Source Code
|
This is a reconstructed version of Luminary 130, the initial AGC program released
in November 1969 for the Apollo 13 LM. Three more releases
followed before the flown revision was finally manufactured in February 1970.
This reconstruction was created from a previous transcription of the original listing of
Luminary 131, combined with Luminary memo #129 which describes the small difference
between the Luminary 130 and 131. The reconstructed source code was verified by
matching memory-bank checksums to those listed for Luminary 130 in drawing 2021152G.
In this source code, program comments from the original (Luminary 131) code are
prefixed with '#', while those added later by the Virtual AGC project are prefixed
with '##'.
|
013484,000002: ## Copyright: Public domain.
013485,000003: ## Filename: LEM_GEOMETRY.agc
013486,000004: ## Purpose: A section of the reconstructed source code for Luminary 130.
013487,000005: ## This was the original program released for the Apollo 13 LM,
013488,000006: ## although several more revisions would follow. It has been
013489,000007: ## reconstructed from a listing of Luminary 131, from which it
013490,000008: ## differs on only two lines in P70-P71. The difference is
013491,000009: ## described in detail in Luminary memo #129, which was used
013492,000010: ## to perform the reconstruction. This file is intended to be a
013493,000011: ## faithful reconstruction, except that the code format has been
013494,000012: ## changed to conform to the requirements of the yaYUL assembler
013495,000013: ## rather than the original YUL assembler.
013496,000014: ## Reference: pp. 322-327
013497,000015: ## Contact: Ron Burkey <info@sandroid.org>.
013498,000016: ## Website: www.ibiblio.org/apollo/index.html
013499,000017: ## Mod history: 05/10/03 RSB. Began transcribing.
013500,000018: ## 05/14/05 RSB Corrected website reference above.
013501,000019: ## 2010-08-24 JL Fixed page 330 number.
013502,000020: ## 2017-01-06 RSB Page numbers now agree with those on the
013503,000021: ## original harcopy, as opposed to the PDF page
013504,000022: ## numbers in 1701.pdf.
013505,000023: ## 2017-02-23 RSB Proofed comment text using octopus/ProoferComments.
013506,000024: ## 2017-03-07 RSB Fixed comment-text error noted while proofing
013507,000025: ## Luminary 116.
013508,000026: ## 2018-09-04 MAS Copied from Luminary 131 for Luminary 130.
013509,000027:
|
|
Page 322
|
013511,000029: 23,2041 BANK 23
013512,000030: 13,2000 SETLOC LEMGEOM
013513,000031: 13,2000 BANK
013514,000032:
013515,000033: 13,2070 30,2000 SBANK= LOWSUPER
013516,000034: 13,2070 E5,1642 EBANK= XSM
013517,000035:
013518,000036: # THESE TWO ROUTINES COMPUTE THE ACTUAL STATE VECTOR FOR LM,CSM BY ADDING
013519,000037: # THE CONIC R,V AND THE DEVIATIONS R,V. THE STATE VECTORS ARE CONVERTED TO
013520,000038: # METERS B-29 AND METERS/CSEC B-7 AND STORED APPROPRIATELY IN RN,VN OR
013521,000039: # R-OTHER,V-OTHER FOR DOWNLINK. THE ROUTINES NAMES ARE SWITCHED IN THE
013522,000040: # OTHER VEHICLES COMPUTER.
013523,000041:
013524,000042: # INPUT
013525,000043: # STATE VECTOR IN TEMPORARY STORAGE AREA
013526,000044: # IF STATE VECTOR IS SCALED POS B27 AND VEL B5
013527,000045: # SET X2 TO +2
013528,000046: # IF STATE VECTOR IS SCALED POS B29 AND VEL B7
013529,000047: # SET X2 TO 0
013530,000048:
013531,000049: # OUTPUT
013532,000050: # R(T) IN RN, V(T) IN VN, T IN PIPTIME
013533,000051: # OR
013534,000052: # R(T) IN R-OTHER, V(T) IN V-OTHER (T IS DEFINED BY T-OTHER)
013535,000053:
013536,000054: 13,2070 COUNT* $$/GEOM
013537,000055: 13,2070 43414 SVDWN2 BOF RVQ # SW=1=AVETOMID DOING W-MATRIX INTEG.
013538,000056: 13,2071 04756 AVEMIDSW
013539,000057: 13,2072 26073 +1
013540,000058: 13,2073 53775 VLOAD VSL*
013541,000059: 13,2074 01521 TDELTAV
013542,000060: 13,2075 57605 0 -7,2
013543,000061: 13,2076 53655 VAD VSL*
013544,000062: 13,2077 01535 RCV
013545,000063: 13,2100 57576 0,2
013546,000064: 13,2101 25220 STOVL RN
013547,000065: 13,2102 01527 TNUV
013548,000066: 13,2103 53257 VSL* VAD
013549,000067: 13,2104 57602 0 -4,2
013550,000068: 13,2105 01543 VCV
013551,000069: 13,2106 77657 VSL*
013552,000070: 13,2107 57576 0,2
013553,000071: 13,2110 15226 STODL VN
013554,000072: 13,2111 01517 TET
013555,000073: 13,2112 01234 STORE PIPTIME
013556,000074: 13,2113 77616 RVQ
|
|
Page 323
|
013558,000076: 13,2114 53775 SVDWN1 VLOAD VSL*
013559,000077: 13,2115 01521 TDELTAV
013560,000078: 13,2116 57605 0 -7,2
013561,000079: 13,2117 53655 VAD VSL*
013562,000080: 13,2120 01535 RCV
013563,000081: 13,2121 57576 0,2
013564,000082: 13,2122 25720 STOVL R-OTHER
013565,000083: 13,2123 01527 TNUV
013566,000084: 13,2124 53257 VSL* VAD
013567,000085: 13,2125 57602 0 -4,2
013568,000086: 13,2126 01543 VCV
013569,000087: 13,2127 77657 VSL*
013570,000088: 13,2130 57576 0,2
013571,000089: 13,2131 01726 STORE V-OTHER
013572,000090: 13,2132 77616 RVQ
013573,000091:
|
|
Page 324
|
013575,000093: # THE FOLLOWING ROUTINE TAKES A HALF UNIT TARGET VECTOR REFERRED TO NAV BASE COORDINATES AND FINDS BOTH
013576,000094: # GIMBAL ORIENTATIONS AT WHICH THE RR MIGHT SIGHT THE TARGET. THE GIMBAL ANGLES CORRESPONDING TO THE PRESENT MODE
013577,000095: # ARE LEFT IN MODEA AND THOSE WHICH WOULD BE USED AFTER A REMODE IN MODEB. THIS ROUTINE ASSUMES MODE 1 IS TRUNNION
013578,000096: # ANGLE LESS THAN 90 DEGS IN ABS VALUE WITH ARBITRARY SHAFT, WITH A CORRESPONDING DEFINITION FOR MODE 2. MODE
013579,000097: # SELECTION AND LIMIT CHECKING ARE DONE ELSEWHERE.
013580,000098:
013581,000099: # THE MODE 1 CONFIGURATION IS CALCULATED FROM THE VECTOR AND THEN MODE 2 IS FOUND USING THE RELATIONS
013582,000100:
013583,000101: # S(2) = 180 + S(1)
013584,000102: # T(2) = 180 - T(1)
013585,000103:
013586,000104: # THE VECTOR ARRIVES IN MPAC WHERE TRG*SMNG OR *SMNB* WILL HAVE LEFT IT.
013587,000105:
013588,000106: 13,2133 00041 RRANGLES STORE 32D
013589,000107: 13,2134 57545 DLOAD DCOMP # SINCE WE WILL FIND THE MODE 1 SHAFT
013590,000108: 13,2135 00043 34D # ANGLE LATER, WE CAN FIND THE MODE 1
013591,000109: 13,2136 67401 SETPD ASIN # TRUNNION BY SIMPLY TAKING THE ARCSIN OF
013592,000110: 13,2137 00001 0 # THE Y COMPONENT, THE ASIN GIVING AN
013593,000111: 13,2140 44206 PUSH BDSU # ANSWER WHOSE ABS VAL IS LESS THAN 90 DEG
013594,000112: 13,2141 24005 LODPHALF
013595,000113: 13,2142 14005 STODL 4 # MODE 2 TRUNNION TO 4.
013596,000114: 13,2143 24007 LO6ZEROS
013597,000115: 13,2144 24043 STOVL 34D # UNIT THE PROJECTION OF THE VECTOR
013598,000116: 13,2145 00041 32D # IN THE X-Z PLANE
013599,000117: 13,2146 41056 UNIT BOVB # IF OVERFLOW, TARGET VECTOR IS ALONG Y
013600,000118: 13,2147 52432 LUNDESCH # CALL FOR MANEUVER UNLESS ON LUNAR SURF
013601,000119: 13,2150 14041 STODL 32D # PROJECTION VECTOR.
013602,000120: 13,2151 00041 32D
013603,000121: 13,2152 44142 SR1 STQ
013604,000122: 13,2153 00051 S2
013605,000123: 13,2154 14023 STODL SINTH # USE ARCTRIG SINCE SHAFT COULD BE ARB.
013606,000124: 13,2155 00045 36D
013607,000125: 13,2156 77742 SR1
013608,000126: 13,2157 34021 STCALL COSTH
013609,000127: 13,2160 47322 ARCTRIG
|
|
Page 325
|
013611,000129: 13,2161 43206 PUSH DAD # MODE 1 SHAFT TO 2.
013612,000130: 13,2162 24005 LODPHALF
013613,000131: 13,2163 24007 STOVL 6
013614,000132: 13,2164 00005 4
013615,000133: 13,2165 77634 RTB # FIND MODE 2 CDU ANGLES.
013616,000134: 13,2166 21636 2V1STO2S
013617,000135: 13,2167 25111 STOVL MODEB
013618,000136: 13,2170 00001 0
013619,000137: 13,2171 77634 RTB # MODE 1 ANGLES TO MODE A.
013620,000138: 13,2172 21636 2V1STO2S
013621,000139: 13,2173 01107 STORE MODEA
013622,000140: 13,2174 77776 EXIT
013623,000141:
013624,000142: 13,2175 40110 CS RADMODES # SWAP MODEA AND MODEB IF RR IN MODE 2.
013625,000143: 13,2176 74740 MASK ANTENBIT
013626,000144: 13,2177 10000 CCS A
013627,000145: 13,2200 12204 TCF +4
013628,000146:
013629,000147: 13,2201 53107 DXCH MODEA
013630,000148: 13,2202 53111 DXCH MODEB
013631,000149: 13,2203 53107 DXCH MODEA
013632,000150:
013633,000151: 13,2204 06042 TC INTPRET
013634,000152: 13,2205 77650 GOTO
013635,000153: 13,2206 00051 S2
|
|
Page 326
|
013637,000155: # GIVEN RR TRUNNION AND SHAFT (T,S) IN TANGNB,+1, FIND THE ASSOCIATED
013638,000156: # LINE OF SIGHT IN NAV BASE AXES. THE HALF UNIT VECTOR, .5(SIN(S)COS(T),
013639,000157: # -SIN(T),COS(S)COS(T)) IS LEFT IN MPAC AND 32D.
013640,000158:
013641,000159: 23,2000 SETLOC INFLIGHT
013642,000160: 23,2000 BANK
013643,000161:
013644,000162: 23,2041 COUNT* $$/GEOM
013645,000163:
013646,000164: 23,2041 47135 RRNB SLOAD RTB
013647,000165: 23,2042 03753 TANGNB
013648,000166: 23,2043 21577 CDULOGIC
013649,000167: 23,2044 41401 SETPD PUSH # TRUNNION ANGLE TO 0
013650,000168: 23,2045 00001 0
013651,000169: 23,2046 57556 SIN DCOMP
013652,000170: 23,2047 14043 STODL 34D # Y COMPONENT
013653,000171:
013654,000172: 23,2050 41546 COS PUSH # .5 COS(T) TO 0
013655,000173: 23,2051 47135 SLOAD RTB
013656,000174: 23,2052 03754 TANGNB +1
013657,000175: 23,2053 21577 CDULOGIC
013658,000176: 23,2054 71406 RRNB1 PUSH COS # SHAFT ANGLE TO 2
013659,000177: 23,2055 72405 DMP SL1
013660,000178: 23,2056 00001 0
013661,000179: 23,2057 14045 STODL 36D # Z COMPONENT
013662,000180:
013663,000181: 23,2060 41356 SIN DMP
013664,000182: 23,2061 77752 SL1
013665,000183: 23,2062 24041 STOVL 32D
013666,000184: 23,2063 00041 32D
013667,000185: 23,2064 77616 RVQ
013668,000186:
013669,000187: # THIS ENTRY TO RRNB REQUIRES THE TRUNNION AND SHAFT ANGLES IN MPAC AND MPAC +1 RESPECTIVELY
013670,000188:
013671,000189: 23,2065 14025 RRNBMPAC STODL 20D # SAVE SHAFT CDU IN 21.
013672,000190: 23,2066 00155 MPAC # SET MODE TO DP. (THE PRECEEDING STORE
013673,000191: # MAY BE DP, TP OR VECTOR.)
013674,000192: 23,2067 40234 RTB SETPD
013675,000193: 23,2070 21577 CDULOGIC
013676,000194: 23,2071 00001 0
013677,000195: 23,2072 73406 PUSH SIN # TRUNNION ANGLE TO 0
013678,000196: 23,2073 77676 DCOMP
013679,000197: 23,2074 14043 STODL 34D # Y COMPONENT
013680,000198: 23,2075 41546 COS PUSH # .5COS(T) TO 0
013681,000199: 23,2076 47135 SLOAD RTB # PICK UP CDU'S.
013682,000200: 23,2077 00026 21D
013683,000201: 23,2100 21577 CDULOGIC
013684,000202: 23,2101 77650 GOTO
013685,000203: 23,2102 46054 RRNB1
|
|
Page 327
This page has nothing on it.
|
013688,000206:
013689,000207:
End of include-file LEM_GEOMETRY.agc. Parent file is MAIN.agc