Source Code

These source-code files were derived originally from the scan from MIT's Dibner Institute's now-discontinued website titled "History of Recent Science and Technology", which in turn was originally created by Gary Neff, though his high-quality scans were unfortunately reduced in legibility when presented online. The markings on the front of the printout imply that it was the original AGC developer Norm Brodeur's copy. A scan by Ron Burkey has superceded it, made from a more-legible copy from the collection of original AGC developer Fred Martin. The source code was transcribed from those images by Ron Burkey. 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:

	ASSEMBLE REVISION 249 OF AGC PROGRAM COLOSSUS BY NASA 2021111-041
	20'35 OCT. 28,1968
Note that the date is the date of the printout, not the date of the program revision.

063939,000002:                                                                                                  ## Copyright:   Public domain.
063940,000003:                                                                                                  ## Filename:    RT8_OP_CODES.agc
063941,000004:                                                                                                  ## Purpose:     Part of the source code for Colossus, build 249.
063942,000005:                                                                                                  ##              It is part of the source code for the Command Module's (CM)
063943,000006:                                                                                                  ##              Apollo Guidance Computer (AGC), possibly for Apollo 8 and 9.
063944,000007:                                                                                                  ## Assembler:   yaYUL
063945,000008:                                                                                                  ## Reference:   Starts on p. 1498 of 1701.pdf.
063946,000009:                                                                                                  ## Contact:     Ron Burkey <info@sandroid.org>.
063947,000010:                                                                                                  ## Website:     www.ibiblio.org/apollo.
063948,000011:                                                                                                  ## Mod history: 08/30/04 RSB.   Adapted from corresponding Luminary131 file.
063949,000012:                                                                                                  ##
063950,000013:                                                                                                  ## The contents of the "Colossus249" files, in general, are transcribed 
063951,000014:                                                                                                  ## from a scanned document obtained from MIT's website,
063952,000015:                                                                                                  ## http://hrst.mit.edu/hrs/apollo/public/archive/1701.pdf.  Notations on this
063953,000016:                                                                                                  ## document read, in part:
063954,000017:                                                                                                  ##
063955,000018:                                                                                                  ##      Assemble revision 249 of AGC program Colossus by NASA
063956,000019:                                                                                                  ##      2021111-041.  October 28, 1968.  
063957,000020:                                                                                                  ##
063958,000021:                                                                                                  ##      This AGC program shall also be referred to as
063959,000022:                                                                                                  ##                              Colossus 1A
063960,000023:                                                                                                  ##
063961,000024:                                                                                                  ##      Prepared by
063962,000025:                                                                                                  ##                      Massachusetts Institute of Technology
063963,000026:                                                                                                  ##                      75 Cambridge Parkway
063964,000027:                                                                                                  ##                      Cambridge, Massachusetts
063965,000028:                                                                                                  ##      under NASA contract NAS 9-4065.
063966,000029:                                                                                                  ##
063967,000030:                                                                                                  ## Refer directly to the online document mentioned above for further information.
063968,000031:                                                                                                  ## Please report any errors (relative to 1701.pdf) to info@sandroid.org.
063969,000032:                                                                                                  ##
063970,000033:                                                                                                  ## In some cases, where the source code for Luminary 131 overlaps that of 
063971,000034:                                                                                                  ## Colossus 249, this code is instead copied from the corresponding Luminary 131
063972,000035:                                                                                                  ## source file, and then is proofed to incorporate any changes.
063973,000036: 

Page 1498

063975,000038: 22,3505                                           BANK     22                                    
063976,000039: 22,2000                                           SETLOC   RTBCODES                              
063977,000040: 22,2000                                           BANK                                           
063978,000041: 
063979,000042: 22,3505  E5,1713                                  EBANK=   XNB                                   
063980,000043: 22,3505                                           COUNT*   $$/RTB                                
063981,000044: 
063982,000045:                                                                                                  #  LOAD TIME2, TIME1 INTO MPAC:
063983,000046: 
063984,000047: 22,3505           00006        LOADTIME           EXTEND                                         
063985,000048: 22,3506           30025                           DCA      TIME2                                 
063986,000049: 22,3507           16024                           TCF      SLOAD2                                
063987,000050: 
063988,000051:                                                                                                  #  CONVERT THE SINGLE PRECISION 2'S COMPLEMENT NUMBER ARRIVING IN MPAC (SCALED IN HALF-REVOLUTIONS) TO A
063989,000052:                                                                                                  #  DP 1'S COMPLEMENT NUMBER SCALED IN REVOLUTIONS.
063990,000053: 
063991,000054: 22,3510           10154        CDULOGIC           CCS      MPAC                                  
063992,000055: 22,3511           34714                           CAF      ZERO                                  
063993,000056: 22,3512           13515                           TCF      +3                                    
063994,000057: 22,3513           13514                           NOOP                                           
063995,000058: 22,3514           44675                           CS       HALF                                  
063996,000059: 
063997,000060: 22,3515           54155                           TS       MPAC       +1                         
063998,000061: 22,3516           34714                           CAF      ZERO                                  
063999,000062: 22,3517           56154                           XCH      MPAC                                  
064000,000063: 22,3520           00006                           EXTEND                                         
064001,000064: 22,3521           74675                           MP       HALF                                  
064002,000065: 22,3522           20155                           DAS      MPAC                                  
064003,000066: 22,3523           16030                           TCF      DANZIG                                #  MODE IS ALREADY AT DOUBLE-PRECISION
064004,000067: 
064005,000068:                                                                                                  #  READ THE PIPS INTO MPAC WITHOUT CHANGING THEM:
064006,000069: 
064007,000070: 22,3524           00004        READPIPS           INHINT                                         
064008,000071: 22,3525           30037                           CA       PIPAX                                 
064009,000072: 22,3526           54154                           TS       MPAC                                  
064010,000073: 22,3527           30040                           CA       PIPAY                                 
064011,000074: 22,3530           54157                           TS       MPAC       +3                         
064012,000075: 22,3531           30041                           CA       PIPAZ                                 
064013,000076: 22,3532           00003                           RELINT                                         
064014,000077: 22,3533           54161                           TS       MPAC       +5                         
064015,000078: 
064016,000079: 22,3534           34714                           CAF      ZERO                                  
064017,000080: 22,3535           54155                           TS       MPAC       +1                         
064018,000081: 22,3536           54160                           TS       MPAC       +4                         
064019,000082: 22,3537           54162                           TS       MPAC       +6                         
064020,000083: 
064021,000084: 22,3540           16470        VECMODE            TCF      VMODE                                 
064022,000085: 
064023,000086:                                                                                                  #  FORCE TP SIGN AGREEMENT IN MPAC:
064024,000087: 
064025,000088: 22,3541           07226        SGNAGREE           TC       TPAGREE                               

Page 1499

064027,000090: 22,3542           16030                           TCF      DANZIG                                
064028,000091: 
064029,000092:                                                                                                  #  CONVERT THE DP 1'S COMPLEMENT ANGLE SCALED IN REVOLUTIONS TO A SINGLE PRECISION 2'S COMPLEMENT ANGLE
064030,000093:                                                                                                  #  SCALED IN HALF-REVOLUTIONS.
064031,000094: 
064032,000095: 22,3543           03573        1STO2S             TC       1TO2SUB                               
064033,000096: 22,3544           34714                           CAF      ZERO                                  
064034,000097: 22,3545           54155                           TS       MPAC       +1                         
064035,000098: 22,3546           16027                           TCF      NEWMODE                               
064036,000099: 
064037,000100:                                                                                                  #  DO 1STO2S ON A VECTOR OF ANGLES:
064038,000101: 
064039,000102: 22,3547           03573        V1STO2S            TC       1TO2SUB                               #  ANSWER ARRIVES IN A AND MPAC.
064040,000103: 
064041,000104: 22,3550           52162                           DXCH     MPAC       +5                         
064042,000105: 22,3551           52155                           DXCH     MPAC                                  
064043,000106: 22,3552           03573                           TC       1TO2SUB                               
064044,000107: 22,3553           54156                           TS       MPAC       +2                         
064045,000108: 
064046,000109: 22,3554           52160                           DXCH     MPAC       +3                         
064047,000110: 22,3555           52155                           DXCH     MPAC                                  
064048,000111: 22,3556           03573                           TC       1TO2SUB                               
064049,000112: 22,3557           54155                           TS       MPAC       +1                         
064050,000113: 
064051,000114: 22,3560           30161                           CA       MPAC       +5                         
064052,000115: 22,3561           54154                           TS       MPAC                                  
064053,000116: 
064054,000117: 22,3562           34712        TPMODE             CAF      ONE                                   #  MODE IS TP.
064055,000118: 22,3563           16027                           TCF      NEWMODE                               
064056,000119: 
064057,000120:                                                                                                  #  V1STO2S FOR 2 COMPONENT VECTOR. USED BY RR.
064058,000121: 
064059,000122: 22,3564           03573        2V1STO2S           TC       1TO2SUB                               
064060,000123: 22,3565           52160                           DXCH     MPAC       +3                         
064061,000124: 22,3566           52155                           DXCH     MPAC                                  
064062,000125: 22,3567           03573                           TC       1TO2SUB                               
064063,000126: 22,3570           54001                           TS       L                                     
064064,000127: 22,3571           30157                           CA       MPAC       +3                         
064065,000128: 22,3572           16024                           TCF      SLOAD2                                
064066,000129: 
064067,000130:                                                                                                  #  SUBROUTINE TO DO DOUBLING AND 1'S TO 2'S CONVERSION:
064068,000131: 
064069,000132: 22,3573           52155        1TO2SUB            DXCH     MPAC                                  #  FINAL MPAC +1 UNSPECIFIED.
064070,000133: 22,3574           20001                           DDOUBL                                         
064071,000134: 22,3575           10000                           CCS      A                                     
064072,000135: 22,3576           64712                           AD       ONE                                   
064073,000136: 22,3577           13601                           TCF      +2                                    
064074,000137: 22,3600           40000                           COM                                            #  THIS WAS REVERSE OF MSU.
064075,000138: 
064076,000139: 22,3601           54154                           TS       MPAC                                  #  AND SKIP ON OVERFLOW.

Page 1500

064078,000141: 22,3602           00002                           TC       Q                                     
064079,000142: 
064080,000143: 22,3603           50000                           INDEX    A                                     #  OVERFLOW UNCORRECT AND IN MSU.
064081,000144: 22,3604           34673                           CAF      LIMITS                                
064082,000145: 22,3605           26154                           ADS      MPAC                                  
064083,000146: 22,3606           00002                           TC       Q                                     
064084,000147: 

Page 1501

064086,000149:                                                                                                  #  SUBROUTINE TO INCREMENT CDUS
064087,000150: 
064088,000151: 22,3607           33622        INCRCDUS           CAF      LOCTHETA                              
064089,000152: 22,3610           54130                           TS       BUF                                   #  PLACE ADRES(THETA) IN BUF.
064090,000153: 22,3611           30154                           CAE      MPAC                                  #  INCREMENT IN 1'S COMPL.
064091,000154: 22,3612           03623                           TC       CDUINC                                
064092,000155: 
064093,000156: 22,3613           24130                           INCR     BUF                                   
064094,000157: 22,3614           30157                           CAE      MPAC       +3                         
064095,000158: 22,3615           03623                           TC       CDUINC                                
064096,000159: 
064097,000160: 22,3616           24130                           INCR     BUF                                   
064098,000161: 22,3617           30161                           CAE      MPAC       +5                         
064099,000162: 22,3620           03623                           TC       CDUINC                                
064100,000163: 
064101,000164: 22,3621           13540                           TCF      VECMODE                               
064102,000165: 
064103,000166: 22,3622           01155        LOCTHETA           ADRES    THETAD                                
064104,000167: 
064105,000168:                                                                                                  #  THE FOLLOWING ROUTINE INCREMENTS IN 2'S COMPLEMENT THE REGISTER WHOSE ADDRESS IS IN BUF BY THE 1'S COMPL.
064106,000169:                                                                                                  #  QUANTITY FOUND IN TEM2.  THIS MAY BE USED TO INCRMENT DESIRED IMU AND OPTICS CDU ANGLES OR ANY OTHER 2'S COMPL.
064107,000170:                                                                                                  #  (+0 UNEQUAL TO -0) QUANTITY.  MAY BE CALLED BY BANKCALL/SWCALL.
064108,000171: 
064109,000172: 22,3623           54142        CDUINC             TS       TEM2                                  #  1'S COMPL. QUANT. ARRIVES IN ACC.  STORE IT
064110,000173: 22,3624           50130                           INDEX    BUF                                   
064111,000174: 22,3625           10000                           CCS      0                                     #  CHANGE 2'S COMPLE. ANGEL (IN BUF) INTO 1'S
064112,000175: 22,3626           64712                           AD       ONE                                   
064113,000176: 22,3627           13633                           TCF      +4                                    
064114,000177: 22,3630           64712                           AD       ONE                                   
064115,000178: 22,3631           64712                           AD       ONE                                   #  OVEFLOW HERE IF 2'S COMPL. IS 180 DEG.
064116,000179: 22,3632           40000                           COM                                            
064117,000180: 
064118,000181: 22,3633           60142                           AD       TEM2                                  #  SULT MOVES FROM 2ND TO 3D QUAD. (OR BACK)
064119,000182: 22,3634           10000                           CCS      A                                     #  BACK TO 2'S COMPL.
064120,000183: 22,3635           64712                           AD       ONE                                   
064121,000184: 22,3636           13640                           TCF      +2                                    
064122,000185: 22,3637           40000                           COM                                            
064123,000186: 22,3640           54142                           TS       TEM2                                  #  STORE 14-BIT QUANTITY WITH PRESENT SIGN
064124,000187: 22,3641           13645                           TCF      +4                                    
064125,000188: 22,3642           50000                           INDEX    A                                     #  SIGN.
064126,000189: 22,3643           34673                           CAF      LIMITS                                #  FIX IT, BY ADDING IN 37777 OR 40000
064127,000190: 22,3644           60142                           AD       TEM2                                  
064128,000191: 
064129,000192: 22,3645           50130                           INDEX    BUF                                   
064130,000193: 22,3646           54000                           TS       0                                     #  STORE NEW ANGLE IN 2'S COMPLEMENT.
064131,000194: 22,3647           00002                           TC       Q                                     
064132,000195: 

Page 1502

064134,000197:                                                                                                  #  RTB TO TORQUE GYROS, EXCEPT FOR THE CALL TO IMUSTALL.  ECADR OF COMMANDS ARRIVES IN X1.
064135,000198: 
064136,000199: 22,3650           50120        PULSEIMU           INDEX    FIXLOC                                #  ADDRESS OF GYRO COMMANDS SHOULD BE IN X1
064137,000200: 22,3651           30046                           CA       X1                                    
064138,000201: 22,3652           04555                           TC       BANKCALL                              
064139,000202: 22,3653           17125                           CADR     IMUPULSE                              
064140,000203: 22,3654           16030                           TCF      DANZIG                                
064141,000204: 

Page 1503

064143,000206:                                                                                                  #  EACH ROUTINE TAKES A 3X3 MATRIX STORED IN DOUBLE PRECISION IN A FIXED AREA OF ERASABLE MEMORY AND REPLACES IT
064144,000207:                                                                                                  #  WITH THE TRANSPOSE MATRIX.  TRANSP1 USES LOCATIONS XNB+0,+1 THROUGH XNB+16D,+17D AND TRANSP2 USES LOCATIONS
064145,000208:                                                                                                  #  XNB1+0,+1 THROUGH XNB1+16D,+17D.  EACH MATRIX IS STORED BY ROWS.
064146,000209: 
064147,000210: 22,3655           02713        XNBEB              ECADR    XNB                                   
064148,000211: 22,3656           02554        XNB1EB             ECADR    XNB1                                  
064149,000212: 
064150,000213: 22,3657  E5,1713                                  EBANK=   XNB                                   
064151,000214: 
064152,000215: 22,3657           33655        TRANSP1            CAF      XNBEB                                 
064153,000216: 22,3660           54003                           TS       EBANK                                 
064154,000217: 22,3661           53716                           DXCH     XNB        +2                         
064155,000218: 22,3662           53722                           DXCH     XNB        +6                         
064156,000219: 22,3663           53716                           DXCH     XNB        +2                         
064157,000220: 
064158,000221: 22,3664           53720                           DXCH     XNB        +4                         
064159,000222: 22,3665           53730                           DXCH     XNB        +12D                       
064160,000223: 22,3666           53720                           DXCH     XNB        +4                         
064161,000224: 
064162,000225: 22,3667           53726                           DXCH     XNB        +10D                       
064163,000226: 22,3670           53732                           DXCH     XNB        +14D                       
064164,000227: 22,3671           53726                           DXCH     XNB        +10D                       
064165,000228: 22,3672           16030                           TCF      DANZIG                                
064166,000229: 22,3673  E5,1554                                  EBANK=   XNB1                                  
064167,000230: 
064168,000231: 22,3673           33656        TRANSP2            CAF      XNB1EB                                
064169,000232: 22,3674           54003                           TS       EBANK                                 
064170,000233: 22,3675           53557                           DXCH     XNB1       +2                         
064171,000234: 22,3676           53563                           DXCH     XNB1       +6                         
064172,000235: 22,3677           53557                           DXCH     XNB1       +2                         
064173,000236: 
064174,000237: 22,3700           53561                           DXCH     XNB1       +4                         
064175,000238: 22,3701           53571                           DXCH     XNB1       +12D                       
064176,000239: 22,3702           53561                           DXCH     XNB1       +4                         
064177,000240: 
064178,000241: 22,3703           53567                           DXCH     XNB1       +10D                       
064179,000242: 22,3704           53573                           DXCH     XNB1       +14D                       
064180,000243: 22,3705           53567                           DXCH     XNB1       +10D                       
064181,000244: 22,3706           16030                           TCF      DANZIG                                
064182,000245: 

Page 1504

064184,000247:                                                                                                  #  THE SUBROUTINE SIGNMPAC SETS C(MPAC, MPAC +1) TO SIGN(MPAC).
064185,000248:                                                                                                  #  FOR THIS, ONLY THE CONTENTS OF MPAC ARE EXAMINED.  ALSO +0 YIELDS POSMAX AND -0 YIELDS NEGMAX.
064186,000249: 
064187,000250:                                                                                                  #  ENTRY MAY BE BY EITHER OF THE FOLLOWING:
064188,000251:                                                                                                  #        1.      LIMIT THE SIZE OF MPAC ON INTERPRETIVE OVERFLOW:
064189,000252:                                                                                                  #                ENTRY:          BOVB
064190,000253:                                                                                                  #                                        SIGNMPAC
064191,000254:                                                                                                  #        2.      GENERATE IN MPAC THE SIGNUM FUNCTION OF MPAC:
064192,000255:                                                                                                  #                ENTRY:          RTB
064193,000256:                                                                                                  #                                        SIGNMPAC
064194,000257:                                                                                                  #  IN EITHER CASE, RETURN IS TO TEH NEXT INTERPRETIVE INSTRUCTION IN THE CALLING SEQUENCE.
064195,000258: 
064196,000259: 22,3707           00006        SIGNMPAC           EXTEND                                         
064197,000260: 22,3710           34672                           DCA      DPOSMAX                               
064198,000261: 22,3711           52155                           DXCH     MPAC                                  
064199,000262: 22,3712           10000                           CCS      A                                     
064200,000263: 22,3713           34714        DPMODE             CAF      ZERO                                  #  SETS MPAC +2 TO ZERO IN THE PROCESS
064201,000264: 22,3714           16026                           TCF      SLOAD2     +2                         
064202,000265: 22,3715           13716                           TCF      +1                                    
064203,000266: 22,3716           00006                           EXTEND                                         
064204,000267: 22,3717           44672                           DCS      DPOSMAX                               
064205,000268: 22,3720           16024                           TCF      SLOAD2                                
064206,000269: 
064207,000270:                                                                                                  #  RTB OP CODE NORMUNIT IS LIKE INTERPRETIVE INSTRUCTION UNIT, EXCEPT THAT IT CAN BE DEPENDED ON NOT TO BLOW
064208,000271:                                                                                                  #  UP WHEN THE VECTOR BEING UNITIZED IS VERY SAMLL -- IT WILL BLOW UP WHEN ALL COMPONENT ARE ZERO.  IF NORMUNIT
064209,000272:                                                                                                  #  IS USED AND THE UPPER ORDER HALVES OF ALL COMPONENTS ARE ERO, THE MAGNITUDE RETURNS IN 36D WILL BE TOO LARGE
064210,000273:                                                                                                  #  BY A FACTOR OF 2(13) AND THE SQURED MAGNITUDE RETURNED ATE 34D WILL BE TOO BIG BY A FACTOR OF 2(26).
064211,000274: 
064212,000275: 22,3721           34712        NORMUNX1           CAF      ONE                                   
064213,000276: 22,3722           13724                           TCF      NORMUNIT   +1                         
064214,000277: 22,3723           34714        NORMUNIT           CAF      ZERO                                  
064215,000278: 22,3724           60120                           AD       FIXLOC                                
064216,000279: 22,3725           54156                           TS       MPAC       +2                         
064217,000280: 22,3726           04555                           TC       BANKCALL                              #  GET SIGN AGREEMENT IN ALL COMPONENTS
064218,000281: 22,3727           01010                           CADR     VECAGREE                              
064219,000282: 22,3730           10154                           CCS      MPAC                                  
064220,000283: 22,3731           13765                           TCF      NOSHIFT                               
064221,000284: 22,3732           13734                           TCF      +2                                    
064222,000285: 22,3733           13765                           TCF      NOSHIFT                               
064223,000286: 22,3734           10157                           CCS      MPAC       +3                         
064224,000287: 22,3735           13765                           TCF      NOSHIFT                               
064225,000288: 22,3736           13740                           TCF      +2                                    
064226,000289: 22,3737           13765                           TCF      NOSHIFT                               
064227,000290: 22,3740           10161                           CCS      MPAC       +5                         
064228,000291: 22,3741           13765                           TCF      NOSHIFT                               
064229,000292: 22,3742           13744                           TCF      +2                                    
064230,000293: 22,3743           13765                           TCF      NOSHIFT                               

Page 1505

064232,000295: 22,3744           30155                           CA       MPAC       +1                         #  SHIFT ALL COMPONENTS LEFT 13
064233,000296: 22,3745           00006                           EXTEND                                         
064234,000297: 22,3746           74675                           MP       BIT14                                 
064235,000298: 22,3747           20155                           DAS      MPAC                                  #  DAS GAINS A LITTLE ACCURACY
064236,000299: 22,3750           30160                           CA       MPAC       +4                         
064237,000300: 22,3751           00006                           EXTEND                                         
064238,000301: 22,3752           74675                           MP       BIT14                                 
064239,000302: 22,3753           20160                           DAS      MPAC       +3                         
064240,000303: 22,3754           30162                           CA       MPAC       +6                         
064241,000304: 22,3755           00006                           EXTEND                                         
064242,000305: 22,3756           74675                           MP       BIT14                                 
064243,000306: 22,3757           20162                           DAS      MPAC       +5                         
064244,000307: 22,3760           34720                           CAF      THIRTEEN                              
064245,000308: 22,3761           50156                           INDEX    MPAC       +2                         
064246,000309: 22,3762           54045                           TS       37D                                   
064247,000310: 22,3763           04574        OFFTUNIT           TC       POSTJUMP                              
064248,000311: 22,3764           01024                           CADR     UNIT       +1                         #  SKIP THE "TC VECAGREE" DONE AT UNIT
064249,000312: 
064250,000313: 22,3765           34714        NOSHIFT            CAF      ZERO                                  
064251,000314: 22,3766           13761                           TCF      OFFTUNIT   -2                         
064252,000315: 
064253,000316:                                                                                                  #  RTB VECSGNAG ... FORCES SIGN AGREEMENT OF VECTOR IN MPAC.
064254,000317: 
064255,000318: 22,3767           04555        VECSGNAG           TC       BANKCALL                              
064256,000319: 22,3770           01010                           CADR     VECAGREE                              
064257,000320: 22,3771           06030                           TC       DANZIG                                
064258,000321: 
064259,000322:                                                                                                  #  *** END OF SATRAP  .007 ***
064260,000323: 
064261,000324: 
064262,000325: 
064263,000326: 

End of include-file RT8_OP_CODES.agc.  Parent file is MAIN.agc