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 Luminary 131 (Apollo 13)
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 001 OF AGC PROGRAM LMY99 BY NASA 2021112-061 20'35 OCT. 28,1968Note that the date is the date of the printout, not the date of the program revision. |
028000,000002: ## Copyright: Public domain.
028001,000003: ## Filename: LAMBERT_AIMPOINT_GUIDANCE.agc
028002,000004: ## Purpose: Part of the source code for Luminary 1A build 099.
028003,000005: ## It is part of the source code for the Lunar Module's (LM)
028004,000006: ## Apollo Guidance Computer (AGC), for Apollo 11.
028005,000007: ## Assembler: yaYUL
028006,000008: ## Contact: Ron Burkey <info@sandroid.org>.
028007,000009: ## Website: www.ibiblio.org/apollo.
028008,000010: ## Pages: 651-653
028009,000011: ## Mod history: 2009-05-18 RSB Transcribed from Luminary 099
028010,000012: ## page images.
028011,000013: ## 2009-06-05 RSB Corrected 4 typos.
028012,000014: ## 2009-06-07 RSB Fixed a typo.
028013,000015: ## 2016-12-14 RSB VNP00H -> VNPOOH.
028014,000016: ## 2016-12-14 RSB Proofed text comments with octopus/ProoferComments
028015,000017: ## and corrected the errors found.
028016,000018: ##
028017,000019: ## This source code has been transcribed or otherwise adapted from
028018,000020: ## digitized images of a hardcopy from the MIT Museum. The digitization
028019,000021: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
028020,000022: ## the Museum. Many thanks to both. The images (with suitable reduction
028021,000023: ## in storage size and consequent reduction in image quality as well) are
028022,000024: ## available online at www.ibiblio.org/apollo. If for some reason you
028023,000025: ## find that the images are illegible, contact me at info@sandroid.org
028024,000026: ## about getting access to the (much) higher-quality images which Paul
028025,000027: ## actually created.
028026,000028: ##
028027,000029: ## Notations on the hardcopy document read, in part:
028028,000030: ##
028029,000031: ## Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
028030,000032: ## 16:27 JULY 14, 1969
028031,000033:
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Page 651 |
028033,000035:
028034,000036: # GENERAL LAMBERT AIMPOINT GUIDANCE **
028035,000037: # WRITTEN BY RAMA M AIYAWAR
028036,000038:
028037,000039: # PROGRAM P-31 DESCRIPTION **
028038,000040:
028039,000041: # 1. TO ACCEPT TARGETING PARAMETERS OBTAINED FROM A SOURCE EXTERNAL
028040,000042: # TO THE LEM AND COMPUTE THERE FROM THE REQUIRED-VELOCITY AND
028041,000043: # OTHER INITIAL CONDITIONS REQUIRED BY LM FOR DESIRED MANEUVER.
028042,000044: # THE TARGETING PARAMETERS ARE TIG (TIME OF IGNITION), TARGET
028043,000045: # VECTOR (RTARG), AND THE TIME FROM TIG UNTIL THE TARGET IS
028044,000046: # REACHED (DELLT4), DESIRED TIME OF FLIGHT FROM RINIT TO RTARG..
028045,000047:
028046,000048: # ASSUMPTIONS **
028047,000049:
028048,000050: # 1. THE TARGET PARAMETERS MAY HAVE BEEN LOADED PRIOR TO THE
028049,000051: # EXECUTION OF THIS PROGRAM.
028050,000052: # 2. THIS PROGRAM IS APPLICABLE IN EITHER EARTH OR LUNAR ORBIT.
028051,000053: # 3. THIS PROGRAM IS DESIGNED FOR ONE-MAN OPERATION, AND SHOULD
028052,000054: # BE SELECTED BY THE ASTRONAUT BY DSKY ENTRY V37 E31.
028053,000055:
028054,000056: # SUBROUTINES USED **
028055,000057: #
028056,000058: # MANUPARM, TTG/N35, R02BOTH, MIDGIM, DISPMGA, FLAGDOWN, BANKCALL,
028057,000059: # GOTOPOOH, ENDOFJOB, PHASCHNG, GOFLASHR, GOFLASH.
028058,000060:
028059,000061: # MANUPARM CALCULATES APOGEE, PERIGEE ALTITUDES AND DELTAV DESIRED
028060,000062: # FOR THE MANEUVER.
028061,000063:
028062,000064: # TTG/N35 CLOCKTASK - UPDATES CLOCK.
028063,000065:
028064,000066: # MIDGIM CALCULATES MIDDLE GIMBAL ANGLE FOR DISPLAY.
028065,000067:
028066,000068: # R02BOTH IMU - STATUS CHECK ROUTINE.
028067,000069:
028068,000070: # DISPLAYS USED IN P-31LM **
028069,000071:
028070,000072: # V06N33 DISPLAY SOTRED TIG (IN HRS. MINS. SECS)
028071,000073: # V06N42 DISPLAY APOGEE, PERIGEE, DELTAV.
028072,000074: # V16N35 DISPLAY TIME FROM TIG.
028073,000075: # V06N45 TIME FROM IGNITION AND MIDDLE GIMBAL ANGLE.
028074,000076:
028075,000077: # ERASABLE INITIALIZATION REQUIRED **
028076,000078:
028077,000079: # TIG TIME OF IGNITION DP (B+28) CS.
028078,000080:
028079,000081: # DELLT4 DESIRED TIME OF FLIGHT DP (B+28) CS
028080,000082: # FROM RINIT TO RTARG.
028081,000083:
028082,000084: # RTARG RADIUS VECTOR OF TARGET POSITION VECTOR
028083,000085: # RADIUS VECTOR SCALED TO (B+29)METERS IF EARTH ORBIT
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Page 652 |
028085,000087: # RADIUS VECTOR SCALED TO (B+27)METERS IF MOON ORBIT
028086,000088:
028087,000089: # OUTPUT **
028088,000090:
028089,000091: # HAPO APOGEE ALTITUDE
028090,000092: # HPER PERIGEE ALTITUDE
028091,000093: # VGDISP MAG. OF DELTAV FOR DISPLAY, SCALING B+7 M/CS EARTH
028092,000094: # MAG. OF DELTAV FOR DISPLAY, SCALING B+5 M/CS MOON
028093,000095: # MIDGIM MIDDLE GIMBAL ANGLE
028094,000096: # XDELVFLG RESETS XDELVFLG FOR LAMBERT VG COMPUTATIONS
028095,000097:
028096,000098: # ALARMS OR ABORTS NONE **
028097,000099:
028098,000100: # RESTARTS ARE VIA GROUP 4 **
028099,000101:
028100,000102: 35,2000 SETLOC GLM
028101,000103: 35,2000 BANK
028102,000104:
028103,000105: 35,2450 E7,1470 EBANK= SUBEXIT
028104,000106:
028105,000107: 35,2450 COUNT* $$/P31
028106,000108: 35,2450 02361 P31 TC P20FLGON
028107,000109: 35,2451 32025 CAF V06N33 # TIG
028108,000110: 35,2452 03712 TC VNPOOH
028109,000111: 35,2453 06037 TC INTPRET
028110,000112: 35,2454 71214 CLEAR DLOAD
028111,000113: 35,2455 00670 UPDATFLG
028112,000114: 35,2456 03442 TIG
028113,000115: 35,2457 34041 STCALL TDEC1 # INTEGRATE STATE VECTORS TO TIG
028114,000116: 35,2460 27057 LEMPREC
028115,000117: 35,2461 40375 VLOAD SETPD
028116,000118: 35,2462 00001 RATT
028117,000119: 35,2463 00001 0D
028118,000120: 35,2464 03642 STORE RTIG
028119,000121: 35,2465 26323 STOVL RINIT
028120,000122: 35,2466 00007 VATT
028121,000123: 35,2467 03650 STORE VTIG
028122,000124: 35,2470 16331 STODL VINIT
028123,000125: 35,2471 32420 P30ZERO
028124,000126: 35,2472 65206 PUSH PDDL # E4 AND NUMIT = 0
028125,000127: 35,2473 03452 DELLT4
028126,000128: 35,2474 66015 DAD SXA,1
028127,000129: 35,2475 03442 TIG
028128,000130: 35,2476 02776 RTX1
028129,000131: 35,2477 03631 STORE TPASS4
028130,000132: 35,2500 45134 SXA,2 CALL
028131,000133: 35,2501 02777 RTX2
028132,000134: 35,2502 22000 INITVEL
028133,000135: 35,2503 41575 VLOAD PUSH
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Page 653 |
028135,000137: 35,2504 02366 DELVEET3
028136,000138: 35,2505 03656 STORE DELVSIN
028137,000139: 35,2506 43046 ABVAL CLEAR
028138,000140: 35,2507 01267 XDELVFLG
028139,000141: 35,2510 37664 STCALL VGDISP
028140,000142: 35,2511 15733 GET.LVC
028141,000143: 35,2512 63375 VLOAD PDVL
028142,000144: 35,2513 03642 RTIG
028143,000145: 35,2514 02337 VIPRIME
028144,000146: 35,2515 77624 CALL
028145,000147: 35,2516 46316 PERIAPO1
028146,000148: 35,2517 77624 CALL
028147,000149: 35,2520 46426 SHIFTR1
028148,000150: 35,2521 77624 CALL # LIMIT DISPLAY TO 9999.9 N. MI.
028149,000151: 35,2522 45636 MAXCHK
028150,000152: 35,2523 16321 STODL HPER
028151,000153: 35,2524 00005 4D
028152,000154: 35,2525 77624 CALL
028153,000155: 35,2526 46426 SHIFTR1
028154,000156: 35,2527 77624 CALL # LIMIT DISPLAY TO 9999.9 N. MI.
028155,000157: 35,2530 45636 MAXCHK
028156,000158: 35,2531 02317 STORE HAPO
028157,000159: 35,2532 77776 EXIT
028158,000160: 35,2533 33727 CAF V06N81 # DELVLVC
028159,000161: 35,2534 03712 TC VNPOOH
028160,000162: 35,2535 32026 CAF V06N42 # HAPO, HPER, VGDISP
028161,000163: 35,2536 03712 TC VNPOOH
028162,000164: 35,2537 06037 TC INTPRET
028163,000165: 35,2540 45014 REVN1645 SET CALL # TRKMKCNT, TTOGO, +MGA
028164,000166: 35,2541 01071 FINALFLG
028165,000167: 35,2542 73606 VN1645
028166,000168: 35,2543 77650 GOTO
028167,000169: 35,2544 72540 REVN1645
028168,000170:
End of include-file LAMBERT_AIMPOINT_GUIDANCE.agc. Parent file is MAIN.agc