Source Code
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This source code is very close to the Apollo Guidance Computer software for the
Apollo 13 Lunar module. This revision of the Luminary 131 program is from December
of 1969, whereas there was a later revision in January of 1970, and still another
revision in February, which is the code that flew on the mission.
As far as this transcription is concerned, it was originally from a copy made in 1991 of
a printout from the collection of AGC developer Don Eyles for collector David Craig.
It was subsequently scanned by Gary Neff, reprocessed for online
presentation at the now-discontinued History of Recent Science and Technology (HRST) website
of MIT's Dibner Institute (the full-quality scans being discarded in the process),
and finally transcribed by Ron Burkey for the Virtual AGC Project. Although a
high-quality replacement scan for a completely illegible page was later provided by Gary
Neff, the reduced legibility of the reprocessed HRST posting nevertheless caused many
errors to be introduced into the transcription. Accordingly, a second scan of the same physical
printout was made in 2017 for the Virtual AGC Project's collection at the Internet Archive,
and used to correct the transcription errors. All of the scanned materials mentioned,
as well as other Luminary 131 related material, are available online.
Don Eyles apprently made additional hand-written notes in printout between 1991 and 2017,
so the two scans are not identical in that respect. The page-headings in the printout read, in part:GAP: ASSEMBLE REVISION 131 OF AGC PROGRAM LUMINARY BY NASA 2021112-091 17:53 DEC. 19, 1969Note that the date is the date the printout was made, not the date on which the program revision was released, although these happen to be very close together. |
059185,000002: ## Copyright: Public domain.
059186,000003: ## Filename: DAPIDLER_PROGRAM.agc
059187,000004: ## Purpose: A section of Luminary 1C, revision 131.
059188,000005: ## It is part of the source code for the Lunar Module's (LM)
059189,000006: ## Apollo Guidance Computer (AGC) for Apollo 13.
059190,000007: ## This file is intended to be a faithful transcription, except
059191,000008: ## that the code format has been changed to conform to the
059192,000009: ## requirements of the yaYUL assembler rather than the
059193,000010: ## original YUL assembler.
059194,000011: ## Reference: pp. 1402-1412
059195,000012: ## Contact: Ron Burkey <info@sandroid.org>.
059196,000013: ## Website: www.ibiblio.org/apollo/index.html
059197,000014: ## Mod history: 06/07/03 RSB. Began transcribing.
059198,000015: ## 05/14/05 RSB Corrected website reference above.
059199,000016: ## 2017-01-06 RSB Page numbers now agree with those on the
059200,000017: ## original hardcopy, as opposed to the PDF page
059201,000018: ## numbers in 1701.pdf.
059202,000019: ## 2017-01-28 RSB Comment-text fixes identified for Luminary 69.
059203,000020: ## 2017-02-28 RSB Proofed comment text using octopus/ProoferComments.
059204,000021: ## 2017-03-10 RSB Comment-text fixes noted in proofing Luminary 116.
059205,000022:
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Page 1402 |
059207,000024: # THE DAPIDLER PROGRAM IS STARTED BY FRESH START AND RESTART. THE DAPIDLER PROGRAM IS DONE 10 TIMES
059208,000025: # PER SECOND UNTIL THE ASTRONAUT DESIRES THE DAP TO WAKE UP, AND THE IMU AND CDUS ARE READY FOR USE BY THE DAP.
059209,000026: # THE NECESSARY INITIALIZATION OF THE DAP IS DONE BY THE DAPIDLER PROGRAM.
059210,000027:
059211,000028: 16,2000 BANK 16
059212,000029: 16,2000 SETLOC DAPS1
059213,000030: 16,2000 BANK
059214,000031:
059215,000032: 16,2000 E6,1536 EBANK= AOSQ
059216,000033:
059217,000034: 16,2000 COUNT* $$/DAPID
059218,000035:
059219,000036: 16,2000 00006 CHEKBITS EXTEND
059220,000037: 16,2001 00031 READ CHAN31 # IF BOTH BIT13 AND BIT14 ARE ONE, THEN
059221,000038: 16,2002 40000 COM # THE MODE SELECT SWITCH IS IN THE OFF
059222,000039: 16,2003 74355 MASK BIT13-14 # POSITION, AND SO THE DAP SHOULD BE OFF,
059223,000040: 16,2004 00006 EXTEND # WITH NO ATTITUDE ERROR DISPLAY.
059224,000041: 16,2005 12157 BZF MOREIDLE
059225,000042:
059226,000043: 16,2006 41300 CS IMODES33
059227,000044: 16,2007 74746 MASK BIT6
059228,000045: 16,2010 10000 CCS A
059229,000046: 16,2011 12206 TCF JUMPDSP
059230,000047: 16,2012 41262 CS RCSFLAGS # IMU NOT USABLE. SET UP INITIALIZATION
059231,000048: 16,2013 74751 MASK BIT3 # FLAG FOR ATT ERROR DISPLAY ROUTINE.
059232,000049: 16,2014 27262 ADS RCSFLAGS
059233,000050: 16,2015 12163 TCF SHUTDOWN
059234,000051:
059235,000052: 16,2016 34742 CHEKMORE CAF BIT10 # BIT 10 OF 30 IS PGNCS CONTROL OF S/C
059236,000053: 16,2017 00006 EXTEND
059237,000054: 16,2020 02030 RAND CHAN30 # BITS IN 30 ARE INVERTED
059238,000055: 16,2021 10000 CCS A
059239,000056: 16,2022 12157 TCF MOREIDLE
059240,000057:
059241,000058: 16,2023 00002 RETURN
059242,000059:
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Page 1403 |
059244,000061: # DAPIDLER ENTRY.
059245,000062:
059246,000063: 16,2024 22016 DAPIDLER LXCH BANKRUPT # INTERRUPT LEAD INS (CONTINUED)
059247,000064: 16,2025 00006 EXTEND
059248,000065: 16,2026 22012 QXCH QRUPT
059249,000066:
059250,000067: 16,2027 31262 CA RCSFLAGS
059251,000068: 16,2030 74737 MASK BIT13
059252,000069: 16,2031 10000 CCS A # CHECK IF 1/ACCJOB HAS BEEN SET UP SINCE
059253,000070: 16,2032 12041 TCF CHECKUP # THE LAST FRESH START OR RESTART.
059254,000071: 16,2033 34737 CA BIT13
059255,000072: 16,2034 27262 ADS RCSFLAGS # BIT 13 IS 1.
059256,000073: 16,2035 37720 CAF PRIO27
059257,000074: 16,2036 05072 TC NOVAC # SET UP JOB TO DO A LITTLE INITIALIZATION
059258,000075: 16,2037 E6,1536 EBANK= AOSQ # AND EXECUTE 1/ACCS.
059259,000076: 16,2037 03645 42106 2CADR 1/ACCSET # (WILL BRANCH TO MOREIDLE ON ACCSOKAY)
059260,000077:
059261,000078: 16,2041 02000 CHECKUP TC CHEKBITS # CHECK TO SEE IF LM DAP IS TO GO ON AND
059262,000079: # DO ERROR DISPLAY.
059263,000080:
059264,000081: 16,2042 30111 CAE DAPBOOLS # IF 1/ACCS HAS NOT BEEN COMPLETED, IDLE.
059265,000082: 16,2043 74751 MASK ACCSOKAY # NOTE: ONLY FRESH START AND RESTART
059266,000083: 16,2044 00006 EXTEND # KNOCK THIS BIT DOWN.
059267,000084: 16,2045 12157 BZF MOREIDLE
059268,000085:
059269,000086: 16,2046 04674 STARTDAP TC IBNKCALL # ZERO ATTITUDE ERROR AND DESIRED RATES.
059270,000087: 16,2047 40154 FCADR ZATTEROR
059271,000088: 16,2050 34755 CAF ZERO # ********** INITIALIZE: **********
059272,000089: 16,2051 55524 TS TJP
059273,000090: 16,2052 55525 TS TJU
059274,000091: 16,2053 55526 TS TJV
059275,000092: 16,2054 55421 TS OMEGAP # RATES IN BODY (PILOT) COORDINATES.
059276,000093: 16,2055 55422 TS OMEGAQ
059277,000094: 16,2056 55423 TS OMEGAR
059278,000095: 16,2057 55430 TS TRAPEDP
059279,000096: 16,2060 55431 TS TRAPEDQ
059280,000097: 16,2061 55432 TS TRAPEDR
059281,000098: 16,2062 55536 TS AOSQ # OFFSET ACCELERATION ESTIMATES.
059282,000099: 16,2063 55537 TS AOSQ +1
059283,000100: 16,2064 55540 TS AOSR
059284,000101: 16,2065 55541 TS AOSR +1
059285,000102: 16,2066 55424 TS ALPHAQ # COPIES OF OFFSET ESTIMATES FOR DOWNLIST.
059286,000103: 16,2067 55425 TS ALPHAR
059287,000104: 16,2070 55501 TS NEGUQ
059288,000105: 16,2071 55503 TS NEGUR
059289,000106: 16,2072 55544 TS AOSQTERM # QRAXIS RATE DERIVATION TERMS AND KALMAN
059290,000107: 16,2073 55545 TS AOSRTERM # FILTER INITIALIZATION TERMS.
059291,000108: 16,2074 55510 TS QACCDOT # DESCENT ACCELERATION DERIVATIVE EST.
059292,000109: 16,2075 55512 TS RACCDOT
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Page 1404 |
059294,000111: 16,2076 55502 TS ALLOWGTS # AOSTASK FLAG FOR QRAXIS RCS CONTROL USE.
059295,000112: 16,2077 55630 TS COTROLER # DO TRYGTS ON FIRST PASS (WILL GO TO RCS)
059296,000113: 16,2100 55632 TS INGTS # RECOGNIZE FIRST GTS PASS AS SUCH.
059297,000114: 16,2101 55631 TS QGIMTIMR # STOP GIMBAL DRIVES. (PROBABLY WOULD BE
059298,000115: 16,2102 55633 TS RGIMTIMR # GOOD ENOUGH JUST TO INACTIVATE TIMERS)
059299,000116: 16,2103 55460 TS OLDPMIN # MINIMUM IMPULSE MODE ERASABLES
059300,000117: 16,2104 55461 TS OLDQRMIN
059301,000118: 16,2105 55766 TS PJETCTR # INITIALIZE DOCKED JET INHIBITION
059302,000119: 16,2106 55767 TS UJETCTR # COUNTERS
059303,000120: 16,2107 55770 TS VJETCTR
059304,000121: 16,2110 4747 CALLGMBL EQUALS BIT5 # RCSFLAGS INITIALIZATION.
059305,000122: 16,2110 42202 CS MANFLAG
059306,000123: 16,2111 71262 MASK RCSFLAGS # NEGUQ(R) HAVE BEEN GENERATED.
059307,000124: 16,2112 55262 TS RCSFLAGS
059308,000125:
059309,000126: # SET UP "OLD" MEASURED CDU ANGLES:
059310,000127:
059311,000128: 16,2113 00006 EXTEND
059312,000129: 16,2114 30033 DCA CDUX # OLDXFORP AND OLDYFORP
059313,000130: 16,2115 53441 DXCH OLDXFORP
059314,000131: 16,2116 30034 CA CDUZ
059315,000132: 16,2117 55442 TS OLDZFORQ
059316,000133: 16,2120 41262 CS RCSFLAGS
059317,000134: 16,2121 74740 MASK BIT12
059318,000135: 16,2122 27262 ADS RCSFLAGS # BIT 12 SET TO 1.
059319,000136: 16,2123 34751 CA FOUR
059320,000137: 16,2124 55534 TS SKIPU
059321,000138: 16,2125 55535 TS SKIPV
059322,000139: 16,2126 34733 CA POSMAX
059323,000140: 16,2127 54031 TS TIME6
059324,000141: 16,2130 55466 TS T6NEXT
059325,000142: 16,2131 55470 TS T6FURTHA
059326,000143: 16,2132 34755 CA ZERO
059327,000144: 16,2133 55467 TS T6NEXT +1
059328,000145: 16,2134 55471 TS T6FURTHA +1
059329,000146: 16,2135 55465 TS NXT6ADR
059330,000147: 16,2136 55472 TS NEXTP
059331,000148: 16,2137 55473 TS NEXTU
059332,000149: 16,2140 55474 TS NEXTV
059333,000150: 16,2141 44363 CS TEN
059334,000151: 16,2142 55756 TS DAPZRUPT # JASK NOT IN PROGRESS, INITIALIZE NEG.
059335,000152: 16,2143 34752 CA TWO
059336,000153: 16,2144 55433 TS NPTRAPS
059337,000154: 16,2145 55434 TS NQTRAPS
059338,000155: 16,2146 55435 TS NRTRAPS
059339,000156: 16,2147 00006 EXTEND
059340,000157: 16,2150 32205 DCA PAXADIDL
059341,000158: 16,2151 53264 DXCH T5ADR
059342,000159: 16,2152 37732 SETTIME5 CAF MS100
059343,000160: 16,2153 54030 TS TIME5
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Page 1405 |
059345,000162: 16,2154 15270 TCF RESUME
059346,000163: 16,2155 E6,1536 EBANK= AOSQ
059347,000164: 16,2155 02024 34106 IDLERADR 2CADR DAPIDLER
059348,000165:
059349,000166: 16,2157 04674 MOREIDLE TC IBNKCALL # CALCULATE Q,R-AXES ATTITUDE ERRORS.
059350,000167: 16,2160 36655 CADR QERRCALC
059351,000168:
059352,000169: 16,2161 04674 TC IBNKCALL
059353,000170: 16,2162 35452 CADR CALCPERR # CALCULATE P AXIS ATTITUDE ERRORS.
059354,000171:
059355,000172: 16,2163 00006 SHUTDOWN EXTEND
059356,000173: 16,2164 32156 DCA IDLERADR
059357,000174: 16,2165 53264 DXCH T5ADR
059358,000175:
059359,000176: 16,2166 34755 CAF ZERO # KILL ANY POSSIBLE JET REQUESTS
059360,000177: 16,2167 55472 TS NEXTP
059361,000178: 16,2170 55473 TS NEXTU
059362,000179: 16,2171 55474 TS NEXTV
059363,000180: 16,2172 00006 EXTEND # COMMAND JETS OFF.
059364,000181: 16,2173 01005 WRITE CHAN5
059365,000182: 16,2174 00006 EXTEND
059366,000183: 16,2175 01006 WRITE CHAN6
059367,000184: 16,2176 42203 CS BGIM23 # TURN TRIM GIMBAL OFF
059368,000185: 16,2177 00006 EXTEND
059369,000186: 16,2200 03012 WAND CHAN12
059370,000187: 16,2201 12152 TCF SETTIME5 # RETURN IN 100 MSEC.
059371,000188:
059372,000189: 16,2202 03021 MANFLAG OCT 03021
059373,000190: 16,2203 07400 BGIM23 OCTAL 07400
059374,000191: 16,2204 E6,1421 EBANK= OMEGAP
059375,000192: 16,2204 02213 34106 PAXADIDL 2CADR PAXIS
059376,000193:
059377,000194: 16,2206 7732 MS100 = OCT37766
059378,000195: 16,2206 0061 COSMG = ITEMP1
059379,000196: 16,2206 00006 JUMPDSP EXTEND # TRANSFER TO BANK 20
059380,000197: 16,2207 32212 DCA DSPCADR # FOR ATTITUDE ERROR DISPLAYS
059381,000198: 16,2210 52006 DTCB
059382,000199:
059383,000200: 16,2211 E6,1760 EBANK= AK
059384,000201: 16,2211 02227 40106 DSPCADR 2CADR ALTDSPLY
059385,000202:
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Page 1406 |
059387,000204: 20,2227 BANK 20
059388,000205: 20,2000 SETLOC DAPS3
059389,000206: 20,2000 BANK
059390,000207: 20,2227 COUNT* $$/NEEDL
059391,000208:
059392,000209: # PROGRAM: ALTDSPLY
059393,000210: # MOD 0. 6 DEC 1967
059394,000211: # AUTHOR: CRAIG WORK, DON KEENE, MIT IL
059395,000212: # MOD 3 BY DON KEENE AUG 1, 1968 MOVED PROGRAM TO BANK 20
059396,000213:
059397,000214: # PROGRAM DESCRIPTION:
059398,000215: # ALTDSPLY REVERSES THE DSPLYALT BIT OF RCSFLAGS EACH TIME IT IS CALLED, WHICH IS PRESUMABLY EVERY 100 MS.
059399,000216: # IF THE REVERSED BIT IS ONE, NEEDLER IS CALLED TO DISPLAY ATTITUDE ERRORS. IF THE BIT IS ZERO, THE ATTITUDE ERR-
059400,000217: # ORS ARE CALCULATED AS 1) ESTIMATED RATES (FOLLOWING) IF NEED2FLG = 1, OTHERWISE AS 2) DAP FOLLOWING ERRORS FOR
059401,000218: # NEEDLFLG = 0 AND 3) TOTAL ATTITUDE ERRORS FOR NEEDLFLG = 1.
059402,000219:
059403,000220: # WARNING: ALTDSPLY MAY ONLY BE CALLED WITH INTERRUPT INHIBITED.
059404,000221:
059405,000222: # WARNING: EBANK MUST BE SET TO 6 WHEN USING THIS ROUTINE.
059406,000223:
059407,000224: # INPUT: RCSFLAGS AND 1) IF NEEDLFLG = 0, INPUT PERROR, QERROR, RERROR.
059408,000225: # 2) IF NEEDLFLG = 1, INPUT CPHI,CTHETA,CPSI,CDUX,CDUY,CDUZ,M11,M21,M32,M22,M32. (GPMATRIX)
059409,000226: # 3) IF NEED2FLG = 1, INPUT OMEGAP, OMEGAQ, AND OMEGAR.
059410,000227:
059411,000228: # OUTPUTS: RCSFLAGS WITH DSPLYALT REVERSED, AK, AK1, AK2, + NEEDLER OUTPUTS.
059412,000229:
059413,000230: # ENTRY: TCF ALTDSPLY
059414,000231:
059415,000232: # EXIT: TCF CHEKMORE
059416,000233:
059417,000234: # ALARM OR ABORT EXITS: NONE
059418,000235:
059419,000236: # SUBPROGRAMS CALLED: NEEDLER, OVERSUB2
059420,000237:
059421,000238: # DEBRIS: A, L, AND NEEDLER DEBRIS.
059422,000239:
059423,000240: 20,2227 31262 ALTDSPLY CA RCSFLAGS # INVERT THE DISPLAY ALTERNATION BIT.
059424,000241: 20,2230 54001 TS L
059425,000242: 20,2231 34750 CA DSPLYALT
059426,000243: 20,2232 00006 EXTEND
059427,000244: 20,2233 06001 RXOR LCHAN
059428,000245: 20,2234 55262 TS RCSFLAGS
059429,000246:
059430,000247: 20,2235 74750 MASK DSPLYALT
059431,000248: 20,2236 10000 CCS A # IS ALTERNATION FLAG ZERO?
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Page 1407 |
059433,000250: 20,2237 12336 TCF NEEDLER
059434,000251:
059435,000252: 20,2240 40074 CS FLAGWRD0 # CHECK FOR RATE DISPLAY TO ERROR NEEDLES
059436,000253: 20,2241 74735 MASK NEED2BIT # VIA EXTENDED VERB 60
059437,000254: 20,2242 00006 EXTEND
059438,000255: 20,2243 12257 BZF DISPRATE
059439,000256:
059440,000257: 20,2244 30074 CAE FLAGWRD0 # NEEDLFLG WILL INDICATE TOTAL OR DAP AT-
059441,000258: 20,2245 74750 MASK NEEDLBIT # TITUDE ERROR DISPLAY REQUEST.
059442,000259: 20,2246 10000 CCS A
059443,000260: 20,2247 12266 TCF DSPLYTOT # TOTAL ERROR IS NEEDED IN AK, AK +1, AK +2
059444,000261:
059445,000262: 20,2250 41450 CS QERROR # YES. DISPLAY ATT ERRORS ON THE ,-BALL.
059446,000263: 20,2251 55761 TS AK +1 # ERROR COMPLEMENTS ARE INPUT TO NEEDLER.
059447,000264: 20,2252 41452 CS RERROR
059448,000265: 20,2253 55762 TS AK +2
059449,000266: 20,2254 41464 CS PERROR
059450,000267: 20,2255 57760 XCH AK
059451,000268:
059452,000269: 20,2256 12456 TCF RETNMORE # DISPLAY THESE THE NEXT TIME THROUGH
059453,000270:
059454,000271: 20,2257 41422 DISPRATE CS OMEGAQ # LOAD ESTIMATED RATES (FOLLOWING)
059455,000272: 20,2260 55761 TS AK +1
059456,000273: 20,2261 41423 CS OMEGAR
059457,000274: 20,2262 55762 TS AK +2
059458,000275: 20,2263 41421 CS OMEGAP
059459,000276: 20,2264 57760 XCH AK
059460,000277: 20,2265 12456 TCF RETNMORE
059461,000278:
059462,000279: # CALCULATE GIMBAL ANGLE TOTAL ERRORS, RESOLVE INTO PILOT AXES, STORE TOTAL ERRORS FOR NEEDLER. Q-AXIS FIRST.
059463,000280:
059464,000281: 20,2266 00006 DSPLYTOT EXTEND
059465,000282: 20,2267 22061 QXCH ITEMP1 # SAVE Q FOR CHEKBITS RETURN.
059466,000283:
059467,000284: 20,2270 30322 CA CTHETA # DESIRED ATTITUDE, Y-AXIS, 2'S COMP.
059468,000285: 20,2271 00006 EXTEND # SUBTRACT CURRENT ATTITUDE.
059469,000286: 20,2272 20033 MSU CDUY # DIFFERENCE SCALED AT PI, 1'S COMP.
059470,000287: 20,2273 55760 TS AK # SAVE FOR R-ERROR CALCULATION.
059471,000288: 20,2274 00006 EXTEND
059472,000289: 20,2275 71415 MP M21 # (CHTETA-CDUY)*M21 SCALED AT PI RADIANS.
059473,000290: 20,2276 57761 XCH AK +1 # STORE FIRST TERM OF Q ERROR.
059474,000291: 20,2277 30323 CA CPSI # DESIRED ATTITUDE, Z-AXIS, 2'S COMP.
059475,000292: 20,2300 00006 EXTEND # SUBTRACT CURRENT ATTITUDE.
059476,000293: 20,2301 20034 MSU CDUZ # DIFFERENCE SCALED AT PI, 1'S COMP.
059477,000294: 20,2302 55762 TS AK +2 # SAVE Z-AXIS TERM FOR R ERROR CALCULATION
059478,000295: 20,2303 00006 EXTEND
059479,000296: 20,2304 71417 MP M22 # (CPSI-CDUZ)*M22, SCALED AT PI RADIANS.
059480,000297: 20,2305 61761 AD AK +1 # Q ERROR COMPLETE , AT PI RAD.
059481,000298: 20,2306 02451 TC OVERSUB2 # PIN NEEDLES IN CASE OF OVERFLOW.
059482,000299: 20,2307 55761 TS AK +1
059483,000300:
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Page 1408 |
059485,000302: # R ERROR CALCULATION NEXT.
059486,000303:
059487,000304: 20,2310 31760 CA AK # Y-AXIS DIFFERENCE STORED BY Q-AXIS CALC.
059488,000305: 20,2311 00006 EXTEND
059489,000306: 20,2312 71416 MP M31 # (CTHETA-CDUY)*M31, SCALED AT PI RADIANS.
059490,000307: 20,2313 57762 XCH AK +2 # FIRST TERM OF R ERROR.
059491,000308: # Z-AXIS DIFFERENCE, STORED BY A CALC. IS
059492,000309: 20,2314 00006 EXTEND # RECOVERED BY THE EXCHANGE.
059493,000310: 20,2315 71420 MP M32 # (CPSI-CDUZ)*M32, SCALED AT PI RADIANS.
059494,000311: 20,2316 61762 AD AK +2 # R ERROR COMPLETE , AT PI RAD.
059495,000312: 20,2317 02451 TC OVERSUB2 # PIN NEEDLES IN CASE OF OVERFLOW.
059496,000313: 20,2320 55762 TS AK +2
059497,000314:
059498,000315: # NOW CALCULATE P ERROR. (NOTE THAT M13 = 1, SCALED AT 1, SO THE MULTIPLICATION IS BY-PASSED.)
059499,000316:
059500,000317: 20,2321 31760 CA AK # Y-AXIS DIFFERENCE STORED BY Q AXIS CALC.
059501,000318: 20,2322 00006 EXTEND
059502,000319: 20,2323 71414 MP M11 # (CTHETA-CDUY)*M11 SCALED AT PI RADIANS.
059503,000320: 20,2324 57760 XCH AK # FIRST TERM OF P ERROR IN AK, AT PI RAD.
059504,000321: 20,2325 30321 CAE CPHI # DESIRED ATTITUDE, X-AXIS, 2'S COMP.
059505,000322: 20,2326 00006 EXTEND # SUBTRACT CURRENT X ATTITUDE.
059506,000323: 20,2327 20032 MSU CDUX # X-AXIS DIFFERENCE, 1'S COMP, AT PI RAD.
059507,000324:
059508,000325: # M13 = 1, SO BYPASS THE MULTIPLICATION.
059509,000326: # EXTEND
059510,000327: # MP M13 (CPHI-CDUX)*M13 SCALED AT PI RADIANS.
059511,000328:
059512,000329: 20,2330 61760 AD AK # P ERROR COMPLETE , SCALED AT PI RAD
059513,000330: 20,2331 02451 TC OVERSUB2 # PIN NEEDLES IN CASE OF OVERFLOW.
059514,000331: 20,2332 55760 TS AK
059515,000332:
059516,000333: 20,2333 00006 EXTEND
059517,000334: 20,2334 22061 QXCH ITEMP1 # RESTORE Q FOR CHEKBITS RETURN.
059518,000335:
059519,000336: 20,2335 12456 TCF RETNMORE # DISPLAY THESE THE NEXT TIME THROUGH
059520,000337:
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Page 1409 |
059522,000339: # FDAI ATTITUDE ERROR DISPLAY SUBROUTINE
059523,000340:
059524,000341: # PROGRAM DESCRIPTION: D. KEENE 5/24/67
059525,000342: # MOD 1 BY CRAIG WORK, 12 DEC 67
059526,000343: # MOD 2 BY CRAIG WORK, 6 APRIL 68 CONVERTS ATTITUDE ERROR DISPLAY SCALING FROM 16 7/8 DEG. TO 42 3/16 DEGREES.
059527,000344:
059528,000345: # THIS SUBROUTINE IS USED TO DISPLAY ATTITUDE ERRORS ON THE FDAI VIA THE DIGITAL TO ANALOG CONVERTERS (DACS)
059529,000346: # IN THE CDUS. CARE IS TAKEN TO METER OUT THE APPROPRIATE NUMBER OF PULSES TO THE IMU ERROR COUNTERS AND PREVENT
059530,000347: # OVERFLOW, TO CONTROL THE RELAY SEQUENCING, AND TO AVOID INTERFERENCE WITH THE COARSE ALIGN LOOP WHICH ALSO USES
059531,000348: # THE DACS.
059532,000349:
059533,000350: # CALLING SEQUENCE:
059534,000351: # DURING THE INITIALIZATION SECTION OF THE USER'S PROGRAM, BIT3 OF RCSFLAGS SHOULD BE SET TO INITIATE THE
059535,000352: # TURN-ON SEQUENCE WITHIN THE NEEDLES PROGRAM:
059536,000353: # CS RCSFLAGS IN EBANK6
059537,000354: # MASK BIT3
059538,000355: # ADS RCSFLAGS
059539,000356: # THEREAFTER, THE ATTITUDE ERRORS GENERATED BY THE USER SHOULD BE TRANSFERED TO THE FOLLOWING LOCATIONS IN EBANK6:
059540,000357: # AK SCALED 180 DEGREES NOTE: THESE LOCATIONS ARE SUBJECT
059541,000358: # AK1 SCALED 180 DEGREES TO CHANGE
059542,000359: # AK2 SCALED 180 DEGREES
059543,000360: # FULL SCALED DEFLECTION OF THE NEEDLES CORRESPONDS TO 5 1/16 DEGREES, WHILE 384 BITS IN THE IMU ERROR COUNTER
059544,000361: # CORRESPONDS TO 42 3/16 DEGREES. (DAC MAXIMUM CAPACITY IS 384 BITS.) 46 BITS EFFECTIVELY PIN THE NEEDLES.
059545,000362: # FOR RATE DISPLAY, FULL SCALE NEEDLE DEFLECTION IS 1 17/64 DEG/SEC, AND A FULL COUNTER IS ABOUT 10.5 DEG/SEC.
059546,000363: # A CALL TO NEEDLER WILL THEN UPDATE THE DISPLAY:
059547,000364: # INHINT
059548,000365: # TC IBNKCALL NOTE: EBANK SHOULD BE SET TO E6
059549,000366: # CADR NEEDLER
059550,000367: # RELINT
059551,000368: # THIS PROCESS SHOULD BE REPEATED EACH TIME THE ERRORS ARE UPDATED. AT LEAST 3 PASSES THRU THE PROGRAM ARE
059552,000369: # REQUIRED BEFORE ANYTHING IS ACTUALLY DISPLAYED ON THE ERROR METERS.
059553,000370: # NOTE: EACH CALL TO NEEDLER MUST BE SEPARATED BY AT LEAST 50 MS TO ASSURE PROPER RELAY SEQUENCING.
059554,000371:
059555,000372: # ERASABLE USED:
059556,000373: # AK CDUXCMD
059557,000374: # AK1 CDUYCMD
059558,000375: # AK2 CDUZCMD
059559,000376: # EDRIVEX A,L,Q
059560,000377: # EDRIVEY T5TEMP
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Page 1410 |
059562,000379: # EDRIVEZ DINDX
059563,000380:
059564,000381: # SWITCHES: RCSFLAGS BITS 3,2
059565,000382:
059566,000383: # I/O CHANNELS: CHAN12 BIT 4 (COARSE ALIGN - READ ONLY)
059567,000384: # CHAN12 BIT 6 (IMU ERROR COUNTER ENABLE)
059568,000385: # CHAN14 BIT 13,14,15 (DAC ACTIVITY)
059569,000386:
059570,000387: # SIGN CONVENTION< AK = THETAC - THETA
059571,000388: # WHERE THETAC = COMMAND ANGLE
059572,000389: # THETA = PRESENT ANGLE
059573,000390:
059574,000391: 20,2336 31262 NEEDLER CA RCSFLAGS
059575,000392: 20,2337 76245 MASK SIX
059576,000393: 20,2340 00006 EXTEND
059577,000394: 20,2341 12376 BZF NEEDLES3
059578,000395: 20,2342 74751 MASK BIT3
059579,000396: 20,2343 00006 EXTEND
059580,000397: 20,2344 12367 BZF NEEDLER2 # BIT3 = 0, BIT2 = 1
059581,000398:
059582,000399: 20,2345 44746 CS BIT6 # FIRST PASS BIT3 = 1
059583,000400: 20,2346 00006 EXTEND # DISABLE IMU ERROR COUNTER TO ZERO DACS
059584,000401: 20,2347 03012 WAND CHAN12 # MUST WAIT AT LEAST 60 MS BEFORE
059585,000402: 20,2350 44755 NEEDLE11 CS ZERO # ENABLING COUNTERS.
059586,000403: 20,2351 55760 TS AK # ZERO THE INPUTS ON FIRST PASS
059587,000404: 20,2352 55761 TS AK1
059588,000405: 20,2353 55762 TS AK2
059589,000406: 20,2354 55763 TS EDRIVEX # ZERO THE DISPLAY REGISTERS
059590,000407: 20,2355 55764 TS EDRIVEY
059591,000408: 20,2356 55765 TS EDRIVEZ
059592,000409: 20,2357 54050 TS CDUXCMD # ZERO THE OUT COUNTERS
059593,000410: 20,2360 54051 TS CDUYCMD
059594,000411: 20,2361 54052 TS CDUZCMD
059595,000412: 20,2362 46245 CS SIX # RESET RCSFLAGS FOR PASS2
059596,000413: 20,2363 71262 MASK RCSFLAGS
059597,000414: 20,2364 64752 AD BIT2
059598,000415: 20,2365 55262 TS RCSFLAGS
059599,000416: 20,2366 12456 TCF RETNMORE
059600,000417:
059601,000418: 20,2367 34746 NEEDLER2 CAF BIT6 # ENABLE IMU ERROR COUNTERS
059602,000419: 20,2370 00006 EXTEND
059603,000420: 20,2371 05012 WOR CHAN12
059604,000421: 20,2372 46245 CS SIX # RESET RCSFLAGS TO DISPLAY ATTITUDE
059605,000422: 20,2373 71262 MASK RCSFLAGS # ERRORS WAIT AT LEAST 4 MS FOR
059606,000423: 20,2374 55262 TS RCSFLAGS # RELAY CLOSURE
059607,000424: 20,2375 12456 TCF RETNMORE
059608,000425:
059609,000426: 20,2376 34746 NEEDLES3 CAF BIT6 # CHECK TO SEE IF IMU ERROR COUNTER
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Page 1411 |
059611,000428: 20,2377 00006 EXTEND # IS ENABLED
059612,000429: 20,2400 02012 RAND CHAN12
059613,000430: 20,2401 10000 CCS A # IF NOT, RE-INITIALIZE NEEDLER.
059614,000431: 20,2402 12407 TCF NEEDLES
059615,000432:
059616,000433: 20,2403 41262 CS RCSFLAGS # SET UP INITIALIZATION FLAG IN RCSFLAGS.
059617,000434: 20,2404 74751 MASK BIT3
059618,000435: 20,2405 27262 ADS RCSFLAGS
059619,000436: 20,2406 12456 TCF RETNMORE
059620,000437:
059621,000438: 20,2407 34752 NEEDLES CAF TWO
059622,000439: 20,2410 54063 DACLOOP TS DINDX
059623,000440: 20,2411 42450 CS ONETENTH # RESCALE INPUTS TO + OR - 1800 DEGREES.
059624,000441: 20,2412 00006 EXTEND
059625,000442: 20,2413 50063 INDEX DINDX
059626,000443: 20,2414 71760 MP AK
059627,000444: 20,2415 54001 TS L
059628,000445: 20,2416 10000 CCS A
059629,000446: 20,2417 32446 CA DACLIMIT
059630,000447: 20,2420 12422 TCF +2
059631,000448: 20,2421 42446 CS DACLIMIT
059632,000449: 20,2422 60001 AD L
059633,000450: 20,2423 54061 TS T5TEMP # OVFLO CHK
059634,000451: 20,2424 12430 TCF +4
059635,000452: 20,2425 50000 INDEX A # ON OVERFLOW LIMIT OUTPUT TO +-384
059636,000453: 20,2426 32446 CAF DACLIMIT
059637,000454: 20,2427 54001 TS L
059638,000455: 20,2430 50063 INDEX DINDX
059639,000456: 20,2431 41763 CS EDRIVEX # CURRENT VALUE OF DAC
059640,000457: 20,2432 60001 AD L
059641,000458: 20,2433 50063 INDEX DINDX
059642,000459: 20,2434 26050 ADS CDUXCMD
059643,000460: 20,2435 50063 INDEX DINDX
059644,000461: 20,2436 23763 LXCH EDRIVEX
059645,000462: 20,2437 10063 CCS DINDX
059646,000463: 20,2440 12410 TCF DACLOOP
059647,000464: 20,2441 37743 CAF 13,14,15
059648,000465: 20,2442 00006 EXTEND
059649,000466: 20,2443 05014 WOR CHAN14 # SET DAC ACTIVITY BITS
059650,000467: 20,2444 12456 TCF RETNMORE
059651,000468:
059652,000469: 20,2445 77177 DEC -384 B-14
059653,000470: 20,2446 37200 DACLIMIT DEC 16000 B-14
059654,000471: 20,2447 00600 DEC 384 B-14
059655,000472:
059656,000473: 20,2450 03146 ONETENTH OCT 03146 # DECIMAL +0.1, SCALED AT 1.
059657,000474: 20,2451 4750 DSPLYALT EQUALS BIT4 # 100 MS ALTERNATION BIT IN RCSFLAGS
059658,000475:
059659,000476: 20,2451 54007 OVERSUB2 TS 7 # RETURNS A UNCHANGED OR LIMITED TO
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Page 1412 |
059661,000478: 20,2452 00002 TC Q # POSMAX OR NEGMAX IF A HAS OVERFLOW
059662,000479: 20,2453 50000 INDEX A
059663,000480: 20,2454 44734 CS LIMITS # DUPLICATE CODING IN BANK 16
059664,000481: 20,2455 00002 TC Q
059665,000482:
059666,000483: 20,2456 00006 RETNMORE EXTEND # RETURN TO CHEKMORE
059667,000484: 20,2457 32462 DCA MORECADR
059668,000485: 20,2460 52006 DTCB
059669,000486:
059670,000487: 20,2461 E6,1536 EBANK= AOSQ
059671,000488: 20,2461 02016 34106 MORECADR 2CADR CHEKMORE
059672,000489:
059673,000490:
059674,000491:
059675,000492:
End of include-file DAPIDLER_PROGRAM.agc. Parent file is MAIN.agc