Source Code

These source-code files were derived from scans of the Colossus 237 (Apollo 8 Command Module) program listing from the private collection of original AGC developer Fred Martin. Scanning was by Ron Burkey. Pre-existing Colossus 249 (Apollo 9 CM) source files were used as a template, and changes between Colossus 249 and Colossus 237 were manually transcribed by a team of volunteers. Note that the page images presented online are of reduced quality, and that additional images are available. Report any conversion errors or legibility problems in page images to info@sandroid.org. Notations on the program listing read, in part:

	GAP: ASSEMBLE REVISION 237 OF AGC PROGRAM COLOSSUS 
	BY NASA 2021111-031  1:17 AUG. 24, 1968
Note that the date is the date of the printout, not the date of the program revision.

017833,000002:                                                                                                  ## Copyright:   Public domain.
017834,000003:                                                                                                  ## Filename:    KALCMANU_STEERING.agc
017835,000004:                                                                                                  ## Purpose:     Part of the source code for Colossus build 237.  
017836,000005:                                                                                                  ##              This is for the Command Module's (CM) Apollo Guidance
017837,000006:                                                                                                  ##              Computer (AGC), for Apollo 8.
017838,000007:                                                                                                  ## Assembler:   yaYUL
017839,000008:                                                                                                  ## Contact:     Onno Hommes <ohommes@alumni.cmu.edu>
017840,000009:                                                                                                  ## Website:     www.ibiblio.org/apollo/index.html
017841,000010:                                                                                                  ## Page Scans:  www.ibiblio.org/apollo/ScansForConversion/Colossus237/
017842,000011:                                                                                                  ## Mod history: 2010-06-01 OH   Adapted from corresponding Colossus 249 file.
017843,000012:                                                                                                  ##              2010-12-04 JL   Remove Colossus 249 header comments. Change 
017844,000013:                                                                                                  ##                              to double-hash page numbers.
017845,000014:                                                                                                  ##              2011-01-27 JL   Minor fixes.
017846,000015:                                                                                                  ##              2016-08-14 RSB  Added SBANKs for addressing discrepancies.
017847,000016:                                                                                                  ##              2016-12-30 RSB  Proofed comment text using octopus/ProoferComments,
017848,000017:                                                                                                  ##                              and corrected errors found.
017849,000018:                                                                                                  ##              2017-01-28 RSB  WTIH -> WITH.
017850,000019: 

Page 405

017852,000021:                                                                                                  #  GENERATION OF STEERING COMMANDS FOR DIGITAL AUTOPILOT FREE FALL MANEUVERS
017853,000022: 
017854,000023:                                                                                                  #  NEW COMMANDS WILL BE GENERATED EVERY ONE SECOND DURING THE MANEUVER
017855,000024: 
017856,000025: 15,2000                                           BANK     15                                    
017857,000026: 
017858,000027: 22,2000                                           SETLOC   KALCMON1                              
017859,000028: 22,2000                                           BANK                                           
017860,000029: 

2016-08-14 RSB Added SBANK for addressing discrepancies.

017862,000031: 22,3027  40,2000                                  SBANK=   PINSUPER                              
017863,000032: 22,3027  E6,1661                                  EBANK=   BCDU                                  
017864,000033: 
017865,000034: 22,3027                                           COUNT    22/KALC                               
017866,000035: 
017867,000036: 22,3027           41332        NEWDELHI           CS       HOLDFLAG                              #  SEE IF MANEUVER HAS BEEN INTERRUPTED
017868,000037: 22,3030           00006                           EXTEND                                         #  BY ASTRONAUT
017869,000038: 22,3031           62725                           BZMF     NOGO       -2                         #  IF SO, TERMINATE KALCMANU
017870,000039: 22,3032           06006        NEWANGL            TC       INTPRET                               
017871,000040: 22,3033           75160                           AXC,1    AXC,2                                 
017872,000041: 22,3034           03320                                    MIS                                   #  COMPUTE THE NEW MATRIX FROM S/C TO
017873,000042: 22,3035           03425                                    DEL                                   #  STABLE MEMBER AXES
017874,000043: 22,3036           77624                           CALL                                           
017875,000044: 22,3037           44304                                    MXM3                                  
017876,000045: 22,3040           45575                           VLOAD    STADR                                 
017877,000046: 22,3041           50442                           STOVL    MIS        +12D                       #  CALCULATE NEW DESIRED CDU ANGLES
017878,000047: 22,3042           77626                           STADR                                          
017879,000048: 22,3043           50450                           STOVL    MIS        +6D                        
017880,000049: 22,3044           77626                           STADR                                          
017881,000050: 22,3045           74456                           STORE    MIS                                   
017882,000051: 22,3046           45160                           AXC,1    CALL                                  
017883,000052: 22,3047           03320                                    MIS                                   
017884,000053: 22,3050           44655                                    DCMTOCDU                              #  PICK UP THE NEW CDU ANGLES FROM MATRIX
017885,000054: 22,3051           77634                           RTB                                            
017886,000055: 22,3052           45547                                    V1STO2S                               
017887,000056: 22,3053           03267                           STORE    NCDU                                  #  NEW CDU ANGLES
017888,000057: 22,3054           77414                           BONCLR   EXIT                                  
017889,000058: 22,3055           01215                                    CALCMAN2                              
017890,000059: 22,3056           45142                                    MANUSTAT                              #  TO START MANEUVER
017891,000060: 22,3057           34711                           CAF      TWO                                   #           +0 OTHERWISE
017892,000061: 22,3060           55664        INCRDCDU           TS       KSPNDX                                
017893,000062: 22,3061           60000                           DOUBLE                                         
017894,000063: 22,3062           55665                           TS       KDPNDX                                
017895,000064: 22,3063           51664                           INDEX    KSPNDX                                
017896,000065: 22,3064           31666                           CA       NCDU                                  #  NEW DESIRED CDU ANGLES
017897,000066: 22,3065           00006                           EXTEND                                         
017898,000067: 22,3066           51664                           INDEX    KSPNDX                                
017899,000068: 22,3067           21661                           MSU      BCDU                                  #  INITIAL S/C ANGLE OR PREVIOUS DESIRED
017900,000069: 22,3070           00006                           EXTEND                                         #  CDU ANGLES
017901,000070: 22,3071           73141                           MP       DT/TAU                                
017902,000071: 22,3072           51665                           INDEX    KDPNDX                                
017903,000072: 22,3073           53576                           DXCH     DELCDUX                               #  ANGLE INCREMENTS TO BE ADDED TO

Page 406

017905,000074: 22,3074           51664                           INDEX    KSPNDX                                #  DCDU EVERY TENTH SEC
017906,000075: 22,3075           31666                           CA       NCDU                                  #  BY LEM DAP
017907,000076: 22,3076           51664                           INDEX    KSPNDX                                
017908,000077: 22,3077           57661                           XCH      BCDU                                  
017909,000078: 22,3100           51665                           INDEX    KDPNDX                                
017910,000079: 22,3101           55646                           TS       CDUXD                                 
017911,000080: 22,3102           11664                           CCS      KSPNDX                                
017912,000081: 22,3103           13060                           TCF      INCRDCDU                              #  LOOP FOR THREE AXES
017913,000082: 
017914,000083: 22,3104           00003                           RELINT                                         
017915,000084:                                                                                                  #  COMPARE PRESENT TIME WITH TIME TO TERMINATE MANEUVER
017916,000085: 
017917,000086: 22,3105           03115        TMANUCHK           TC       TIMECHK                               
017918,000087: 22,3106           13206                           TCF      CONTMANU                              
017919,000088: 22,3107           34712                           CAF      ONE                                   
017920,000089: 22,3110           05140        MANUSTAL           TC       WAITLIST                              

2016-08-14 RSB Added SBANK for addressing discrepancies.

017922,000091: 22,3111  40,2000                                  SBANK=   PINSUPER                              
017923,000092: 22,3111  E6,1661                                  EBANK=   BCDU                                  
017924,000093: 22,3111           03232 44106                     2CADR    MANUSTOP                              
017925,000094: 22,3113           00003                           RELINT                                         
017926,000095: 22,3114           15112                           TCF      ENDOFJOB                              
017927,000096: 
017928,000097: 
017929,000098: 22,3115           00006        TIMECHK            EXTEND                                         
017930,000099: 22,3116           40025                           DCS      TIME2                                 
017931,000100: 22,3117           53673                           DXCH     TTEMP                                 
017932,000101: 22,3120           00006                           EXTEND                                         
017933,000102: 22,3121           31717                           DCA      TM                                    
017934,000103: 22,3122           21673                           DAS      TTEMP                                 
017935,000104: 22,3123           11672                           CCS      TTEMP                                 
017936,000105: 22,3124           00002                           TC       Q                                     
017937,000106: 22,3125           13127                           TCF      +2                                    
017938,000107: 22,3126           13137                           TCF      2NDRETRN                              
017939,000108: 22,3127           11673                           CCS      TTEMP      +1                         
017940,000109: 22,3130           00002                           TC       Q                                     
017941,000110: 22,3131           13133                           TCF      MANUOFF                               
017942,000111: 22,3132           40000                           COM                                            
017943,000112: 22,3133           63205        MANUOFF            AD       ONESEC     +1                         
017944,000113: 22,3134           00006                           EXTEND                                         
017945,000114: 22,3135           63137                           BZMF     2NDRETRN                              
017946,000115: 22,3136           24002                           INCR     Q                                     
017947,000116: 22,3137           24002        2NDRETRN           INCR     Q                                     
017948,000117: 22,3140           00002                           TC       Q                                     
017949,000118: 22,3141           03146        DT/TAU             DEC      .1                                    
017950,000119: 
017951,000120: 22,3142           77776        MANUSTAT           EXIT                                           #  INITIALIZATION ROUTINE
017952,000121: 22,3143           00006                           EXTEND                                         #  FOR AUTOMATIC MANEUVERS
017953,000122: 22,3144           30025                           DCA      TIME2                                 
017954,000123: 22,3145           21717                           DAS      TM                                    #  TM+T0    MANEUVER COMPLETION TIME
017955,000124: 22,3146           00006                           EXTEND                                         

Page 407

017957,000126: 22,3147           43205                           DCS      ONESEC                                
017958,000127: 22,3150           21717                           DAS      TM                                    #  (TM+T0)-1
017959,000128: 22,3151           00004                           INHINT                                         
017960,000129: 22,3152           44712                           CS       ONE                                   #  ENABLE AUTOPILOT TO PERFORM
017961,000130: 22,3153           55332                           TS       HOLDFLAG                              #  AUTOMATIC MANEUVERS
017962,000131: 22,3154           41130                           CS       RATEINDX                              #  SEE IF MANEUVERING AT HIGH RATE
017963,000132: 22,3155           66211                           AD       SIX                                   
017964,000133: 22,3156           00006                           EXTEND                                         
017965,000134: 22,3157           63161                           BZMF     HIGHGAIN                              
017966,000135: 22,3160           13164                           TCF      +4                                    
017967,000136: 22,3161           41501        HIGHGAIN           CS       RCSFLAGS                              #  IF SO, SET HIGH RATE FLAG (BIT 15 OF
017968,000137: 22,3162           74674                           MASK     BIT15                                 #  RCSFLAGS)
017969,000138: 22,3163           27501                           ADS      RCSFLAGS                              
017970,000139: 22,3164           53711                           DXCH     BRATE                                 #  X-AXIS MANEUVER RATE
017971,000140: 22,3165           53526                           DXCH     WBODY                                 
017972,000141: 22,3166           53713                           DXCH     BRATE      +2                         #  Y-AXIS MANEUVER RATE
017973,000142: 22,3167           53530                           DXCH     WBODY1                                
017974,000143: 22,3170           53715                           DXCH     BRATE      +4                         #  Z-AXIS MANEUVER RATE
017975,000144: 22,3171           53532                           DXCH     WBODY2                                
017976,000145: 22,3172           31675                           CA       BIASTEMP   +1                         #  INSERT ATTITUDE ERROR BIASES
017977,000146: 22,3173           55564                           TS       BIAS                                  #  INTO AUTOPILOT
017978,000147: 22,3174           31677                           CA       BIASTEMP   +3                         
017979,000148: 22,3175           55565                           TS       BIAS1                                 
017980,000149: 22,3176           31701                           CA       BIASTEMP   +5                         
017981,000150: 22,3177           55566                           TS       BIAS2                                 
017982,000151: 22,3200           30025                           CA       TIME1                                 
017983,000152: 22,3201           63205                           AD       ONESEC     +1                         
017984,000153: 22,3202           57671                           XCH      NEXTIME                               
017985,000154: 22,3203           13057                           TCF      INCRDCDU   -1                         
017986,000155: 
017987,000156: 22,3204           00000        ONESEC             DEC      0          B-14                       
017988,000157: 22,3205           00144                           DEC      100        B-14                       
017989,000158: 
017990,000159: 22,3206           00004        CONTMANU           INHINT                                         #  CONTINUE WITH UPDATE PROCESS
017991,000160: 22,3207           40025                           CS       TIME1                                 
017992,000161: 22,3210           61671                           AD       NEXTIME                               
017993,000162: 22,3211           10000                           CCS      A                                     
017994,000163: 22,3212           64712                           AD       ONE                                   
017995,000164: 22,3213           13216                           TCF      MANUCALL                              
017996,000165: 22,3214           64674                           AD       NEGMAX                                
017997,000166: 22,3215           40000                           COM                                            
017998,000167: 22,3216           05140        MANUCALL           TC       WAITLIST                              

2016-08-14 RSB Added SBANK for addressing discrepancies.

018000,000169: 22,3217  40,2000                                  SBANK=   PINSUPER                              
018001,000170: 22,3217  E6,1661                                  EBANK=   BCDU                                  
018002,000171: 22,3217           03225 44106                     2CADR    UPDTCALL                              
018003,000172: 22,3221           00003                           RELINT                                         
018004,000173: 22,3222           33205                           CAF      ONESEC     +1                         #  INCREMENT TIME FOR NEXT UPDATE
018005,000174: 22,3223           27671                           ADS      NEXTIME                               
018006,000175: 22,3224           15112                           TCF      ENDOFJOB                              
018007,000176: 

Page 408

018009,000178: 22,3225           37663        UPDTCALL           CAF      PRIO26                                #  CALL FOR UPDATE
018010,000179: 22,3226           05042                           TC       FINDVAC                               #  OF STEERING COMMANDS

2016-08-14 RSB Added SBANK for addressing discrepancies.

018012,000181: 22,3227  40,2000                                  SBANK=   PINSUPER                              
018013,000182: 22,3227  E6,1661                                  EBANK=   BCDU                                  
018014,000183: 22,3227           03027 44106                     2CADR    NEWDELHI                              
018015,000184: 22,3231           05213                           TC       TASKOVER                              
018016,000185: 

Page 409

018018,000187:                                                                                                  #  ROUTINE FOR TERMINATING AUTOMATIC MANEUVERS
018019,000188: 
018020,000189: 22,3232           03256        MANUSTOP           TC       STOPYZ                                
018021,000190: 22,3233           03303                           TC       LOADYZ                                
018022,000191: 
018023,000192: 22,3234           31155        ENDROLL            CA       CPHI                                  
018024,000193: 22,3235           55646                           TS       CDUXD                                 #  SET CDUXD TO THE COMMANDED OUTER GIMBAL
018025,000194: 22,3236           03245                           TC       STOPRATE                              
018026,000195: 22,3237           31327        ENDMANU            CA       ATTPRIO                               #  RESTORE USERS PRIORITY
018027,000196: 22,3240           54063                           TS       NEWPRIO                               
018028,000197: 
018029,000198: 22,3241           34714                           CA       ZERO                                  #  ZERO ATTCADR
018030,000199: 22,3242           53326                           DXCH     ATTCADR                               
018031,000200: 
018032,000201: 22,3243           05053                           TC       SPVAC                                 #  RETURN TO USER OF GOMANUR
018033,000202: 
018034,000203: 22,3244           05213                           TC       TASKOVER                              
018035,000204: 
018036,000205: 22,3245           34714        STOPRATE           CAF      ZERO                                  
018037,000206: 22,3246           55575                           TS       DELCDUX                               
018038,000207: 22,3247           55576                           TS       DELCDUX    +1                         #  ZERO ROLL INCREMENTAL ANGLES
018039,000208: 22,3250           55525                           TS       WBODY                                 #  RATE
018040,000209: 22,3251           55526                           TS       WBODY      +1                         
018041,000210: 22,3252           55564                           TS       BIAS                                  #  BIAS
018042,000211: 
018043,000212: 22,3253           44674                           CS       BIT15                                 #  MAKE SURE HIGH RATE FLAG (BIT 15 OF
018044,000213: 22,3254           71501                           MASK     RCSFLAGS                              #  RCSFLAGS) IS RESET.
018045,000214: 22,3255           55501                           TS       RCSFLAGS                              
018046,000215: 
018047,000216: 22,3256           34714        STOPYZ             CAF      ZERO                                  
018048,000217: 22,3257           55577                           TS       DELCDUY                               #  ZERO PITCH, YAW
018049,000218: 22,3260           55600                           TS       DELCDUY    +1                         #  INCREMENTAL ANGLES
018050,000219: 22,3261           55601                           TS       DELCDUZ                               
018051,000220: 22,3262           55602                           TS       DELCDUZ    +1                         
018052,000221: 22,3263           55527                           TS       WBODY1                                #  RATES
018053,000222: 22,3264           55530                           TS       WBODY1     +1                         
018054,000223: 22,3265           55531                           TS       WBODY2                                
018055,000224: 22,3266           55532                           TS       WBODY2     +1                         
018056,000225: 22,3267           55565                           TS       BIAS1                                 #  BIASES
018057,000226: 22,3270           55566                           TS       BIAS2                                 
018058,000227: 22,3271           00002                           TC       Q                                     
018059,000228: 
018060,000229: 22,3272           30032        ZEROEROR           CA       CDUX                                  #  PICK UP CDU ANGLES AND STORE IN
018061,000230: 22,3273           55646                           TS       CDUXD                                 #  CDU DESIRED
018062,000231: 22,3274           30033                           CA       CDUY                                  
018063,000232: 22,3275           55650                           TS       CDUYD                                 
018064,000233: 22,3276           30034                           CA       CDUZ                                  
018065,000234: 22,3277           55652                           TS       CDUZD                                 
018066,000235: 22,3300           00002                           TC       Q                                     
018067,000236: 

Page 410

018069,000238: 22,3301           31155        LOADCDUD           CA       CPHI                                  #  STORE TERMINAL ANGLES INTO
018070,000239: 22,3302           55646                           TS       CDUXD                                 #  COMMAND ANGLES
018071,000240: 22,3303           31156        LOADYZ             CA       CTHETA                                
018072,000241: 22,3304           55650                           TS       CDUYD                                 
018073,000242: 22,3305           31157                           CA       CPSI                                  
018074,000243: 22,3306           55652                           TS       CDUZD                                 
018075,000244: 22,3307           00002                           TC       Q                                     

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