Source Code
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These source-code files derive from a printout of Luminary 116 (the Apollo 12
Lunar Module guidance computer program), from the personal library of
original AGC developer Don Eyles, digitally photographed at archive.org,
financially sponsored by Ron Burkey, and transcribed to source code by a
team of volunteers. This colorized, syntax-highlighted form was created
by assembling that transcribed source code. Note that the full page images
are available on the
Virtual AGC project page at archive.org, while reduced-size images
are presented at the VirtualAGC project website. Report or fix any
transcription errors at
the Virtual AGC project code repository. Notations on the program listing read, in part: GAP: ASSEMBLE REVISION 116 OF AGC PROGRAM LUMINARY BY NASA 2021112-071 19:09 AUG. 11,1969Note that the date is the date of the printout, not the date of the program revision. |
035803,000002: ## Copyright: Public domain.
035804,000003: ## Filename: P12.agc
035805,000004: ## Purpose: A section of Luminary revision 116.
035806,000005: ## It is part of the source code for the Lunar Module's (LM)
035807,000006: ## Apollo Guidance Computer (AGC) for Apollo 12.
035808,000007: ## This file is intended to be a faithful transcription, except
035809,000008: ## that the code format has been changed to conform to the
035810,000009: ## requirements of the yaYUL assembler rather than the
035811,000010: ## original YUL assembler.
035812,000011: ## Reference: pp. 831-835
035813,000012: ## Assembler: yaYUL
035814,000013: ## Contact: Ron Burkey <info@sandroid.org>.
035815,000014: ## Website: www.ibiblio.org/apollo/index.html
035816,000015: ## Mod history: 2017-01-22 MAS Created from Luminary 99.
035817,000016: ## 2017-01-28 RSB Proofed comment text using octopus/prooferComments
035818,000017: ## and fixed errors found.
035819,000018: ## 2017-03-09 HG Transcribed
035820,000019: ## 2017-03-13 RSB Proofed comment text via 3-way diff vs
035821,000020: ## Luminary 99 and 131.
035822,000021: ## 2017-08-26 MAS Fixed a comment-text error found while transcribing
035823,000022: ## Zerlina 56.
035824,000023:
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Page 831 |
035826,000025: 24,3677 BANK 24
035827,000026: 30,2000 SETLOC P12
035828,000027: 30,2000 BANK
035829,000028:
035830,000029: 30,2061 E7,1515 EBANK= DVCNTR
035831,000030: 30,2061 COUNT* $$/P12
035832,000031:
035833,000032: 30,2061 05353 P12LM TC PHASCHNG
035834,000033: 30,2062 04024 OCT 04024
035835,000034:
035836,000035: 30,2063 04616 TC BANKCALL
035837,000036: 30,2064 11236 CADR R02BOTH # CHECK THE STATUS OF THE IMU.
035838,000037:
035839,000038: 30,2065 06011 TC CLRADMOD # INITIALIZE RADMODES FOR R29.
035840,000039:
035841,000040: 30,2066 36000 CAF THRESH2 # INITIALIZE DVMON
035842,000041: 30,2067 55250 TS DVTHRUSH
035843,000042: 30,2070 34751 CAF FOUR
035844,000043: 30,2071 55515 TS DVCNTR
035845,000044:
035846,000045: 30,2072 34755 CA ZERO
035847,000046: 30,2073 55462 TS TRKMKCNT # SHOW THAT R29 DOWNLINK DATA IS NOT READY
035848,000047:
035849,000048: 30,2074 33022 CAF V06N33A
035850,000049: 30,2075 04616 TC BANKCALL # FLASH TIG
035851,000050: 30,2076 20477 CADR GOFLASH
035852,000051: 30,2077 16001 TCF GOTOPOOH
035853,000052: 30,2100 12102 TCF +2 # PROCEED
035854,000053: 30,2101 12074 TCF -5 # ENTER
035855,000054:
035856,000055: 30,2102 05353 TC PHASCHNG
035857,000056: 30,2103 04024 OCT 04024
035858,000057:
035859,000058: 30,2104 06042 TC INTPRET
035860,000059: 30,2105 43014 SET SET
035861,000060: 30,2106 03067 MUNFLAG
035862,000061: 30,2107 06464 ACC4-2FL
035863,000062: 30,2110 43014 SET CLEAR
035864,000063: 30,2111 00075 R10FLAG
035865,000064: 30,2112 00270 RNDVZFLG
035866,000065: 30,2113 43014 SET SET
035867,000066: 30,2114 04464 FLPI
035868,000067: 30,2115 04461 FLVR
035869,000068: 30,2116 77624 CALL # INITIALIZE WM AND /LAND/
035870,000069: 30,2117 71343 GUIDINIT
035871,000070: 30,2120 77624 CALL
035872,000071: 30,2121 60251 P12INIT
035873,000072: 30,2122 77745 P12LMB DLOAD
035874,000073: 30,2123 25753 (TGO)A # SET TGO TO AN INITIAL NOMINAL VALUE.
035875,000074: 30,2124 17517 STODL TGO
035876,000075:
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Page 832 |
035878,000077: 30,2125 03442 TIG
035879,000078: 30,2126 34041 STCALL TDEC1
035880,000079: 30,2127 27060 LEMPREC # ROTATE THE STATE VECTORS TO THE
035881,000080: 30,2130 64375 VLOAD MXV # IGNITION TIME.
035882,000081: 30,2131 00007 VATT
035883,000082: 30,2132 01734 REFSMMAT
035884,000083: 30,2133 77772 VSL1
035885,000084: 30,2134 27601 STOVL V1S # COMPUTE V1S = VEL(TIG)*2(-7) M/CS.
035886,000085: 30,2135 00001 RATT
035887,000086: 30,2136 52521 MXV VSL6
035888,000087: 30,2137 01734 REFSMMAT
035889,000088: 30,2140 37521 STCALL R # COMPUTE R = POS(TIG)*2(-24)M.
035890,000089: 30,2141 67067 MUNGRAV # COMPUTE GDT1/2(TIG)*2(-7)M/CS.
035891,000090: 30,2142 53575 VLOAD UNIT
035892,000091: 30,2143 03521 R
035893,000092: 30,2144 37537 STCALL UNIT/R/ # COMPUTE UNIT/R/ FOR YCOMP.
035894,000093: 30,2145 57312 YCOMP
035895,000094: 30,2146 57461 SR DCOMP
035896,000095: 30,2147 20606 5D
035897,000096: 30,2150 17643 STODL XRANGE # INITIALIZE XRANGE FOR NOUN 76.
035898,000097: 30,2151 31367 VINJNOM
035899,000098: 30,2152 16277 STODL ZDOTD
035900,000099: 30,2153 31371 RDOTDNOM
035901,000100: 30,2154 02273 STORE RDOTD
035902,000101: 30,2155 77776 EXIT
035903,000102:
035904,000103: 30,2156 05353 TC PHASCHNG
035905,000104: 30,2157 04024 OCT 04024
035906,000105:
035907,000106: 30,2160 33021 NEWLOAD CAF V06N76 # FLASH CROSS-RANGE AND APOLUNE VALUES.
035908,000107: 30,2161 04616 TC BANKCALL
035909,000108: 30,2162 20477 CADR GOFLASH
035910,000109: 30,2163 16001 TCF GOTOPOOH
035911,000110: 30,2164 12166 TCF +2 # PROCEED
035912,000111: 30,2165 12160 TCF NEWLOAD # ENTER NEW DATA.
035913,000112:
035914,000113: 30,2166 32314 CAF P12ADRES
035915,000114: 30,2167 55455 TS WHICH
035916,000115:
035917,000116: 30,2170 05353 TC PHASCHNG
035918,000117: 30,2171 04024 OCT 04024
035919,000118:
035920,000119: 30,2172 06042 TC INTPRET
035921,000120: 30,2173 54345 DLOAD SL
035922,000121: 30,2174 03643 XRANGE
035923,000122: 30,2175 20206 5D
035924,000123: 30,2176 77615 DAD
035925,000124: 30,2177 02335 Y
035926,000125: 30,2200 27633 STOVL YCO
035927,000126: 30,2201 03537 UNIT/R/
035928,000127:
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Page 833 |
035930,000129: 30,2202 53361 VXSC VAD
035931,000130: 30,2203 31365 49FPS
035932,000131: 30,2204 03601 V1S
035933,000132: 30,2205 03527 STORE V # V(TIPOVER) = V(IGN) + 57FPS (UNIT/R/)
035934,000133: 30,2206 72441 DOT SL1
035935,000134: 30,2207 03537 UNIT/R/
035936,000135: 30,2210 27474 STOVL RDOT # RDOT * 2(-7)
035937,000136: 30,2211 03537 UNIT/R/
035938,000137: 30,2212 53435 VXV UNIT
035939,000138: 30,2213 03720 QAXIS
035940,000139: 30,2214 37726 STCALL ZAXIS1
035941,000140: 30,2215 60315 ASCENT
035942,000141: 30,2216 77745 P12RET DLOAD
035943,000142: 30,2217 02361 ATP # ATP(2)*2(18)
035944,000143: 30,2220 65316 DSQ PDDL
035945,000144: 30,2221 02355 ATY # ATY(2)*2(18)
035946,000145: 30,2222 43316 DSQ DAD
035947,000146: 30,2223 75454 BZE SQRT
035948,000147: 30,2224 60230 YAWDUN
035949,000148: 30,2225 55352 SL1 BDDV
035950,000149: 30,2226 02355 ATY
035951,000150: 30,2227 77736 ARCSIN
035952,000151: 30,2230 26363 YAWDUN STOVL YAW
035953,000152: 30,2231 03254 UNFC/2
035954,000153: 30,2232 50256 UNIT DOT
035955,000154: 30,2233 03537 UNIT/R/
035956,000155: 30,2234 65552 SL1 ARCCOS
035957,000156: 30,2235 77676 DCOMP
035958,000157: 30,2236 02365 STORE PITCH
035959,000158: 30,2237 77776 EXIT
035960,000159: 30,2240 05353 TC PHASCHNG
035961,000160: 30,2241 04024 OCT 04024
035962,000161:
035963,000162: 30,2242 00004 INHINT
035964,000163: 30,2243 04674 TC IBNKCALL
035965,000164: 30,2244 40143 CADR PFLITEDB
035966,000165: 30,2245 05516 TC DOWNFLAG
035967,000166: 30,2246 00213 ADRES FLPI
035968,000167:
035969,000168: 30,2247 04635 TC POSTJUMP
035970,000169: 30,2250 74130 CADR BURNBABY
035971,000170:
035972,000171: 30,2251 77745 P12INIT DLOAD # INITIALIZE ENGINE DATA. USED FOR P12 AND
035973,000172: 30,2252 16013 (1/DV)A # P71.
035974,000173: 30,2253 03641 STORE 1/DV3
035975,000174: 30,2254 03637 STORE 1/DV2
035976,000175: 30,2255 17635 STODL 1/DV1
035977,000176: 30,2256 16017 (AT)A
035978,000177: 30,2257 16263 STODL AT
035979,000178: 30,2260 16021 (TBUP)A
035980,000179:
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Page 834 |
035982,000181: 30,2261 16271 STODL TBUP
035983,000182: 30,2262 34013 ATDECAY
035984,000183: 30,2263 54276 DCOMP SL
035985,000184: 30,2264 20214 11D
035986,000185: 30,2265 02267 STORE TTO
035987,000186: 30,2266 57535 SLOAD DCOMP
035988,000187: 30,2267 26001 APSVEX
035989,000188: 30,2270 77702 SR2
035990,000189: 30,2271 02265 STORE VE
035991,000190: 30,2272 43414 BOFF RVQ
035992,000191: 30,2273 04747 FLAP
035993,000192: 30,2274 60275 COMMINIT
035994,000193: 30,2275 43345 COMMINIT DLOAD DAD # INITIALIZE TARGET DATA. USED BY P12, P70
035995,000194: 30,2276 25751 HINJECT # AND P71 IF IT DOES NOT FOLLOW P70.
035996,000195: 30,2277 02333 /LAND/
035997,000196: 30,2300 17631 STODL RCO
035998,000197: 30,2301 06524 HI6ZEROS
035999,000198: 30,2302 03654 STORE TXO
036000,000199: 30,2303 03633 STORE YCO
036001,000200: 30,2304 26275 STOVL YDOTD
036002,000201: 30,2305 01563 VRECTCSM
036003,000202: 30,2306 64235 VXV MXV
036004,000203: 30,2307 01555 RRECTCSM
036005,000204: 30,2310 01734 REFSMMAT
036006,000205: 30,2311 77656 UNIT
036007,000206: 30,2312 03720 STORE QAXIS
036008,000207: 30,2313 77616 RVQ
036009,000208:
036010,000209: 30,2314 02024 P12ADRES REMADR P12TABLE
036011,000210:
036012,000211: 34,2000 SETLOC ASENT8
036013,000212: 34,2000 BANK
036014,000213: 34,3343 COUNT* $$/P12
036015,000214:
036016,000215: 34,3343 40220 GUIDINIT STQ SETPD
036017,000216: 34,3344 01163 TEMPR60
036018,000217: 34,3345 00001 0D
036019,000218: 34,3346 41575 VLOAD PUSH
036020,000219: 34,3347 06516 UNITZ
036021,000220: 34,3350 41434 RTB PUSH
036022,000221: 34,3351 21574 LOADTIME
036023,000222: 34,3352 77624 CALL
036024,000223: 34,3353 55716 RP-TO-R
036025,000224: 34,3354 74321 MXV VXSC
036026,000225: 34,3355 01734 REFSMMAT
036027,000226: 34,3356 16027 MOONRATE
036028,000227: 34,3357 26325 STOVL WM
036029,000228: 34,3360 02023 RLS
036030,000229: 34,3361 52446 ABVAL SL3
036031,000230: 34,3362 36333 STCALL /LAND/
036032,000231:
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Page 835 |
036034,000233: 34,3363 01163 TEMPR60
036035,000234:
036036,000235: 34,3364 00046 07374 49FPS 2DEC .149352 B-6 # EXPECTED RDOT AT TIPOVER
036037,000236: 34,3366 04145 15527 VINJNOM 2DEC 16.7924 B-7 # 5509.5 FPS(APO=30NM WITH RDOT=19.5FPS)
036038,000237: 34,3370 00007 23346 RDOTDNOM 2DEC .059436 B-7 # 19.5 FPS
036039,000238:
036040,000239:
End of include-file P12.agc. Parent file is MAIN.agc