Source Code
027857,000001: # Copyright: Public domain.
027858,000002: # Filename: LAMBERT_AIMPOINT_GUIDANCE.agc
027859,000003: # Purpose: Part of the source code for Luminary 1A build 099.
027860,000004: # It is part of the source code for the Lunar Module's (LM)
027861,000005: # Apollo Guidance Computer (AGC), for Apollo 11.
027862,000006: # Assembler: yaYUL
027863,000007: # Contact: Ron Burkey <info@sandroid.org>.
027864,000008: # Website: www.ibiblio.org/apollo.
027865,000009: # Pages: 651-653
027866,000010: # Mod history: 2009-05-18 RSB Transcribed from Luminary 099
027867,000011: # page images.
027868,000012: # 2009-06-05 RSB Corrected 4 typos.
027869,000013: # 2009-06-07 RSB Fixed a typo.
027870,000014:
027871,000015: # This source code has been transcribed or otherwise adapted from
027872,000016: # digitized images of a hardcopy from the MIT Museum. The digitization
027873,000017: # was performed by Paul Fjeld, and arranged for by Deborah Douglas of
027874,000018: # the Museum. Many thanks to both. The images (with suitable reduction
027875,000019: # in storage size and consequent reduction in image quality as well) are
027876,000020: # available online at www.ibiblio.org/apollo. If for some reason you
027877,000021: # find that the images are illegible, contact me at info@sandroid.org
027878,000022: # about getting access to the (much) higher-quality images which Paul
027879,000023: # actually created.
027880,000024:
027881,000025: # Notations on the hardcopy document read, in part:
027882,000026:
027883,000027: # Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
027884,000028: # 16:27 JULY 14, 1969
027885,000029:
027886,000030: # Page 651
027887,000031:
027888,000032: # GENERAL LAMBERT AIMPOINT GUIDANCE **
027889,000033: # WRITTEN BY RAMA M AIYAWAR
027890,000034:
027891,000035: # PROGRAM P-31 DESCRIPTION **
027892,000036:
027893,000037: # 1. TO ACCEPT TARGETING PARAMETERS OBTAINED FROM A SOURCE EXTERNAL
027894,000038: # TO THE LEM AND COMPUTE THERE FROM THE REQUIRED-VELOCITY AND
027895,000039: # OTHER INITIAL CONDITIONS REQUIRED BY LM FOR DESIRED MANEUVER.
027896,000040: # THE TARGETING PARAMETERS ARE TIG (TIME OF IGNITION), TARGET
027897,000041: # VECTOR (RTARG), AND THE TIME FROM TIG UNTIL THE TARGET IS
027898,000042: # REACHED (DELLT4), DESIRED TIME OF FLIGHT FROM RINIT TO RTARG.
027899,000043:
027900,000044: # ASSUMPTIONS **
027901,000045:
027902,000046: # 1. THE TARGET PARAMETERS MAY HAVE BEEN LOADED PRIOR TO THE
027903,000047: # EXECUTION OF THIS PROGRAM.
027904,000048: # 2. THIS PROGRAM IS APPLICABLE IN EITHER EARTH OR LUNAR ORBIT.
027905,000049: # 3. THIS PROGRAM IS DESIGNED FOR ONE-MAN OPERATION, AND SHOULD
027906,000050: # BE SELECTED BY THE ASTRONAUT BY DSKY ENTRY V37 E31.
027907,000051:
027908,000052: # SUBROUTINES USED **
027909,000053: #
027910,000054: # MANUPARM, TTG/N35, R02BOTH, MIDGIM, DISPMGA, FLAGDOWN, BANKCALL,
027911,000055: # GOTOPOOH, ENDOFJOB, PHASCHNG, GOFLASHR, GOFLASH.
027912,000056:
027913,000057: # MANUPARM CALCULATES APOGEE, PERIGEE ALTITUDES AND DELTAV DESIRED
027914,000058: # FOR THE MANEUVER.
027915,000059:
027916,000060: # TTG/N35 CLOCKTASK - UPDATES CLOCK.
027917,000061:
027918,000062: # MIDGIM CALCULATES MIDDLE GIMBAL ANGLE FOR DISPLAY.
027919,000063:
027920,000064: # R02BOTH IMU - STATUS CHECK ROUTINE.
027921,000065:
027922,000066: # DISPLAYS USED IN P-31LM **
027923,000067:
027924,000068: # V06N33 DISPLAY SOTRED TIG (IN HRS. MINS. SECS.)
027925,000069: # V06N42 DISPLAY APOGEE, PERIGEE, DELTAV.
027926,000070: # V16N35 DISPLAY TIME FROM TIG.
027927,000071: # V06N45 TIME FROM IGNITION AND MIDDLE GIMBAL ANGLE.
027928,000072:
027929,000073: # ERASABLE INITIALIZATION REQUIRED **
027930,000074:
027931,000075: # TIG TIME OF IGNITION DP (B+28) CS.
027932,000076:
027933,000077: # DELLT4 DESIRED TIME OF FLIGHT DP (B+28) CS
027934,000078: # FROM RINIT TO RTARG.
027935,000079:
027936,000080: # RTARG RADIUS VECTOR OF TARGET POSITION VECTOR
027937,000081: # RADIUS VECTOR SCALED TO (B+29)METERS IF EARTH ORBIT
027938,000082: # Page 652
027939,000083: # RADIUS VECTOR SCALED TO (B+27)METERS IF MOON ORBIT
027940,000084:
027941,000085: # OUTPUT **
027942,000086:
027943,000087: # HAPO APOGEE ALTITUDE
027944,000088: # HPER PERIGEE ALTITUDE
027945,000089: # VGDISP MAG. OF DELTAV FOR DISPLAY, SCALING B+7 M/CS EARTH
027946,000090: # MAG. OF DELTAV FOR DISPLAY, SCALING B+5 M/CS MOON
027947,000091: # MIDGIM MIDDLE GIMBAL ANGLE
027948,000092: # XDELVFLG RESETS XDELVFLG FOR LAMBERT VG COMPUTATIONS
027949,000093:
027950,000094: # ALARMS OR ABORTS NONE **
027951,000095:
027952,000096: # RESTARTS ARE VIA GROUP 4 **
027953,000097:
027954,000098: 35,2000 SETLOC GLM
027955,000099: 35,2000 BANK
027956,000100:
027957,000101: 35,2450 E7,1470 EBANK= SUBEXIT
027958,000102:
027959,000103: 35,2450 COUNT* $$/P31
027960,000104: 35,2450 02361 P31 TC P20FLGON
027961,000105: 35,2451 32025 CAF V06N33 # T16
027962,000106: 35,2452 03712 TC VNP00H
027963,000107: 35,2453 06037 TC INTPRET
027964,000108: 35,2454 71214 CLEAR DLOAD
027965,000109: 35,2455 00670 UPDATFLG
027966,000110: 35,2456 03442 TIG
027967,000111: 35,2457 34041 STCALL TDEC1 # INTEGRATE STATE VECTORS TO TIG
027968,000112: 35,2460 27057 LEMPREC
027969,000113: 35,2461 40375 VLOAD SETPD
027970,000114: 35,2462 00001 RATT
027971,000115: 35,2463 00001 0D
027972,000116: 35,2464 03642 STORE RTIG
027973,000117: 35,2465 26323 STOVL RINIT
027974,000118: 35,2466 00007 VATT
027975,000119: 35,2467 03650 STORE VTIG
027976,000120: 35,2470 16331 STODL VINIT
027977,000121: 35,2471 32420 P30ZERO
027978,000122: 35,2472 65206 PUSH PDDL # E4 AND NUMIT = 0
027979,000123: 35,2473 03452 DELLT4
027980,000124: 35,2474 66015 DAD SXA,1
027981,000125: 35,2475 03442 TIG
027982,000126: 35,2476 02776 RTX1
027983,000127: 35,2477 03631 STORE TPASS4
027984,000128: 35,2500 45134 SXA,2 CALL
027985,000129: 35,2501 02777 RTX2
027986,000130: 35,2502 22000 INITVEL
027987,000131: 35,2503 41575 VLOAD PUSH
027988,000132: # Page 653
027989,000133: 35,2504 02366 DELVEET3
027990,000134: 35,2505 03656 STORE DELVSIN
027991,000135: 35,2506 43046 ABVAL CLEAR
027992,000136: 35,2507 01267 XDELVFLG
027993,000137: 35,2510 37664 STCALL VGDISP
027994,000138: 35,2511 15733 GET.LVC
027995,000139: 35,2512 63375 VLOAD PDVL
027996,000140: 35,2513 03642 RTIG
027997,000141: 35,2514 02337 VIPRIME
027998,000142: 35,2515 77624 CALL
027999,000143: 35,2516 46316 PERIAPO1
028000,000144: 35,2517 77624 CALL
028001,000145: 35,2520 46426 SHIFTR1
028002,000146: 35,2521 77624 CALL # LIMIT DISPLAY TO 9999.9 N. MI.
028003,000147: 35,2522 45636 MAXCHK
028004,000148: 35,2523 16321 STODL HPER
028005,000149: 35,2524 00005 4D
028006,000150: 35,2525 77624 CALL
028007,000151: 35,2526 46426 SHIFTR1
028008,000152: 35,2527 77624 CALL # LIMIT DISPLAY TO 9999.9 N. MI.
028009,000153: 35,2530 45636 MAXCHK
028010,000154: 35,2531 02317 STORE HAPO
028011,000155: 35,2532 77776 EXIT
028012,000156: 35,2533 33727 CAF V06N81 # DELVLVC
028013,000157: 35,2534 03712 TC VNP00H
028014,000158: 35,2535 32026 CAF V06N42 # HAPO, HPER, VGDISP
028015,000159: 35,2536 03712 TC VNP00H
028016,000160: 35,2537 06037 TC INTPRET
028017,000161: 35,2540 45014 REVN1645 SET CALL # TRKMKCNT, TTOGO, +MGA
028018,000162: 35,2541 01071 FINALFLG
028019,000163: 35,2542 73606 VN1645
028020,000164: 35,2543 77650 GOTO
028021,000165: 35,2544 72540 REVN1645
028022,000166:
028023,000167:
028024,000168: # *** END OF LEMP30S .103 ***
028025,000169:
End of include-file LAMBERT_AIMPOINT_GUIDANCE.agc. Parent file is MAIN.agc