # EMSALT FT ABOVE FISCHER RADIUS. (IN NM)
034596,000250: # VIO PREDICTED VELOCITY AT ALTITUDE 128 M/CENTISEC N 63
034597,000251: # EMSALT FT ABOVE FISCHER RADIUS.
034598,000252: # TTE TIME OF FREE FALL TO ALT B 28 CENTISEC N 63
034599,000253: # EMSALT FT ABOVE FISCHER RADIUS.
034600,000254: # ROLLC ROLL COMMAND 1 REVOLUTION N 68, N 68, N 69
034601,000255: # LATANG CROSS-RANGE ERROR (XRNGERR) 4 RADIANS N 66
034602,000256: # DNRNGERR DOWN RANGE ERROR 1 REVOLUTION N 66
034603,000257: # (PREDANG - THETAH IN NM)
034604,000258: # HDOT ALTITUDE RATE 128 M/CENTISEC N 68
034605,000259: # Q7 MINIMUM DRAG FOR UPCONTROL 805 FPSS N 69
034606,000260: # VL EXIT VELOCITY FOR UP-CONTROL 2 VSAT N 69
034607,000261:
034608,000262: # # Page 794
034609,000263: # BODY ATTITUDE QUANTITIES (CM/POSE)
034610,000264: # -----------------------------------
034611,000265:
034612,000266: # VARIABLE DESCRIPTION MAXIMUM VALUE
034613,000267: # -------- ----------- ------- -----
034614,000268:
034615,000269: # -
034616,000270: # -VREL NEGATIVE VELOCITY REL TO ATMOS. 2 VSAT
034617,000271: # -
034618,000272: # OLDUYA USED FOR UYA BELOW 1000 FPS 2
034619,000273: # -
034620,000274: # UXA/2 UNIT VECTOR TRIAD 2
034621,000275: # -
034622,000276: # UYA/2 BASED ON 2
034623,000277: # -
034624,000278: # UZA/2 THE TRAJECTORY. 2
034625,000279: # -
034626,000280: # UBX/2 UNIT VECTOR 2
034627,000281: # -
034628,000282: # UBY/2 BODY TRIAD 2
034629,000283: # -
034630,000284: # UBZ/2 FOR CM. 2
End of include-file ENTRY_LEXICON.agc. Parent file is MAIN.agc