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. |
008308,000002: ## Copyright: Public domain.
008309,000003: ## Filename: AGS_INITIALIZATION.agc
008310,000004: ## Purpose: Part of the source code for Luminary 1A build 099.
008311,000005: ## It is part of the source code for the Lunar Module's (LM)
008312,000006: ## Apollo Guidance Computer (AGC), for Apollo 11.
008313,000007: ## Assembler: yaYUL
008314,000008: ## Contact: Hartmuth Gutsche <hgutsche@xplornet.com>.
008315,000009: ## Website: www.ibiblio.org/apollo.
008316,000010: ## Pages: 206-210
008317,000011: ## Mod history: 2009-05-19 HG Transcribed from page images.
008318,000012: ## 2016-12-13 RSB Proofed text comments with octopus/ProoferComments
008319,000013: ## and corrected the errors found.
008320,000014: ## 2017-03-14 RSB Comment-text fixes identified in 5-way
008321,000015: ## side-by-side diff of Luminary 69/99/116/131/210.
008322,000016: ##
008323,000017: ## This source code has been transcribed or otherwise adapted from
008324,000018: ## digitized images of a hardcopy from the MIT Museum. The digitization
008325,000019: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
008326,000020: ## the Museum. Many thanks to both. The images (with suitable reduction
008327,000021: ## in storage size and consequent reduction in image quality as well) are
008328,000022: ## available online at www.ibiblio.org/apollo. If for some reason you
008329,000023: ## find that the images are illegible, contact me at info@sandroid.org
008330,000024: ## about getting access to the (much) higher-quality images which Paul
008331,000025: ## actually created.
008332,000026: ##
008333,000027: ## Notations on the hardcopy document read, in part:
008334,000028: ##
008335,000029: ## Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
008336,000030: ## 16:27 JULY 14, 1969
008337,000031:
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Page 206 |
008339,000033:
008340,000034: # PROGRAM NAME: AGS INITIALIZATION (R47)
008341,000035:
008342,000036: # WRITTEN BY: RHODE/KILROY/FOLLETT
008343,000037:
008344,000038: # MOD NO. : 0
008345,000039: # DATE: 23 MARCH 1967
008346,000040: # MOD BY: KILROY
008347,000041:
008348,000042: # MOD NO.: 1
008349,000043: # DATE: 28 OCTOBER 1967
008350,000044: # MOD BY: FOLLETT
008351,000045:
008352,000046: # FUNCT. DESC.: (1) TO PROVIDE THE AGS ABORT ELECTRONICS ASSEMBLY (AEA) WITH THE LEM AND CSM STATE VECTORS
008353,000047: # (POSITION,VELOCITY,TIME) IN LEM IMU COORDINATES BY MEANS OF THE LGC DIGITAL DOWNLINK.
008354,000048:
008355,000049: # (2) TO ZERO THE ICDU, LGC AND AEA GIMBAL ANGLE COUNTERS SIMULTANEOUSLY IN ORDER TO ESTABLISH A
008356,000050: # COMMON ZERO REFERENCE FOR THE MEASUREMENT OF GIMBAL (EULER) ANGLES WHICH DEFINE LEM ATTITUDE
008357,000051:
008358,000052: # (3) TO ESTABLISH THE GROUND ELAPSED TIME OF AEA CLOCK ZERO. (IF AN AEA CLOCK ZERO IS
008359,000053: # REQUESTED DURING THIS PROGRAM
008360,000054:
008361,000055: # LOG SECTION: AGS INITIALIZATION
008362,000056:
008363,000057: # CALLING SEQ: PROGRAM IS ENTERED WHEN ASTRONAUT KEYS V47E ON DSKY.
008364,000058: # R47 MAY BE CALLED AT ANY TIME EXCEPT WHEN ANOTHER EXTENDED VERB IS IN PROGRESS
008365,000059:
008366,000060: # SUBROUTINES
008367,000061: # CALLED:
008368,000062:
008369,000063: # NORMAL EXIT: ENDEXT
008370,000064:
008371,000065: # ALARM/ABORT: ALARM - BAD REFSMMAT - CODE:220
008372,000066: # OPERATOR ERROR IF V47 SELECTED DURING ANOTHER EXTENDED VERB.
008373,000067:
008374,000068: # ERASABLES
008375,000069: # USED: SAMPTIME (2) TIME OF :ENTER: KEYSTROKE
008376,000070: # AGSK (2) GROUND ELAPSED TIME OF THE AEA CLOCK :ZERO:
008377,000071: # AGSBUFF (140) CONTAINS AGS INITIALIZATION DATA (SEE :OUTPUT: BELOW)
008378,000072: # AGSWORD (1) PREVIOUS DOWNLIST SAVED HERE
008379,000073:
008380,000074: 05,2447 E4,1600 EBANK= AGSBUFF
008381,000075:
008382,000076: 40,2000 BANK 40
008383,000077: 32,2000 SETLOC R47
008384,000078: 32,2000 BANK
008385,000079:
008386,000080: 32,2005 COUNT* $$/R47
008387,000081:
008388,000082: 32,2005 34737 AGSINIT CAF REFSMBIT
008389,000083: 32,2006 70077 MASK FLAGWRD3 # CHECK REFSMFLG.
008390,000084: 32,2007 10000 CCS A
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008392,000086: 32,2010 02017 TC REDSPTEM # REFSMMAT IS OK
008393,000087: 32,2011 05567 TC ALARM # REFSMMAT IS BAD
008394,000088: 32,2012 00220 OCT 220
008395,000089: 32,2013 05472 TC ENDEXT
008396,000090:
008397,000091: 32,2014 00006 NEWAGS EXTEND
008398,000092: 32,2015 30014 DCA SAMPTIME # TIME OF THE :ENTER: KEYSTROKE
008399,000093: 32,2016 53421 DXCH AGSK # BECOMES NEW AEA CLOCK :ZERO:
008400,000094:
008401,000095: 32,2017 00006 REDSPTEM EXTEND
008402,000096: 32,2020 31421 DCA AGSK
008403,000097: 32,2021 53052 DXCH DSPTEMX
008404,000098: 32,2022 32172 AGSDISPK CAF V06N16
008405,000099: 32,2023 04616 TC BANKCALL # R1 = 00XXX. HRS., R2 = 000XX MIN.,
008406,000100: 32,2024 20334 CADR GOMARKF # R3 = 0XX.XX SEC.
008407,000101: 32,2025 05472 TC ENDEXT # TERMINATE RETURN
008408,000102: 32,2026 02036 TC AGSVCALC # PROCEED RETURN
008409,000103: 32,2027 44746 CS BIT6 # IS ENTER VIA A V32
008410,000104: 32,2030 60154 AD MPAC
008411,000105: 32,2031 00006 EXTEND
008412,000106: 32,2032 12014 BZF NEWAGS # YES, USE KEYSTROKE TIME FOR NEW AGSK
008413,000107:
008414,000108: 32,2033 00006 EXTEND # NO, NEW AGSK LOADED VIA V25
008415,000109: 32,2034 31052 DCA DSPTEMX # LOADED INTO DSPTEMX BY KEYING
008416,000110: 32,2035 02016 TC REDSPTEM -1 # V25E FOLLOWED BY HRS.,MINS.,SECS.
008417,000111: # DISPLAY THE NEW K
008418,000112:
008419,000113: 32,2036 06037 AGSVCALC TC INTPRET
008420,000114: 32,2037 77614 SET
008421,000115: 32,2040 01076 NODOFLAG # DONT ALLOW V37
008422,000116: 32,2041 77414 SET EXIT
008423,000117: 32,2042 02076 XDSPFLAG
008424,000118:
008425,000119: 32,2043 32172 CAF V06N16
008426,000120: 32,2044 04616 TC BANKCALL
008427,000121: 32,2045 20620 CADR EXDSPRET
008428,000122:
008429,000123: 32,2046 06037 TC INTPRET # EXTRAPOLATE LEM AND CSM STATE VECTORS
008430,000124: 32,2047 77634 RTB # TO THE PRESENT TIME
008431,000125: 32,2050 21573 LOADTIME # LOAD MPAC WITH TIME2,TIME1
008432,000126: 32,2051 34041 STCALL TDEC1 # CALCULATE LEM STATE VECTOR
008433,000127: 32,2052 27057 LEMPREC
008434,000128: 32,2053 77624 CALL # CALL ROUTINE TO CONVERT TO SM COORDS AND
008435,000129: 32,2054 64132 SCALEVEC # PROVIDE PROPER SCALING
008436,000130: 32,2055 16201 STODL AGSBUFF # (LEMPREC AND CSMPREC LEAVE TDEC1 IN TAT)
008437,000131: 32,2056 00015 TAT # TAT = TIME TO WHICH RATT1 AND VATT1 ARE
008438,000132: 32,2057 34041 STCALL TDEC1 # COMPUTED (CSEC SINCE CLOCK START B-28).
008439,000133: 32,2060 27043 CSMPREC # CALCULATE CSM STATE VECTOR FOR SAME TIME
008440,000134: 32,2061 77624 CALL
008441,000135: 32,2062 64132 SCALEVEC
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008443,000137: 32,2063 16207 STODL AGSBUFF +6
008444,000138: 32,2064 00015 TAT
008445,000139: 32,2065 56225 DSU DDV # CALCULATE AND STORE THE TIME
008446,000140: 32,2066 02021 AGSK
008447,000141: 32,2067 24175 TSCALE
008448,000142: 32,2070 02215 STORE AGSBUFF +12D
008449,000143: 32,2071 77776 EXIT
008450,000144:
008451,000145: 32,2072 34753 CAF LAGSLIST
008452,000146: 32,2073 54332 TS DNLSTCOD
008453,000147:
008454,000148: 32,2074 32176 CAF 20SEC # DELAY FOR 20 SEC WHILE THE AGS
008455,000149: 32,2075 04616 TC BANKCALL # DOWNLIST IS TRANSMITTED
008456,000150: 32,2076 01735 CADR DELAYJOB
008457,000151:
008458,000152: 32,2077 31324 CA AGSWORD
008459,000153: 32,2100 54332 TS DNLSTCOD # RETURN TO THE OLD DOWNLIST
008460,000154: 32,2101 34744 CAF IMUSEBIT
008461,000155: 32,2102 70074 MASK FLAGWRD0 # CHECK IMUSE FLAG.
008462,000156: 32,2103 10000 CCS A
008463,000157: 32,2104 02122 TC AGSEND # IMU IS BEING USED - DO NOT ZERO
008464,000158: 32,2105 11304 CKSTALL CCS IMUCADR # CHECK FOR IMU USAGE WHICH AVOIDS THE
008465,000159: 32,2106 12111 TCF +3 # IMUSE BIT: I.E., IMU COMPENSATION.
008466,000160: 32,2107 12115 TCF +6 # FREE. GO AHEAD WITH THE IMU ZERO.
008467,000161: 32,2110 12111 TCF +1
008468,000162: 32,2111 34363 +3 CAF TEN # WAIT .1 SEC AND TRY AGAIN.
008469,000163: 32,2112 04616 TC BANKCALL
008470,000164: 32,2113 01735 CADR DELAYJOB
008471,000165: 32,2114 12105 TCF CKSTALL
008472,000166:
008473,000167: 32,2115 04616 +6 TC BANKCALL # IMU IS NOT IN USE
008474,000168: 32,2116 16714 CADR IMUZERO # SET IMU ZERO DISCRETE FOR 320MSECS
008475,000169: 32,2117 04616 TC BANKCALL # WAIT 3 SEC FOR COUNTERS TO INCREMENT
008476,000170: 32,2120 17716 CADR IMUSTALL
008477,000171: 32,2121 02122 TC AGSEND
008478,000172: 32,2122 05516 AGSEND TC DOWNFLAG # ALLOW V37
008479,000173: 32,2123 00054 ADRES NODOFLAG
008480,000174:
008481,000175: 32,2124 32173 CAF V50N16
008482,000176: 32,2125 04616 TC BANKCALL
008483,000177: 32,2126 20342 CADR GOMARK3
008484,000178: 32,2127 15472 TCF ENDEXT
008485,000179: 32,2130 15472 TCF ENDEXT
008486,000180: 32,2131 05472 TC ENDEXT
008487,000181:
008488,000182: 32,2132 64375 SCALEVEC VLOAD MXV
008489,000183: 32,2133 00025 VATT1
008490,000184: 32,2134 01734 REFSMMAT
008491,000185: 32,2135 72561 VXSC VSL2
008492,000186: 32,2136 24202 VSCALE
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008494,000188: 32,2137 53255 VAD VAD # THIS SECTION ROUNDS THE VECTOR, AND
008495,000189: 32,2140 24204 AGSRND1 # CORRECTS FOR THE FACT THAT THE AGS
008496,000190: 32,2141 24212 AGSRND2 # IS A 2 S COMPLIMENT MACHINE WHILE THE
008497,000191: 32,2142 77634 RTB # LGC IS A 1 S COMPLIMENT MACHINE.
008498,000192: 32,2143 21772 VECSGNAG
008499,000193: 32,2144 24025 STOVL VATT1
008500,000194: 32,2145 00017 RATT1
008501,000195: 32,2146 74321 MXV VXSC
008502,000196: 32,2147 01734 REFSMMAT
008503,000197: 32,2150 24200 RSCALE
008504,000198: 32,2151 53212 VSL8 VAD # AGAIN THIS SECTION ROUNDS. TWO VECTORS
008505,000199: 32,2152 24204 AGSRND1 # ARE ADDED TO DEFEAT ALSIGNAG IN THE
008506,000200: 32,2153 47055 VAD RTB # CASE OF A HIGH-ORDER ZERO COUPLED WITH
008507,000201: 32,2154 24212 AGSRND2 # A LOW ORDER NEGATIVE PART.
008508,000202: 32,2155 21772 VECSGNAG
008509,000203: 32,2156 77750 LXA,1
008510,000204: 32,2157 00024 VATT1
008511,000205: 32,2160 72130 SXA,1 LXA,1
008512,000206: 32,2161 00155 MPAC +1
008513,000207: 32,2162 00026 VATT1 +2
008514,000208: 32,2163 72130 SXA,1 LXA,1
008515,000209: 32,2164 00160 MPAC +4
008516,000210: 32,2165 00030 VATT1 +4
008517,000211: 32,2166 43530 SXA,1 RVQ
008518,000212: 32,2167 00162 MPAC +6
008519,000213:
008520,000214: 32,2170 4753 LAGSLIST = ONE
008521,000215: 32,2170 00216 V01N14 VN 0114
008522,000216: 32,2171 14400 V50N00A VN 5000
008523,000217: 32,2172 6010 V00N25 EQUALS OCT31
008524,000218: 32,2172 01420 V06N16 VN 0616
008525,000219: 32,2173 4242 V00N34 EQUALS 34DEC
008526,000220: 32,2173 14420 V50N16 VN 5016
008527,000221: 32,2174 03100 00000 TSCALE 2DEC 100 B-10 # CSEC TO SEC SCALE FACTOR
008528,000222: 32,2176 03720 20SEC DEC 2000 B-14
008529,000223: 32,2177 15077 05041 RSCALE 2DEC 3.280839 B-3 # METERS TO FEET SCALE FACTOR
008530,000224: 32,2201 24402 25724 VSCALE 2DEC 3.280839 E2 B-9 # METERS/CS TO FEET/SEC SCALE FACTOR
008531,000225: 32,2203 00000 60000 AGSRND1 2OCT 0000060000
008532,000226: 32,2205 00000 60000 2OCT 0000060000
008533,000227: 32,2207 00000 60000 2OCT 0000060000
008534,000228: 32,2211 00000 37777 AGSRND2 2OCT 0000037777
008535,000229: 32,2213 00000 37777 2OCT 0000037777
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008537,000231: 32,2215 00000 37777 2OCT 0000037777
008538,000232:
008539,000233: 32,2217 30,2000 SBANK= LOWSUPER # FOR SUBSEQUENT LOW 2CADRS.
008540,000234:
End of include-file AGS_INITIALIZATION.agc. Parent file is MAIN.agc