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. |
065303,000002: ## Copyright: Public domain.
065304,000003: ## Filename: SPS_BACK-UP_RCS_CONTROL.agc
065305,000004: ## Purpose: Part of the source code for Luminary 1A build 099.
065306,000005: ## It is part of the source code for the Lunar Module's (LM)
065307,000006: ## Apollo Guidance Computer (AGC), for Apollo 11.
065308,000007: ## Assembler: yaYUL
065309,000008: ## Contact: Ron Burkey <info@sandroid.org>.
065310,000009: ## Website: www.ibiblio.org/apollo.
065311,000010: ## Pages: 1507-1510
065312,000011: ## Mod history: 2009-05-27 RSB Adapted from the corresponding
065313,000012: ## Luminary131 file, using page
065314,000013: ## images from Luminary 1A.
065315,000014: ## 2011-01-06 JL Fixed pseudo-label indentation.
065316,000015: ## 2016-12-18 RSB Proofed text comments with octopus/ProoferComments
065317,000016: ## and corrected the errors found.
065318,000017: ##
065319,000018: ## This source code has been transcribed or otherwise adapted from
065320,000019: ## digitized images of a hardcopy from the MIT Museum. The digitization
065321,000020: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
065322,000021: ## the Museum. Many thanks to both. The images (with suitable reduction
065323,000022: ## in storage size and consequent reduction in image quality as well) are
065324,000023: ## available online at www.ibiblio.org/apollo. If for some reason you
065325,000024: ## find that the images are illegible, contact me at info@sandroid.org
065326,000025: ## about getting access to the (much) higher-quality images which Paul
065327,000026: ## actually created.
065328,000027: ##
065329,000028: ## Notations on the hardcopy document read, in part:
065330,000029: ##
065331,000030: ## Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
065332,000031: ## 16:27 JULY 14, 1969
065333,000032:
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Page 1507 |
065335,000034: # PROGRAM NAME: SPSRCS
065336,000035: # AUTHOR: EDGAR M. OSHIKA (AC ELECTRONICS)
065337,000036: # MODIFIED: TO RETURN TO ALL AXES VIA Q BY P. S. WEISSMAN, OCT 7, 1968
065338,000037: # MODIFIED TO IMPROVE BENDING STABILITY BY G. KALAN, FEB. 14, 1969
065339,000038:
065340,000039: # FUNCTIONAL DESCRIPTION:
065341,000040: # THIS PROGRAM CONTROLS THE FIRING OF ALL RCS JETS IN THE DOCKED CONFIGURATION ACCORDING TO THE FOLLOWING PHASE
065342,000041: # PLANE LOGIC.
065343,000042:
065344,000043: # 1. JET SENSE TEST (SPSRCS)
065345,000044: # IF JETS ARE FIRING NEGATIVELY, SET OLDSENSE NEGATIVE AND CONTINUE
065346,000045: # IF JETS ARE FIRING POSITIVELY, SET OLDSENSE POSITIVE AND CONTINUE
065347,000046: # IF JETS ARE NOT FIRING, SET OLDSENSE TO ZERO AND GO TO OUTER RATE LIMIT TEST
065348,000047:
065349,000048: # 2. RATE DEAD BAND TEST
065350,000049: # IF JETS ARE FIRING NEGATIVELY AND RATE IS GREATER THAN TARGET RATE, LEAVE
065351,000050: # JETS ON AND GO TO INHIBITION LOGIC. OTHERWISE, CONTINUE.
065352,000051: # IF JETS ARE FIRING POSITIVELY AND RATE IS LESS THAN TARGET RATE, LEAVE
065353,000052: # JETS ON AND GO TO INHIBITION LOGIC. OTHERWISE, CONTINUE.
065354,000053:
065355,000054: # 3. OUTER RATE LIMIT TEST (SPSSTART)
065356,000055: # IF MAGNITUDE OF EDOT IS GREATER THAN 1.73 DEG/SEC SET JET FIRING TIME
065357,000056: # TO REDUCE RATE AND GO TO INHIBITION LOGIC. OTHERWISE, CONTINUE.
065358,000057:
065359,000058: # 4. COAST ZONE TEST
065360,000059: # IF STATE (E,EDOT) IS BELOW LINE E + 4 X EDOT > -1.4 DEG AND EDOT IS LESS THAN 1.30 DEG/SEC SET JET TIME POSI-
065361,000060: # TIVE AND CONTINUE. OTHERWISE, SET JET FIRING TIME TO ZERO AND CONTINUE.
065362,000061: # IF STATE IS ABOVE LINE E + 4 X EDOT > +1.4 DEG AND EDOT IS GREATER THAN -1.30 DEG/SEC, SET JET TIME NEGATIVE
065363,000062: # AND CONTINUE. OTHERWISE, SET JET FIRING TIME TO ZERO AND CONTINUE.
065364,000063:
065365,000064: # 5. INHIBITION LOGIC
065366,000065: # IF OLDSENSE IS NON-ZERO:
065367,000066: # A) RETURN IF JET TIME HAS SAME SIGN AS OLDSENSE
065368,000067: # B) SET INHIBITION COUNTER* AND RETURN IF JET TIME IS ZERO
065369,000068: # C) SET INHIBITION COUNTER,* SET JET TIME TO ZERO AND RETURN IF SIGN
065370,000069: # OF JET TIME IS OPPOSITE TO THAT OF OLDSENSE
065371,000070: # IF OLDSENSE IS ZERO:
065372,000071: # A) RETURN IF INHIBITION COUNTER IS NOT POSITIVE
065373,000072: # B) SET JET TIME TO ZERO AND RETURN IF INHIBITION COUNTER IS POSITIVE
065374,000073: # *NOTE: INHIBITION COUNTERS CAN BE SET TO 4 OR 10 FOR THE P, AND UV AXES,
065375,000074: # RESPECTIVELY, IN SPSRCS. THEY ARE DECREMENTED BY ONE AT THE BEGINNING OF
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Page 1508 |
065377,000076: # EACH DAP PASS.
065378,000077:
065379,000078: # THE MINIMUM PULSE WIDTH OF THIS CONTROLLER IS DETERMINED BY THE REPETITION RATE AT WHICH THIS ROUTINE IS CALLED
065380,000079: # AND IS NOMINALLY 100 MS FOR ALL AXES IN DRIFTING FLIGHT. DURING POWERED FLIGHT THE MINIMUM IS 100 MS FOR THE
065381,000080: # P AXIS AND 200 MS FOR THE CONTROL OF THE U AND V AXES.
065382,000081:
065383,000082: # CALLING SEQUENCE:
065384,000083: # INHINT
065385,000084: # TC IBNKCALL
065386,000085: # CADR SPSRCS
065387,000086:
065388,000087: # EXIT:
065389,000088: # TC Q
065390,000089:
065391,000090: # ALARM/ABORT MODE: NONE
065392,000091:
065393,000092: # SUBROUTINES CALLED: NONE
065394,000093:
065395,000094: # INPUT: E, EDOT
065396,000095: # TJP, TJV, TJU TJ MUST NOT BE NEGATIVE ZERO
065397,000096:
065398,000097: # OUTPUT: TJP, TJV, TJU
065399,000098:
065400,000099: 21,3646 BANK 21
065401,000100: 21,2000 SETLOC DAPS4
065402,000101: 21,2000 BANK
065403,000102:
065404,000103: 21,3646 COUNT* $$/DAPBU
065405,000104:
065406,000105: 21,3646 E6,1525 EBANK= TJU
065407,000106: 21,3646 00632 RATELIM2 OCT 00632 # 1.125 DEG/SEC
065408,000107: 21,3647 34736 POSTHRST CA HALF
065409,000108:
065410,000109: 21,3650 51505 NDX AXISCTR
065411,000110: 21,3651 55525 TS TJU
065412,000111: 21,3652 11745 CCS OLDSENSE
065413,000112: 21,3653 13673 TCF POSCHECK # JETS FIRING POSITIVELY
065414,000113: 21,3654 13676 TCF CTRCHECK # JETS OFF. CHECK INHIBITION CTR
065415,000114: 21,3655 51505 NEGCHECK INDEX AXISCTR # JETS FIRING NEGATIVELY
065416,000115: 21,3656 41525 CS TJU
065417,000116: 21,3657 10000 CCS A
065418,000117: 21,3660 00002 TC Q # RETURN
065419,000118: 21,3661 13663 TCF +2
065420,000119: 21,3662 13663 TCF +1 # JETS COMMANDED OFF. SET CTR AND RETURN
065421,000120: 21,3663 51505 SETCTR INDEX AXISCTR # JET FIRING REVERSAL COMMANDED. SET CTR,
065422,000121: 21,3664 33705 CA UTIME # SET JET TIME TO ZERO, AND RETURN
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Page 1509 |
065424,000123: 21,3665 51505 INDEX AXISCTR
065425,000124: 21,3666 55770 TS UJETCTR
065426,000125: 21,3667 34755 ZAPTJ CA ZERO
065427,000126: 21,3670 51505 INDEX AXISCTR
065428,000127: 21,3671 55525 TS TJU
065429,000128: 21,3672 00002 TC Q
065430,000129: 21,3673 51505 POSCHECK INDEX AXISCTR
065431,000130: 21,3674 31525 CA TJU
065432,000131: 21,3675 13657 TCF NEGCHECK +2
065433,000132: 21,3676 51505 CTRCHECK INDEX AXISCTR # CHECK JET INHIBITION COUNTER
065434,000133: 21,3677 11770 CCS UJETCTR
065435,000134: 21,3700 13702 TCF +2
065436,000135: 21,3701 00002 TC Q # CTR IS NOT POSITIVE. RETURN
065437,000136: 21,3702 13667 TCF ZAPTJ # CTR IS POSITIVE. INHIBIT FIRINGS
065438,000137: 21,3703 00002 TC Q # CTR IS NOT POSITIVE. RETURN
065439,000138: 21,3704 00004 OCT 00004
065440,000139: 21,3705 00012 UTIME OCT 00012
065441,000140: 21,3706 00012 OCT 00012
065442,000141: 21,3707 E6,1745 OLDSENSE EQUALS DAPTREG1
065443,000142: 21,3707 44753 NEGFIRE CS ONE # JETS FIRING NEGATIVELY
065444,000143: 21,3710 55745 TS OLDSENSE
065445,000144: 21,3711 31427 CA EDOT
065446,000145: 21,3712 13716 TCF +4
065447,000146: 21,3713 34753 PLUSFIRE CA ONE
065448,000147: 21,3714 55745 TS OLDSENSE
065449,000148: 21,3715 41427 CS EDOT # RATE DEAD BAND TEST
065450,000149: 21,3716 22000 LXCH A
065451,000150: 21,3717 40111 CS DAPBOOLS # IF DRIFTBIT = 1, USE ZERO TARGET RATE
065452,000151: 21,3720 74744 MASK DRIFTBIT # IF DRIFTBIT = 0, USE 0.10 RATE TARGET
065453,000152: 21,3721 10000 CCS A
065454,000153: 21,3722 34767 CA RATEDB1
065455,000154: 21,3723 60001 AD L
065456,000155: 21,3724 00006 EXTEND
065457,000156: 21,3725 63735 BZMF SPSSTART
065458,000157: 21,3726 13652 TCF POSTHRST +3
065459,000158:
065460,000159: 21,3727 51505 SPSRCS INDEX AXISCTR # JET SENSE TEST
065461,000160: 21,3730 11525 CCS TJU
065462,000161: 21,3731 13713 TCF PLUSFIRE # JETS FIRING POSITIVELY
065463,000162: 21,3732 13734 TCF +2
065464,000163: 21,3733 13707 TCF NEGFIRE # JETS FIRING NEGATIVELY
065465,000164: 21,3734 55745 TS OLDSENSE # JETS OFF
065466,000165: 21,3735 31427 SPSSTART CA EDOT # OUTER RATE LIMIT TEST
065467,000166: 21,3736 00006 EXTEND
065468,000167: 21,3737 74766 MP RATELIM1
065469,000168: 21,3740 10000 CCS A
065470,000169: 21,3741 13760 TCF NEGTHRST # OUTER RATE LIMIT EXCEEDED
065471,000170: 21,3742 13744 TCF +2
065472,000171: 21,3743 13647 TCF POSTHRST # OUTER RATE LIMIT EXCEEDED
065473,000172: 21,3744 31427 CA EDOT # COAST ZONE TEST
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Page 1510 |
065475,000174: 21,3745 61752 AD E
065476,000175: 21,3746 00006 EXTEND
065477,000176: 21,3747 71411 MP DKDB # PAD LOADED DEADBAND. FRESHSTART: 1.4 DEG
065478,000177: 21,3750 00006 EXTEND
065479,000178: 21,3751 13766 BZF TJZERO
065480,000179:
065481,000180: 21,3752 00006 EXTEND
065482,000181: 21,3753 63762 BZMF +7
065483,000182: 21,3754 31427 CA EDOT
065484,000183: 21,3755 63646 AD RATELIM2
065485,000184: 21,3756 00006 EXTEND
065486,000185: 21,3757 63766 BZMF TJZERO
065487,000186: 21,3760 44736 NEGTHRST CS HALF
065488,000187: 21,3761 13650 TCF POSTHRST +1
065489,000188: 21,3762 43646 +7 CS RATELIM2
065490,000189: 21,3763 61427 AD EDOT
065491,000190: 21,3764 00006 EXTEND
065492,000191: 21,3765 63647 BZMF POSTHRST
065493,000192: 21,3766 34755 TJZERO CA ZERO
065494,000193: 21,3767 13650 TCF POSTHRST +1
065495,000194:
065496,000195: 21,3770 4766 RATELIM1 = CALLCODE # = 00032, CORRESPONDING TO 1.73 DEG/SEC
065497,000196: 21,3770 4767 RATEDB1 = TBUILDFX # = 00045, CORRESPONDS TO 0.101 DEG/SEC
065498,000197:
End of include-file SPS_BACK-UP_RCS_CONTROL.agc. Parent file is MAIN.agc