Source Code

008302,000001: # Copyright: Public domain. 008303,000002: # Filename: AGS_INITIALIZATION.agc 008304,000003: # Purpose: Part of the source code for Luminary 1A build 099. 008305,000004: # It is part of the source code for the Lunar Module's (LM) 008306,000005: # Apollo Guidance Computer (AGC), for Apollo 11. 008307,000006: # Assembler: yaYUL 008308,000007: # Contact: Hartmuth Gutsche <hgutsche@xplornet.com>. 008309,000008: # Website: www.ibiblio.org/apollo. 008310,000009: # Pages: 206-210 008311,000010: # Mod history: 2009-05-19 HG Transcribed from page images. 008312,000011: 008313,000012: # This source code has been transcribed or otherwise adapted from 008314,000013: # digitized images of a hardcopy from the MIT Museum. The digitization 008315,000014: # was performed by Paul Fjeld, and arranged for by Deborah Douglas of 008316,000015: # the Museum. Many thanks to both. The images (with suitable reduction 008317,000016: # in storage size and consequent reduction in image quality as well) are 008318,000017: # available online at www.ibiblio.org/apollo. If for some reason you 008319,000018: # find that the images are illegible, contact me at info@sandroid.org 008320,000019: # about getting access to the (much) higher-quality images which Paul 008321,000020: # actually created. 008322,000021: 008323,000022: # Notations on the hardcopy document read, in part: 008324,000023: 008325,000024: # Assemble revision 001 of AGC program LMY99 by NASA 2021112-61 008326,000025: # 16:27 JULY 14, 1969 008327,000026: 008328,000027: # Page 206 008329,000028: 008330,000029: # PROGRAM NAME: AGS INITIALIZIZATION (R47) 008331,000030: 008332,000031: # WRITTEN BY: RHODE/KILROY/FOLLETT 008333,000032: 008334,000033: # MOD NO.: 0 008335,000034: # DATE: 23 MARCH 1967 008336,000035: # MOD BY: KILROY 008337,000036: 008338,000037: # MOD NO.: 1 008339,000038: # DATE: 28 OCTOBER 1967 008340,000039: # MOD BY: FOLLETT 008341,000040: 008342,000041: # FUNCT. DESC.: (1) TO PROVIDE THE AGS ABORT ELECTRONICS ASSEMBLY (AEA) WITH THE LEM AND CSM STATE VECTORS 008343,000042: # (POSITION,VELOCITY,TIME) IN LEM IMU COORDINATES BY MEANS OF THE LGC DIGITAL DOWNLINK. 008344,000043: 008345,000044: # (2) TO ZERO THE ICDU, LGC, AND AEA GIMBAL ANGLE COUNTER SIMULTANEOUSLY IN ORDER TO ESTABLISH A 008346,000045: # COMMON ZERO REFERENCE FOR THE MEASUREMENT OF GIMBAL (EULER) ANGLES WHICH DEFINE LEM ATTITUDE 008347,000046: 008348,000047: # (3) TO ESTABLISH THE GROUND ELAPSED TIME OF AEA CLOCK ZERO. (IF AN AEA CLOCK ZERO IS 008349,000048: # REQUESTED DURING THIS PROGRAM 008350,000049: 008351,000050: # LOG SECTION: AGS INITIALIZATION 008352,000051: 008353,000052: # CALLING SEQ: PROGRAM IS ENTERED WHEN ASTRONAUT KEYS V47E ON DSKY. 008354,000053: # R47 MAY BE CALLED AT ANY TIME EXCEPT WHEN ANOTHER EXTENDED VERB IS IN PROGRESS 008355,000054: 008356,000055: # SUBROUTINES 008357,000056: # CALLED: 008358,000057: 008359,000058: # NORMAL EXIT: ENDEXT 008360,000059: 008361,000060: # ALARM/ABORT: ALARM -- BAD REFSMMAT -- CODE:220 008362,000061: # OPERATOR ERROR IF V47 SELECTED DURING ANOTHER EXTENDED VERB. 008363,000062: 008364,000063: # ERASABLES 008365,000064: # USED: SAMPTIME (2) TIME OF :ENTER: KEYSTROKE 008366,000065: # AGSK (2) GROUND ELAPSED TIME OF THE AEA CLOCK :ZERO: 008367,000066: # AGSBUFF (140) CONTAINS AGS INITIALIZATION DATA (SEE :OUTPUT: BELOW) 008368,000067: # AGSWORD (1) PREVIOUS DOWNLIST SAVED HERE 008369,000068: 008370,000069: 05,2447 E4,1600 EBANK= AGSBUFF 008371,000070: 008372,000071: 40,2000 BANK 40 008373,000072: 32,2000 SETLOC R47 008374,000073: 32,2000 BANK 008375,000074: 008376,000075: 32,2005 COUNT* $$/R47 008377,000076: 008378,000077: 32,2005 34737 AGSINIT CAF REFSMBIT 008379,000078: 32,2006 70077 MASK FLAGWRD3 # CHECK REFSMFLG. 008380,000079: 32,2007 10000 CCS A 008381,000080: # Page 207 008382,000081: 32,2010 02017 TC REDSPTEM # REFSMMAT IS OK 008383,000082: 32,2011 05567 TC ALARM # REFSMMAT IS BAD 008384,000083: 32,2012 00220 OCT 220 008385,000084: 32,2013 05472 TC ENDEXT 008386,000085: 008387,000086: 32,2014 00006 NEWAGS EXTEND 008388,000087: 32,2015 30014 DCA SAMPTIME # TIME OF THE :ENTER: KEYSTROKE 008389,000088: 32,2016 53421 DXCH AGSK # BECOMES NEW AEA CLOCK :ZERO: 008390,000089: 008391,000090: 32,2017 00006 REDSPTEM EXTEND 008392,000091: 32,2020 31421 DCA AGSK 008393,000092: 32,2021 53052 DXCH DSPTEMX 008394,000093: 32,2022 32172 AGSDISPK CAF V06N16 008395,000094: 32,2023 04616 TC BANKCALL # R1 = 00XXX. HRS., R2 = 000XX MIN., 008396,000095: 32,2024 20334 CADR GOMARKF # R3 = 0XX.XX SEC. 008397,000096: 32,2025 05472 TC ENDEXT # TERMINATE RETURN 008398,000097: 32,2026 02036 TC AGSVCALC # PROCEED RETURN 008399,000098: 32,2027 44746 CS BIT6 # IS ENTER VIA A V32 008400,000099: 32,2030 60154 AD MPAC 008401,000100: 32,2031 00006 EXTEND 008402,000101: 32,2032 12014 BZF NEWAGS # YES, USE KEYSTROKE TIME FOR NEW AGSK 008403,000102: 008404,000103: 32,2033 00006 EXTEND # NO, NEW AGSK LOADED VIA V25 008405,000104: 32,2034 31052 DCA DSPTEMX # LOADED INTO DSPTEMX BY KEYING 008406,000105: 32,2035 02016 TC REDSPTEM -1 # V25E FOLLOWED BY HRS.,MINS.,SECS. 008407,000106: # DISPLAY THE NEW K. 008408,000107: 008409,000108: 32,2036 06037 AGSVCALC TC INTPRET 008410,000109: 32,2037 77614 SET 008411,000110: 32,2040 01076 NODOFLAG # DON'T ALLOW V37 008412,000111: 32,2041 77414 SET EXIT 008413,000112: 32,2042 02076 XDSPFLAG 008414,000113: 008415,000114: 32,2043 32172 CAF V06N16 008416,000115: 32,2044 04616 TC BANKCALL 008417,000116: 32,2045 20620 CADR EXDSPRET 008418,000117: 008419,000118: 32,2046 06037 TC INTPRET # EXTRAPOLATE LEM AND CSM STATE VECTORS 008420,000119: 32,2047 77634 RTB # TO THE PRESENT TIME 008421,000120: 32,2050 21573 LOADTIME # LOAD MPAC WITH TIME2,TIME1 008422,000121: 32,2051 34041 STCALL TDEC1 # CALCULATE LEM STATE VECTOR 008423,000122: 32,2052 27057 LEMPREC 008424,000123: 32,2053 77624 CALL # CALL ROUTINE TO CONVERT TO SM COORDS AND 008425,000124: 32,2054 64132 SCALEVEC # PROVIDE PROPER SCALING 008426,000125: 32,2055 16201 STODL AGSBUFF # (LEMPREC AND CSMPREC LEAVE TDEC1 IN TAT) 008427,000126: 32,2056 00015 TAT # TAT = TIME TO WHICH RATT1 AND VATT1 ARE 008428,000127: 32,2057 34041 STCALL TDEC1 # COMPUTED (CSEC SINCE CLOCK START B-28). 008429,000128: 32,2060 27043 CSMPREC # CALCULATE CSM STATE VECTOR FOR SAME TIME 008430,000129: 32,2061 77624 CALL 008431,000130: 32,2062 64132 SCALEVEC 008432,000131: # Page 208 008433,000132: 32,2063 16207 STODL AGSBUFF +6 008434,000133: 32,2064 00015 TAT 008435,000134: 32,2065 56225 DSU DDV # CALCULATE AND STORE THE TIME 008436,000135: 32,2066 02021 AGSK 008437,000136: 32,2067 24175 TSCALE 008438,000137: 32,2070 02215 STORE AGSBUFF +12D 008439,000138: 32,2071 77776 EXIT 008440,000139: 008441,000140: 32,2072 34753 CAF LAGSLIST 008442,000141: 32,2073 54332 TS DNLSTCOD 008443,000142: 008444,000143: 32,2074 32176 CAF 20SEC # DELAY FOR 20 SEC WHILE THE AGS 008445,000144: 32,2075 04616 TC BANKCALL # DOWNLIST IS TRANSMITTED 008446,000145: 32,2076 01735 CADR DELAYJOB 008447,000146: 008448,000147: 32,2077 31324 CA AGSWORD 008449,000148: 32,2100 54332 TS DNLSTCOD # RETURN TO THE OLD DOWNLIST 008450,000149: 32,2101 34744 CAF IMUSEBIT 008451,000150: 32,2102 70074 MASK FLAGWRD0 # CHECK IMUSE FLAG. 008452,000151: 32,2103 10000 CCS A 008453,000152: 32,2104 02122 TC AGSEND # IMU IS BEING USED -- DO NOT ZERO 008454,000153: 32,2105 11304 CKSTALL CCS IMUCADR # CHECK FOR IMU USAGE WHICH AVOIDS THE 008455,000154: 32,2106 12111 TCF +3 # IMUSE BIT: I.E., IMU COMPENSATION. 008456,000155: 32,2107 12115 TCF +6 # FREE. GO AHEAD WITH THE IMU ZERO. 008457,000156: 32,2110 12111 TCF +1 008458,000157: 32,2111 34363 +3 CAF TEN # WAIT .1 SEC AND TRY AGAIN. 008459,000158: 32,2112 04616 TC BANKCALL 008460,000159: 32,2113 01735 CADR DELAYJOB 008461,000160: 32,2114 12105 TCF CKSTALL 008462,000161: 008463,000162: 32,2115 04616 +6 TC BANKCALL # IMU IS NOT IN USE 008464,000163: 32,2116 16714 CADR IMUZERO # SET IMU ZERO DISCRETE FOR 320 MSECS. 008465,000164: 32,2117 04616 TC BANKCALL # WAIT 3 SEC FOR COUNTERS TO INCREMENT 008466,000165: 32,2120 17716 CADR IMUSTALL 008467,000166: 32,2121 02122 TC AGSEND 008468,000167: 32,2122 05516 AGSEND TC DOWNFLAG # ALLOW V37 008469,000168: 32,2123 00054 ADRES NODOFLAG 008470,000169: 008471,000170: 32,2124 32173 CAF V50N16 008472,000171: 32,2125 04616 TC BANKCALL 008473,000172: 32,2126 20342 CADR GOMARK3 008474,000173: 32,2127 15472 TCF ENDEXT 008475,000174: 32,2130 15472 TCF ENDEXT 008476,000175: 32,2131 05472 TC ENDEXT 008477,000176: 008478,000177: 32,2132 64375 SCALEVEC VLOAD MXV 008479,000178: 32,2133 00025 VATT1 008480,000179: 32,2134 01734 REFSMMAT 008481,000180: 32,2135 72561 VXSC VSL2 008482,000181: 32,2136 24202 VSCALE 008483,000182: # Page 209 008484,000183: 32,2137 53255 VAD VAD # THIS SECTION ROUNDS THE VECTOR, AND 008485,000184: 32,2140 24204 AGSRND1 # CORRECTS FOR THE FACT THAT THE AGS 008486,000185: 32,2141 24212 AGSRND2 # IS A 2'S COMPLEMENT MACHINE WHILE THE 008487,000186: 32,2142 77634 RTB # LGC IS A 1'S COMPLEMENT MACHINE. 008488,000187: 32,2143 21772 VECSGNAG 008489,000188: 32,2144 24025 STOVL VATT1 008490,000189: 32,2145 00017 RATT1 008491,000190: 32,2146 74321 MXV VXSC 008492,000191: 32,2147 01734 REFSMMAT 008493,000192: 32,2150 24200 RSCALE 008494,000193: 32,2151 53212 VSL8 VAD # AGAIN THIS SECTION ROUNDS. TWO VECTORS 008495,000194: 32,2152 24204 AGSRND1 # ARE ADDED TO DEFEAT ALSIGNAG IN THE 008496,000195: 32,2153 47055 VAD RTB # CASE OF A HIGH-ORDER ZERO COUPLED WITH 008497,000196: 32,2154 24212 AGSRND2 # A LOW ORDER NEGATIVE PART. 008498,000197: 32,2155 21772 VECSGNAG 008499,000198: 32,2156 77750 LXA,1 008500,000199: 32,2157 00024 VATT1 008501,000200: 32,2160 72130 SXA,1 LXA,1 008502,000201: 32,2161 00155 MPAC +1 008503,000202: 32,2162 00026 VATT1 +2 008504,000203: 32,2163 72130 SXA,1 LXA,1 008505,000204: 32,2164 00160 MPAC +4 008506,000205: 32,2165 00030 VATT1 +4 008507,000206: 32,2166 43530 SXA,1 RVQ 008508,000207: 32,2167 00162 MPAC +6 008509,000208: 008510,000209: 32,2170 4753 LAGSLIST = ONE 008511,000210: 32,2170 00216 V01N14 VN 0114 008512,000211: 32,2171 14400 V50N00A VN 5000 008513,000212: 32,2172 6010 V00N25 EQUALS OCT31 008514,000213: 32,2172 01420 V06N16 VN 0616 008515,000214: 32,2173 4242 V00N34 EQUALS 34DEC 008516,000215: 32,2173 14420 V50N16 VN 5016 008517,000216: 32,2174 03100 00000 TSCALE 2DEC 100 B-10 # CSEC TO SEC SCALE FACTOR 008518,000217: 32,2176 03720 20SEC DEC 2000 B-14 008519,000218: 32,2177 15077 05041 RSCALE 2DEC 3.280839 B-3 # METERS TO FEET SCALE FACTOR 008520,000219: 32,2201 24402 25724 VSCALE 2DEC 3.280839 E2 B-9 # METERS/CS TO FEET/SEC SCALE FACTOR 008521,000220: 32,2203 00000 60000 AGSRND1 2OCT 0000060000 008522,000221: 32,2205 00000 60000 2OCT 0000060000 008523,000222: 32,2207 00000 60000 2OCT 0000060000 008524,000223: 32,2211 00000 37777 AGSRND2 2OCT 0000037777 008525,000224: 32,2213 00000 37777 2OCT 0000037777 008526,000225: 32,2215 S # Page 210 008527,000226: 32,2215 00000 37777 2OCT 0000037777 008528,000227: 008529,000228: 32,2217 30,2000 SBANK= LOWSUPER # FOR SUBSEQUENT LOW 2CADRS. 008530,000229: End of include-file AGS_INITIALIZATION.agc. Parent file is MAIN.agc