Source Code

These source-code files are part of a reconstructed copy of Comanche 45/2 (AKA Manche45 revision 2), the final, flown mission release of the Apollo 10 Command Module (CM) Apollo Guidance Computer (AGC) software. Comanche 45/2 was preceded by Comanche 44 and Comanche 45. The reconstruction is believed to be exactly accurate, but in the absence of an actual Apollo-era listing of Comanche 45/2, some explanation of the reconstruction process is needed to insure confidence in that accuracy.

The starting point was the source code of Comanche 45 (itself previously accurately reconstructed). Comanche 45 source code was then modified by incorporating changes known from contemporary documentation to have been made between revisions 45 and 45/2. The now-reconstructed Comanche 45/2 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 tend to match those in the Comanche 55, the most-similar revision of Comanche for which we have access to an actual non-reconstructed hardcopy; the source code would likely have different page numbers in a contemporary Comanche 45 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 44. Here's a guide to the Apollo documentation referenced in those annotations:
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.

063007,000002:                                                                                                  ## Copyright:   Public domain.
063008,000003:                                                                                                  ## Filename:    SERVICE_ROUTINES.agc
063009,000004:                                                                                                  ## Purpose:     A section of Manche45 revision 2.
063010,000005:                                                                                                  ##              It is part of the reconstructed source code for the
063011,000006:                                                                                                  ##              final, flown release of the flight software for the Command
063012,000007:                                                                                                  ##              Module's (CM) Apollo Guidance Computer (AGC) for Apollo 10.
063013,000008:                                                                                                  ##              The code has been recreated from a copy of Comanche 055. It
063014,000009:                                                                                                  ##              has been adapted such that the resulting bugger words
063015,000010:                                                                                                  ##              exactly match those specified for Manche 45/2 in NASA drawing
063016,000011:                                                                                                  ##              2021153D, which gives relatively high confidence that the
063017,000012:                                                                                                  ##              reconstruction is correct.
063018,000013:                                                                                                  ## Assembler:   yaYUL
063019,000014:                                                                                                  ## Contact:     Ron Burkey <info@sandroid.org>.
063020,000015:                                                                                                  ## Website:     www.ibiblio.org/apollo/index.html
063021,000016:                                                                                                  ## Mod history: 2020-12-24 MAS  Created from Comanche 45.
063022,000017: 

Page 1485

063024,000019:    7722                                           BLOCK    3                                     
063025,000020:    6000                                           SETLOC   FFTAG6                                
063026,000021:    6000                                           BANK                                           
063027,000022:    7722                                           COUNT    03/FLAG                               
063028,000023: 
063029,000024:    7722           54001        UPENT2             TS       L                                     #  WHICH FLAGWORD IS IT
063030,000025:    7723           75023                           MASK     OCT7                                  
063031,000026:    7724           56001                           XCH      L                                     #  SAVE IN L FOR INDEXING
063032,000027: 
063033,000028:    7725           75731                           MASK     OCT77770                              #  OBTAIN THE BIT INFORMATION
063034,000029:    7726           00004                           INHINT                                         #  PREVENT INTERUPTS
063035,000030:    7727           54061                           TS       ITEMP1                                #  STORE THE BIT INFORMATION TEMPORARIALY
063036,000031: 
063037,000032:    7730           50001                           NDX      L                                     
063038,000033:    7731           40074                           CS       FLAGWRD0                              
063039,000034:    7732           70061                           MASK     ITEMP1                                
063040,000035:    7733           50001                           NDX      L                                     
063041,000036:    7734           26074                           ADS      FLAGWRD0                              
063042,000037:    7735           00003                           RELINT                                         #  RELEASE INTERUPT INHIBIT
063043,000038: 
063044,000039:    7736           24002                           INCR     Q                                     #  OBTAIN THE CORRECT RETURN ADDRESS
063045,000040:    7737           00002                           TC       Q                                     #  RETURN
063046,000041: 
063047,000042:    7740           54001        DOWNENT2           TS       L                                     #  WHICH FLAGWORD IS IT
063048,000043:    7741           75023                           MASK     OCT7                                  
063049,000044:    7742           56001                           XCH      L                                     #  SAVE IN L FOR INDEXING
063050,000045: 
063051,000046:    7743           75731                           MASK     OCT77770                              #  OBTAIN THE BIT INFORMATION
063052,000047:    7744           40000                           COM                                            #  START TO PROCESS THE INFORMATION
063053,000048: 
063054,000049:    7745           00004                           INHINT                                         #  PREVENT INTERUPTS
063055,000050:    7746           50001                           NDX      L                                     
063056,000051:    7747           70074                           MASK     FLAGWRD0                              
063057,000052:    7750           50001                           NDX      L                                     
063058,000053:    7751           54074                           TS       FLAGWRD0                              
063059,000054:    7752           00003                           RELINT                                         #  RELEASE INTERUPT INHIBIT
063060,000055: 
063061,000056:    7753           24002                           INCR     Q                                     #  OBTAIN THE CORRECT RETURN ADDRESS
063062,000057:    7754           00002                           TC       Q                                     #  RETURN
063063,000058: 
063064,000059:    7755     5023               OCT7               EQUALS   SEVEN                                 
063065,000060: 10,3766                                           BANK     10                                    
063066,000061: 

Page 1486

063068,000063:                                                                                                  #  UPFLAG AND DOWNFLAG ARE ENTIRELY GENERAL FLAG SETTING AND CLEARING SUBROUTINES.  USING THEM, WHETHER OR
063069,000064:                                                                                                  #  NOT IN INTERRUPT, ONE MAY SET OR CLEAR ANY SINGLE, NAMED BIT IN ANY ERASABLE REGISTER, SUBJECT OF COURSE TO
063070,000065:                                                                                                  #  EBANK SETTING.  A "NAMED" BIT, AS THE WORD IS USED HERE, IS ANY BIT WITH A NAME FORMALLY ASSIGNED BY THE YUL
063071,000066:                                                                                                  #  ASSEMBLER.
063072,000067: 
063073,000068:                                                                                                  #  AT PRESENT THE ONLY NAMED BITS ARE THOSE IN THE FLAGWORDS.  ASSEMBLER CHANGES WILL MAKE IT POSSIBLE TO
063074,000069:                                                                                                  #  NAME ANY BIT IN ERASABLE MEMORY.
063075,000070: 
063076,000071:                                                                                                  #  CALLING SEQUENCES ARE AS FOLLOWS:-
063077,000072:                                                                                                  #                TC      UPFLAG                  TC      DOWNFLAG
063078,000073:                                                                                                  #                ADRES   NAME OF FLAG            ADRES   NAME OF FLAG
063079,000074: 
063080,000075:                                                                                                  #  RETURN IS TO THE LOCATION FOLLOWING THE "ADRES" ABOUT .58 MS AFTER THE "TC".
063081,000076:                                                                                                  #  UPON RETURN A CONTAINS THE CURRENT FLAGWRD SETTING.
063082,000077: 
063083,000078:    5546                                           BLOCK    02                                    
063084,000079:    4000                                           SETLOC   FFTAG1                                
063085,000080:    4000                                           BANK                                           
063086,000081:    5546                                           COUNT*   $$/FLAG                               
063087,000082: 
063088,000083:    5546           30002        UPFLAG             CA       Q                                     
063089,000084:    5547           05564                           TC       DEBIT                                 
063090,000085:    5550           40000                           COM                                            #  +(15 - BIT)
063091,000086:    5551           00006                           EXTEND                                         
063092,000087:    5552           04001                           ROR      LCHAN                                 #  SET BIT
063093,000088:    5553           50061        COMFLAG            INDEX    ITEMP1                                
063094,000089:    5554           54074                           TS       FLAGWRD0                              
063095,000090:    5555           22063                           LXCH     ITEMP3                                
063096,000091:    5556           00003                           RELINT                                         
063097,000092:    5557           00001                           TC       L                                     
063098,000093: 
063099,000094:    5560           30002        DOWNFLAG           CA       Q                                     
063100,000095:    5561           05564                           TC       DEBIT                                 
063101,000096:    5562           70001                           MASK     L                                     #  RESET BIT
063102,000097:    5563           15553                           TCF      COMFLAG                               
063103,000098: 
063104,000099:    5564           65017        DEBIT              AD       ONE                                   #  GET DE BITS
063105,000100:    5565           00004                           INHINT                                         
063106,000101:    5566           54063                           TS       ITEMP3                                
063107,000102:    5567           35026                           CA       LOW4                                  #  DEC15
063108,000103:    5570           54061                           TS       ITEMP1                                
063109,000104:    5571           50063                           INDEX    ITEMP3                                
063110,000105:    5572           27777                           CA       0          -1                         #  ADRES
063111,000106:    5573           54001                           TS       L                                     
063112,000107:    5574           35021                           CA       ZERO                                  

Page 1487

063114,000109:    5575           00006                           EXTEND                                         
063115,000110:    5576           10061                           DV       ITEMP1                                #  A = FLAGWRD, L = (15 - BIT)
063116,000111:    5577           52062                           DXCH     ITEMP1                                
063117,000112:    5600           50061                           INDEX    ITEMP1                                
063118,000113:    5601           30074                           CA       FLAGWRD0                              
063119,000114:    5602           54001                           TS       L                                     #  CURRENT STATE
063120,000115:    5603           50062                           INDEX    ITEMP2                                
063121,000116:    5604           45001                           CS       BIT15                                 #  -(15 - BIT)
063122,000117:    5605           00002                           TC       Q                                     
063123,000118: 

Page 1488

063125,000120:                                                                                                  #  DELAYJOB- A GENERAL ROUTINE TO DELAY A JOB A SPECIFIC AMOUNT OF TIME BEFORE PICKING UP AGAIN.
063126,000121: 
063127,000122:                                                                                                  #  ENTRANCE REQUIREMENTS...
063128,000123:                                                                                                  #                CAF     DT              DELAY JOB FOR DT CENTISECS
063129,000124:                                                                                                  #                TC      BANKCALL
063130,000125:                                                                                                  #                CADR    DELAYJOB
063131,000126: 
063132,000127: 06,3770                                           BANK     06                                    
063133,000128: 00,2000                                           SETLOC   DLAYJOB                               
063134,000129: 00,2000                                           BANK                                           
063135,000130: 
063136,000131:                                                                                                  #  THIS MUST REMAIN IN BANK 0 *****************************************
063137,000132: 
063138,000133: 00,3732                                           COUNT    00/DELAY                              
063139,000134: 
063140,000135: 00,3732           00004        DELAYJOB           INHINT                                         
063141,000136: 00,3733           54002                           TS       Q                                     #  STORE DELAY DT IN Q FOR DLY -1 IN
063142,000137: 00,3734           36214                           CAF      DELAYNUM                              #  WAITLIST
063143,000138: 00,3735           54070        DELLOOP            TS       RUPTREG1                              
063144,000139: 00,3736           50000                           INDEX    A                                     
063145,000140: 00,3737           31141                           CA       DELAYLOC                              #  IS THIS DELAYLOC AVAILABLE
063146,000141: 00,3740           00006                           EXTEND                                         
063147,000142: 00,3741           13746                           BZF      OK2DELAY                              #  YES
063148,000143: 
063149,000144: 00,3742           10070                           CCS      RUPTREG1                              #  NO, TRY NEXT DELAYLOC
063150,000145: 00,3743           13735                           TCF      DELLOOP                               
063151,000146: 
063152,000147: 00,3744           07755                           TC       BAILOUT                               #  NO AVAILABLE LOCS AVAILABLE.
063153,000148: 00,3745           01104                           OCT      1104                                  
063154,000149: 
063155,000150: 00,3746           33766        OK2DELAY           CA       TCSLEEP                               #  SET WAITLIST IMMEDIATE RETURN
063156,000151: 00,3747           54061                           TS       WAITEXIT                              
063157,000152: 
063158,000153: 00,3750           30004                           CA       FBANK                                 
063159,000154: 00,3751           60070                           AD       RUPTREG1                              #  STORE BBANK FOR TASK CALL
063160,000155: 00,3752           54001                           TS       L                                     
063161,000156: 
063162,000157: 00,3753           33767                           CAF      WAKECAD                               #  STORE CADR FOR TASK CALL
063163,000158: 00,3754           15255                           TCF      DLY2       -1                         #  DLY IS IN WAITLIST ROUTINE
063164,000159: 
063165,000160: 00,3755           04711        TCGETCAD           TC       MAKECADR                              #  GET CALLERS FCADR
063166,000161: 
063167,000162: 00,3756           50070                           INDEX    RUPTREG1                              
063168,000163: 00,3757           55141                           TS       DELAYLOC                              #  SAVE DELAY CADRS
063169,000164: 
063170,000165: 00,3760           05175                           TC       JOBSLEEP                              
063171,000166: 
063172,000167: 00,3761           35021        WAKER              CAF      ZERO                                  
063173,000168: 00,3762           50006                           INDEX    BBANK                                 
063174,000169: 00,3763           57141                           XCH      DELAYLOC                              #  MAKE DELAYLOC AVAILABLE

Page 1489

063176,000171: 00,3764           05201                           TC       JOBWAKE                               
063177,000172: 
063178,000173: 00,3765           05324                           TC       TASKOVER                              
063179,000174: 
063180,000175: 00,3766           03753        TCSLEEP            GENADR   TCGETCAD   -2                         
063181,000176: 00,3767           03761        WAKECAD            GENADR   WAKER                                 
063182,000177: 

Page 1490

063184,000179:                                                                                                  #  GENTRAN, A BLOCK TRANSFER ROUTINE.
063185,000180:                                                                                                  #  WRITTEN BY D. EYLES
063186,000181:                                                                                                  #  MOD 1 BY KERNAN                               UTILITYM REV 17 11/18/67
063187,000182:                                                                                                  #  MOD 2 BY SCHULENBERG  (REMOVE RELINT)  SKIPPER REV 4 2/28/68
063188,000183: 
063189,000184:                                                                                                  #  THIS ROUTINE IS USEFULL FOR TRANSFERING N CONSECUTIVE ERASABLE OR FIXED QUANTITIES TO SOME OTHER N
063190,000185:                                                                                                  #  CONSECUTIVE ERASABLE LOCATIONS.  IF BOTH BLOCKS OF DATA ARE IN SWITCHABLE EBANKS, THEY MUST BE IN THE SAME ONE.
063191,000186: 
063192,000187:                                                                                                  #  GENTRAN IS CALLABLE IN A JOB AS WELL AS A RUPT.  THE CALLING SEQUENCE IS:
063193,000188:                                                                                                  #        I       CA      N-1             # OF QUANTITIES MINUS ONE.
063194,000189:                                                                                                  #        I +1    TC      GENTRAN         IN FIXED-FIXED.
063195,000190:                                                                                                  #        I +2    ADRES   L               STARTING ADRES OF DATA TO BE MOVED.
063196,000191:                                                                                                  #        I +3    ADRES   M               STARTING ADRES OF DUPLICATION BLOCK.
063197,000192:                                                                                                  #        I +4                            RETURNS HERE.
063198,000193: 
063199,000194:                                                                                                  #  GENTRAN TAKES 25 MCT'S (300 MICROSECONDS) PER ITEM + 5 MCT'S (60 MICS) FOR ENTERING AND EXITING.
063200,000195:                                                                                                  #  A, L AND ITEMP1 ARE NOT PRESERVED.
063201,000196: 
063202,000197:    5606                                           BLOCK    02                                    
063203,000198:    4000                                           SETLOC   FFTAG4                                
063204,000199:    4000                                           BANK                                           
063205,000200: 
063206,000201:    5606     0061                                  EBANK=   ITEMP1                                
063207,000202: 
063208,000203:    5606                                           COUNT*   $$/TRAN                               
063209,000204: 
063210,000205:    5606           00004        GENTRAN            INHINT                                         
063211,000206:    5607           54061                           TS       ITEMP1                                #  SAVE N-1.
063212,000207:    5610           50002                           INDEX    Q                                     #  C(Q) = ADRES L.
063213,000208:    5611           60000                           AD       0                                     #  ADRES (L + N - 1).
063214,000209:    5612           50000                           INDEX    A                                     
063215,000210:    5613           30000                           CA       0                                     #  C(ABOVE).
063216,000211:    5614           54001                           TS       L                                     #  SAVE DATA.
063217,000212:    5615           30061                           CA       ITEMP1                                
063218,000213:    5616           50002                           INDEX    Q                                     
063219,000214:    5617           60001                           AD       1                                     #  ADRES (M + N - 1).
063220,000215:    5620           50000                           INDEX    A                                     
063221,000216:    5621           22000                           LXCH     0                                     #  STUFF IT.
063222,000217:    5622           10061                           CCS      ITEMP1                                #  LOOP UNTIL N-1 = 0.
063223,000218:    5623           15607                           TCF      GENTRAN    +1                         
063224,000219:    5624           16710                           TCF      Q+2                                   #  RETURN TO CALLER.
063225,000220: 

Page 1491

063227,000222:                                                                                                  #  B5OFF         ZERO BIT 5 OF EXTVBACT, WHICH IS SET BY TESTXACT.
063228,000223:                                                                                                  #  MAY BE USED AS NEEDED BY ANY EXTENDED VERB WHICH HAS DONE TESTXACT
063229,000224: 
063230,000225:    5625                                           COUNT*   $$/EXTVB                              
063231,000226: 
063232,000227:    5625           45013        B5OFF              CS       BIT5                                  
063233,000228:    5626           71044                           MASK     EXTVBACT                              
063234,000229:    5627           55044                           TS       EXTVBACT                              
063235,000230:    5630           05217                           TC       ENDOFJOB                              
063236,000231: 

Page 1492

063238,000233:                                                                                                  #  SUBROUTINES TO TURN OFF AND TURN ON TRACKER FAIL LIGHT.
063239,000234: 
063240,000235:    5631           00004        TRFAILOF           INHINT                                         
063241,000236:    5632           47704                           CS       OCT40200                              #  TURN OFF TRACKER LIGHT
063242,000237:    5633           71036                           MASK     DSPTAB     +11D                       
063243,000238:    5634           65001                           AD       BIT15                                 
063244,000239:    5635           55036                           TS       DSPTAB     +11D                       
063245,000240:    5636           41331                           CS       OPTMODES                              #  TO INSURE THAT OCDU FAIL WILL GO ON
063246,000241:    5637           75011                           MASK     BIT7                                  #  AGAIN IF IT WAS ON IN ADDITION TO
063247,000242:    5640           27331                           ADS      OPTMODES                              #  TRACKER FAIL.
063248,000243: 
063249,000244:    5641           00003        REQ                RELINT                                         
063250,000245:    5642           00002                           TC       Q                                     
063251,000246: 
063252,000247:    5643           00004        TRFAILON           INHINT                                         
063253,000248:    5644           41036                           CS       DSPTAB     +11D                       #  TURN ON
063254,000249:    5645           77704                           MASK     OCT40200                              
063255,000250:    5646           27036                           ADS      DSPTAB     +11D                       
063256,000251:    5647           15641                           TCF      REQ                                   
063257,000252: 
063258,000253: 
063259,000254: 
063260,000255: 

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