Source Code

020779,000001: # Copyright: Public domain. 020780,000002: # Filename: S-BAND_ANTENNA_FOR_LM.agc 020781,000003: # Purpose: Part of the source code for Luminary 1A build 099. 020782,000004: # It is part of the source code for the Lunar Module's (LM) 020783,000005: # Apollo Guidance Computer (AGC), for Apollo 11. 020784,000006: # Assembler: yaYUL 020785,000007: # Contact: Ron Burkey <info@sandroid.org>. 020786,000008: # Website: www.ibiblio.org/apollo. 020787,000009: # Pages: 486-489 020788,000010: # Mod history: 2009-05-17 RSB Adapted from the corresponding 020789,000011: # Luminary131 file, using page 020790,000012: # images from Luminary 1A. 020791,000013: # 2009-06-07 RSB Corrected a misprint. 020792,000014: 020793,000015: # This source code has been transcribed or otherwise adapted from 020794,000016: # digitized images of a hardcopy from the MIT Museum. The digitization 020795,000017: # was performed by Paul Fjeld, and arranged for by Deborah Douglas of 020796,000018: # the Museum. Many thanks to both. The images (with suitable reduction 020797,000019: # in storage size and consequent reduction in image quality as well) are 020798,000020: # available online at www.ibiblio.org/apollo. If for some reason you 020799,000021: # find that the images are illegible, contact me at info@sandroid.org 020800,000022: # about getting access to the (much) higher-quality images which Paul 020801,000023: # actually created. 020802,000024: 020803,000025: # Notations on the hardcopy document read, in part: 020804,000026: 020805,000027: # Assemble revision 001 of AGC program LMY99 by NASA 2021112-61 020806,000028: # 16:27 JULY 14, 1969 020807,000029: 020808,000030: # Page 486 020809,000031: # SUBROUTINE NAME: R05 -- S-BAND ANTENNA FOR LM 020810,000032: 020811,000033: # MOD0 BY T. JAMES 020812,000034: # MOD1 BY P. SHAKIR 020813,000035: 020814,000036: # FUNCTIONAL DESCRIPTION 020815,000037: 020816,000038: # THE S-BAND ANTENNA ROUTINE, R05, COMPUTES AND DISPLAYS THE PITCH AND 020817,000039: # YAW ANTENNA GIMBAL ANGLES REQUIRED TO POINT THE LM STEERABLE ANTENNA 020818,000040: # TOWARD THE CENTER OF THE EARTH. THIS ROUTINE IS SELECTED BY THE ASTRO- 020819,000041: # NAUT VIA DSKY ENTRY DURING COASTING FLIGHT OR WHEN THE LM IS ON THE MOON 020820,000042: # SURFACE. THE EARTH OR MOON REFERENCE COORDINATE SYSTEM IS USED DEPENDING 020821,000043: # ON WHETHER THE LM IS ABOUT TO ENTER OR HAS ALREADY ENTERED THE MOON 020822,000044: # SPHERE OF INFLUENCE, RESPECTIVELY. 020823,000045: 020824,000046: # TO CALL SUBROUTINE, ASTRONAUT KEYS IN V 64 E 020825,000047: 020826,000048: # SUBROUTINES CALLED --- 020827,000049: # R02BOTH 020828,000050: # INTPRET 020829,000051: # LOADTIME 020830,000052: # LEMCONIC 020831,000053: # LUNPOS 020832,000054: # CDUTRIG 020833,000055: # *SMNB* 020834,000056: # BANKCALL 020835,000057: # B50OFF 020836,000058: # ENDOFJOB 020837,000059: # BLANKRET 020838,000060: 020839,000061: # RETURNS WITH 020840,000062: # PITCH ANGLE IN PITCHANG REV. B0 020841,000063: # YAW ANGLE IN YAWANG REV. B0 020842,000064: 020843,000065: # ERASABLES USED 020844,000066: # PITCHANG 020845,000067: # YAWANG 020846,000068: # RLM 020847,000069: # VAC AREA 020848,000070: 020849,000071: 41,3731 BANK 41 020850,000072: 42,2000 SETLOC SBAND 020851,000073: 42,2000 BANK 020852,000074: 020853,000075: 42,3606 E7,1471 EBANK= WHOCARES 020854,000076: 42,3606 COUNT* $$/R05 020855,000077: 42,3606 04616 SBANDANT TC BANKCALL 020856,000078: # Page 487 020857,000079: 42,3607 11254 CADR R02BOTH # CHECK IF IMU IS ON AND ALIGNED 020858,000080: 42,3610 06037 TC INTPRET 020859,000081: 42,3611 47001 SETPD RTB 020860,000082: 42,3612 00001 0D 020861,000083: 42,3613 21573 LOADTIME # PICK UP CURRENT TIME 020862,000084: 42,3614 34041 STCALL TDEC1 # ADVANCE INTEGRATION TO TIME IN TDEC1 020863,000085: 42,3615 27100 LEMCONIC # USING CONIC INTEGRATION 020864,000086: 42,3616 46135 SLOAD BHIZ 020865,000087: 42,3617 00050 X2 # X2 =0 EARTH SPHERE, X2 =2 MOON SPHERE 020866,000088: 42,3620 65636 CONV4 020867,000089: 42,3621 77775 VLOAD 020868,000090: 42,3622 00001 RATT 020869,000091: 42,3623 16205 STODL RLM 020870,000092: 42,3624 00015 TAT 020871,000093: 42,3625 77624 CONV3 CALL 020872,000094: 42,3626 33664 LUNPOS # UNIT POSITION VECTOR FROM EARTH TO MOON 020873,000095: 42,3627 74375 VLOAD VXSC 020874,000096: 42,3630 02723 VMOON 020875,000097: 42,3631 24001 REMDIST # MEAN DISTANCE FROM EARTH TO MOON 020876,000098: 42,3632 53372 VSL1 VAD 020877,000099: 42,3633 02205 RLM 020878,000100: 42,3634 77650 GOTO 020879,000101: 42,3635 65640 CONV5 020880,000102: 42,3636 77775 CONV4 VLOAD 020881,000103: 42,3637 00001 RATT # UE = -UNIT(RATT) EARTH SPHERE 020882,000104: 42,3640 53401 CONV5 SETPD UNIT # UE = -UNIT((REM)(UEM) + RL) MOON SPHERE 020883,000105: 42,3641 00001 0D # SET PL POINTER TO 0 020884,000106: 42,3642 45076 VCOMP CALL 020885,000107: 42,3643 47537 CDUTRIG # COMPUTE SINES AND COSINES OF CDU ANGLES 020886,000108: 42,3644 76521 MXV VSL1 # TRANSFORM REF. COORDINATE SYSTEM TO 020887,000109: 42,3645 01734 REFSMMAT # STABLE MEMBER B-1 X B-1 X B+1 = B-1 020888,000110: 42,3646 71206 PUSH DLOAD # 8D 020889,000111: 42,3647 06522 HI6ZEROS 020890,000112: 42,3650 02201 STORE PITCHANG 020891,000113: 42,3651 26203 STOVL YAWANG # ZERO OUT ANGLES 020892,000114: 42,3652 77624 CALL 020893,000115: 42,3653 47671 *SMNB* 020894,000116: 42,3654 16205 STODL RLM # PRE-MULTIPLY RLM BY (NBSA) MATRIX(B0) 020895,000117: 42,3655 02207 RLM +2 020896,000118: 42,3656 45206 PUSH DSU 020897,000119: 42,3657 02205 RLM 020898,000120: 42,3660 77605 DMP 020899,000121: 42,3661 25771 1OVSQRT2 020900,000122: 42,3662 16207 STODL RLM +2 020901,000123: 42,3663 41215 DAD DMP 020902,000124: 42,3664 02205 RLM 020903,000125: 42,3665 25771 1OVSQRT2 020904,000126: 42,3666 26205 STOVL RLM # R B-1 020905,000127: 42,3667 02205 RLM 020906,000128: 42,3670 63256 UNIT PDVL 020907,000129: # Page 488 020908,000130: 42,3671 02205 RLM 020909,000131: 42,3672 72431 VPROJ VSL2 # PROJECTION OF R ONTO LM XZ PLANE. 020910,000132: 42,3673 06516 HIUNITY 020911,000133: 42,3674 40045 BVSU BOV # CLEAR OVERFLOW INDICATOR IF ON 020912,000134: 42,3675 02205 RLM 020913,000135: 42,3676 65677 COVCNV 020914,000136: 42,3677 40056 COVCNV UNIT BOV # EXIT ON OVERFLOW 020915,000137: 42,3700 65745 SBANDEX 020916,000138: 42,3701 47206 PUSH VXV # URP VECTOR B-1 020917,000139: 42,3702 06514 HIUNITZ 020918,000140: 42,3703 57572 VSL1 VCOMP # UZ X URP = -(URP X UZ) 020919,000141: 42,3704 02205 STORE RLM # X VEC B-1 020920,000142: 42,3705 63241 DOT PDVL # SGN(X.UY) UNSCALED 020921,000143: 42,3706 06516 HIUNITY 020922,000144: 42,3707 02205 RLM 020923,000145: 42,3710 75246 ABVAL SIGN 020924,000146: 42,3711 77736 ASIN # ASIN((SGN(X.UY))ABV(X)) REV B0 020925,000147: 42,3712 26201 STOVL PITCHANG 020926,000148: 42,3713 00007 URP 020927,000149: 42,3714 51041 DOT BPL 020928,000150: 42,3715 06514 HIUNITZ 020929,000151: 42,3716 65723 NOADJUST # YES, -90 TO +90 020930,000152: 42,3717 45345 DLOAD DSU 020931,000153: 42,3720 06520 HIDPHALF 020932,000154: 42,3721 02201 PITCHANG 020933,000155: 42,3722 02201 STORE PITCHANG 020934,000156: 42,3723 47375 NOADJUST VLOAD VXV 020935,000157: 42,3724 00001 UR # Z = (UR X URP) 020936,000158: 42,3725 00007 URP 020937,000159: 42,3726 77772 VSL1 020938,000160: 42,3727 16205 STODL RLM # Z VEC B-1 020939,000161: 42,3730 02201 PITCHANG 020940,000162: 42,3731 74356 SIN VXSC 020941,000163: 42,3732 06514 HIUNITZ 020942,000164: 42,3733 71525 PDDL COS 020943,000165: 42,3734 02201 PITCHANG 020944,000166: 42,3735 52361 VXSC VSU 020945,000167: 42,3736 06520 HIUNITX # (UX COS ALPHA) - (UZ SIN ALPHA) 020946,000168: 42,3737 63241 DOT PDVL # YAW.Z 020947,000169: 42,3740 02205 RLM 020948,000170: 42,3741 02205 RLM 020949,000171: 42,3742 75246 ABVAL SIGN 020950,000172: 42,3743 77736 ASIN 020951,000173: 42,3744 02203 STORE YAWANG 020952,000174: 42,3745 77776 SBANDEX EXIT 020953,000175: 42,3746 31044 CA EXTVBACT 020954,000176: 42,3747 74747 MASK BIT5 # IS BIT5 STILL ON 020955,000177: 42,3750 00006 EXTEND 020956,000178: 42,3751 15472 BZF ENDEXT # NO 020957,000179: 42,3752 35017 CAF PRIO5 020958,000180: # Page 489 020959,000181: 42,3753 05146 TC PRIOCHNG 020960,000182: 42,3754 33767 CAF V06N51 # DISPLAY ANGLES 020961,000183: 42,3755 04616 TC BANKCALL 020962,000184: 42,3756 20353 CADR GOMARKFR 020963,000185: 42,3757 05563 TC B5OFF # TERMINATE 020964,000186: 42,3760 05563 TC B5OFF # PROCEED 020965,000187: 42,3761 05155 TC ENDOFJOB # RECYCLE 020966,000188: 42,3762 34751 CAF BIT3 # IMMEDIATE RETURN 020967,000189: 42,3763 05464 TC BLANKET # BLANK R3 020968,000190: 42,3764 34740 CAF PRIO4 020969,000191: 42,3765 05146 TC PRIOCHNG 020970,000192: 42,3766 03610 TC SBANDANT +2 # YES, CONTINUE DISPLAYING ANGLES. 020971,000193: 42,3767 01463 V06N51 VN 0651 020972,000194: 42,3770 26501 07463 1OVSQRT2 2DEC .7071067815 # 1/SQRT(2) 020973,000195: 020974,000196: 42,3772 UR EQUALS 0D 020975,000197: 42,3772 URP EQUALS 6D 020976,000198: 42,3772 30,2000 SBANK= LOWSUPER 020977,000199: 020978,000200: # END OF LNYAIDE .001 *** 020979,000201: End of include-file S-BAND_ANTENNA_FOR_LM.agc. Parent file is MAIN.agc