Source Code
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This is a reconstruction of the AGC program Luminary 99 Rev 0. It was the third release
of the Lunar Module flight software targeted for use in Apollo 11, after Luminary 96 and 97.
A bug (which had been around since at least Apollo 10, Luminary 69) was
discovered in Rev 0 shortly before the Apollo 11 flight, resulting in a last minute
revision into Rev 1,
which is what actually flew rather than
the Rev 0 presented here. A hardcopy of Rev 0 is known to
exist — it belonged to AGC developer Allan Klumpp for many years — but
unfortunately the Virtual AGC Project has not had access to that hardcopy. Thus
the code you see here had been reconstructed (we believe accurately) rather than
transcribed. The first step of the reconstruction of the Rev 0 source code was
the transcription of the Rev 1 source code from a hardcopy in the MIT Museum collection.
The process of reverting the active portion of the source code (i.e., other than
program comments) from Rev 1 to Rev 0 was very minor, consisting
only of moving the position of the STARTSB1 label in
FRESH START AND RESTART. Allan had previously given
us the checksums of the memory banks of Rev 0, and we have verified the program presented here has checksums
identical to all banks of Allan's listing of Rev 0. The notations on Allan's Rev 0 program listing read,
in part:GAP: ASSEMBLE REVISION 099 OF AGC PROGRAM LUMINARY BY NASA 2021112-051 A single program comment is known to differ between Rev 0 and Rev 1, but these are harder to reconstruct and verify than changes to the active portion of the code. Thus it is possible that there are additional differences between the program comments in Rev 0 and Rev 1 that are unknown to us, and therefore are not reflected in the code presented here. |
014332,000002: ## Copyright: Public domain.
014333,000003: ## Filename: R63.agc
014334,000004: ## Purpose: Part of the reconstructed source code for LMY99 Rev 0,
014335,000005: ## otherwise known as Luminary Rev 99, the third release
014336,000006: ## of the Apollo Guidance Computer (AGC) software for Apollo 11.
014337,000007: ## It differs from LMY99 Rev 1 (the flown version) only in the
014338,000008: ## placement of a single label. The corrections shown here have
014339,000009: ## been verified to have the same bank checksums as AGC developer
014340,000010: ## Allan Klumpp's copy of Luminary Rev 99, and so are believed
014341,000011: ## to be accurate. This file is intended to be a faithful
014342,000012: ## recreation, except that the code format has been changed to
014343,000013: ## conform to the requirements of the yaYUL assembler rather than
014344,000014: ## the original YUL assembler.
014345,000015: ##
014346,000016: ## Assembler: yaYUL
014347,000017: ## Contact: Ron Burkey <info@sandroid.org>.
014348,000018: ## Website: www.ibiblio.org/apollo.
014349,000019: ## Pages: 338-341
014350,000020: ## Mod history: 2009-05-16 RSB Adapted from the corresponding
014351,000021: ## Luminary131 file, using page
014352,000022: ## images from Luminary 1A.
014353,000023: ## 2016-12-14 RSB Proofed text comments with octopus/ProoferComments
014354,000024: ## and corrected the errors found.
014355,000025: ## 2017-01-26 RSB Back-ported a comment-text fix from Luminary 69.
014356,000026: ## 2017-03-07 RSB Comment-text fixes noted in proofing Luminary 116.
014357,000027: ## 2017-08-01 MAS Created from LMY99 Rev 1.
014358,000028:
014359,000029: ## This source code has been transcribed or otherwise adapted from
014360,000030: ## digitized images of a hardcopy from the MIT Museum. The digitization
014361,000031: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
014362,000032: ## the Museum. Many thanks to both. The images (with suitable reduction
014363,000033: ## in storage size and consequent reduction in image quality as well) are
014364,000034: ## available online at www.ibiblio.org/apollo. If for some reason you
014365,000035: ## find that the images are illegible, contact me at info@sandroid.org
014366,000036: ## about getting access to the (much) higher-quality images which Paul
014367,000037: ## actually created.
014368,000038: ##
014369,000039: ## The code has been modified to match LMY99 Revision 0, otherwise
014370,000040: ## known as Luminary Revision 99, the Apollo 11 software release preceeding
014371,000041: ## the listing from which it was transcribed. It has been verified to
014372,000042: ## contain the same bank checksums as AGC developer Allan Klumpp's listing
014373,000043: ## of Luminary Revision 99 (for which we do not have scans).
014374,000044: ##
014375,000045: ## Notations on Allan Klumpp's listing read, in part:
014376,000046: ##
014377,000047: ## ASSEMBLE REVISION 099 OF AGC PROGRAM LUMINARY BY NASA 2021112-51
014378,000048:
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Page 338 |
014380,000050: # SUBROUTINE NAME: V89CALL
014381,000051: # MOD NO: 0 DATE: 9 JAN 1968
014382,000052: # MOD BY: DIGITAL DEVEL GROUP LOG SECTION: R63
014383,000053:
014384,000054: # FUNCTIONAL DESCRIPTION:
014385,000055:
014386,000056: # CALLED BY VERB 89 ENTER DURING P00. PRIO 10 USED. CALCULATES AND
014387,000057: # DISPLAYS FINAL FDAI BALL ANGLES TO POINT LM +X OR +Z AXIS AT CSM.
014388,000058:
014389,000059: # 1. KEY IN V 89 E ONLY IF IN PROG 00. IF NOT IN P00, OPERATOR ERROR AND
014390,000060: # EXIT R63, OTHERWISE CONTINUE.
014391,000061:
014392,000062: # 2. IF IN P00, DO IMU STATUS CHECK ROUTINE (R02BOTH). IF IMU ON AND ITS
014393,000063: # ORIENTATION KNOWN TO LGC, CONTINUE.
014394,000064:
014395,000065: # 3. FLASH DISPLAY V 04 N 06. R2 INDICATES WHICH SPACECRAFT AXIS IS TO
014396,000066: # BE POINTED AT CSM. INITIAL CHOICE IS PREFERRED (+Z) AXIS (R2=1).
014397,000067: # ASTRONAUT CAN CHANGE TO (+X) AXIS (R2 NOT =1) BY V 22 E 2 E. CONTINUE
014398,000068: # AFTER KEYING IN PROCEED.
014399,000069:
014400,000070: # 4. BOTH VEHICLE STATE VECTORS UPDATED BY CONIC EQS.
014401,000071:
014402,000072: # 5. HALF MAGNITUDE UNIT LOS VECTOR (IN STABLE MEMBER COORDINATES) AND
014403,000073: # HALF MAGNITUDE UNIT SPACECRAFT AXIS VECTOR (IN BODY COORDINATES)
014404,000074: # PREPARED FOR VECPOINT.
014405,000075:
014406,000076: # 6. GIMBAL ANGLES FROM VECPOINT TRANSFORMED INTO FDAI BALL ANGLES BY
014407,000077: # BALLANGS. FLASH DISPLAY V 06 N 18 AND AWAIT RESPONSE.
014408,000078:
014409,000079: # 7. RECYCLE - RETURN TO STEP 4.
014410,000080: # TERMINATE - EXIT R63.
014411,000081: # PROCEED - RESET 3AXISFLG AND CALL R60LEM FOR ATTITUDE MANEUVER.
014412,000082:
014413,000083: # CALLING SEQUENCE: V 89 E.
014414,000084:
014415,000085: # SUBROUTINES CALLED: CHKPOOH, R02BOTH, GOXDSPF, CSMCONIC, LEMCONIC,
014416,000086: # VECPOINT, BALLANGS, R60LEM.
014417,000087:
014418,000088: # NORMAL EXIT MODES: TC ENDEXT
014419,000089:
014420,000090: # ALARMS: 1. OPERATOR ERROR IF NOT IN P00.
014421,000091: # 2. PROGRAM ALARM IF IMU IS OFF.
014422,000092: # 3. PROGRAM ALARM IF IMU ORIENTATION IS UNKNOWN.
014423,000093:
014424,000094: # OUTPUT: NONE
014425,000095:
014426,000096: # ERASABLE INITIALIZATION REQUIRED: NONE
014427,000097:
014428,000098: # DEBRIS: OPTION1, +1, TDEC1, POINTVSM, SCAXIS, CPHI, CTHETA, CPSI,
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Page 339 |
014430,000100: # 3AXISFLG.
014431,000101:
014432,000102: 06,3715 E4,1606 EBANK= RONE
014433,000103: 32,2217 BANK 32
014434,000104: 26,2000 SETLOC BAWLANGS
014435,000105: 26,2000 BANK
014436,000106:
014437,000107: 26,2022 COUNT* $$/R63
014438,000108: 26,2022 04616 V89CALL TC BANKCALL # IMU STATUS CHECK. RETURNS IF ORIENTATION
014439,000109: 26,2023 11254 CADR R02BOTH # KNOWN. ALARMS IF NOT.
014440,000110: 26,2024 36245 CAF THREE # ALLOW ASTRONAUT TO SELECT DESIRED
014441,000111: 26,2025 55051 TS OPTIONX # TRACKING ATTITUDE AXIS.
014442,000112: 26,2026 34753 CAF ONE
014443,000113: 26,2027 55052 TS OPTIONX +1
014444,000114: 26,2030 32117 CAF VB04N12 # V 04 N 12
014445,000115: 26,2031 04616 TC BANKCALL
014446,000116: 26,2032 20476 CADR GOFLASH
014447,000117: 26,2033 05472 TC ENDEXT # TERMINATE
014448,000118: 26,2034 02036 TC +2 # PROCEED
014449,000119: 26,2035 02030 TC -5 # DATA IN. OPTION1+1 = 1 FOR Z AXIS
014450,000120: 26,2036 06037 V89RECL TC INTPRET # = 2 FOR X AXIS
014451,000121: 26,2037 43234 RTB DAD
014452,000122: 26,2040 21573 LOADTIME # READ PRESENT TIME
014453,000123: 26,2041 14122 DP1MIN
014454,000124: 26,2042 02205 STORE TSTART82 # SAVE TIME FOR LEMCONIC CALL
014455,000125: 26,2043 34041 STCALL TDEC1 # STORE TIME FOR CSMCONIC CALL
014456,000126: 26,2044 27066 CSMCONIC # CSM STATE VECTOR UPDATE
014457,000127: 26,2045 77775 VLOAD # CSMCONIC LEFT R VECTOR IN RATT
014458,000128: 26,2046 00001 RATT
014459,000129: 26,2047 16207 STODL RONE # SAVE FOR LINE OF SIGHT (LOS) COMPUTATION
014460,000130: 26,2050 02205 TSTART82
014461,000131: 26,2051 34041 STCALL TDEC1 # STORE TIME FOR LEMCONIC CALL
014462,000132: 26,2052 27100 LEMCONIC # LEM STATE VECTOR UPDATE
014463,000133: 26,2053 52375 VLOAD VSU # CSM POSITION - LEM POSITION = LOS
014464,000134: 26,2054 02207 RONE # LOS VECTOR LEFT IN MPAC
014465,000135: 26,2055 00001 RATT
014466,000136: 26,2056 47121 MXV RTB # (REFSMMAT X LOS). TRANSFORMS LOS FROM
014467,000137: 26,2057 01734 REFSMMAT # REFERENCE COORD TO STAB MEMB COORD.
014468,000138: 26,2060 21726 NORMUNIT
014469,000139: 26,2061 03773 STORE POINTVSM # STORE LOS FOR VECPOINT CALL
014470,000140: 26,2062 77776 EXIT
014471,000141: 26,2063 41052 CS OPTIONX +1 # 1 FOR Z AXIS. 2 FOR X AXIS.
014472,000142: 26,2064 64753 AD ONE
014473,000143: 26,2065 00006 EXTEND
014474,000144: 26,2066 12113 BZF ALINEZ
014475,000145: 26,2067 06037 ALINEX TC INTPRET # X AXIS ALIGNMENT
014476,000146: 26,2070 77775 VLOAD
014477,000147: 26,2071 06520 UNITX # READ (.5, 0, 0)
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014479,000149: 26,2072 37765 V89CALL1 STCALL SCAXIS # STORE SELECTED ALIGNMENT AXIS
014480,000150: 26,2073 56040 VECPOINT # PUTS DESIRED GIM ANG (OG,IG,MG) IN TMPAC
014481,000151: 26,2074 00322 STORE CPHI # STORE GIMBAL ANGLES FOR BALLANGS CALL.
014482,000152: 26,2075 77776 EXIT
014483,000153: 26,2076 04616 TC BANKCALL
014484,000154: 26,2077 54266 CADR BALLANGS # PUTS DESIRED BALL ANGLES IN FDAIX,Y,Z
014485,000155: 26,2100 32120 CAF VB06N18 # V 06 N 18
014486,000156: 26,2101 04616 TC BANKCALL # NOUN 18 REFERS TO FDAIX,Y,Z
014487,000157: 26,2102 20476 CADR GOFLASH
014488,000158: 26,2103 05472 TC ENDEXT # TERMINATE
014489,000159: 26,2104 02106 TC +2 # PROCEED
014490,000160: 26,2105 02036 TC V89RECL # RECYCLE
014491,000161: 26,2106 05516 TC DOWNFLAG # RESET 3 AXIS FLAG
014492,000162: 26,2107 00124 ADRES 3AXISFLG # RESET BIT6 FLAG WORD 5
014493,000163: 26,2110 04616 TC BANKCALL # PERFORMS LEM MANEUVER TO ALIGN SELECTED
014494,000164: 26,2111 54123 CADR R60LEM # SPACECRAFT AXIS TO CSM.
014495,000165: 26,2112 15472 TCF ENDEXT # TERMINATE R63
014496,000166:
014497,000167: 26,2113 06037 ALINEZ TC INTPRET # Z AXIS ALIGNMENT
014498,000168: 26,2114 52175 VLOAD GOTO
014499,000169: 26,2115 06514 UNITZ # READ (0, 0, .5)
014500,000170: 26,2116 54072 V89CALL1
014501,000171:
014502,000172: 26,2117 01014 VB04N12 VN 412
014503,000173: 26,2120 01422 VB06N18 VN 0618
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014505,000175: 26,2121 00000 13560 DP1MIN 2DEC 6000 B-28
014506,000176:
End of include-file R63.agc. Parent file is MAIN.agc