GAP: ASSEMBLE REVISION 055 OF AGC PROGRAM COMANCHE BY NASA 2021113-051 10:28 APR. 1,1969Note that the date is the date of the printout, not the date of the program revision.
Source Code
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These source-code files were from the printout at the MIT Museum, with many thanks
to Deborah Douglas, the Museum's Curator of Science and Technology, for releasing
it to us. The printout was digitally photographed by Paul Fjeld. A team of
volunteers transcribed the source code manually from these images or, where
appropriate, modified already-transcribed but similar source Colossus 249 (Apollo 9)
source code to agree with the images from the printout. 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:GAP: ASSEMBLE REVISION 055 OF AGC PROGRAM COMANCHE BY NASA 2021113-051 10:28 APR. 1,1969Note that the date is the date of the printout, not the date of the program revision. |
035068,000002: ## Copyright: Public domain.
035069,000003: ## Filename: LUNAR_AND_SOLAR_EPHEMERIDES_SUBROUTINES.agc
035070,000004: ## Purpose: Part of the source code for Comanche, build 055. It
035071,000005: ## is part of the source code for the Command Module's
035072,000006: ## (CM) Apollo Guidance Computer (AGC), Apollo 11.
035073,000007: ## Assembler: yaYUL
035074,000008: ## Reference: pp. 785-788
035075,000009: ## Contact: Ron Burkey <info@sandroid.org>
035076,000010: ## Website: http://www.ibiblio.org/apollo.
035077,000011: ## Mod history: 2009-05-12 RSB Adapted from Colossus249 file of the same
035078,000012: ## name and Comanche 055 page images.
035079,000013: ## 2009-07-26 RSB Added annotations related to computation
035080,000014: ## of the ephemeral(?) polynomials.
035081,000015: ## 2016-12-11 RSB Proofed comments with octopus/ProoferComments
035082,000016: ## and fixed the errors found.
035083,000017: ##
035084,000018: ## The contents of the "Comanche055" files, in general, are transcribed
035085,000019: ## from scanned documents.
035086,000020: ##
035087,000021: ## Assemble revision 055 of AGC program Comanche by NASA
035088,000022: ## 2021113-051. April 1, 1969.
035089,000023: ##
035090,000024: ## This AGC program shall also be referred to as Colossus 2A
035091,000025: ##
035092,000026: ## Prepared by
035093,000027: ## Massachusetts Institute of Technology
035094,000028: ## 75 Cambridge Parkway
035095,000029: ## Cambridge, Massachusetts
035096,000030: ##
035097,000031: ## under NASA contract NAS 9-4065.
035098,000032: ##
035099,000033: ## Refer directly to the online document mentioned above for further
035100,000034: ## information. Please report any errors to info@sandroid.org.
035101,000035:
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Page 785 |
035103,000037: # LUNAR AND SOLAR EPHEMERIDES SUBROUTINES
035104,000038:
035105,000039: # FUNCTIONAL DESCRIPTION
035106,000040:
035107,000041: # THESE SUBROUTINES ARE USED TO DETERMINE THE POSITION AND VELOCITY
035108,000042: # VECTORS OF THE SUN AND THE MOON RELATIVE TO THE EARTH AT THE
035109,000043: # SPECIFIED GROUND ELAPSED TIME INPUT BY THE USER.
035110,000044:
035111,000045: # THE POSITION OF THE MOON IS STORED IN THE COMPUTER IN THE FORM OF
035112,000046: # A NINTH DEGREE POLYNOMIAL APPROXIMATION WHICH IS VALID OVER A 15
035113,000047: # DAY INTERVAL BEGINNING SHORTLY BEFORE LAUNCH. THEREFORE THE TIME
035114,000048: # INPUT BY THE USER SHOULD FALL WITHIN THIS 15 DAY INTERVAL.
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The 9th-degree polynomial spoken of here is a pad load, meaning that it is not actually hardcoded into the software. Additional information about calculating the polynomial can be found on the Orbiter NASSP wiki, as well as information about calculation of the solar ephemerides. |
035122,000056:
035123,000057: # LSPOS COMPUTES THE POSITION VECTORS OF THE SUN AND THE MOON.
035124,000058:
035125,000059: # LUNPOS COMPUTES THE POSITION VECTOR OF THE MOON.
035126,000060:
035127,000061: # LUNVEL COMPUTES THE VELOCITY VECTOR OF THE MOON.
035128,000062:
035129,000063: # SOLPOS COMPUTES THE POSITION VECTOR OF THE SUN.
035130,000064:
035131,000065: # CALLING SEQUENCE
035132,000066:
035133,000067: # DLOAD CALL
035134,000068: # TIME GROUND ELAPSED TIME
035135,000069: # SUBROUTINE LSPOS OR LUNPOS OR LUNVEL OR SOLPOS
035136,000070:
035137,000071: # INPUT
035138,000072:
035139,000073: # 1) SPECIFIED GROUND ELAPSED TIME IN CS X B-28 LOADED IN MPAC.
035140,000074:
035141,000075: # 2) TIMEMO - TIME AT THE CENTER OF THE RANGE OVER WHICH THE LUNAR
035142,000076: # POSITION POLYNOMIAL IS VALID IN CS X B-42.
035143,000077:
035144,000078: # 3) VECOEM - VECTOR COEFFICIENTS OF THE LUNAR POSITION POLYNOMIAL
035145,000079: # LOADED IN DESCENDING SEQUENCE IN METERS/CS**N X B-2
035146,000080:
035147,000081: # 4) RESO - POSITION VECTOR OF THE SUN RELATIVE TO THE EARTH AT
035148,000082: # TIMEMO IN METERS X B-38.
035149,000083:
035150,000084: # 5) VESO - VELOCITY VECTOR OF THE SUN RELATIVE TO THE EARTH AT
035151,000085: # TIMEMO IN METERS/CS X B-9.
035152,000086: #
035153,000087: # 6) OMEGAES - ANGULAR VELOCITY OF THE VECTOR RESO AT TIMEMO IN
035154,000088: # REV/CS X B+26.
035155,000089:
035156,000090: # ALL EXCEPT THE FIRST INPUT ARE INCLUDED IN THE PRE-LAUNCH
035157,000091: # ERASABLE DATA LOAD.
035158,000092:
035159,000093: # OUTPUT - LSPOS
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Page 786 |
035161,000095:
035162,000096: # 1) 2D OF VAC AREA CONTAINS THE POSITION VECTOR OF THE SUN RELATIVE
035163,000097: # TO THE EARTH AT TIME INPUT BY THE USER IN METERS X B-38.
035164,000098:
035165,000099: # 2) MPAC CONTAINS THE POSITION VECTOR OF THE MOON RELATIVE TO THE
035166,000100: # EARTH AT TIME INPUT BY THE USER IN METERS X B-29.
035167,000101:
035168,000102: # OUTPUT - LUNPOS
035169,000103:
035170,000104: # MPAC CONTAINS THE POSITION VECTOR OF THE MOON RELATIVE TO THE
035171,000105: # EARTH AT THE TIME INPUT BY USER IN METERS X B-29.
035172,000106:
035173,000107: # OUTPUT - LUNVEL
035174,000108:
035175,000109: # MPAC CONTAINS THE VELOCITY VECTOR OF THE MOON RELATIVE TO THE
035176,000110: # EARTH AT TIME INPUT BY THE USER IN METERS/CS X B-7.
035177,000111:
035178,000112: # OUTPUT - SOLPOS
035179,000113:
035180,000114: # MPAC CONTAINS THE POSITION VECTOR OF THE SUN RELATIVE TO THE EARTH
035181,000115: # AT TIME INPUT BY THE USER IN METERS X B-38.
035182,000116:
035183,000117: # SUBROUTINES USED
035184,000118:
035185,000119: # NONE
035186,000120:
035187,000121: # REMARKS
035188,000122:
035189,000123: # THE VAC AREA IS USED FOR STORAGE OF INTERMEDIATE AND FINAL RESULTS
035190,000124: # OF COMPUTATIONS.
035191,000125:
035192,000126: # S1, X1 AND X2 ARE USED BY THESE SUBROUTINES.
035193,000127:
035194,000128: # PRELAUNCH ERASABLE DATA LOAD ARE ONLY ERASABLE STORAGE USED BY
035195,000129: # THESE SUBROUTINES.
035196,000130:
035197,000131: # RESTARTS DURING OPERATION OF THESE SUBROUTINES MUST BE HANDLED BY
035198,000132: # THE USER.
035199,000133:
035200,000134: 36,2466 BANK 36
035201,000135: 26,2000 SETLOC EPHEM
035202,000136: 26,2000 BANK
035203,000137:
035204,000138: 26,2110 COUNT* $$/EPHEM
035205,000139: 26,2110 E7,1777 EBANK= END-E7
035206,000140: 26,2110 77774 LSPOS AXT,2 # COMPUTES POSITION VECTORS OF BOTH THE
035207,000141: 26,2111 54161 RESA # SUN AND THE MOON. THE POSITION VECTOR
035208,000142: 26,2112 52170 AXT,1 GOTO # OF THE SUN IS STORED IN 2D OF THE VAC
035209,000143: 26,2113 54143 RES # AREA. THE POSITION VECTOR OF THE MOON
035210,000144: 26,2114 54126 LSTIME # IS STORED IN MPAC.
035211,000145: 26,2115 52170 LUNPOS AXT,1 GOTO # COMPUTES THE POSITION VECTOR OF THE MOON
035212,000146: 26,2116 54162 REM # AND STORES IT IN MPAC.
035213,000147: 26,2117 54126 LSTIME
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Page 787 |
035215,000149: 26,2120 52170 LUNVEL AXT,1 GOTO # COMPUTES THE VELOCITY VECTOR OF THE MOON
035216,000150: 26,2121 54173 VEM # AND STORES IT IN MPAC.
035217,000151: 26,2122 54126 LSTIME
035218,000152: 26,2123 76020 SOLPOS STQ AXT,1 # COMPUTES THE POSITION VECTOR OF THE SUN
035219,000153: 26,2124 00047 X2 # AND STORES IT IN MPAC.
035220,000154: 26,2125 54143 RES
035221,000155: 26,2126 54201 LSTIME SETPD SR
035222,000156: 26,2127 00001 0D
035223,000157: 26,2130 20617 14D
035224,000158: 26,2131 57571 TAD DCOMP
035225,000159: 26,2132 01707 TEPHEM
035226,000160: 26,2133 57571 TAD DCOMP
035227,000161: 26,2134 02034 TIMEMO
035228,000162: 26,2135 66261 SL SSP
035229,000163: 26,2136 20221 16D
035230,000164: 26,2137 00051 S1
035231,000165: 26,2140 00006 6D
035232,000166: 26,2141 77650 GOTO
035233,000167: 26,2142 00046 X1
035234,000168: 26,2143 41206 RES PUSH DMP # PD- 2
035235,000169: 26,2144 02147 OMEGAES
035236,000170: 26,2145 71406 PUSH COS # PD- 4
035237,000171: 26,2146 65361 VXSC PDDL # PD- 8
035238,000172: 26,2147 02133 RESO
035239,000173: 26,2150 63356 SIN PDVL # PD-10
035240,000174: 26,2151 02133 RESO
035241,000175: 26,2152 53406 PUSH UNIT # PD-16
035242,000176: 26,2153 53435 VXV UNIT
035243,000177: 26,2154 02141 VESO
035244,000178: 26,2155 76435 VXV VSL1 # PD-10
035245,000179: 26,2156 53361 VXSC VAD # PD-02
035246,000180: 26,2157 52172 VSL1 GOTO # RES IN METERS X B-38 IN MPAC.
035247,000181: 26,2160 00047 X2
035248,000182: 26,2161 14003 RESA STODL 2D # RES IN METERS X B-38 IN 2D OF VAC. PD- 0
035249,000183: 26,2162 63370 REM AXT,1 PDVL # PD- 2
035250,000184: 26,2163 00066 54D
035251,000185: 26,2164 02037 VECOEM
035252,000186: 26,2165 52761 REMA VXSC VAD*
035253,000187: 26,2166 00001 0D
035254,000188: 26,2167 02133 VECOEM +60D,1
035255,000189: 26,2170 72500 TIX,1 VSL2 # REM IN METERS X B-29 IN MPAC.
035256,000190: 26,2171 54165 REMA
035257,000191: 26,2172 77616 RVQ
035258,000192: 26,2173 65370 VEM AXT,1 PDDL # PD- 2
035259,000193: 26,2174 00060 48D
035260,000194: 26,2175 14214 NINEB4
035261,000195: 26,2176 74206 PUSH VXSC # PD- 4
035262,000196: 26,2177 02037 VECOEM
035263,000197: 26,2200 77761 VEMA VXSC
035264,000198: 26,2201 00001 0D
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Page 788 |
035266,000200: 26,2202 14005 STODL 4D # PD- 2
035267,000201: 26,2203 41425 DSU PUSH # PD- 4
035268,000202: 26,2204 14216 ONEB4
035269,000203: 26,2205 53357 VXSC* VAD
035270,000204: 26,2206 02125 VECOEM +54D,1
035271,000205: 26,2207 00005 4D
035272,000206: 26,2210 72500 TIX,1 VSL2 # VEM IN METERS/CS X B-7 IN MPAC.
035273,000207: 26,2211 54200 VEMA
035274,000208: 26,2212 77616 RVQ
035275,000209: 26,2213 22000 00000 NINEB4 2DEC 9.0 B-4
035276,000210:
035277,000211: 26,2215 02000 00000 ONEB4 2DEC 1.0 B-4
035278,000212:
035279,000213:
035280,000214:
End of include-file LUNAR_AND_SOLAR_EPHEMERIDES_SUBROUTINES.agc. Parent file is MAIN.agc