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. |
020815,000002: ## Copyright: Public domain.
020816,000003: ## Filename: S-BAND_ANTENNA_FOR_LM.agc
020817,000004: ## Purpose: A section of Luminary revision 116.
020818,000005: ## It is part of the source code for the Lunar Module's (LM)
020819,000006: ## Apollo Guidance Computer (AGC) for Apollo 12.
020820,000007: ## This file is intended to be a faithful transcription, except
020821,000008: ## that the code format has been changed to conform to the
020822,000009: ## requirements of the yaYUL assembler rather than the
020823,000010: ## original YUL assembler.
020824,000011: ## Reference: pp. 488-491
020825,000012: ## Assembler: yaYUL
020826,000013: ## Contact: Ron Burkey <info@sandroid.org>.
020827,000014: ## Website: www.ibiblio.org/apollo/index.html
020828,000015: ## Mod history: 2017-01-22 MAS Created from Luminary 99.
020829,000016: ## 2017-03-09 RSB Transcribed, and then proofed comment-text using
020830,000017: ## 3-way diff vs Luminary 99 and Luminary 131.
020831,000018: ## (Admittedly, the former is more for detecting errors
020832,000019: ## in Luminary 99 than the other way around.)
020833,000020: ## 2017-03-13 HG Remove operand modifier SBANDANT +2 --> SBANDANT
020834,000021:
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Page 488 |
020836,000023: # SUBROUTINE NAME: R05 - S-BAND ANTENNA FOR LM
020837,000024:
020838,000025: # MOD0 BY T. JAMES
020839,000026: # MOD1 BY P. SHAKIR
020840,000027:
020841,000028: # FUNCTIONAL DESCRIPTION
020842,000029:
020843,000030: # THE S-BAND ANTENNA ROUTINE, R05, COMPUTES AND DISPLAYS THE PITCH AND
020844,000031: # YAW ANTENNA GIMBAL ANGLES REQUIRED TO POINT THE LM STEERABLE ANTENNA
020845,000032: # TOWARD THE CENTER OF THE EARTH. THIS ROUTINE IS SELECTED BY THE ASTRO-
020846,000033: # NAUT VIA DSKY ENTRY DURING COASTING FLIGHT OR WHEN THE LM IS ON THE MOON
020847,000034: # SURFACE. THE EARTH OR MOON REFERENCE COORDINATE SYSTEM IS USED DEPENDING
020848,000035: # ON WHETHER THE LM IS ABOUT TO ENTER OR HAS ALREADY ENTERED THE MOON
020849,000036: # SPHERE OF INFLUENCE, RESPECTIVELY. CAN BE CALLED ANY TIME EXCEPT WHEN
020850,000037: # ANOTHER EXTENDED VERB IS IN USE. DISPLAY IS MEANINGLESS WITH IMU OFF.
020851,000038:
020852,000039: # TO CALL SUBROUTINE, ASTRONAUT KEYS IN V 64 E
020853,000040:
020854,000041: # SUBROUTINES CALLED -
020855,000042:
020856,000043: # INTPRET
020857,000044: # LOADTIME
020858,000045: # LEMCONIC
020859,000046: # LUNPOS
020860,000047: # CDUTRIG
020861,000048: # *SMNB*
020862,000049: # BANKCALL
020863,000050: # B5OFF
020864,000051: # ENDOFJOB
020865,000052: # BLANKET
020866,000053:
020867,000054: # RETURNS WITH
020868,000055:
020869,000056: # PITCH ANGLE IN PITCHANG REV. B0
020870,000057: # YAW ANGLE IN YAWANG REV. B0
020871,000058:
020872,000059: # ERASABLES USED
020873,000060: # PITCHANG
020874,000061: # YAWANG
020875,000062: # RLM
020876,000063: # VAC AREA
020877,000064:
020878,000065: 41,3743 BANK 41
020879,000066: 42,2000 SETLOC SBAND
020880,000067: 42,2000 BANK
020881,000068:
020882,000069: 42,3606 E7,1471 EBANK= WHOCARES
020883,000070: 42,3606 COUNT* $$/R05
020884,000071: 42,3606 06042 SBANDANT TC INTPRET
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Page 489 |
020886,000073: 42,3607 47001 SETPD RTB
020887,000074: 42,3610 00001 0D
020888,000075: 42,3611 21574 LOADTIME # PICK UP CURRENT TIME
020889,000076: 42,3612 34041 STCALL TDEC1 # ADVANCE INTEGRATION TO TIME IN TDEC1
020890,000077: 42,3613 27101 LEMCONIC # USING CONIC INTEGRATION
020891,000078: 42,3614 46135 SLOAD BHIZ
020892,000079: 42,3615 00050 X2 # X2 =0 EARTH SPHERE, X2 =2 MOON SPHERE
020893,000080: 42,3616 65634 CONV4
020894,000081: 42,3617 77775 VLOAD
020895,000082: 42,3620 00001 RATT
020896,000083: 42,3621 16205 STODL RLM
020897,000084: 42,3622 00015 TAT
020898,000085: 42,3623 77624 CONV3 CALL
020899,000086: 42,3624 33647 LUNPOS # UNIT POSITION VECTOR FROM EARTH TO MOON
020900,000087: 42,3625 74375 VLOAD VXSC
020901,000088: 42,3626 02723 VMOON
020902,000089: 42,3627 24001 REMDIST # MEAN DISTANCE FROM EARTH TO MOON
020903,000090: 42,3630 53372 VSL1 VAD
020904,000091: 42,3631 02205 RLM
020905,000092: 42,3632 77650 GOTO
020906,000093: 42,3633 65636 CONV5
020907,000094: 42,3634 77775 CONV4 VLOAD
020908,000095: 42,3635 00001 RATT # UE = -UNIT(RATT) EARTH SPHERE
020909,000096: 42,3636 53401 CONV5 SETPD UNIT # UE = -UNIT((REM)(UEM) + RL) MOON SPHERE
020910,000097: 42,3637 00001 0D # SET PL POINTER TO 0
020911,000098: 42,3640 45076 VCOMP CALL
020912,000099: 42,3641 47541 CDUTRIG # COMPUTE SINES AND COSINES OF CDU ANGLES
020913,000100: 42,3642 76521 MXV VSL1 # TRANSFORM REF. COORDINATE SYSTEM TO
020914,000101: 42,3643 01734 REFSMMAT # STABLE MEMBER B-1 X B-1 X B+1 = B-1
020915,000102: 42,3644 71206 PUSH DLOAD # 8D
020916,000103: 42,3645 06524 HI6ZEROS
020917,000104: 42,3646 02201 STORE PITCHANG
020918,000105: 42,3647 26203 STOVL YAWANG # ZERO OUT ANGLES
020919,000106: 42,3650 77624 CALL
020920,000107: 42,3651 47673 *SMNB*
020921,000108: 42,3652 16205 STODL RLM # PRE-MULTIPLY RLM BY (NBSA) MATRIX(B0)
020922,000109: 42,3653 02207 RLM +2
020923,000110: 42,3654 45206 PUSH DSU
020924,000111: 42,3655 02205 RLM
020925,000112: 42,3656 77605 DMP
020926,000113: 42,3657 25767 1OVSQRT2
020927,000114: 42,3660 16207 STODL RLM +2
020928,000115: 42,3661 41215 DAD DMP
020929,000116: 42,3662 02205 RLM
020930,000117: 42,3663 25767 1OVSQRT2
020931,000118: 42,3664 26205 STOVL RLM # R B-1
020932,000119: 42,3665 02205 RLM
020933,000120: 42,3666 63256 UNIT PDVL
020934,000121: 42,3667 02205 RLM
020935,000122: 42,3670 72431 VPROJ VSL2 # PROJECTION OF R ONTO LM XZ PLANE
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020937,000124: 42,3671 06520 HIUNITY
020938,000125: 42,3672 40045 BVSU BOV # CLEAR OVERFLOW INDICATOR IF ON
020939,000126: 42,3673 02205 RLM
020940,000127: 42,3674 65675 COVCNV
020941,000128: 42,3675 40056 COVCNV UNIT BOV # EXIT ON OVERFLOW
020942,000129: 42,3676 65743 SBANDEX
020943,000130: 42,3677 47206 PUSH VXV # URP VECTOR B-1
020944,000131: 42,3700 06516 HIUNITZ
020945,000132: 42,3701 57572 VSL1 VCOMP # UZ X URP = -(URP X UZ)
020946,000133: 42,3702 02205 STORE RLM # X VEC B-1
020947,000134: 42,3703 63241 DOT PDVL # SGN(X.UY) UNSCALED
020948,000135: 42,3704 06520 HIUNITY
020949,000136: 42,3705 02205 RLM
020950,000137: 42,3706 75246 ABVAL SIGN
020951,000138: 42,3707 77736 ASIN # ASIN((SGN(X.UY))ABV(X)) REV B0
020952,000139: 42,3710 26201 STOVL PITCHANG
020953,000140: 42,3711 00007 URP
020954,000141: 42,3712 51041 DOT BPL
020955,000142: 42,3713 06516 HIUNITZ
020956,000143: 42,3714 65721 NOADJUST # YES, -90 TO +90
020957,000144: 42,3715 45345 DLOAD DSU
020958,000145: 42,3716 06522 HIDPHALF
020959,000146: 42,3717 02201 PITCHANG
020960,000147: 42,3720 02201 STORE PITCHANG
020961,000148: 42,3721 47375 NOADJUST VLOAD VXV
020962,000149: 42,3722 00001 UR # Z = (UR X URP)
020963,000150: 42,3723 00007 URP
020964,000151: 42,3724 77772 VSL1
020965,000152: 42,3725 16205 STODL RLM # Z VEC B-1
020966,000153: 42,3726 02201 PITCHANG
020967,000154: 42,3727 74356 SIN VXSC
020968,000155: 42,3730 06516 HIUNITZ
020969,000156: 42,3731 71525 PDDL COS
020970,000157: 42,3732 02201 PITCHANG
020971,000158: 42,3733 52361 VXSC VSU
020972,000159: 42,3734 06522 HIUNITX # (UX COS ALPHA) - (UZ SIN ALPHA)
020973,000160: 42,3735 63241 DOT PDVL # YAW.Z
020974,000161: 42,3736 02205 RLM
020975,000162: 42,3737 02205 RLM
020976,000163: 42,3740 75246 ABVAL SIGN
020977,000164: 42,3741 77736 ASIN
020978,000165: 42,3742 02203 STORE YAWANG
020979,000166: 42,3743 77776 SBANDEX EXIT
020980,000167: 42,3744 31043 CA EXTVBACT
020981,000168: 42,3745 74747 MASK BIT5 # IS BIT5 STILL ON
020982,000169: 42,3746 00006 EXTEND
020983,000170: 42,3747 15472 BZF ENDEXT # NO
020984,000171: 42,3750 35017 CAF PRIO5
020985,000172: 42,3751 05146 TC PRIOCHNG
020986,000173: 42,3752 33765 CAF V06N51 # DISPLAY ANGLES
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020988,000175: 42,3753 04616 TC BANKCALL
020989,000176: 42,3754 20353 CADR GOMARKFR
020990,000177: 42,3755 05563 TC B5OFF # TERMINATE
020991,000178: 42,3756 05563 TC B5OFF # PROCEED
020992,000179: 42,3757 05155 TC ENDOFJOB # RECYCLE
020993,000180: 42,3760 34751 CAF BIT3 # IMMEDIATE RETURN
020994,000181: 42,3761 05464 TC BLANKET # BLANK R3
020995,000182: 42,3762 34740 CAF PRIO4
020996,000183: 42,3763 05146 TC PRIOCHNG
020997,000184: 42,3764 03606 TC SBANDANT # YES, CONTINUE DISPLAYING ANGLES.
020998,000185: 42,3765 01463 V06N51 VN 0651
020999,000186: 42,3766 26501 07463 1OVSQRT2 2DEC .7071067815 # 1/SQRT(2)
021000,000187:
021001,000188: 42,3770 UR EQUALS 0D
021002,000189: 42,3770 URP EQUALS 6D
021003,000190: 42,3770 30,2000 SBANK= LOWSUPER
End of include-file S-BAND_ANTENNA_FOR_LM.agc. Parent file is MAIN.agc