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. |
059959,000002: ## Copyright: Public domain.
059960,000003: ## Filename: RTB_OP_CODES.agc
059961,000004: ## Purpose: Part of the source code for Luminary 1A build 099.
059962,000005: ## It is part of the source code for the Lunar Module's (LM)
059963,000006: ## Apollo Guidance Computer (AGC), for Apollo 11.
059964,000007: ## Assembler: yaYUL
059965,000008: ## Contact: Ron Burkey <info@sandroid.org>.
059966,000009: ## Website: www.ibiblio.org/apollo.
059967,000010: ## Pages: 1397-1401
059968,000011: ## Mod history: 2009-05-10 SN (Sergio Navarro). Started adapting
059969,000012: ## from the Luminary131/ file of the same
059970,000013: ## name, using Luminary099 page images.
059971,000014: ## 2016-12-18 RSB Proofed text comments with octopus/ProoferComments
059972,000015: ## and corrected the errors found.
059973,000016: ##
059974,000017: ## This source code has been transcribed or otherwise adapted from
059975,000018: ## digitized images of a hardcopy from the MIT Museum. The digitization
059976,000019: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
059977,000020: ## the Museum. Many thanks to both. The images (with suitable reduction
059978,000021: ## in storage size and consequent reduction in image quality as well) are
059979,000022: ## available online at www.ibiblio.org/apollo. If for some reason you
059980,000023: ## find that the images are illegible, contact me at info@sandroid.org
059981,000024: ## about getting access to the (much) higher-quality images which Paul
059982,000025: ## actually created.
059983,000026: ##
059984,000027: ## Notations on the hardcopy document read, in part:
059985,000028: ##
059986,000029: ## Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
059987,000030: ## 16:27 JULY 14, 1969
059988,000031:
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Page 1397 |
059990,000033: 22,3773 BANK 22
059991,000034: 10,2000 SETLOC RTBCODES
059992,000035: 10,2000 BANK
059993,000036:
059994,000037: 10,3573 E5,1664 EBANK= XNB
059995,000038: 10,3573 COUNT* $$/RTB
059996,000039:
059997,000040: # LOAD TIME2, TIME1 INTO MPAC:
059998,000041:
059999,000042: 10,3573 00006 LOADTIME EXTEND
060000,000043: 10,3574 30025 DCA TIME2
060001,000044: 10,3575 16055 TCF SLOAD2
060002,000045:
060003,000046: # CONVERT THE SINGLE PRECISION 2'S COMPLEMENT NUMBER ARRIVING IN MPAC (SCALED IN HALF-REVOLUTIONS) TO A
060004,000047: # DP 1'S COMPLEMENT NUMBER SCALED IN REVOLUTIONS.
060005,000048:
060006,000049: 10,3576 10154 CDULOGIC CCS MPAC
060007,000050: 10,3577 34755 CAF ZERO
060008,000051: 10,3600 13603 TCF +3
060009,000052: 10,3601 13602 NOOP
060010,000053: 10,3602 44736 CS HALF
060011,000054:
060012,000055: 10,3603 54155 TS MPAC +1
060013,000056: 10,3604 34755 CAF ZERO
060014,000057: 10,3605 56154 XCH MPAC
060015,000058: 10,3606 00006 EXTEND
060016,000059: 10,3607 74736 MP HALF
060017,000060: 10,3610 20155 DAS MPAC
060018,000061: 10,3611 16061 TCF DANZIG # MODE IS ALREADY AT DOUBLE-PRECISION
060019,000062:
060020,000063: # FORCE TP SIGN AGREEMENT IN MPAC:
060021,000064:
060022,000065: 10,3612 07257 SGNAGREE TC TPAGREE
060023,000066: 10,3613 16061 TCF DANZIG
060024,000067:
060025,000068: # CONVERT THE DP 1'S COMPLEMENT ANGLE SCALED IN REVOLUTIONS TO A SINGLE PRECISION 2'S COMPLEMENT ANGLE
060026,000069: # SCALED IN HALF-REVOLUTIONS.
060027,000070:
060028,000071: 10,3614 03644 1STO2S TC 1TO2SUB
060029,000072: 10,3615 34755 CAF ZERO
060030,000073: 10,3616 54155 TS MPAC +1
060031,000074: 10,3617 16060 TCF NEWMODE
060032,000075:
060033,000076: # DO 1STO2S ON A VECTOR OF ANGLES:
060034,000077:
060035,000078: 10,3620 03644 V1STO2S TC 1TO2SUB # ANSWER ARRIVES IN A AND MPAC.
060036,000079:
060037,000080: 10,3621 52162 DXCH MPAC +5
060038,000081: 10,3622 52155 DXCH MPAC
060039,000082: 10,3623 03644 TC 1TO2SUB
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Page 1398 |
060041,000084: 10,3624 54156 TS MPAC +2
060042,000085:
060043,000086: 10,3625 52160 DXCH MPAC +3
060044,000087: 10,3626 52155 DXCH MPAC
060045,000088: 10,3627 03644 TC 1TO2SUB
060046,000089: 10,3630 54155 TS MPAC +1
060047,000090:
060048,000091: 10,3631 30161 CA MPAC +5
060049,000092: 10,3632 54154 TS MPAC
060050,000093:
060051,000094: 10,3633 34753 TPMODE CAF ONE # MODE IS TP.
060052,000095: 10,3634 16060 TCF NEWMODE
060053,000096:
060054,000097: # V1STO2S FOR 2 COMPONENT VECTOR. USED BY RR.
060055,000098:
060056,000099: 10,3635 03644 2V1STO2S TC 1TO2SUB
060057,000100: 10,3636 52160 DXCH MPAC +3
060058,000101: 10,3637 52155 DXCH MPAC
060059,000102: 10,3640 03644 TC 1TO2SUB
060060,000103: 10,3641 54001 TS L
060061,000104: 10,3642 30157 CA MPAC +3
060062,000105: 10,3643 16055 TCF SLOAD2
060063,000106:
060064,000107: # SUBROUTINE TO DO DOUBLING AND 1'S TO 2'S CONVERSION:
060065,000108:
060066,000109: 10,3644 52155 1TO2SUB DXCH MPAC # FINAL MPAC +1 UNSPECIFIED.
060067,000110: 10,3645 20001 DDOUBL
060068,000111: 10,3646 10000 CCS A
060069,000112: 10,3647 64753 AD ONE
060070,000113: 10,3650 13652 TCF +2
060071,000114: 10,3651 40000 COM # THIS WAS REVERSE OF MSU.
060072,000115:
060073,000116: 10,3652 54154 TS MPAC # AND SKIP ON OVERFLOW.
060074,000117: 10,3653 00002 TC Q
060075,000118:
060076,000119: 10,3654 50000 INDEX A # OVERFLOW UNCORRECT AND IN MSU.
060077,000120: 10,3655 34734 CAF LIMITS
060078,000121: 10,3656 26154 ADS MPAC
060079,000122: 10,3657 00002 TC Q
060080,000123:
060081,000124: # THE FOLLOWING ROUTINE INCREMENTS IN 2S COMPLEMENT THE REGISTER WHOSE ADDRESS IS IN BUF BY THE 1S COMPL.
060082,000125: # QUANTITY FOUND IN TEM2. THIS MAY BE USED TO INCREMENT DESIRED IMU AND OPTICS CDU ANGLES OR ANY OTHER 2S COMPL.
060083,000126: # (+0 UNEQUAL TO -0) QUANTITY. MAY BE CALLED BY BANKCALL/SWCALL.
060084,000127:
060085,000128: 10,3660 54142 CDUINC TS TEM2 # 1S COMPL.QUANT. ARRIVES IN ACC. STORE IT
060086,000129: 10,3661 50130 INDEX BUF
060087,000130: 10,3662 10000 CCS 0 # CHANGE 2S COMPL. ANGLE(IN BUF)INTO 1S
060088,000131: 10,3663 64753 AD ONE
060089,000132: 10,3664 13670 TCF +4
060090,000133: 10,3665 64753 AD ONE
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Page 1399 |
060092,000135: 10,3666 64753 AD ONE # OVERFLOW HERE IF 2S COMPL. IS 180 DEG.
060093,000136: 10,3667 40000 COM
060094,000137:
060095,000138: 10,3670 60142 AD TEM2 # SULT MOVES FROM 2ND TO 3D QUAD. (OR BACK)
060096,000139: 10,3671 10000 CCS A # BACK TO 2S COMPL.
060097,000140: 10,3672 64753 AD ONE
060098,000141: 10,3673 13675 TCF +2
060099,000142: 10,3674 40000 COM
060100,000143: 10,3675 54142 TS TEM2 # STORE 14BIT QUANTITY WITH PRESENT SIGN
060101,000144: 10,3676 13702 TCF +4
060102,000145: 10,3677 50000 INDEX A # SIGN.
060103,000146: 10,3700 34734 CAF LIMITS # FIX IT, BY ADDING IN 37777 OR 40000
060104,000147: 10,3701 60142 AD TEM2
060105,000148:
060106,000149: 10,3702 50130 INDEX BUF
060107,000150: 10,3703 54000 TS 0 # STORE NEW ANGLE IN 2S COMPLEMENT.
060108,000151: 10,3704 00002 TC Q
060109,000152:
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Page 1400 |
060111,000154: # RTB TO TORQUE GYROS, EXCEPT FOR THE CALL TO IMUSTALL. ECADR OF COMMANDS ARRIVES IN X1.
060112,000155:
060113,000156: 10,3705 50120 PULSEIMU INDEX FIXLOC # ADDRESS OF GYRO COMMANDS SHOULD BE IN X1
060114,000157: 10,3706 30046 CA X1
060115,000158: 10,3707 04616 TC BANKCALL
060116,000159: 10,3710 17323 CADR IMUPULSE
060117,000160: 10,3711 16061 TCF DANZIG
060118,000161:
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Page 1401 |
060120,000163: # THE SUBROUTINE SIGNMPAC SETS C(MPAC, MPAC +1) TO SIGN(MPAC).
060121,000164: # FOR THIS, ONLY THE CONTENTS OF MPAC ARE EXAMINED. ALSO +0 YIELDS POSMAX AND -0 YIELDS NEGMAX.
060122,000165:
060123,000166: # ENTRY MAY BE BY EITHER OF THE FOLLOWING:
060124,000167: # 1. LIMIT THE SIZE OF MPAC ON INTERPRETIVE OVERFLOW:
060125,000168: # ENTRY: BOVB
060126,000169: # SIGNMPAC
060127,000170: # 2. GENERATE IN MPAC THE SIGNUM FUNCTION OF MPAC:
060128,000171: # ENTRY: RTB
060129,000172: # SIGNMPAC
060130,000173: # IN EITHER CASE, RETURN IS TO THE NEXT INTERPRETIVE INSTRUCTION IN THE CALLING SEQUENCE.
060131,000174:
060132,000175: 10,3712 00006 SIGNMPAC EXTEND
060133,000176: 10,3713 34733 DCA DPOSMAX
060134,000177: 10,3714 52155 DXCH MPAC
060135,000178: 10,3715 10000 CCS A
060136,000179: 10,3716 34755 DPMODE CAF ZERO # SETS MPAC +2 TO ZERO IN THE PROCESS
060137,000180: 10,3717 16057 TCF SLOAD2 +2
060138,000181: 10,3720 13721 TCF +1
060139,000182: 10,3721 00006 EXTEND
060140,000183: 10,3722 44733 DCS DPOSMAX
060141,000184: 10,3723 16055 TCF SLOAD2
060142,000185:
060143,000186: # RTB OP CODE NORMUNIT IS LIKE INTERPRETIVE INSTRUCTION UNIT, EXCEPT THAT IT CAN BE DEPENDED ON NOT TO BLOW
060144,000187: # UP WHEN THE VECTOR BEING UNITIZED IS VERY SMALL -- IT WILL BLOW UP WHEN ALL COMPONENTS ARE ZERO. IF NORMUNIT
060145,000188: # IS USED AND THE UPPER ORDER HALVES OF ALL COMPONENTS ARE ZERO, THE MAGNITUDE RETURNED IN 36D WILL BE TOO LARGE
060146,000189: # BY A FACTOR OF 2(13) AND THE SQUARED MAGNITUDE RETURNED AT 34D WILL BE TOO BIG BY A FACTOR OF 2(26).
060147,000190:
060148,000191: 10,3724 34753 NORMUNX1 CAF ONE
060149,000192: 10,3725 13727 TCF NORMUNIT +1
060150,000193: 10,3726 34755 NORMUNIT CAF ZERO
060151,000194: 10,3727 60120 AD FIXLOC
060152,000195: 10,3730 54156 TS MPAC +2
060153,000196: 10,3731 04616 TC BANKCALL # GET SIGN AGREEMENT IN ALL COMPONENTS
060154,000197: 10,3732 01010 CADR VECAGREE
060155,000198: 10,3733 10154 CCS MPAC
060156,000199: 10,3734 13770 TCF NOSHIFT
060157,000200: 10,3735 13737 TCF +2
060158,000201: 10,3736 13770 TCF NOSHIFT
060159,000202: 10,3737 10157 CCS MPAC +3
060160,000203: 10,3740 13770 TCF NOSHIFT
060161,000204: 10,3741 13743 TCF +2
060162,000205: 10,3742 13770 TCF NOSHIFT
060163,000206: 10,3743 10161 CCS MPAC +5
060164,000207: 10,3744 13770 TCF NOSHIFT
060165,000208: 10,3745 13747 TCF +2
060166,000209: 10,3746 13770 TCF NOSHIFT
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Page 1402 |
060168,000211: 10,3747 30155 CA MPAC +1 # SHIFT ALL COMPONENTS LEFT 13
060169,000212: 10,3750 00006 EXTEND
060170,000213: 10,3751 74736 MP BIT14
060171,000214: 10,3752 20155 DAS MPAC # DAS GAINS A LITTLE ACCURACY
060172,000215: 10,3753 30160 CA MPAC +4
060173,000216: 10,3754 00006 EXTEND
060174,000217: 10,3755 74736 MP BIT14
060175,000218: 10,3756 20160 DAS MPAC +3
060176,000219: 10,3757 30162 CA MPAC +6
060177,000220: 10,3760 00006 EXTEND
060178,000221: 10,3761 74736 MP BIT14
060179,000222: 10,3762 20162 DAS MPAC +5
060180,000223: 10,3763 34761 CAF THIRTEEN
060181,000224: 10,3764 50156 INDEX MPAC +2
060182,000225: 10,3765 54045 TS 37D
060183,000226: 10,3766 04635 OFFTUNIT TC POSTJUMP
060184,000227: 10,3767 01024 CADR UNIT +1 # SKIP THE "TC VECAGREE" DONE AT UNIT
060185,000228:
060186,000229: 10,3770 34755 NOSHIFT CAF ZERO
060187,000230: 10,3771 13764 TCF OFFTUNIT -2
060188,000231:
060189,000232: # RTB VECSGNAG ... FORCES SIGN AGREEMENT OF VECTOR IN MPAC.
060190,000233:
060191,000234: 10,3772 04616 VECSGNAG TC BANKCALL
060192,000235: 10,3773 01010 CADR VECAGREE
060193,000236: 10,3774 06061 TC DANZIG
060194,000237:
060195,000238:
End of include-file RTB_OP_CODES.agc. Parent file is MAIN.agc