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. |
014089,000002: ## Copyright: Public domain.
014090,000003: ## Filename: R63.agc
014091,000004: ## Purpose: A section of Luminary revision 116.
014092,000005: ## It is part of the source code for the Lunar Module's (LM)
014093,000006: ## Apollo Guidance Computer (AGC) for Apollo 12.
014094,000007: ## This file is intended to be a faithful transcription, except
014095,000008: ## that the code format has been changed to conform to the
014096,000009: ## requirements of the yaYUL assembler rather than the
014097,000010: ## original YUL assembler.
014098,000011: ## Reference: pp. 339-342
014099,000012: ## Assembler: yaYUL
014100,000013: ## Contact: Ron Burkey <info@sandroid.org>.
014101,000014: ## Website: www.ibiblio.org/apollo/index.html
014102,000015: ## Mod history: 2017-01-22 MAS Created from Luminary 99.
014103,000016: ## 2017-01-26 RSB Back-ported a comment-text fix from Luminary 69.
014104,000017: ## Mod history: 2017-01-22 MAS Created from Luminary 99.
014105,000018: ## 2017-03-07 RSB Transcribed, and then proofed comment-text using
014106,000019: ## 3-way diff vs Luminary 99 and Luminary 131.
014107,000020: ## (Admittedly, the former is more for detecting errors
014108,000021: ## in Luminary 99 than the other way around.)
014109,000022:
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Page 339 |
014111,000024: # SUBROUTINE NAME: V89CALL
014112,000025: # MOD NO: 0 DATE: 9 JAN 1968
014113,000026: # MOD BY: DIGITAL DEVEL GROUP LOG SECTION: R63
014114,000027:
014115,000028: # FUNCTIONAL DESCRIPTION:
014116,000029:
014117,000030: # CALLED BY VERB 89 ENTER DURING P00. PRIO 10 USED. CALCULATES AND
014118,000031: # DISPLAYS FINAL FDAI BALL ANGLES TO POINT LM +X OR +Z AXIS AT CSM.
014119,000032:
014120,000033: # 1. KEY IN V 89 E ONLY IF IN PROG 00. IF NOT IN P00, OPERATOR ERROR AND
014121,000034: # EXIT R63, OTHERWISE CONTINUE.
014122,000035:
014123,000036: # 2. IF IN P00, DO IMU STATUS CHECK ROUTINE (R02BOTH). IF IMU ON AND ITS
014124,000037: # ORIENTATION KNOWN TO LGC, CONTINUE.
014125,000038:
014126,000039: # 3. FLASH DISPLAY V 04 N 06. R2 INDICATES WHICH SPACECRAFT AXIS IS TO
014127,000040: # BE POINTED AT CSM. INITIAL CHOICE IS PREFERRED (+Z) AXIS (R2=1).
014128,000041: # ASTRONAUT CAN CHANGE TO (+X) AXIS (R2 NOT =1) BY V 22 E 2 E. CONTINUE
014129,000042: # AFTER KEYING IN PROCEED.
014130,000043:
014131,000044: # 4. BOTH VEHICLE STATE VECTORS UPDATED BY CONIC EQS.
014132,000045:
014133,000046: # 5. HALF MAGNITUDE UNIT LOS VECTOR (IN STABLE MEMBER COORDINATES) AND
014134,000047: # HALF MAGNITUDE UNIT SPACECRAFT AXIS VECTOR (IN BODY COORDINATES)
014135,000048: # PREPARED FOR VECPOINT.
014136,000049:
014137,000050: # 6. GIMBAL ANGLES FROM VECPOINT TRANSFORMED INTO FDAI BALL ANGLES BY
014138,000051: # BALLANGS. FLASH DISPLAY V 06 N 18 AND AWAIT RESPONSE.
014139,000052:
014140,000053: # 7. RECYCLE - RETURN TO STEP 4.
014141,000054: # TERMINATE - EXIT R63.
014142,000055: # PROCEED - RESET 3AXISFLG AND CALL R60LEM FOR ATTITUDE MANEUVER.
014143,000056:
014144,000057: # CALLING SEQUENCE: V 89 E.
014145,000058:
014146,000059: # SUBROUTINES CALLED: CHKPOOH, R02BOTH, GOXDSPF, CSMCONIC, LEMCONIC,
014147,000060: # VECPOINT, BALLANGS, R60LEM.
014148,000061:
014149,000062: # NORMAL EXIT MODES: TC ENDEXT
014150,000063:
014151,000064: # ALARMS: 1. OPERATOR ERROR IF NOT IN P00.
014152,000065: # 2. PROGRAM ALARM IF IMU IS OFF.
014153,000066: # 3. PROGRAM ALARM IF IMU ORIENTATION IS UNKNOWN.
014154,000067:
014155,000068: # OUTPUT: NONE
014156,000069:
014157,000070: # ERASABLE INITIALIZATION REQUIRED: NONE
014158,000071:
014159,000072: # DEBRIS: OPTION1, +1, TDEC1, POINTVSM, SCAXIS, CPHI, CTHETA, CPSI,
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Page 340 |
014161,000074: # 3AXISFLG.
014162,000075:
014163,000076: 06,3723 E4,1606 EBANK= RONE
014164,000077: 32,2217 BANK 32
014165,000078: 26,2000 SETLOC BAWLANGS
014166,000079: 26,2000 BANK
014167,000080:
014168,000081: 26,2022 COUNT* $$/R63
014169,000082: 26,2022 04616 V89CALL TC BANKCALL # IMU STATUS CHECK. RETURNS IF ORIENTATION
014170,000083: 26,2023 11236 CADR R02BOTH # KNOWN. ALARMS IF NOT.
014171,000084: 26,2024 36250 CAF THREE # ALLOW ASTRONAUT TO SELECT DESIRED
014172,000085: 26,2025 55050 TS OPTIONX # TRACKING ATTITUDE AXIS.
014173,000086: 26,2026 34753 CAF ONE
014174,000087: 26,2027 55051 TS OPTIONX +1
014175,000088: 26,2030 32117 CAF VB04N12 # V 04 N 12
014176,000089: 26,2031 04616 TC BANKCALL
014177,000090: 26,2032 20477 CADR GOFLASH
014178,000091: 26,2033 05472 TC ENDEXT # TERMINATE
014179,000092: 26,2034 02036 TC +2 # PROCEED
014180,000093: 26,2035 02030 TC -5 # DATA IN. OPTION1+1 = 1 FOR Z AXIS
014181,000094: 26,2036 06042 V89RECL TC INTPRET # = 2 FOR X AXIS
014182,000095: 26,2037 43234 RTB DAD
014183,000096: 26,2040 21574 LOADTIME # READ PRESENT TIME
014184,000097: 26,2041 14122 DP1MIN
014185,000098: 26,2042 02205 STORE TSTART82 # SAVE TIME FOR LEMCONIC CALL
014186,000099: 26,2043 34041 STCALL TDEC1 # STORE TIME FOR CSMCONIC CALL
014187,000100: 26,2044 27067 CSMCONIC # CSM STATE VECTOR UPDATE
014188,000101: 26,2045 77775 VLOAD # CSMCONIC LEFT R VECTOR IN RATT
014189,000102: 26,2046 00001 RATT
014190,000103: 26,2047 16207 STODL RONE # SAVE FOR LINE OF SIGHT (LOS) COMPUTATION
014191,000104: 26,2050 02205 TSTART82
014192,000105: 26,2051 34041 STCALL TDEC1 # STORE TIME FOR LEMCONIC CALL
014193,000106: 26,2052 27101 LEMCONIC # LEM STATE VECTOR UPDATE
014194,000107: 26,2053 52375 VLOAD VSU # CSM POSITION - LEM POSITION = LOS
014195,000108: 26,2054 02207 RONE # LOS VECTOR LEFT IN MPAC
014196,000109: 26,2055 00001 RATT
014197,000110: 26,2056 47121 MXV RTB # (REFSMMAT X LOS). TRANSFORMS LOS FROM
014198,000111: 26,2057 01734 REFSMMAT # REFERENCE COORD TO STAB MEMB COORD.
014199,000112: 26,2060 21727 NORMUNIT
014200,000113: 26,2061 03773 STORE POINTVSM # STORE LOS FOR VECPOINT CALL
014201,000114: 26,2062 77776 EXIT
014202,000115: 26,2063 41051 CS OPTIONX +1 # 1 FOR Z AXIS. 2 FOR X AXIS.
014203,000116: 26,2064 64753 AD ONE
014204,000117: 26,2065 00006 EXTEND
014205,000118: 26,2066 12113 BZF ALINEZ
014206,000119: 26,2067 06042 ALINEX TC INTPRET # X AXIS ALIGNMENT
014207,000120: 26,2070 77775 VLOAD
014208,000121: 26,2071 06522 UNITX # READ (.5, 0, 0)
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014210,000123: 26,2072 37765 V89CALL1 STCALL SCAXIS # STORE SELECTED ALIGNMENT AXIS
014211,000124: 26,2073 56040 VECPOINT # PUTS DESIRED GIM ANG (OG,IG,MG) IN TMPAC
014212,000125: 26,2074 00322 STORE CPHI # STORE GIMBAL ANGLES FOR BALLANGS CALL.
014213,000126: 26,2075 77776 EXIT
014214,000127: 26,2076 04616 TC BANKCALL
014215,000128: 26,2077 54272 CADR BALLANGS # PUTS DESIRED BALL ANGLES IN FDAIX,Y,Z
014216,000129: 26,2100 32120 CAF VB06N18 # V 06 N 18
014217,000130: 26,2101 04616 TC BANKCALL # NOUN 18 REFERS TO FDAIX,Y,Z
014218,000131: 26,2102 20477 CADR GOFLASH
014219,000132: 26,2103 05472 TC ENDEXT # TERMINATE
014220,000133: 26,2104 02106 TC +2 # PROCEED
014221,000134: 26,2105 02036 TC V89RECL # RECYCLE
014222,000135: 26,2106 05516 TC DOWNFLAG # RESET 3 AXIS FLAG
014223,000136: 26,2107 00124 ADRES 3AXISFLG # RESET BIT6 FLAG WORD 5
014224,000137: 26,2110 04616 TC BANKCALL # PERFORMS LEM MANEUVER TO ALIGN SELECTED
014225,000138: 26,2111 54123 CADR R60LEM # SPACECRAFT AXIS TO CSM.
014226,000139: 26,2112 15472 TCF ENDEXT # TERMINATE R63
014227,000140:
014228,000141: 26,2113 06042 ALINEZ TC INTPRET # Z AXIS ALIGNMENT
014229,000142: 26,2114 52175 VLOAD GOTO
014230,000143: 26,2115 06516 UNITZ # READ (0, 0, .5)
014231,000144: 26,2116 54072 V89CALL1
014232,000145:
014233,000146: 26,2117 01014 VB04N12 VN 412
014234,000147: 26,2120 01422 VB06N18 VN 0618
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Page 342 |
014236,000149: 26,2121 00000 13560 DP1MIN 2DEC 6000 B-28
014237,000150:
End of include-file R63.agc. Parent file is MAIN.agc