Source Code
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This is the source-code for the Apollo 9 Command Module's Guidance Computer.
These files were derived originally from the scan from MIT's Dibner Institute's
now-discontinued website titled "History of Recent Science and Technology", which
in turn was originally created by Gary Neff, though his high-quality scans were
unfortunately reduced in legibility when presented online.
The markings on the front of the
printout imply that it was the original AGC developer Norm Brodeur's copy.
A scan by Ron Burkey has superceded it, made from a more-legible copy from the collection of original
AGC developer Fred Martin. The source code was transcribed from
those images by Ron Burkey. Note that the page images
presented online are of reduced quality, and that higher-quality 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:ASSEMBLE REVISION 249 OF AGC PROGRAM COLOSSUS BY NASA 2021111-041 20'35 OCT. 28,1968Note that the date is the date of the printout, not the date of the program revision. |
017955,000002: ## Copyright: Public domain.
017956,000003: ## Filename: KALCMANU_STEERING.agc
017957,000004: ## Purpose: Part of the source code for Colossus, build 249.
017958,000005: ## It is part of the source code for the Command Module's (CM)
017959,000006: ## Apollo Guidance Computer (AGC), for Apollo 9.
017960,000007: ## Assembler: yaYUL
017961,000008: ## Reference: pp. 407-412.
017962,000009: ## Contact: Ron Burkey <info@sandroid.org>.
017963,000010: ## Website: www.ibiblio.org/apollo.
017964,000011: ## Mod history: 08/10/04 RSB. Began adapting from corresponding Luminary131
017965,000012: ## source file.
017966,000013: ## 2017-01-06 RSB Page numbers now agree with those on the
017967,000014: ## original harcopy, as opposed to the PDF page
017968,000015: ## numbers in 1701.pdf.
017969,000016: ## 2017-01-15 RSB Cross-diff'd comment text (not whitespace)
017970,000017: ## vs the already-proofed corresponding Colossus
017971,000018: ## 237 and Comanche 55 source-code files
017972,000019: ## and corrected errors found. No differences
017973,000020: ## remained afterward.
017974,000021: ## 2017-01-28 RSB WTIH -> WITH.
017975,000022: ##
017976,000023: ## The contents of the "Colossus249" files, in general, are transcribed
017977,000024: ## from a scanned copy of the program listing. Notations on this
017978,000025: ## document read, in part:
017979,000026: ##
017980,000027: ## Assemble revision 249 of AGC program Colossus by NASA
017981,000028: ## 2021111-041. October 28, 1968.
017982,000029: ##
017983,000030: ## This AGC program shall also be referred to as
017984,000031: ## Colossus 1A
017985,000032: ##
017986,000033: ## Prepared by
017987,000034: ## Massachusetts Institute of Technology
017988,000035: ## 75 Cambridge Parkway
017989,000036: ## Cambridge, Massachusetts
017990,000037: ## under NASA contract NAS 9-4065.
017991,000038: ##
017992,000039: ## Refer directly to the online document mentioned above for further information.
017993,000040: ## Please report any errors (relative to the scanned pages) to info@sandroid.org.
017994,000041: ##
017995,000042: ## In some cases, where the source code for Luminary 131 overlaps that of
017996,000043: ## Colossus 249, this code is instead copied from the corresponding Luminary 131
017997,000044: ## source file, and then is proofed to incorporate any changes.
017998,000045:
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Page 407 |
018000,000047: # GENERATION OF STEERING COMMANDS FOR DIGITAL AUTOPILOT FREE FALL MANEUVERS
018001,000048:
018002,000049: # NEW COMMANDS WILL BE GENERATED EVERY ONE SECOND DURING THE MANEUVER
018003,000050:
018004,000051: 15,2000 BANK 15
018005,000052: 22,2000 SETLOC KALCMON1
018006,000053: 22,2000 BANK
018007,000054:
018008,000055: 22,3027 E6,1661 EBANK= BCDU
018009,000056:
018010,000057: 22,3027 COUNT 22/KALC
018011,000058:
018012,000059: 22,3027 41332 NEWDELHI CS HOLDFLAG # SEE IF MANEUVER HAS BEEN INTERRUPTED
018013,000060: 22,3030 00006 EXTEND # BY ASTRONAUT
018014,000061: 22,3031 62725 BZMF NOGO -2 # IF SO, TERMINATE KALCMANU
018015,000062: 22,3032 06006 NEWANGL TC INTPRET
018016,000063: 22,3033 75160 AXC,1 AXC,2
018017,000064: 22,3034 03320 MIS # COMPUTE THE NEW MATRIX FROM S/C TO
018018,000065: 22,3035 03425 DEL # STABLE MEMBER AXES
018019,000066: 22,3036 77624 CALL
018020,000067: 22,3037 44304 MXM3
018021,000068: 22,3040 45575 VLOAD STADR
018022,000069: 22,3041 50442 STOVL MIS +12D # CALCULATE NEW DESIRED CDU ANGLES
018023,000070: 22,3042 77626 STADR
018024,000071: 22,3043 50450 STOVL MIS +6D
018025,000072: 22,3044 77626 STADR
018026,000073: 22,3045 74456 STORE MIS
018027,000074: 22,3046 45160 AXC,1 CALL
018028,000075: 22,3047 03320 MIS
018029,000076: 22,3050 44655 DCMTOCDU # PICK UP THE NEW CDU ANGLES FROM MATRIX
018030,000077: 22,3051 77634 RTB
018031,000078: 22,3052 45547 V1STO2S
018032,000079: 22,3053 03267 STORE NCDU # NEW CDU ANGLES
018033,000080: 22,3054 77414 BONCLR EXIT
018034,000081: 22,3055 01215 CALCMAN2
018035,000082: 22,3056 45142 MANUSTAT # TO START MANEUVER
018036,000083: 22,3057 34711 CAF TWO # +0 OTHERWISE
018037,000084: 22,3060 55664 INCRDCDU TS KSPNDX
018038,000085: 22,3061 60000 DOUBLE
018039,000086: 22,3062 55665 TS KSPNDX +1
018040,000087: 22,3063 51664 INDEX KSPNDX
018041,000088: 22,3064 31666 CA NCDU # NEW DESIRED CDU ANGLES
018042,000089: 22,3065 00006 EXTEND
018043,000090: 22,3066 51664 INDEX KSPNDX
018044,000091: 22,3067 21661 MSU BCDU # INITIAL S/C ANGLE OR PREVIOUS DESIRED
018045,000092: 22,3070 00006 EXTEND # CDU ANGLES
018046,000093: 22,3071 73141 MP DT/TAU
018047,000094: 22,3072 51665 INDEX KDPNDX
018048,000095: 22,3073 53576 DXCH DELCDUX # ANGLE INCREMENTS TO BE ADDED TO
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Page 408 |
018050,000097: 22,3074 51664 INDEX KSPNDX # DCDU EVERY TENTH SEC
018051,000098: 22,3075 31666 CA NCDU # BY LEM DAP
018052,000099: 22,3076 51664 INDEX KSPNDX
018053,000100: 22,3077 57661 XCH BCDU
018054,000101: 22,3100 51665 INDEX KSPNDX +1
018055,000102: 22,3101 55646 TS CDUXD
018056,000103: 22,3102 11664 CCS KSPNDX
018057,000104: 22,3103 13060 TCF INCRDCDU # LOOP FOR THREE AXES
018058,000105:
018059,000106: 22,3104 00003 RELINT
018060,000107:
018061,000108: # COMPARE PRESENT TIME WITH TIME TO TERMINATE MANEUVER
018062,000109:
018063,000110: 22,3105 03115 TMANUCHK TC TIMECHK
018064,000111: 22,3106 13206 TCF CONTMANU
018065,000112: 22,3107 34712 CAF ONE
018066,000113: 22,3110 05140 MANUSTAL TC WAITLIST
018067,000114: 22,3111 E6,1661 EBANK= BCDU
018068,000115: 22,3111 03232 44106 2CADR MANUSTOP
018069,000116:
018070,000117: 22,3113 00003 RELINT
018071,000118: 22,3114 15112 TCF ENDOFJOB
018072,000119:
018073,000120: 22,3115 00006 TIMECHK EXTEND
018074,000121: 22,3116 40025 DCS TIME2
018075,000122: 22,3117 53673 DXCH TTEMP
018076,000123: 22,3120 00006 EXTEND
018077,000124: 22,3121 31717 DCA TM
018078,000125: 22,3122 21673 DAS TTEMP
018079,000126: 22,3123 11672 CCS TTEMP
018080,000127: 22,3124 00002 TC Q
018081,000128: 22,3125 13127 TCF +2
018082,000129: 22,3126 13137 TCF 2NDRETRN
018083,000130: 22,3127 11673 CCS TTEMP +1
018084,000131: 22,3130 00002 TC Q
018085,000132: 22,3131 13133 TCF MANUOFF
018086,000133: 22,3132 40000 COM
018087,000134: 22,3133 63205 MANUOFF AD ONESEC +1
018088,000135: 22,3134 00006 EXTEND
018089,000136: 22,3135 63137 BZMF 2NDRETRN
018090,000137: 22,3136 24002 INCR Q
018091,000138: 22,3137 24002 2NDRETRN INCR Q
018092,000139: 22,3140 00002 TC Q
018093,000140:
018094,000141: 22,3141 03146 DT/TAU DEC .1
018095,000142:
018096,000143: 22,3142 77776 MANUSTAT EXIT # INITIALIZATION ROUTINE
018097,000144: 22,3143 00006 EXTEND # FOR AUTOMATIC MANEUVERS
018098,000145: 22,3144 30025 DCA TIME2
018099,000146: 22,3145 21717 DAS TM # TM+T0 MANEUVER COMPLETION TIME
018100,000147: 22,3146 00006 EXTEND
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Page 409 |
018102,000149: 22,3147 43205 DCS ONESEC
018103,000150: 22,3150 21717 DAS TM # (TM+T0)-1
018104,000151: 22,3151 00004 INHINT
018105,000152: 22,3152 44712 CS ONE # ENABLE AUTOPILOT TO PERFORM
018106,000153: 22,3153 55332 TS HOLDFLAG # AUTOMATIC MANEUVERS
018107,000154: 22,3154 41130 CS RATEINDX # SEE IF MANEUVERING AT HIGH RATE
018108,000155: 22,3155 66211 AD SIX
018109,000156: 22,3156 00006 EXTEND
018110,000157: 22,3157 63161 BZMF HIGHGAIN
018111,000158: 22,3160 13164 TCF +4
018112,000159: 22,3161 41501 HIGHGAIN CS RCSFLAGS # IF SO, SET HIGH RATE FLAG (BIT 15 OF
018113,000160: 22,3162 74674 MASK BIT15 # RCSFLAGS)
018114,000161: 22,3163 27501 ADS RCSFLAGS
018115,000162: 22,3164 53711 DXCH BRATE # X-AXIS MANEUVER RATE
018116,000163: 22,3165 53526 DXCH WBODY
018117,000164: 22,3166 53713 DXCH BRATE +2 # Y-AXIS MANEUVER RATE
018118,000165: 22,3167 53530 DXCH WBODY1
018119,000166: 22,3170 53715 DXCH BRATE +4 # Z-AXIS MANEUVER RATE
018120,000167: 22,3171 53532 DXCH WBODY2
018121,000168: 22,3172 31675 CA BIASTEMP +1 # INSERT ATTITUDE ERROR BIASES
018122,000169: 22,3173 55564 TS BIAS # INTO AUTOPILOT
018123,000170: 22,3174 31677 CA BIASTEMP +3
018124,000171: 22,3175 55565 TS BIAS1
018125,000172: 22,3176 31701 CA BIASTEMP +5
018126,000173: 22,3177 55566 TS BIAS2
018127,000174: 22,3200 30025 CA TIME1
018128,000175: 22,3201 63205 AD ONESEC +1
018129,000176: 22,3202 57671 XCH NEXTIME
018130,000177: 22,3203 13057 TCF INCRDCDU -1
018131,000178:
018132,000179: 22,3204 00000 ONESEC DEC 0 B-14
018133,000180: 22,3205 00144 DEC 100 B-14
018134,000181:
018135,000182: 22,3206 00004 CONTMANU INHINT
018136,000183: 22,3207 40025 CS TIME1 # CONTINUE WITH UPDATE PROCESS
018137,000184: 22,3210 61671 AD NEXTIME
018138,000185: 22,3211 10000 CCS A
018139,000186: 22,3212 64712 AD ONE
018140,000187: 22,3213 13216 TCF MANUCALL
018141,000188: 22,3214 64674 AD NEGMAX
018142,000189: 22,3215 40000 COM
018143,000190: 22,3216 05140 MANUCALL TC WAITLIST
018144,000191: 22,3217 E6,1661 EBANK= BCDU
018145,000192: 22,3217 03225 44106 2CADR UPDTCALL
018146,000193: 22,3221 00003 RELINT
018147,000194: 22,3222 33205 CAF ONESEC +1 # INCREMENT TIME FOR NEXT UPDATE
018148,000195: 22,3223 27671 ADS NEXTIME
018149,000196: 22,3224 15112 TCF ENDOFJOB
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Page 410 |
018151,000198:
018152,000199: 22,3225 37663 UPDTCALL CAF PRIO26 # CALL FOR UPDATE
018153,000200: 22,3226 05042 TC FINDVAC # OF STEERING COMMANDS
018154,000201: 22,3227 E6,1661 EBANK= BCDU
018155,000202: 22,3227 03027 44106 2CADR NEWDELHI
018156,000203:
018157,000204: 22,3231 05213 TC TASKOVER
018158,000205:
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Page 411 |
018160,000207: # ROUTINE FOR TERMINATING AUTOMATIC MANEUVERS
018161,000208:
018162,000209: 22,3232 03256 MANUSTOP TC STOPYZ
018163,000210: 22,3233 03303 TC LOADYZ
018164,000211:
018165,000212: 22,3234 31155 ENDROLL CA CPHI
018166,000213: 22,3235 55646 TS CDUXD # SET CDUXD TO THE COMMANDED OUTER GIMBAL
018167,000214: 22,3236 03245 TC STOPRATE
018168,000215: 22,3237 31327 ENDMANU CA ATTPRIO # RESTORE USERS PRIORITY
018169,000216: 22,3240 54063 TS NEWPRIO
018170,000217:
018171,000218: 22,3241 34714 CA ZERO # ZERO ATTCADR
018172,000219: 22,3242 53326 DXCH ATTCADR
018173,000220:
018174,000221: 22,3243 05053 TC SPVAC # RETURN TO USER OF GOMANUR
018175,000222:
018176,000223: 22,3244 05213 TC TASKOVER
018177,000224:
018178,000225: 22,3245 34714 STOPRATE CAF ZERO
018179,000226: 22,3246 55575 TS DELCDUX
018180,000227: 22,3247 55576 TS DELCDUX +1 # ZERO ROLL INCREMENTAL ANGLES
018181,000228: 22,3250 55525 TS WBODY # RATE
018182,000229: 22,3251 55526 TS WBODY +1
018183,000230: 22,3252 55564 TS BIAS # BIAS
018184,000231:
018185,000232: 22,3253 44674 CS BIT15 # MAKE SURE HIGH RATE FLAG (BIT 15 OF
018186,000233: 22,3254 71501 MASK RCSFLAGS # RCSFLAGS) IS RESET.
018187,000234: 22,3255 55501 TS RCSFLAGS
018188,000235:
018189,000236: 22,3256 34714 STOPYZ CAF ZERO
018190,000237: 22,3257 55577 TS DELCDUY # ZERO PITCH, YAW
018191,000238: 22,3260 55600 TS DELCDUY +1 # INCREMENTAL ANGLES
018192,000239: 22,3261 55601 TS DELCDUZ
018193,000240: 22,3262 55602 TS DELCDUZ +1
018194,000241: 22,3263 55527 TS WBODY1 # RATES
018195,000242: 22,3264 55530 TS WBODY1 +1
018196,000243: 22,3265 55531 TS WBODY2
018197,000244: 22,3266 55532 TS WBODY2 +1
018198,000245: 22,3267 55565 TS BIAS1 # BIASES
018199,000246: 22,3270 55566 TS BIAS2
018200,000247: 22,3271 00002 TC Q
018201,000248:
018202,000249: 22,3272 30032 ZEROERROR CA CDUX # PICK UP CDU ANGLES AND STORE IN
018203,000250: 22,3273 55646 TS CDUXD # CDU DESIRED
018204,000251: 22,3274 30033 CA CDUY
018205,000252: 22,3275 55650 TS CDUYD
018206,000253: 22,3276 30034 CA CDUZ
018207,000254: 22,3277 55652 TS CDUZD
018208,000255: 22,3300 00002 TC Q
018209,000256:
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Page 412 |
018211,000258: 22,3301 31155 LOADCDUD CA CPHI # STORE TERMINAL ANGLES INTO
018212,000259: 22,3302 55646 TS CDUXD # COMMAND ANGLES
018213,000260: 22,3303 31156 LOADYZ CA CTHETA
018214,000261: 22,3304 55650 TS CDUYD
018215,000262: 22,3305 31157 CA CPSI
018216,000263: 22,3306 55652 TS CDUZD
018217,000264: 22,3307 00002 TC Q
018218,000265:
End of include-file KALCMANU_STEERING.agc. Parent file is MAIN.agc