Source Code

These source-code files are part of a reconstructed copy of Comanche 51, the initial release (though not the final mission release) of the Apollo 11 Command Module (CM) Apollo Guidance Computer (AGC) software. The flown, final release was Comanche 55. The reconstruction is believed to be exactly accurate, but in the absence of an actual Apollo-era listing of Comanche 51, some explanation of the reconstruction process is needed to insure confidence in that accuracy.

The starting point was the source code of Comanche 55, whose original source code is available. Comanche 55 source code was then modified by undoing changes known to have been made between revisions 51 and 55. The most-significant steps involved reverting changes related to the R-2 lunar potential model, the details of which were known from the previous, separate, independent reconstruction of the Apollo 10 Lunar Module software Luminary 69/2. The now-reconstructed Comanche 51 source code was verified by assembling it and checking that the assembled code had the expected known-correct memory-bank checksums. Note that page numbers in the reconstructed code match those on the Comanche 55 or Luminary 69 printouts, although the source code would likely have different page numbers in a contemporary Comanche 51 listing.

Annotations that were not present in the contemporary source code have been added to the reconstructed code to justify each change relative to Comanche 55. Here's a guide to some of the Apollo documentation relevant to those annotations:
Among documentation not actually referenced in the annotations, there is a short writeup about the reconstruction process in our software repository that may be helpful in understanding it from a different perspective. There's also a handy table that lists what the number of memory-words should be for each routine in Comanche 51, which could make a nice double-check; however, we've not performed that double-check ourselves.

Comments expected to have been present in the original source code are prefixed with a single '#' symbol, whereas comments added later are prefixed by "##" or "###". Report any errors noted by creating an issue report at the Virtual AGC Project's GitHub repository.

016689,000002:                                                                                                  ## Copyright:   Public domain.
016690,000003:                                                                                                  ## Filename:    R60,R62.agc
016691,000004:                                                                                                  ## Purpose:     A section of Comanche revision 051.
016692,000005:                                                                                                  ##              It is part of the reconstructed source code for the
016693,000006:                                                                                                  ##              original release of the flight software for the Command
016694,000007:                                                                                                  ##              Module's (CM) Apollo Guidance Computer (AGC) for Apollo 11.
016695,000008:                                                                                                  ##              The code has been recreated from a copy of Comanche 055. It
016696,000009:                                                                                                  ##              has been adapted such that the resulting bugger words
016697,000010:                                                                                                  ##              exactly match those specified for Comanche 51 in NASA drawing
016698,000011:                                                                                                  ##              2021153D, which gives relatively high confidence that the
016699,000012:                                                                                                  ##              reconstruction is correct.
016700,000013:                                                                                                  ## Reference:   pp. 390-398
016701,000014:                                                                                                  ## Assembler:   yaYUL
016702,000015:                                                                                                  ## Contact:     Ron Burkey <info@sandroid.org>.
016703,000016:                                                                                                  ## Website:     www.ibiblio.org/apollo/index.html
016704,000017:                                                                                                  ## Mod history: 2019-07-30 MAS  Created from Comanche 55.
016705,000018: 

Page 390

016707,000020: 34,2002                                           BANK     34                                    
016708,000021: 27,2000                                           SETLOC   MANUVER                               
016709,000022: 27,2000                                           BANK                                           
016710,000023: 
016711,000024: 27,2000     1146                                  EBANK=   TEMPR60                               
016712,000025: 
016713,000026: 27,2000                                           COUNT    27/R60                                
016714,000027: 
016715,000028:                                                                                                  #  R60CSM
016716,000029:                                                                                                  #  REV 13        CONFORMS TO GSOP CHAPTER FOUR REVISION LOGIC 09 JAN 18, 1968
016717,000030: 
016718,000031: 27,2000           04711        R60CSM             TC       MAKECADR                              
016719,000032: 27,2001           55146                           TS       TEMPR60                               
016720,000033: 
016721,000034:                                                                                                  #  INSERT PRIODSP CHECK WITH R22 (V06N49) WITH JENNINGS BRODEUR          
016722,000035: 
016723,000036: 27,2002           35012        REDOMANN           CAF      BIT6                                  
016724,000037: 27,2003           70101                           MASK     FLAGWRD5                              #  IS 3-AXIS FLAG SET
016725,000038: 27,2004           10000                           CCS      A                                     
016726,000039: 27,2005           12013                           TCF      TOBALL                                #  YES
016727,000040: 27,2006           06006                           TC       INTPRET                               
016728,000041: 27,2007           77624                           CALL                                           
016729,000042: 27,2010           56126                                    VECPOINT                              #  TO COMPUTE FINAL ANGLES
016730,000043: 27,2011           01156                           STORE    CPHI                                  #  STORE FINAL ANGLES - CPHI, CTHETA, CPSI
016731,000044: 27,2012           77776                           EXIT                                           
016732,000045: 
016733,000046: 27,2013           32125        TOBALL             CAF      V06N18                                
016734,000047: 27,2014           04662                           TC       BANKCALL                              
016735,000048: 27,2015           21132                           CADR     GOPERF2R                              #  DISPLAY PLEASE PERFORM AUTO MANEUVER
016736,000049: 27,2016           02114                           TC       R61TEST                               
016737,000050: 27,2017           02023                           TC       REDOMANC                              #  PROCEED
016738,000051: 27,2020           12052                           TCF      ENDMANU1                              #  ENTER I.E. FINISHED WITH R60
016739,000052: 
016740,000053: 27,2021           02056                           TC       CHKLINUS                              #  TO CHECK FOR PRIORITY DISPLAYS
016741,000054: 27,2022           05217                           TC       ENDOFJOB                              
016742,000055: 
016743,000056: 27,2023           35012        REDOMANC           CAF      BIT6                                  
016744,000057: 27,2024           70101                           MASK     FLAGWRD5                              #  IS 3-AXIS FLAG SET
016745,000058: 27,2025           10000                           CCS      A                                     
016746,000059: 27,2026           12034                           TCF      TOBALLC                               #  YES
016747,000060: 27,2027           06006                           TC       INTPRET                               
016748,000061: 27,2030           77624                           CALL                                           
016749,000062: 27,2031           56126                                    VECPOINT                              #  TO COMPUTE FINAL ANGLES
016750,000063: 27,2032           01156                           STORE    CPHI                                  #  STORE ANGLES
016751,000064: 27,2033           77776                           EXIT                                           
016752,000065: 
016753,000066: 27,2034           34371        TOBALLC            CAF      PRIO30                                #  IS MODE AUTO AND CTL GNC

Page 391

016755,000068: 27,2035           00006                           EXTEND                                         
016756,000069: 27,2036           06031                           RXOR     CHAN31                                
016757,000070: 27,2037           77707                           MASK     13,14,15                              
016758,000071: 27,2040           00006                           EXTEND                                         
016759,000072: 27,2041           12043                           BZF      +2                                    #  AUTO, NON-FLASH N18
016760,000073: 27,2042           12013                           TCF      TOBALL                                #  NOT AUTO
016761,000074: 
016762,000075: 27,2043           32125                           CAF      V06N18                                #  SET UP NON-FLASHING V06 N18
016763,000076: 27,2044           04662                           TC       BANKCALL                              
016764,000077: 27,2045           20676                           CADR     GODSPR                                
016765,000078: 27,2046           02056                           TC       CHKLINUS                              
016766,000079: 
016767,000080: 27,2047           04662        STARTMNV           TC       BANKCALL                              
016768,000081: 27,2050           17627                           CADR     GOMANUR                               
016769,000082: 27,2051           12013        ENDMANUV           TCF      TOBALL                                #  FINISHED MANEUVER
016770,000083: 
016771,000084: 27,2052           05560        ENDMANU1           TC       DOWNFLAG                              #  RESET 3-AXIS FLAG
016772,000085: 27,2053           00124                           ADRES    3AXISFLG                              #  BIT 6 FLAG 5
016773,000086: 27,2054           31146                           CAE      TEMPR60                               #                                        -
016774,000087: 27,2055           04704                           TC       BANKJUMP                              #                                        -
016775,000088: 
016776,000089: 27,2056           40100        CHKLINUS           CS       FLAGWRD4                              
016777,000090: 27,2057           75004                           MASK     BIT12                                 #  IS PRIORITY DISPLAY FLAG SET          -
016778,000091: 27,2060           10000                           CCS      A                                     #                                        -
016779,000092: 27,2061           00002                           TC       Q                                     #  NO - EXIT
016780,000093: 27,2062           30002                           CA       Q                                     
016781,000094: 27,2063           54156                           TS       MPAC       +2                         #  SAVE RETURN
016782,000095: 27,2064           46214                           CS       THREE                                 #  OBTAIN LOCATION FOR RESTART.
016783,000096: 27,2065           60133                           AD       BUF2                                  #  HOLDS Q OF LAST DISPALY
016784,000097: 27,2066           55053                           TS       TBASE1                                
016785,000098: 
016786,000099: 27,2067           05412                           TC       PHASCHNG                              
016787,000100: 27,2070           00071                           OCT      71                                    #  1.7SPOT FOR RELINUS
016788,000101: 
016789,000102: 27,2071           35011                           CAF      BIT7                                  
016790,000103: 27,2072           05526                           TC       LINUS                                 #  GO SET BITS FOR PRIORITY DISPLAY      -
016791,000104: 27,2073           00156                           TC       MPAC       +2                         
016792,000105: 
016793,000106: 27,2074           35013        RELINUS            CAF      BIT5                                  #  IS TRACK FLAG ON
016794,000107: 27,2075           70075                           MASK     FLAGWRD1                              
016795,000108: 27,2076           00006                           EXTEND                                         
016796,000109: 27,2077           12111                           BZF      GOREDO20                              #  NO
016797,000110: 
016798,000111: 27,2100           05546                           TC       UPFLAG                                
016799,000112: 27,2101           00077                           ADRES    PDSPFLAG                              #  R60 PRIODSP FLAG
016800,000113: 
016801,000114: 27,2102           05546                           TC       UPFLAG                                
016802,000115: 27,2103           00024                           ADRES    TARG1FLG                              #  FOR R52
016803,000116: 
016804,000117: 27,2104           35021                           CAF      ZERO                                  #  RESET TO ZERO, SINCE

Page 392

016806,000119: 27,2105           55303                           TS       OPTIND                                #  OPTIND WAS SET TO -1 BY V379
016807,000120: 
016808,000121: 27,2106           35066                           CAF      PRIO14                                #  RESTORE ORIGINAL PRIORITY
016809,000122: 27,2107           05210                           TC       PRIOCHNG                              
016810,000123: 
016811,000124: 27,2110           01053                           TC       TBASE1                                
016812,000125: 
016813,000126: 27,2111           05412        GOREDO20           TC       PHASCHNG                              
016814,000127: 27,2112           00111                           OCT      111                                   #  1.11 FOR PIKUP20
016815,000128: 
016816,000129: 27,2113           05217                           TC       ENDOFJOB                              
016817,000130: 
016818,000131: 27,2114           31011        R61TEST            CA       MODREG                                #  ARE WE IN P00.  IF YES THIS MUST BE
016819,000132: 27,2115           00006                           EXTEND                                         #        VERB49 OR VERB89 SO DO ENDEXT.
016820,000133: 27,2116           12052                           BZF      ENDMANU1                              #  RESET 3-AXIS & RUTURN.  USER DOES ENDEXT
016821,000134: 27,2117           30100                           CA       FLAGWRD4                              #  ARE WE IN R61 (P20)
016822,000135: 27,2120           75004                           MASK     BIT12                                 
016823,000136: 27,2121           00006                           EXTEND                                         
016824,000137: 27,2122           14106                           BZF      GOTOPOOH                              #  NO
016825,000138: 27,2123           04622                           TC       GOTOV56                               #  YES
016826,000139: 
016827,000140: 27,2124           20100        BIT14+7            OCT      20100                                 #                                        -
016828,000141: 27,2125           01422        V06N18             VN       0618                                  
016829,000142: 

Page 393

016831,000144:                                                                                                  #  PROGRAM DESCRIPTION - VECPOINT
016832,000145: 
016833,000146:                                                                                                  #  THIS INTERPRETIVE SUBROUTINE MAY BE USED TO POINT A SPACECRAFT AXIS IN A DESIRED DIRECTION.  THE AXIS
016834,000147:                                                                                                  #  TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN SUCCESSIVE LOCATIONS OF ERASABLE MEMORY
016835,000148:                                                                                                  #  BEGINNING WITH THE LOCATION CALLED SCAXIS.  THE COMPONENTS OF THIS VECTOR ARE GIVEN IN SPACECRAFT COORDINATES.
016836,000149:                                                                                                  #  THE DIRECTION IN WHICH THIS AXIS IS TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN
016837,000150:                                                                                                  #  SUCCESSIVE LOCATIONS OF ERASABLE MEMORY BEGINNING WITH THE ADDRESS CALLED POINTVSM.  THE COMPONENTS OF THIS
016838,000151:                                                                                                  #  VECTOR ARE GIVEN IN STABLE MEMBER COORDINATES.  WITH THIS INFORMATION VECPOINT COMPUTES A SET OF THREE GIMBAL
016839,000152:                                                                                                  #  ANGLES (2S COMPLEMENT) CORRESPONDING TO THE CROSS-PRODUCT ROTATION BETWEEN SCAXIS AND POINTVSM AND STORES THEM
016840,000153:                                                                                                  #  IN T(MPAC) BEFORE RETURNING TO THE CALLER.
016841,000154: 
016842,000155:                                                                                                  #  THIS ROTATION, HOWEVER, MAY BRING THE S/C INTO GIMBAL LOCK.  WHEN POINTING A VECTOR IN THE Y-Z PLANE,
016843,000156:                                                                                                  #  THE TRANSPONDER AXIS, OR THE AOT FOR THE LEM, THE PROGRAM WILL CORRECT THIS PROBLEM BY ROTATING THE CROSS-
016844,000157:                                                                                                  #  PRODUCT ATTITUDE ABOUT POINTVSM BY A FIXED AMOUNT SUFFICIENT TO ROTATE THE DESIRED S/C ATTITUDE OUT OF GIMBAL
016845,000158:                                                                                                  #  LOCK.  IF THE AXIS TO BE POINTED IS MORE THAN 40.6 DEGREES BUT LESS THAN 60.5 DEG FROM THE +X (OR -X) AXIS,
016846,000159:                                                                                                  #  THE ADDITIONAL ROTATION TO AVOID GIMAL LOCK IS 35 DEGREES.  IF THE AXIS IS MORE THAN 60.5 DEGEES FROM +X (OR -X)
016847,000160:                                                                                                  #  THE ADDITIONAL ROTATION IS 35 DEGREES.  THE GIMBAL ANGLES CORRESPONDING TO THIS ATTITUDE ARE THEN COMPUTED AND
016848,000161:                                                                                                  #  STORED AS 2S COMPLIMENT ANGLES IN T(MPAC) BEFORE RETURNING TO THE CALLER.
016849,000162: 
016850,000163:                                                                                                  #  WHEN POINTING THE X-AXIS, OR THE THRUST VECTOR, OR ANY VECTOR WITHIN 40.6 DEG OF THE X-AXIS, VECPOINT
016851,000164:                                                                                                  #  CANNOT CORRECT FOR A CROSS-PRODUCT ROTATION INTO GIMBAL LOCK.  IN THIS CASE A PLATFORM REALIGNMENT WOULD BE
016852,000165:                                                                                                  #  REQUIRED TO POINT THE VECTOR IN THE DESIRED DIRECTION.  AT PRESENT NO INDICATION IS GIVEN FOR THIS SITUATION
016853,000166:                                                                                                  #  EXCEPT THAT THE FINAL MIDDLE GIMBAL ANGLE IN MPAC +2 IS GREATER THAN 59 DEGREES.
016854,000167: 
016855,000168:                                                                                                  #  CALLING SEQUENCE -
016856,000169: 
016857,000170:                                                                                                  #        1)      LOAD SCAXIS, POINTVSM
016858,000171:                                                                                                  #        2)      CALL
016859,000172:                                                                                                  #                        VECPOINT
016860,000173: 
016861,000174:                                                                                                  #  RETURNS WITH
016862,000175: 
016863,000176:                                                                                                  #        1)      DESIRED OUTER GIMBAL ANGLE IN MPAC
016864,000177:                                                                                                  #        2)      DESIRED INNER GIMBAL ANGLE IN MPAC +1
016865,000178:                                                                                                  #        3)      DESIRED MIDDLE GIMBAL ANGLE IN MPAC +2
016866,000179: 
016867,000180:                                                                                                  #  ERASABLES USED -
016868,000181: 
016869,000182:                                                                                                  #        1)      SCAXIS          6
016870,000183:                                                                                                  #        2)      POINTVSM        6
016871,000184:                                                                                                  #        3)      MIS             18
016872,000185:                                                                                                  #        4)      DEL             18
016873,000186:                                                                                                  #        5)      COF             6
016874,000187:                                                                                                  #        6)      VECQTEMP        1
016875,000188:                                                                                                  #        7)      ALL OF VAC AREA 43
016876,000189: 
016877,000190:                                                                                                  #                        TOTAL   99
016878,000191: 
016879,000192: 27,2000                                           SETLOC   VECPT                                 
016880,000193: 27,2000                                           BANK                                           

Page 394

016882,000195: 27,2126  E6,1661                                  EBANK=   BCDU                                  
016883,000196: 
016884,000197: 27,2126                                           COUNT    27/VECPT                              
016885,000198: 
016886,000199: 27,2126           40020        VECPOINT           STQ      BOV                                   #  SAVE RETURN ADDRESS
016887,000200: 27,2127           03310                                    VECQTEMP                              
016888,000201: 27,2130           56131                                    VECLEAR                               #  AND CLEAR OVFIND
016889,000202: 27,2131           47164        VECLEAR            AXC,2    RTB                                   
016890,000203: 27,2132           03320                                    MIS                                   #  READ THE PRESENT CDU ANGLES AND
016891,000204: 27,2133           44376                                    READCDUK                              #  STORE THEM IN PD25, 26, 27
016892,000205: 27,2134           34032                           STCALL   25D                                   
016893,000206: 27,2135           44405                                    CDUTODCM                              #  S/C AXES TO STABLE MEMBER AXES (MIS)
016894,000207: 27,2136           61375                           VLOAD    VXM                                   
016895,000208: 27,2137           03357                                    POINTVSM                              #  RESOLVE THE POINTING DIRECTION VF INTO
016896,000209: 27,2140           03321                                    MIS                                   #  INITIAL S/C AXES (VF = POINTVSM)
016897,000210: 27,2141           77656                           UNIT                                           
016898,000211: 27,2142           00035                           STORE    28D                                   
016899,000212:                                                                                                  #  PD 28 29 30 31 32 33
016900,000213: 27,2143           53435                           VXV      UNIT                                  #  TAKE THE CROSS PRODUCT VF X VI
016901,000214: 27,2144           03351                                    SCAXIS                                #  WHERE VI = SCAXIS
016902,000215: 27,2145           57400                           BOV      VCOMP                                 
016903,000216: 27,2146           56256                                    PICKAXIS                              
016904,000217: 27,2147           17343                           STODL    COF                                   #  CHECK MAGNITUDE
016905,000218: 27,2150           00045                                    36D                                   #  OF CROSS PRODUCT
016906,000219: 27,2151           50025                           DSU      BMN                                   #  VECTOR, IF LESS
016907,000220: 27,2152           16327                                    DPB-14                                #  THAN B-14 ASSUME
016908,000221: 27,2153           56256                                    PICKAXIS                              #  UNIT OPERATION
016909,000222: 27,2154           50375                           VLOAD    DOT                                   #  INVALID.
016910,000223: 27,2155           03351                                    SCAXIS                                
016911,000224: 27,2156           00035                                    28D                                   
016912,000225: 27,2157           65552                           SL1      ARCCOS                                
016913,000226: 27,2160           77624        COMPMATX           CALL                                           #  NOW COMPUTE THE TRANSFORMATION FROM
016914,000227: 27,2161           44530                                    DELCOMP                               #  FINAL S/C AXES TO INITIAL S/C AXES MFI
016915,000228: 27,2162           75160                           AXC,1    AXC,2                                 
016916,000229: 27,2163           03320                                    MIS                                   #  COMPUTE THE TRANSFORMATION FROM FINAL
016917,000230: 27,2164           03425                                    DEL                                   #  S/C AXES TO STABLE MEMBER AXES
016918,000231: 27,2165           77624                           CALL                                           #  MFS = MIS MFI
016919,000232: 27,2166           44304                                    MXM3                                  #  (IN PD LIST)
016920,000233: 
016921,000234: 27,2167           51545                           DLOAD    ABS                                   
016922,000235: 27,2170           00007                                    6                                     #  MFS6 = SIN(CPSI)                      $2
016923,000236: 27,2171           50025                           DSU      BMN                                   
016924,000237: 27,2172           16314                                    SINGIMLC                              #  = SIN(59 DEGS)                        $2
016925,000238: 27,2173           56246                                    FINDGIMB                              #  /CPSI/ LESS THAN 59 DEGS
016926,000239:                                                                                                  #  I.E. DESIRED ATTITUDE NOT IN GIMBAL LOCK
016927,000240: 
016928,000241: 27,2174           51545                           DLOAD    ABS                                   #  CHECK TO SEE IF WE ARE POINTING
016929,000242: 27,2175           03351                                    SCAXIS                                #  THE THRUST AXIS
016930,000243: 27,2176           51025                           DSU      BPL                                   
016931,000244: 27,2177           16316                                    SINVEC1                               #  SIN 49.4 DEGS                         $2

Page 395

016933,000246: 27,2200           56246                                    FINDGIMB                              #  IF SO, WE ARE TRYING TO POINT IT INTO
016934,000247: 27,2201           77775                           VLOAD                                          #  GIMBAL LOCK, ABORT COULD GO HERE
016935,000248: 27,2202           77626                           STADR                                          
016936,000249: 27,2203           50442                           STOVL    MIS        +12D                       
016937,000250: 27,2204           77626                           STADR                                          #  STORE MFS (IN PD LIST) IN MIS
016938,000251: 27,2205           50450                           STOVL    MIS        +6                         
016939,000252: 27,2206           77626                           STADR                                          
016940,000253: 27,2207           50456                           STOVL    MIS                                   
016941,000254: 27,2210           03327                                    MIS        +6                         #  INNER GIMBAL AXIS IN FINAL S/C AXES
016942,000255: 27,2211           57444                           BPL      VCOMP                                 #  LOCATE THE IG AXIS DIRECTION CLOSEST TO
016943,000256: 27,2212           56213                                    IGSAMEX                               #  FINAL X S/C AXIS
016944,000257: 
016945,000258: 27,2213           50035        IGSAMEX            VXV      BMN                                   #  FIND THE SHORTEST WAY OF ROTATING THE 
016946,000259: 27,2214           03351                                    SCAXIS                                #  S/C OUT OF GIMBAL LOCK BY A ROTATION 
016947,000260: 27,2215           56222                                    U=SCAXIS                              #  ABOUT +- SCAXIS, I.E. IF  (IG (SGN MFS3)
016948,000261:                                                                                                  #  X SCAXIS . XF) LESS THAN 0, U = SCAXIS
016949,000262:                                                                                                  #  OTHERWISE U = -SCAXIS
016950,000263: 
016951,000264: 27,2216           57575                           VLOAD    VCOMP                                 
016952,000265: 27,2217           03351                                    SCAXIS                                
016953,000266: 27,2220           37343                           STCALL   COF                                   #  ROTATE ABOUT -SCAXIS
016954,000267: 27,2221           56225                                    CHEKAXIS                              
016955,000268: 27,2222           77775        U=SCAXIS           VLOAD                                          
016956,000269: 27,2223           03351                                    SCAXIS                                
016957,000270: 27,2224           03343                           STORE    COF                                   #  ROTATE ABOUT + SCAXIS
016958,000271: 27,2225           51545        CHEKAXIS           DLOAD    ABS                                   
016959,000272: 27,2226           03351                                    SCAXIS                                #  SEE IF WE ARE POINTING THE AOT
016960,000273: 27,2227           51025                           DSU      BPL                                   
016961,000274: 27,2230           16320                                    SINVEC2                               #  SIN 29.5 DEGS                         $2
016962,000275: 27,2231           56235                                    PICKANG1                              #  IF SO, ROTATE 50 DEGS ABOUT +- SCAXIS
016963,000276: 27,2232           52145                           DLOAD    GOTO                                  #  IF NOT, MUST BE POINTING THE TRANSPONDER
016964,000277: 27,2233           16324                                    VECANG2                               #  OR SOME VECTOR IN THE Y, OR Z PLANE
016965,000278: 27,2234           56237                                    COMPMFSN                              #  IN THIS CASE ROTATE 35 DEGS TO GET OUT
016966,000279:                                                                                                  #  OF GIMBAL LOCK (VECANG2 $360)
016967,000280: 27,2235           77745        PICKANG1           DLOAD                                          
016968,000281: 27,2236           16322                                    VECANG1                               #  = 50 DEGS                          $ 360
016969,000282: 27,2237           77624        COMPMFSN           CALL                                           
016970,000283: 27,2240           44530                                    DELCOMP                               #  COMPUTE THE ROTATION ABOUT SCAXIS TO
016971,000284: 27,2241           75160                           AXC,1    AXC,2                                 #  BRING MFS OUT OF GIMBAL LOCK
016972,000285: 27,2242           03320                                    MIS                                   
016973,000286: 27,2243           03425                                    DEL                                   
016974,000287: 27,2244           77624                           CALL                                           #  COMPUTE THE NEW TRANSFORMATION FROM
016975,000288: 27,2245           44304                                    MXM3                                  #  DESIRED S/C AXES TO STABLE MEMBER AXES
016976,000289:                                                                                                  #  WHICH WILL ALIGN VI WITH VF AND AVOID
016977,000290:                                                                                                  #  GIMBAL LOCK
016978,000291: 27,2246           45160        FINDGIMB           AXC,1    CALL                                  
016979,000292: 27,2247           00000                                    0                                     #  EXTRACT THE COMMANDED CDU ANGLES FROM
016980,000293: 27,2250           44655                                    DCMTOCDU                              #  THIS MATRIX
016981,000294: 27,2251           40234                           RTB      SETPD                                 
016982,000295: 27,2252           45552                                    V1STO2S                               #  CONVERT TO 2:S COMPLEMENT

Page 396

016984,000297: 27,2253           00001                                    0                                     
016985,000298: 27,2254           77650                           GOTO                                           
016986,000299: 27,2255           03310                                    VECQTEMP                              #  RETURN TO CALLER
016987,000300: 
016988,000301: 27,2256           50375        PICKAXIS           VLOAD    DOT                                   #  IF VF X VI = 0, FIND VF . VI
016989,000302: 27,2257           00035                                    28D                                   
016990,000303: 27,2260           03351                                    SCAXIS                                
016991,000304: 27,2261           72240                           BMN      TLOAD                                 
016992,000305: 27,2262           56266                                    ROT180                                
016993,000306: 27,2263           00032                                    25D                                   
016994,000307: 27,2264           77650                           GOTO                                           #  IF VF = VI, CDU DESIRED = PRESENT CDU
016995,000308: 27,2265           03310                                    VECQTEMP                              #  PRESENT CDU ANGLES
016996,000309: 
016997,000310: 27,2266           47375        ROT180             VLOAD    VXV                                   #  IF VF, VI ANTIPARALLEL, 180 DEG ROTATION
016998,000311: 27,2267           03327                                    MIS        +6                         #  IS REQUIRED.  Y STABLE MEMBER AXIS IN
016999,000312: 27,2270           15333                                    HIUNITX                               #  INITIAL S/C AXIS.
017000,000313: 27,2271           47256                           UNIT     VXV                                   #  FIND Y(SM) X X(I)
017001,000314: 27,2272           03351                                    SCAXIS                                #  FIND UNIT(VI X UNIT(Y(SM) X X(I)))
017002,000315: 27,2273           40056                           UNIT     BOV                                   #  I.E. PICK A VECTOR IN THE PLANE OF X(I),
017003,000316: 27,2274           56310                                    PICKX                                 #  Y(SM) PERPENDICULAR TO VI
017004,000317: 27,2275           17343                           STODL    COF                                   
017005,000318: 27,2276           00045                                    36D                                   #  CHECK MAGNITUDE
017006,000319: 27,2277           50025                           DSU      BMN                                   #  OF THIS VECTOR.
017007,000320: 27,2300           16327                                    DPB-14                                #  IF LESS THAN B-14,
017008,000321: 27,2301           56310                                    PICKX                                 #  PICK X-AXIS.
017009,000322: 27,2302           77775                           VLOAD                                          
017010,000323: 27,2303           03343                                    COF                                   
017011,000324: 27,2304           17343        XROT               STODL    COF                                   
017012,000325: 27,2305           15333                                    HIDPHALF                              
017013,000326: 27,2306           77650                           GOTO                                           
017014,000327: 27,2307           56160                                    COMPMATX                              
017015,000328: 27,2310           52175        PICKX              VLOAD    GOTO                                  #  PICK THE XAXIS IN THIS CASE
017016,000329: 27,2311           15333                                    HIUNITX                               
017017,000330: 27,2312           56304                                    XROT                                  
017018,000331: 35,2000                                           BANK     35                                    
017019,000332: 27,2000                                           SETLOC   MANUVER1                              
017020,000333: 27,2000                                           BANK                                           
017021,000334: 
017022,000335: 27,2313           15555 35172  SINGIMLC           2DEC     .4285836003                            #  = SIN(59)                             $2
017023,000336: 
017024,000337: 27,2315           14113 36326  SINVEC1            2DEC     .3796356537                            #  = SIN(49.4)                           $2
017025,000338: 
017026,000339: 27,2317           07701 35703  SINVEC2            2DEC     .2462117800                            #  = SIN(29.5)                           $2
017027,000340: 
017028,000341: 27,2321           04343 21616  VECANG1            2DEC     .1388888889                            #  = 50 DEGREES                        $360
017029,000342: 
017030,000343: 27,2323           03070 34344  VECANG2            2DEC     .09722222222                            #  = 35 DEGREES                        $360
017031,000344: 
017032,000345: 
017033,000346: 27,2325           00000        1BITDP             OCT      0                                     #  KEEP THIS BEFORE DPB(-14)      *********
017034,000347: 27,2326           00001        DPB-14             OCT      00001                                 

Page 397

017036,000349: 27,2327           00000                           OCT      00000                                 
017037,000350: 34,2002                                           BANK     34                                    
017038,000351: 27,2000                                           SETLOC   MANUVER                               
017039,000352: 27,2000                                           BANK                                           
017040,000353: 

Page 398

017042,000355:                                                                                                  #  ROUTINE FOR INITIATING AUTOMATIC MANEUVER VIA KEYBOARD (V49)
017043,000356: 
017044,000357: 27,2330     1155                                  EBANK=   CPHI                                  
017045,000358: 
017046,000359: 27,2330                                           COUNT    27/R62                                
017047,000360: 
017048,000361: 27,2330           35052        R62DISP            CAF      V06N22                                #  DISPLAY COMMAND ICDUS CPHI, CTHETA, CPHI
017049,000362: 27,2331           04662                           TC       BANKCALL                              
017050,000363: 27,2332           20720                           CADR     GOFLASH                               
017051,000364: 27,2333           15534                           TCF      ENDEXT                                
017052,000365: 27,2334           12336                           TCF      GOMOVE                                #  PROCEED
017053,000366: 27,2335           12330                           TCF      R62DISP                               #  ENTER
017054,000367: 
017055,000368:                                                                                                  #  ASTRONAUT MAY LOAD NEW ICDUS AT THIS
017056,000369:                                                                                                  #  POINT
017057,000370: 27,2336           05546        GOMOVE             TC       UPFLAG                                #  SET 3-AXIS FLAG
017058,000371: 27,2337           00124                           ADRES    3AXISFLG                              #  BIT 6  FLAG 5
017059,000372: 
017060,000373: 27,2340           04662                           TC       BANKCALL                              
017061,000374: 27,2341           56000                           CADR     R60CSM                                
017062,000375: 27,2342           15534                           TCF      ENDEXT                                
017063,000376: 

End of include-file R60,R62.agc.  Parent file is MAIN.agc