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.
Source Code
|
|
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. |
058986,000002: ## Copyright: Public domain.
058987,000003: ## Filename: RTB_OP_CODES.agc
058988,000004: ## Purpose: A section of Luminary revision 116.
058989,000005: ## It is part of the source code for the Lunar Module's (LM)
058990,000006: ## Apollo Guidance Computer (AGC) for Apollo 12.
058991,000007: ## This file is intended to be a faithful transcription, except
058992,000008: ## that the code format has been changed to conform to the
058993,000009: ## requirements of the yaYUL assembler rather than the
058994,000010: ## original YUL assembler.
058995,000011: ## Reference: pp. 1387-1392
058996,000012: ## Assembler: yaYUL
058997,000013: ## Contact: Ron Burkey <info@sandroid.org>.
058998,000014: ## Website: www.ibiblio.org/apollo/index.html
058999,000015: ## Mod history: 2017-01-22 MAS Created from Luminary 99.
059000,000016: ## 2017-02-09 RRB Updated for Luminary 116.
059001,000017: ## 2017-03-14 RSB Proofed comment text via 3-way diff vs
059002,000018: ## Luminary 99 and 131 ... no problems found.
059003,000019:
|
|
Page 1387 |
059005,000021: 22,3773 BANK 22
059006,000022: 10,2000 SETLOC RTBCODES
059007,000023: 10,2000 BANK
059008,000024:
059009,000025: 10,3574 E5,1664 EBANK= XNB
059010,000026: 10,3574 COUNT* $$/RTB
059011,000027:
059012,000028: # LOAD TIME2, TIME1 INTO MPAC:
059013,000029:
059014,000030: 10,3574 00006 LOADTIME EXTEND
059015,000031: 10,3575 30025 DCA TIME2
059016,000032: 10,3576 16060 TCF SLOAD2
059017,000033:
059018,000034: # CONVERT THE SINGLE PRECISION 2'S COMPLEMENT NUMBER ARRIVING IN MPAC (SCALED IN HALF-REVOLUTIONS) TO A
059019,000035: # DP 1'S COMPLEMENT NUMBER SCALED IN REVOLUTIONS.
059020,000036:
059021,000037: 10,3577 10154 CDULOGIC CCS MPAC
059022,000038: 10,3600 34755 CAF ZERO
059023,000039: 10,3601 13604 TCF +3
059024,000040: 10,3602 13603 NOOP
059025,000041: 10,3603 44736 CS HALF
059026,000042:
059027,000043: 10,3604 54155 TS MPAC +1
059028,000044: 10,3605 34755 CAF ZERO
059029,000045: 10,3606 56154 XCH MPAC
059030,000046: 10,3607 00006 EXTEND
059031,000047: 10,3610 74736 MP HALF
059032,000048: 10,3611 20155 DAS MPAC
059033,000049: 10,3612 16064 TCF DANZIG # MODE IS ALREADY AT DOUBLE-PRECISION
059034,000050:
059035,000051: # FORCE TP SIGN AGREEMENT IN MPAC:
059036,000052:
059037,000053: 10,3613 07262 SGNAGREE TC TPAGREE
059038,000054: 10,3614 16064 TCF DANZIG
059039,000055:
059040,000056: # CONVERT THE DP 1'S COMPLEMENT ANGLE SCALED IN REVOLUTIONS TO A SINGLE PRECISION 2'S COMPLEMENT ANGLE
059041,000057: # SCALED IN HALF-REVOLUTIONS.
059042,000058:
059043,000059: 10,3615 03645 1STO2S TC 1TO2SUB
059044,000060: 10,3616 34755 CAF ZERO
059045,000061: 10,3617 54155 TS MPAC +1
059046,000062: 10,3620 16063 TCF NEWMODE
059047,000063:
059048,000064: # DO 1STO2S ON A VECTOR OF ANGLES:
059049,000065:
059050,000066: 10,3621 03645 V1STO2S TC 1TO2SUB # ANSWER ARRIVES IN A AND MPAC.
059051,000067:
059052,000068: 10,3622 52162 DXCH MPAC +5
059053,000069: 10,3623 52155 DXCH MPAC
059054,000070: 10,3624 03645 TC 1TO2SUB
|
|
Page 1388 |
059056,000072: 10,3625 54156 TS MPAC +2
059057,000073:
059058,000074: 10,3626 52160 DXCH MPAC +3
059059,000075: 10,3627 52155 DXCH MPAC
059060,000076: 10,3630 03645 TC 1TO2SUB
059061,000077: 10,3631 54155 TS MPAC +1
059062,000078:
059063,000079: 10,3632 30161 CA MPAC +5
059064,000080: 10,3633 54154 TS MPAC
059065,000081:
059066,000082: 10,3634 34753 TPMODE CAF ONE # MODE IS TP.
059067,000083: 10,3635 16063 TCF NEWMODE
059068,000084:
059069,000085: # V1STO2S FOR 2 COMPONENT VECTOR. USED BY RR.
059070,000086:
059071,000087: 10,3636 03645 2V1STO2S TC 1TO2SUB
059072,000088: 10,3637 52160 DXCH MPAC +3
059073,000089: 10,3640 52155 DXCH MPAC
059074,000090: 10,3641 03645 TC 1TO2SUB
059075,000091: 10,3642 54001 TS L
059076,000092: 10,3643 30157 CA MPAC +3
059077,000093: 10,3644 16060 TCF SLOAD2
059078,000094:
059079,000095: # SUBROUTINE TO DO DOUBLING AND 1'S TO 2'S CONVERSION:
059080,000096:
059081,000097: 10,3645 52155 1TO2SUB DXCH MPAC # FINAL MPAC +1 UNSPECIFIED.
059082,000098: 10,3646 20001 DDOUBL
059083,000099: 10,3647 10000 CCS A
059084,000100: 10,3650 64753 AD ONE
059085,000101: 10,3651 13653 TCF +2
059086,000102: 10,3652 40000 COM # THIS WAS REVERSE OF MSU.
059087,000103:
059088,000104: 10,3653 54154 TS MPAC # AND SKIP ON OVERFLOW.
059089,000105: 10,3654 00002 TC Q
059090,000106:
059091,000107: 10,3655 50000 INDEX A # OVERFLOW UNCORRECT AND IN MSU.
059092,000108: 10,3656 34734 CAF LIMITS
059093,000109: 10,3657 26154 ADS MPAC
059094,000110: 10,3660 00002 TC Q
059095,000111:
059096,000112: # THE FOLLOWING ROUTINE INCREMENTS IN 2S COMPLEMENT THE REGISTER WHOSE ADDRESS IS IN BUF BY THE 1S COMPL.
059097,000113: # QUANTITY FOUND IN TEM2. THIS MAY BE USED TO INCREMENT DESIRED IMU AND OPTICS CDU ANGLES OR ANY OTHER 2S COMPL.
059098,000114: # (+0 UNEQUAL TO -0) QUANTITY. MAY BE CALLED BY BANKCALL/SWCALL.
059099,000115:
059100,000116: 10,3661 54142 CDUINC TS TEM2 # 1S COMPL.QUANT. ARRIVES IN ACC. STORE IT
059101,000117: 10,3662 50130 INDEX BUF
059102,000118: 10,3663 10000 CCS 0 # CHANGE 2S COMPL. ANGLE(IN BUF)INTO 1S
059103,000119: 10,3664 64753 AD ONE
059104,000120: 10,3665 13671 TCF +4
059105,000121: 10,3666 64753 AD ONE
|
|
Page 1389 |
059107,000123: 10,3667 64753 AD ONE # OVERFLOW HERE IF 2S COMPL. IS 180 DEG.
059108,000124: 10,3670 40000 COM
059109,000125:
059110,000126: 10,3671 60142 AD TEM2 # SULT MOVES FROM 2ND TO 3D QUAD. (OR BACK)
059111,000127: 10,3672 10000 CCS A # BACK TO 2S COMPL.
059112,000128: 10,3673 64753 AD ONE
059113,000129: 10,3674 13676 TCF +2
059114,000130: 10,3675 40000 COM
059115,000131: 10,3676 54142 TS TEM2 # STORE 14BIT QUANTITY WITH PRESENT SIGN
059116,000132: 10,3677 13703 TCF +4
059117,000133: 10,3700 50000 INDEX A # SIGN.
059118,000134: 10,3701 34734 CAF LIMITS # FIX IT, BY ADDING IN 37777 OR 40000
059119,000135: 10,3702 60142 AD TEM2
059120,000136:
059121,000137: 10,3703 50130 INDEX BUF
059122,000138: 10,3704 54000 TS 0 # STORE NEW ANGLE IN 2S COMPLEMENT.
059123,000139: 10,3705 00002 TC Q
059124,000140:
|
|
Page 1390 |
059126,000142: # RTB TO TORQUE GYROS, EXCEPT FOR THE CALL TO IMUSTALL. ECADR OF COMMANDS ARRIVES IN X1.
059127,000143:
059128,000144: 10,3706 50120 PULSEIMU INDEX FIXLOC # ADDRESS OF GYRO COMMANDS SHOULD BE IN X1
059129,000145: 10,3707 30046 CA X1
059130,000146: 10,3710 04616 TC BANKCALL
059131,000147: 10,3711 17315 CADR IMUPULSE
059132,000148: 10,3712 16064 TCF DANZIG
059133,000149:
|
|
Page 1391 |
059135,000151: # THE SUBROUTINE SIGNMPAC SETS C(MPAC, MPAC +1) TO SIGN(MPAC).
059136,000152: # FOR THIS, ONLY THE CONTENTS OF MPAC ARE EXAMINED. ALSO +0 YIELDS POSMAX AND -0 YIELDS NEGMAX.
059137,000153:
059138,000154: # ENTRY MAY BE BY EITHER OF THE FOLLOWING:
059139,000155:
059140,000156: # 1. LIMIT THE SIZE OF MPAC ON INTERPRETIVE OVERFLOW:
059141,000157: # ENTRY: BOVB
059142,000158: # SIGNMPAC
059143,000159:
059144,000160: # 2. GENERATE IN MPAC THE SIGNUM FUNCTION OF MPAC:
059145,000161: # ENTRY: RTB
059146,000162: # SIGNMPAC
059147,000163:
059148,000164: # IN EITHER CASE, RETURN IS TO THE NEXT INTERPRETIVE INSTRUCTION IN THE CALLING SEQUENCE.
059149,000165:
059150,000166: 10,3713 00006 SIGNMPAC EXTEND
059151,000167: 10,3714 34733 DCA DPOSMAX
059152,000168: 10,3715 52155 DXCH MPAC
059153,000169: 10,3716 10000 CCS A
059154,000170: 10,3717 34755 DPMODE CAF ZERO # SETS MPAC +2 TO ZERO IN THE PROCESS
059155,000171: 10,3720 16062 TCF SLOAD2 +2
059156,000172: 10,3721 13722 TCF +1
059157,000173: 10,3722 00006 EXTEND
059158,000174: 10,3723 44733 DCS DPOSMAX
059159,000175: 10,3724 16060 TCF SLOAD2
059160,000176:
059161,000177: # RTB OP CODE NORMUNIT IS LIKE INTERPRETIVE INSTRUCTION UNIT, EXCEPT THAT IT CAN BE DEPENDED ON NOT TO BLOW
059162,000178: # UP WHEN THE VECTOR BEING UNITIZED IS VERY SMALL -- IT WILL BLOW UP WHEN ALL COMPONENTS ARE ZERO. IF NORMUNIT
059163,000179: # IS USED AND THE UPPER ORDER HALVES OF ALL COMPONENTS ARE ZERO, THE MAGNITUDE RETURNED IN 36D WILL BE TOO LARGE
059164,000180: # BY A FACTOR OF 2(13) AND THE SQUARED MAGNITUDE RETURNED AT 34D WILL BE TOO BIG BY A FACTOR OF 2(26).
059165,000181:
059166,000182: 10,3725 34753 NORMUNX1 CAF ONE
059167,000183: 10,3726 13730 TCF NORMUNIT +1
059168,000184: 10,3727 34755 NORMUNIT CAF ZERO
059169,000185: 10,3730 60120 AD FIXLOC
059170,000186: 10,3731 54156 TS MPAC +2
059171,000187: 10,3732 04616 TC BANKCALL # GET SIGN AGREEMENT IN ALL COMPONENTS
059172,000188: 10,3733 01010 CADR VECAGREE
059173,000189: 10,3734 10154 CCS MPAC
059174,000190: 10,3735 13771 TCF NOSHIFT
059175,000191: 10,3736 13740 TCF +2
059176,000192: 10,3737 13771 TCF NOSHIFT
059177,000193: 10,3740 10157 CCS MPAC +3
059178,000194: 10,3741 13771 TCF NOSHIFT
059179,000195: 10,3742 13744 TCF +2
059180,000196: 10,3743 13771 TCF NOSHIFT
059181,000197: 10,3744 10161 CCS MPAC +5
059182,000198: 10,3745 13771 TCF NOSHIFT
059183,000199: 10,3746 13750 TCF +2
059184,000200: 10,3747 13771 TCF NOSHIFT
|
|
Page 1392 |
059186,000202: 10,3750 30155 CA MPAC +1 # SHIFT ALL COMPONENTS LEFT 13
059187,000203: 10,3751 00006 EXTEND
059188,000204: 10,3752 74736 MP BIT14
059189,000205: 10,3753 20155 DAS MPAC # DAS GAINS A LITTLE ACCURACY
059190,000206: 10,3754 30160 CA MPAC +4
059191,000207: 10,3755 00006 EXTEND
059192,000208: 10,3756 74736 MP BIT14
059193,000209: 10,3757 20160 DAS MPAC +3
059194,000210: 10,3760 30162 CA MPAC +6
059195,000211: 10,3761 00006 EXTEND
059196,000212: 10,3762 74736 MP BIT14
059197,000213: 10,3763 20162 DAS MPAC +5
059198,000214: 10,3764 34761 CAF THIRTEEN
059199,000215: 10,3765 50156 INDEX MPAC +2
059200,000216: 10,3766 54045 TS 37D
059201,000217: 10,3767 04635 OFFTUNIT TC POSTJUMP
059202,000218: 10,3770 01024 CADR UNIT +1 # SKIP THE "TC VECAGREE" DONE AT UNIT
059203,000219:
059204,000220: 10,3771 34755 NOSHIFT CAF ZERO
059205,000221: 10,3772 13765 TCF OFFTUNIT -2
059206,000222:
059207,000223: # RTB VECSGNAG ... FORCES SIGN AGREEMENT OF VECTOR IN MPAC.
059208,000224:
059209,000225: 10,3773 04616 VECSGNAG TC BANKCALL
059210,000226: 10,3774 01010 CADR VECAGREE
059211,000227: 10,3775 06064 TC DANZIG
059212,000228:
059213,000229:
End of include-file RTB_OP_CODES.agc. Parent file is MAIN.agc