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 |
032220,000002: # Copyright: Public domain.
032221,000003: # Filename: LUNAR_AND_SOLAR_EPHEMERIDES_SUBROUTINES.agc
032222,000004: # Purpose: Part of the source code for Colossus build 237.
032223,000005: # This is for the Command Module's (CM) Apollo Guidance
032224,000006: # Computer (AGC), we believe for Apollo 8.
032225,000007: # Assembler: yaYUL
032226,000008: # Contact: Jim Lawton <jim DOT lawton AT gmail DOT com>
032227,000009: # Website: www.ibiblio.org/apollo/index.html
032228,000010: # Page scans: www.ibiblio.org/apollo/ScansForConversion/Colossus237/
032229,000011: # Mod history: 2011-02-27 JL Adapted from corresponding Colossus 249 file.
032230,000012:
032231,000013: # # Page 736
032232,000014: # LUNAR AND SOLAR EPHEMERIDES SUBROUTINES
032233,000015:
032234,000016: # FUNCTIONAL DESCRIPTION
032235,000017:
032236,000018: # THESE SUBROUTINES ARE USED TO DETERMINE THE POSITION AND VELOCITY
032237,000019: # VECTORS OF THE SUN AND THE MOON RELATIVE TO THE EARTH AT THE
032238,000020: # SPECIFIED GROUND ELAPSED TIME INPUT BY THE USER.
032239,000021:
032240,000022: # THE POSITION OF THE MOON IS STORED IN THE COMPUTER IN THE FORM OF
032241,000023: # A NINTH DEGREE POLYNOMIAL APPROXIMATION WHICH IS VALID OVER A 15
032242,000024: # DAY INTERVAL BEGINNING SHORTLY BEFORE LAUNCH. THEREFORE THE TIME
032243,000025: # INPUT BY THE USER SHOULD FALL WITHIN THIS 15 DAY INTERVAL.
032244,000026:
032245,000027: # LSPOS COMPUTES THE POSITION VECTORS OF THE SUN AND THE MOON.
032246,000028:
032247,000029: # LUNPOS COMPUTES THE POSITION VECTOR OF THE MOON.
032248,000030:
032249,000031: # LUNVEL COMPUTES THE VELOCITY VECTOR OF THE MOON.
032250,000032:
032251,000033: # SOLPOS COMPUTES THE POSITION VECTOR OF THE SUN.
032252,000034:
032253,000035: # CALLING SEQUENCE
032254,000036:
032255,000037: # DLOAD CALL
032256,000038: # TIME GROUND ELAPSED TIME
032257,000039: # SUBROUTINE LSPOS OR LUNPOS OR LUNVEL OR SOLPOS
032258,000040:
032259,000041: # INPUT
032260,000042:
032261,000043: # 1) SPECIFIED GROUND ELAPSED TIME IN CS X B-28 LOADED IN MPAC.
032262,000044:
032263,000045: # 2) TIMEMO - TIME AT THE CENTER OF THE RANGE OVER WHICH THE LUNAR
032264,000046: # POSITION POLYNOMIAL IS VALID IN CS X B-42.
032265,000047:
032266,000048: # 3) VECOEM - VECTOR COEFFICIENTS OF THE LUNAR POSITION POLYNOMIAL
032267,000049: # LOADED IN DESCENDING SEQUENCE IN METERS/CS**N X B-2
032268,000050:
032269,000051: # 4) RESO - POSITION VECTOR OF THE SUN RELATIVE TO THE EARTH AT
032270,000052: # TIMEMO IN METERS X B-38.
032271,000053:
032272,000054: # 5) VESO - VELOCITY VECTOR OF THE SUN RELATIVE TO THE EARTH AT
032273,000055: # TIMEMO IN METERS/CS X B-9.
032274,000056:
032275,000057: # 6) OMEGAES - ANGULAR VELOCITY OF THE VECTOR RESO AT TIMEMO IN
032276,000058: # REV/CS X B+26.
032277,000059:
032278,000060: # ALL EXCEPT THE FIRST INPUT ARE INCLUDED IN THE PRE-LAUNCH
032279,000061: # ERASABLE DATA LOAD.
032280,000062:
032281,000063: # OUTPUT - LSPOS
032282,000064: # # Page 737
032283,000065: # 1) 2D OF VAC AREA CONTAINS THE POSITION VECTOR OF THE SUN RELATIVE
032284,000066: # TO THE EARTH AT TIME INPUT BY THE USER IN METERS X B-38.
032285,000067:
032286,000068: # 2) MPAC CONTAINS THE POSITION VECTOR OF THE MOON RELATIVE TO THE
032287,000069: # EARTH AT TIME INPUT BY THE USER IN METERS X B-29.
032288,000070:
032289,000071: # OUTPUT - LUNPOS
032290,000072:
032291,000073: # MPAC CONTAINS THE POSITION VECTOR OF THE MOON RELATIVE TO THE
032292,000074: # EARTH AT THE TIME INPUT BY USER IN METERS X B-29.
032293,000075:
032294,000076: # OUTPUT - LUNVEL
032295,000077:
032296,000078: # MPAC CONTAINS THE VELOCITY VECTOR OF THE MOON RELATIVE TO THE
032297,000079: # EARTH AT THE TIME INPUT BY THE USER IN METERS/CS X B-7.
032298,000080:
032299,000081: # OUTPUT - SOLPOS
032300,000082:
032301,000083: # MPAC CONTAINS THE POSITION VECTOR OF THE SUN RELATIVE TO THE EARTH
032302,000084: # AT TIME INPUT BY THE USER IN METERS X B-38.
032303,000085:
032304,000086: # SUBROUTINES USED
032305,000087:
032306,000088: # NONE
032307,000089:
032308,000090: # REMARKS
032309,000091:
032310,000092: # THE VAC AREA IS USED FOR STORAGE OF INTERMEDIATE AND FINAL RESULTS
032311,000093: # OF COMPUTATIONS.
032312,000094:
032313,000095: # S1, X1 AND X2 ARE USED BY THESE SUBROUTINES.
032314,000096: # PRELAUNCH ERASABLE DATA LOAD ARE ONLY ERASABLE STORAGE USED BY
032315,000097: # THESE SUBROUTINES.
032316,000098: # RESTARTS DURING OPERATION OF THESE SUBROUTINES MUST BE HANDLED BY
032317,000099: # THE USER.
032318,000100:
032319,000101: 36,2502 BANK 36
032320,000102: 26,2000 SETLOC EPHEM
032321,000103: 26,2000 BANK
032322,000104:
032323,000105: 26,2110 COUNT* $$/EPHEM
032324,000106: 26,2110 0003777 EBANK= END-E7
032325,000107: 26,2110 77774 LSPOS AXT,2 # COMPUTES POSITION VECTORS OF BOTH THE
032326,000108: 26,2111 54161 RESA # SUN AND THE MOON. THE POSITION VECTOR
032327,000109: 26,2112 52170 AXT,1 GOTO # OF THE SUN IS STORED IN 2D OF THE VAC
032328,000110: 26,2113 54143 RES # AREA. THE POSITION VECTOR OF THE MOON
032329,000111: 26,2114 54126 LSTIME # IS STORED IN MPAC.
032330,000112: 26,2115 52170 LUNPOS AXT,1 GOTO # COMPUTES THE POSITION VECTOR OF THE MOON
032331,000113: 26,2116 54162 REM # AND STORES IT IN MPAC.
032332,000114: 26,2117 54126 LSTIME
032333,000115: # # Page 738
032334,000116: 26,2120 52170 LUNVEL AXT,1 GOTO # COMPUTES THE VELOCITY VECTOR OF THE MOON
032335,000117: 26,2121 54173 VEM # AND STORES IT IN MPAC.
032336,000118: 26,2122 54126 LSTIME
032337,000119: 26,2123 76020 SOLPOS STQ AXT,1 # COMPUTES THE POSITION VECTOR OF THE SUN
032338,000120: 26,2124 00047 X2 # AND STORES IT IN MPAC.
032339,000121: 26,2125 54143 RES
032340,000122: 26,2126 54201 LSTIME SETPD SR
032341,000123: 26,2127 00001 0D
032342,000124: 26,2130 20617 14D
032343,000125: 26,2131 57571 TAD DCOMP
032344,000126: 26,2132 01707 TEPHEM
032345,000127: 26,2133 57571 TAD DCOMP
032346,000128: 26,2134 02034 TIMEMO
032347,000129: 26,2135 66261 SL SSP
032348,000130: 26,2136 20221 16D
032349,000131: 26,2137 00051 S1
032350,000132: 26,2140 00006 6D
032351,000133: 26,2141 77650 GOTO
032352,000134: 26,2142 00046 X1
032353,000135: 26,2143 41206 RES PUSH DMP # PD- 2
032354,000136: 26,2144 02147 OMEGAES
032355,000137: 26,2145 71406 PUSH COS # PD- 4
032356,000138: 26,2146 65361 VXSC PDDL # PD- 8
032357,000139: 26,2147 02133 RESO
032358,000140: 26,2150 63356 SIN PDVL # PD-10
032359,000141: 26,2151 02133 RESO
032360,000142: 26,2152 53406 PUSH UNIT # PD-16
032361,000143: 26,2153 53435 VXV UNIT
032362,000144: 26,2154 02141 VESO
032363,000145: 26,2155 76435 VXV VSL1 # PD-10
032364,000146: 26,2156 53361 VXSC VAD # PD-02
032365,000147: 26,2157 52172 VSL1 GOTO # RES IN METERS X B-38 IN MPAC.
032366,000148: 26,2160 00047 X2
032367,000149: 26,2161 14003 RESA STODL 2D # RES IN METERS X B-38 IN 2D OF VAC. PD- 0
032368,000150: 26,2162 63370 REM AXT,1 PDVL # PD- 2
032369,000151: 26,2163 00066 54D
032370,000152: 26,2164 02037 VECOEM
032371,000153: 26,2165 52761 REMA VXSC VAD*
032372,000154: 26,2166 00001 0D
032373,000155: 26,2167 02133 VECOEM +60D,1
032374,000156: 26,2170 72500 TIX,1 VSL2 # REM IN METERS X B-29 IN MPAC.
032375,000157: 26,2171 54165 REMA
032376,000158: 26,2172 77616 RVQ
032377,000159: 26,2173 65370 VEM AXT,1 PDDL # PD- 2
032378,000160: 26,2174 00060 48D
032379,000161: 26,2175 14214 NINEB4
032380,000162: 26,2176 74206 PUSH VXSC # PD- 4
032381,000163: 26,2177 02037 VECOEM
032382,000164: 26,2200 77761 VEMA VXSC
032383,000165: 26,2201 00001 0D
032384,000166: # # Page 739
032385,000167: 26,2202 14005 STODL 4D # PD- 2
032386,000168: 26,2203 41425 DSU PUSH # PD- 4
032387,000169: 26,2204 14216 ONEB4
032388,000170: 26,2205 53357 VXSC* VAD
032389,000171: 26,2206 02125 VECOEM +54D,1
032390,000172: 26,2207 00005 4D
032391,000173: 26,2210 72500 TIX,1 VSL2 # VEM IN METERS/CS X B-7 IN MPAC.
032392,000174: 26,2211 54200 VEMA
032393,000175: 26,2212 77616 RVQ
032394,000176: 26,2213 22000 00000 NINEB4 2DEC 9.0 B-4
032395,000177: 26,2215 02000 00000 ONEB4 2DEC 1.0 B-4
End of include-file LUNAR_AND_SOLAR_EPHEMERIDES_SUBROUTINES.agc. Parent file is MAIN.agc