Source Code
027839,000001: # Copyright: Public domain.
027840,000002: # Filename: LAMBERT_AIMPOINT_GUIDANCE.agc
027841,000003: # Purpose: Part of the source code for Luminary 1A build 099.
027842,000004: # It is part of the source code for the Lunar Module's (LM)
027843,000005: # Apollo Guidance Computer (AGC), for Apollo 11.
027844,000006: # Assembler: yaYUL
027845,000007: # Contact: Ron Burkey <info@sandroid.org>.
027846,000008: # Website: www.ibiblio.org/apollo.
027847,000009: # Pages: 651-653
027848,000010: # Mod history: 2009-05-18 RSB Transcribed from Luminary 099
027849,000011: # page images.
027850,000012: # 2009-06-05 RSB Corrected 4 typos.
027851,000013: # 2009-06-07 RSB Fixed a typo.
027852,000014:
027853,000015: # This source code has been transcribed or otherwise adapted from
027854,000016: # digitized images of a hardcopy from the MIT Museum. The digitization
027855,000017: # was performed by Paul Fjeld, and arranged for by Deborah Douglas of
027856,000018: # the Museum. Many thanks to both. The images (with suitable reduction
027857,000019: # in storage size and consequent reduction in image quality as well) are
027858,000020: # available online at www.ibiblio.org/apollo. If for some reason you
027859,000021: # find that the images are illegible, contact me at info@sandroid.org
027860,000022: # about getting access to the (much) higher-quality images which Paul
027861,000023: # actually created.
027862,000024:
027863,000025: # Notations on the hardcopy document read, in part:
027864,000026:
027865,000027: # Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
027866,000028: # 16:27 JULY 14, 1969
027867,000029:
027868,000030: # Page 651
027869,000031:
027870,000032: # GENERAL LAMBERT AIMPOINT GUIDANCE **
027871,000033: # WRITTEN BY RAMA M AIYAWAR
027872,000034:
027873,000035: # PROGRAM P-31 DESCRIPTION **
027874,000036:
027875,000037: # 1. TO ACCEPT TARGETING PARAMETERS OBTAINED FROM A SOURCE EXTERNAL
027876,000038: # TO THE LEM AND COMPUTE THERE FROM THE REQUIRED-VELOCITY AND
027877,000039: # OTHER INITIAL CONDITIONS REQUIRED BY LM FOR DESIRED MANEUVER.
027878,000040: # THE TARGETING PARAMETERS ARE TIG (TIME OF IGNITION), TARGET
027879,000041: # VECTOR (RTARG), AND THE TIME FROM TIG UNTIL THE TARGET IS
027880,000042: # REACHED (DELLT4), DESIRED TIME OF FLIGHT FROM RINIT TO RTARG.
027881,000043:
027882,000044: # ASSUMPTIONS **
027883,000045:
027884,000046: # 1. THE TARGET PARAMETERS MAY HAVE BEEN LOADED PRIOR TO THE
027885,000047: # EXECUTION OF THIS PROGRAM.
027886,000048: # 2. THIS PROGRAM IS APPLICABLE IN EITHER EARTH OR LUNAR ORBIT.
027887,000049: # 3. THIS PROGRAM IS DESIGNED FOR ONE-MAN OPERATION, AND SHOULD
027888,000050: # BE SELECTED BY THE ASTRONAUT BY DSKY ENTRY V37 E31.
027889,000051:
027890,000052: # SUBROUTINES USED **
027891,000053: #
027892,000054: # MANUPARM, TTG/N35, R02BOTH, MIDGIM, DISPMGA, FLAGDOWN, BANKCALL,
027893,000055: # GOTOPOOH, ENDOFJOB, PHASCHNG, GOFLASHR, GOFLASH.
027894,000056:
027895,000057: # MANUPARM CALCULATES APOGEE, PERIGEE ALTITUDES AND DELTAV DESIRED
027896,000058: # FOR THE MANEUVER.
027897,000059:
027898,000060: # TTG/N35 CLOCKTASK - UPDATES CLOCK.
027899,000061:
027900,000062: # MIDGIM CALCULATES MIDDLE GIMBAL ANGLE FOR DISPLAY.
027901,000063:
027902,000064: # R02BOTH IMU - STATUS CHECK ROUTINE.
027903,000065:
027904,000066: # DISPLAYS USED IN P-31LM **
027905,000067:
027906,000068: # V06N33 DISPLAY SOTRED TIG (IN HRS. MINS. SECS.)
027907,000069: # V06N42 DISPLAY APOGEE, PERIGEE, DELTAV.
027908,000070: # V16N35 DISPLAY TIME FROM TIG.
027909,000071: # V06N45 TIME FROM IGNITION AND MIDDLE GIMBAL ANGLE.
027910,000072:
027911,000073: # ERASABLE INITIALIZATION REQUIRED **
027912,000074:
027913,000075: # TIG TIME OF IGNITION DP (B+28) CS.
027914,000076:
027915,000077: # DELLT4 DESIRED TIME OF FLIGHT DP (B+28) CS
027916,000078: # FROM RINIT TO RTARG.
027917,000079:
027918,000080: # RTARG RADIUS VECTOR OF TARGET POSITION VECTOR
027919,000081: # RADIUS VECTOR SCALED TO (B+29)METERS IF EARTH ORBIT
027920,000082: # Page 652
027921,000083: # RADIUS VECTOR SCALED TO (B+27)METERS IF MOON ORBIT
027922,000084:
027923,000085: # OUTPUT **
027924,000086:
027925,000087: # HAPO APOGEE ALTITUDE
027926,000088: # HPER PERIGEE ALTITUDE
027927,000089: # VGDISP MAG. OF DELTAV FOR DISPLAY, SCALING B+7 M/CS EARTH
027928,000090: # MAG. OF DELTAV FOR DISPLAY, SCALING B+5 M/CS MOON
027929,000091: # MIDGIM MIDDLE GIMBAL ANGLE
027930,000092: # XDELVFLG RESETS XDELVFLG FOR LAMBERT VG COMPUTATIONS
027931,000093:
027932,000094: # ALARMS OR ABORTS NONE **
027933,000095:
027934,000096: # RESTARTS ARE VIA GROUP 4 **
027935,000097:
027936,000098: 35,2000 SETLOC GLM
027937,000099: 35,2000 BANK
027938,000100:
027939,000101: 35,2450 E7,1470 EBANK= SUBEXIT
027940,000102:
027941,000103: 35,2450 COUNT* $$/P31
027942,000104: 35,2450 02361 P31 TC P20FLGON
027943,000105: 35,2451 32025 CAF V06N33 # T16
027944,000106: 35,2452 03712 TC VNP00H
027945,000107: 35,2453 06037 TC INTPRET
027946,000108: 35,2454 71214 CLEAR DLOAD
027947,000109: 35,2455 00670 UPDATFLG
027948,000110: 35,2456 03442 TIG
027949,000111: 35,2457 34041 STCALL TDEC1 # INTEGRATE STATE VECTORS TO TIG
027950,000112: 35,2460 27057 LEMPREC
027951,000113: 35,2461 40375 VLOAD SETPD
027952,000114: 35,2462 00001 RATT
027953,000115: 35,2463 00001 0D
027954,000116: 35,2464 03642 STORE RTIG
027955,000117: 35,2465 26323 STOVL RINIT
027956,000118: 35,2466 00007 VATT
027957,000119: 35,2467 03650 STORE VTIG
027958,000120: 35,2470 16331 STODL VINIT
027959,000121: 35,2471 32420 P30ZERO
027960,000122: 35,2472 65206 PUSH PDDL # E4 AND NUMIT = 0
027961,000123: 35,2473 03452 DELLT4
027962,000124: 35,2474 66015 DAD SXA,1
027963,000125: 35,2475 03442 TIG
027964,000126: 35,2476 02776 RTX1
027965,000127: 35,2477 03631 STORE TPASS4
027966,000128: 35,2500 45134 SXA,2 CALL
027967,000129: 35,2501 02777 RTX2
027968,000130: 35,2502 22000 INITVEL
027969,000131: 35,2503 41575 VLOAD PUSH
027970,000132: # Page 653
027971,000133: 35,2504 02366 DELVEET3
027972,000134: 35,2505 03656 STORE DELVSIN
027973,000135: 35,2506 43046 ABVAL CLEAR
027974,000136: 35,2507 01267 XDELVFLG
027975,000137: 35,2510 37664 STCALL VGDISP
027976,000138: 35,2511 15733 GET.LVC
027977,000139: 35,2512 63375 VLOAD PDVL
027978,000140: 35,2513 03642 RTIG
027979,000141: 35,2514 02337 VIPRIME
027980,000142: 35,2515 77624 CALL
027981,000143: 35,2516 46316 PERIAPO1
027982,000144: 35,2517 77624 CALL
027983,000145: 35,2520 46426 SHIFTR1
027984,000146: 35,2521 77624 CALL # LIMIT DISPLAY TO 9999.9 N. MI.
027985,000147: 35,2522 45636 MAXCHK
027986,000148: 35,2523 16321 STODL HPER
027987,000149: 35,2524 00005 4D
027988,000150: 35,2525 77624 CALL
027989,000151: 35,2526 46426 SHIFTR1
027990,000152: 35,2527 77624 CALL # LIMIT DISPLAY TO 9999.9 N. MI.
027991,000153: 35,2530 45636 MAXCHK
027992,000154: 35,2531 02317 STORE HAPO
027993,000155: 35,2532 77776 EXIT
027994,000156: 35,2533 33727 CAF V06N81 # DELVLVC
027995,000157: 35,2534 03712 TC VNP00H
027996,000158: 35,2535 32026 CAF V06N42 # HAPO, HPER, VGDISP
027997,000159: 35,2536 03712 TC VNP00H
027998,000160: 35,2537 06037 TC INTPRET
027999,000161: 35,2540 45014 REVN1645 SET CALL # TRKMKCNT, TTOGO, +MGA
028000,000162: 35,2541 01071 FINALFLG
028001,000163: 35,2542 73606 VN1645
028002,000164: 35,2543 77650 GOTO
028003,000165: 35,2544 72540 REVN1645
028004,000166:
028005,000167:
028006,000168: # *** END OF LEMP30S .103 ***
028007,000169:
End of include-file LAMBERT_AIMPOINT_GUIDANCE.agc. Parent file is MAIN.agc