Source Code
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This is the source-code for the Apollo 9 Command Module's Guidance Computer.
These 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A scan by Ron Burkey has superceded it, made from a more-legible copy from the collection of original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. 28,1968Note that the date is the date of the printout, not the date of the program revision. |
060517,000002: ## Copyright: Public domain.
060518,000003: ## Filename: RESTARTS_ROUTINE.agc
060519,000004: ## Purpose: Part of the source code for Colossus, build 249.
060520,000005: ## It is part of the source code for the Command Module's (CM)
060521,000006: ## Apollo Guidance Computer (AGC), for Apollo 9.
060522,000007: ## Assembler: yaYUL
060523,000008: ## Reference: Starts on p. 1382
060524,000009: ## Contact: Ron Burkey <info@sandroid.org>.
060525,000010: ## Website: www.ibiblio.org/apollo.
060526,000011: ## Mod history: 08/30/04 RSB. Adapted from corresponding Luminary131 file.
060527,000012: ## 2010-10-24 JL Added missing # in comment.
060528,000013: ## 2017-01-06 RSB Page numbers now agree with those on the
060529,000014: ## original harcopy, as opposed to the PDF page
060530,000015: ## numbers in 1701.pdf.
060531,000016: ## 2017-01-18 RSB Cross-diff'd comment text (not whitespace)
060532,000017: ## vs the already-proofed corresponding Colossus
060533,000018: ## 237 and Comanche 55 source-code files
060534,000019: ## and corrected errors found.
060535,000020: ## 2017-03-14 RSB Comment-text fixes noted in proofing Luminary 116.
060536,000021:
060537,000022: ## The contents of the "Colossus249" files, in general, are transcribed
060538,000023: ## from a scanned copy of the program listing. Notations on this
060539,000024: ## document read, in part:
060540,000025: ##
060541,000026: ## Assemble revision 249 of AGC program Colossus by NASA
060542,000027: ## 2021111-041. October 28, 1968.
060543,000028: ##
060544,000029: ## This AGC program shall also be referred to as
060545,000030: ## Colossus 1A
060546,000031: ##
060547,000032: ## Prepared by
060548,000033: ## Massachusetts Institute of Technology
060549,000034: ## 75 Cambridge Parkway
060550,000035: ## Cambridge, Massachusetts
060551,000036: ## under NASA contract NAS 9-4065.
060552,000037: ##
060553,000038: ## Refer directly to the online document mentioned above for further information.
060554,000039: ## Please report any errors (relative to the scanned pages) to info@sandroid.org.
060555,000040: ##
060556,000041: ## In some cases, where the source code for Luminary 131 overlaps that of
060557,000042: ## Colossus 249, this code is instead copied from the corresponding Luminary 131
060558,000043: ## source file, and then is proofed to incorporate any changes.
060559,000044: ## source file, and then is proofed to incorporate any changes.
060560,000045:
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Page 1382 |
060562,000047: 01,3520 BANK 01
060563,000048: 01,2000 SETLOC RESTART
060564,000049: 01,2000 BANK
060565,000050:
060566,000051: 01,3520 E3,1436 EBANK= PHSNAME1 # GOPROG MUST SWITCH TO THIS EBANK
060567,000052:
060568,000053: 01,3520 COUNT 01/RSROU
060569,000054:
060570,000055: 01,3520 30161 RESTARTS CA MPAC +5 # GET GROUP NUMBER -1
060571,000056: 01,3521 60000 DOUBLE # SAVE FOR INDEXING
060572,000057: 01,3522 54155 TS TEMP2G
060573,000058:
060574,000059: 01,3523 33762 CA PHS2CADR # SET UP EXIT IN CASE IT IS AN EVEN
060575,000060: 01,3524 54157 TS TEMPSWCH # TABLE PHASE
060576,000061:
060577,000062: 01,3525 33557 CA RTRNCADR # TO SAVE TIME ASSUME IT WILL GET NEXT
060578,000063: 01,3526 54707 TS GOLOC +2 # GROUP AFTER THIS
060579,000064:
060580,000065: 01,3527 30154 CA TEMPPHS
060581,000066: 01,3530 74744 MASK OCT1400
060582,000067: 01,3531 10000 CCS A # IS IT A VARIABLE OR TABLE RESTART
060583,000068: 01,3532 13543 TCF ITSAVAR # IT:S A VARIABLE RESTART
060584,000069:
060585,000070: 01,3533 10154 GETPART2 CCS TEMPPHS # IS IT AN X.1 RESTART
060586,000071: 01,3534 10000 CCS A
060587,000072: 01,3535 13643 TCF ITSATBL # NO, ITS A TABLE RESTART
060588,000073:
060589,000074: 01,3536 34761 CA PRIO14 # IT IS AN X.1 RESTART, THEREFORE START
060590,000075: 01,3537 05042 TC FINDVAC # THE DISPLAY RESTART JOB
060591,000076: 01,3540 E3,1400 EBANK= LST1
060592,000077: 01,3540 03165 20103 2CADR INITDSP
060593,000078:
060594,000079: 01,3542 03557 TC RTRNCADR # FINISHED WITH THIS GROUP, GET NEXT ONE
060595,000080:
060596,000081: 01,3543 74744 ITSAVAR MASK OCT1400 # IS IT TYPE B ?
060597,000082: 01,3544 10000 CCS A
060598,000083: 01,3545 13614 TCF ITSLIKEB # YES, IT IS TYPE B
060599,000084:
060600,000085: 01,3546 00006 EXTEND # STORE THE JOB (OR TASK) 2CADR FOR EXIT
060601,000086: 01,3547 50155 NDX TEMP2G
060602,000087: 01,3550 31437 DCA PHSNAME1
060603,000088: 01,3551 52706 DXCH GOLOC
060604,000089:
060605,000090: 01,3552 30154 CA TEMPPHS # SEE IF THIS IS A JOB, TASK, OR A LONGCAL
060606,000091: 01,3553 74716 MASK OCT7
060607,000092: 01,3554 67715 AD MINUS2
060608,000093: 01,3555 10000 CCS A
060609,000094: 01,3556 13726 TCF ITSLNGCL # ITS A LONGCALL
060610,000095:
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Page 1383 |
060612,000097: 01,3557 04570 RTRNCADR TC SWRETURN # CANT GET HERE
060613,000098: 01,3560 13562 TCF ITSAWAIT
060614,000099:
060615,000100: 01,3561 13627 TCF ITSAJOB # ITS A JOB
060616,000101:
060617,000102: 01,3562 33766 ITSAWAIT CA WTLTCADR # SET UP WAITLIST CALL
060618,000103: 01,3563 54704 TS GOLOC -1
060619,000104:
060620,000105: 01,3564 50155 NDX TEMP2G # DIRECTLY STORED
060621,000106: 01,3565 31054 CA PHSPRDT1
060622,000107: 01,3566 10000 TIMETEST CCS A # IS IT AN IMMEDIATE RESTART
060623,000108: 01,3567 24000 INCR A # NO,
060624,000109: 01,3570 13573 TCF FINDTIME # FIND OUT WHEN IT SHOULD BEGIN
060625,000110:
060626,000111: 01,3571 15367 TCF ITSINDIR # STORED INDIRECTLY
060627,000112:
060628,000113: 01,3572 13612 TCF IMEDIATE # IT WANTS AN IMMEDIATE RESTART
060629,000114:
060630,000115: # ***** THIS MUST BE IN FIXED FIXED *****
060631,000116:
060632,000117: 5367 BLOCK 02
060633,000118: 4000 SETLOC FFTAG2
060634,000119: 4000 BANK
060635,000120:
060636,000121: 5367 COUNT 02/RSROU
060637,000122:
060638,000123: 5367 22706 ITSINDIR LXCH GOLOC +1 # GET THE CORRECT E BANK IN CASE THIS IS
060639,000124: 5370 22006 LXCH BB # SWITCHED ERRASIBLE
060640,000125:
060641,000126: 5371 50000 NDX A # GET THE TIME INDIRECTLY
060642,000127: 5372 30001 CA 1
060643,000128:
060644,000129: 5373 22006 LXCH BB # RESTORE THE BB AND GOLOC
060645,000130: 5374 22706 LXCH GOLOC +1
060646,000131:
060647,000132: 5375 13573 TCF FINDTIME # FIND OUT WHEN IT SHOULD BEGIN
060648,000133:
060649,000134: # ***** YOU MAY RETURN TO SWITCHED FIXED *****
060650,000135:
060651,000136: 01,3573 BANK 01
060652,000137: 01,2000 SETLOC RESTART
060653,000138: 01,2000 BANK
060654,000139:
060655,000140: 01,3573 COUNT 01/RSROU
060656,000141:
060657,000142: 01,3573 40000 FINDTIME COM # MAKE NEGITIVE SINCE IT WILL BE SUBTRACTD
060658,000143: 01,3574 54001 TS L # AND SAVE
060659,000144: 01,3575 50155 NDX TEMP2G
060660,000145: 01,3576 41053 CS TBASE1
060661,000146: 01,3577 00006 EXTEND
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Page 1384 |
060663,000148: 01,3600 60025 SU TIME1
060664,000149: 01,3601 10000 CCS A
060665,000150: 01,3602 40000 COM
060666,000151: 01,3603 67700 AD OCT37776
060667,000152: 01,3604 64712 AD ONE
060668,000153: 01,3605 60001 AD L
060669,000154: 01,3606 10000 CCS A
060670,000155: 01,3607 34714 CA ZERO
060671,000156: 01,3610 13612 TCF +2
060672,000157: 01,3611 13612 TCF +1
060673,000158: 01,3612 64712 IMEDIATE AD ONE
060674,000159: 01,3613 00704 TC GOLOC -1
060675,000160: 01,3614 33557 ITSLIKEB CA RTRNCADR # TYPE B, SO STORE RETURN IN
060676,000161: 01,3615 54157 TS TEMPSWCH # TEMPSWCH IN CASE OF AN EVEN PHASE
060677,000162:
060678,000163: 01,3616 33763 CA PRT2CADR # SET UP EXIT TO GET TABLE PART OF THIS
060679,000164: 01,3617 54707 TS GOLOC +2 # VARIABLE TYPE OF PHASE
060680,000165:
060681,000166: 01,3620 30154 CA TEMPPHS # MAKE THE PHASE LOOK RIGHT FOR THE TABLE
060682,000167: 01,3621 76043 MASK OCT177 # PART OF THIS VARIABLE PHASE
060683,000168: 01,3622 54154 TS TEMPPHS
060684,000169:
060685,000170: 01,3623 00006 EXTEND
060686,000171: 01,3624 50155 NDX TEMP2G # OBTAIN THE JOB:S 2CADR
060687,000172: 01,3625 31437 DCA PHSNAME1
060688,000173: 01,3626 52706 DXCH GOLOC
060689,000174:
060690,000175: 01,3627 50155 ITSAJOB NDX TEMP2G # NOW ADD THE PRIORITY AND LET:S GO
060691,000176: 01,3630 31054 CA PHSPRDT1
060692,000177: 01,3631 54704 CHKNOVAC TS GOLOC -1 # SAVE PRIO UNTIL WE SEE IF ITS
060693,000178: 01,3632 00006 EXTEND # A FINDVAC OR A NOVAC
060694,000179: 01,3633 63637 BZMF ITSNOVAC
060695,000180:
060696,000181: 01,3634 33765 CAF FVACCADR # POSITIVE, SET UP FINDVAC CALL.
060697,000182: 01,3635 56704 XCH GOLOC -1 # PICK UP PRIO,
060698,000183: 01,3636 00704 TC GOLOC -1 # AND GO
060699,000184:
060700,000185: 01,3637 33767 ITSNOVAC CAF NOVACADR # NEGATIVE,
060701,000186: 01,3640 56704 XCH GOLOC -1 # SET UP NOVAC CALL,
060702,000187: 01,3641 40000 COM # CORRECT PRIO,
060703,000188: 01,3642 00704 TC GOLOC -1 # AND GO
060704,000189:
060705,000190: 01,3643 54020 ITSATBL TS CYR # FIND OUT IF THE PHASE IS ODD OR EVEN
060706,000191: 01,3644 10020 CCS CYR
060707,000192: 01,3645 13646 TCF +1 # IT:S EVEN
060708,000193: 01,3646 13744 TCF ITSEVEN
060709,000194:
060710,000195: 01,3647 33557 CA RTRNCADR # IN CASE THIS IS THE SECOND PART OF A
060711,000196: 01,3650 54707 TS GOLOC +2 # TYPE B RESTART, WE NEED PROPER EXIT
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Page 1385 |
060713,000198: 01,3651 30154 CA TEMPPHS # SET UP POINTER FOR FINDING OUR PLACE IN
060714,000199: 01,3652 54021 TS SR # THE RESTART TABLES
060715,000200: 01,3653 60021 AD SR
060716,000201: 01,3654 50155 NDX TEMP2G
060717,000202: 01,3655 62001 AD SIZETAB +1
060718,000203: 01,3656 54156 TS POINTER
060719,000204:
060720,000205: 01,3657 00006 CONTBL2 EXTEND # FIND OUT WHAT:S IN THE TABLE
060721,000206: 01,3660 50156 NDX POINTER
060722,000207: 01,3661 32002 DCA CADRTAB # GET THE 2CADR
060723,000208:
060724,000209: 01,3662 22706 LXCH GOLOC +1 # STORE THE BB INFORMATION
060725,000210:
060726,000211: 01,3663 10000 CCS A # IS IT A JOB OR IS IT TIMED
060727,000212: 01,3664 24000 INCR A # POSITIVE, MUST BE A JOB
060728,000213: 01,3665 13740 TCF ITSAJOB2
060729,000214:
060730,000215: 01,3666 24000 INCR A # MUST BE EITHER A WAITLIST OR LONGCALL
060731,000216: 01,3667 54705 TS GOLOC # LET-S STORE THE CORRECT CADR
060732,000217:
060733,000218: 01,3670 33766 CA WTLTCADR # SET UP OUR EXIT TO WAITLIST
060734,000219: 01,3671 54704 TS GOLOC -1
060735,000220:
060736,000221: 01,3672 30706 CA GOLOC +1 # NOW FIND OUT IF IT IS A WAITLIST CALL
060737,000222: 01,3673 74701 MASK BIT10 # THIS SHOULD BE ONE IF WE HAVE -BB
060738,000223: 01,3674 10000 CCS A # FOR THAT MATTER SO SHOULD BE BITS 9,8,7,
060739,000224: # 6,5, AND LAST BUT NOT LEAST (PERHAPS NOT
060740,000225: # IN IMPORTANCE ANYWAY. BIT 4
060741,000226: 01,3675 13733 TCF ITSWTLST # IT IS A WAITLIST CALL
060742,000227:
060743,000228: 01,3676 50156 NDX POINTER # OBTAIN THE ORIGINAL DELTA T
060744,000229: 01,3677 32000 CA PRDTTAB # ADDRESS FOR THIS LONGCALL
060745,000230:
060746,000231: 01,3700 15376 TCF ITSLGCL1 # NOW GO GET THE DELTA TIME
060747,000232:
060748,000233: # ***** THIS MUST BE IN FIXED FIXED *****
060749,000234:
060750,000235: 5376 BLOCK 02
060751,000236: 4000 SETLOC FFTAG2
060752,000237: 4000 BANK
060753,000238:
060754,000239: 5376 COUNT 02/RSROU
060755,000240:
060756,000241: 5376 22706 ITSLGCL1 LXCH GOLOC +1 # OBTAIN THE CORRECT E BANK
060757,000242: 5377 22006 LXCH BB
060758,000243: 5400 22706 LXCH GOLOC +1 # AND PRESERVE OUR E AND F BANKS
060759,000244:
060760,000245: 5401 00006 EXTEND # GET THE DELTA TIME
060761,000246: 5402 50000 NDX A
060762,000247: 5403 30001 DCA 0
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Page 1386 |
060764,000249: 5404 22706 LXCH GOLOC +1 # RESTORE OUR E AND F BANK
060765,000250: 5405 22006 LXCH BB # RESTORE THE TASKS E AND F BANKS
060766,000251: 5406 22706 LXCH GOLOC +1 # AND PRESERVE OUR L
060767,000252: 5407 13701 TCF ITSLGCL2 # NOW LET:S PROCESS THIS LONGCALL
060768,000253:
060769,000254: # ***** YOU MAY RETURN TO SWITCHED FIXED *****
060770,000255:
060771,000256: 01,3701 BANK 01
060772,000257: 01,2000 SETLOC RESTART
060773,000258: 01,2000 BANK
060774,000259:
060775,000260: 01,3701 COUNT 01/RSROU
060776,000261: 01,3701 53140 ITSLGCL2 DXCH LONGTIME
060777,000262:
060778,000263: 01,3702 00006 EXTEND # CALCULATE TIME LEFT
060779,000264: 01,3703 40025 DCS TIME2
060780,000265: 01,3704 21140 DAS LONGTIME
060781,000266: 01,3705 00006 EXTEND
060782,000267: 01,3706 31136 DCA LONGBASE
060783,000268: 01,3707 21140 DAS LONGTIME
060784,000269:
060785,000270: 01,3710 11137 CCS LONGTIME # FIND OUT HOW THIS SHOULD BE RESTARTED
060786,000271: 01,3711 13721 TCF LONGCLCL
060787,000272: 01,3712 13714 TCF +2
060788,000273: 01,3713 13607 TCF IMEDIATE -3
060789,000274: 01,3714 11140 CCS LONGTIME +1
060790,000275: 01,3715 13721 TCF LONGCLCL
060791,000276: 01,3716 13717 NOOP # CAN:T GET HERE *********
060792,000277: 01,3717 13607 TCF IMEDIATE -3
060793,000278: 01,3720 13612 TCF IMEDIATE
060794,000279:
060795,000280: 01,3721 33764 LONGCLCL CA LGCLCADR # WE WILL GO TO LONGCALL
060796,000281: 01,3722 54704 TS GOLOC -1
060797,000282:
060798,000283: 01,3723 00006 EXTEND # PREPARE OUR ENTRY TO LONGCALL
060799,000284: 01,3724 31140 DCA LONGTIME
060800,000285: 01,3725 00704 TC GOLOC -1
060801,000286:
060802,000287: 01,3726 33766 ITSLNGCL CA WTLTCADR # ASSUME IT WILL GO TO WAITLIST
060803,000288: 01,3727 54704 TS GOLOC -1
060804,000289:
060805,000290: 01,3730 50155 NDX TEMP2G
060806,000291: 01,3731 41054 CS PHSPRDT1 # GET THE DELTA T ADDRESS
060807,000292:
060808,000293: 01,3732 15376 TCF ITSLGCL1 # NOW GET THE DELTA TIME
060809,000294:
060810,000295: 01,3733 40706 ITSWTLST CS GOLOC +1 # CORRECT THE BBCON INFORMATION
060811,000296: 01,3734 54706 TS GOLOC +1
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Page 1387 |
060813,000298: 01,3735 50156 NDX POINTER # GET THE DT AND FIND OUT IF IT WAS STORED
060814,000299: 01,3736 32000 CA PRDTTAB # DIRECTLY OR INDIRECTLY
060815,000300:
060816,000301: 01,3737 13566 TCF TIMETEST # FIND OUT HOW THE TIME IS STORED
060817,000302:
060818,000303: 01,3740 56705 ITSAJOB2 XCH GOLOC # STORE THE CADR
060819,000304:
060820,000305: 01,3741 50156 NDX POINTER # ADD THE PRIORITY AND LET:S GO
060821,000306: 01,3742 32000 CA PRDTTAB
060822,000307:
060823,000308: 01,3743 13631 TCF CHKNOVAC
060824,000309:
060825,000310: 01,3744 30157 ITSEVEN CA TEMPSWCH # SET UP FOR EITHER THE SECOND PART OF THE
060826,000311: 01,3745 54707 TS GOLOC +2 # TABLE, OR A RETURN FOR THE NEXT GROUP
060827,000312:
060828,000313: 01,3746 50155 NDX TEMP2G # SET UP POINTER FOR OUR LOCATION WITHIN
060829,000314: 01,3747 32000 CA SIZETAB # THE TABLE
060830,000315: 01,3750 60154 AD TEMPPHS # THIS MAY LOOK BAD BUT LET:S SEE YOU DO
060831,000316: 01,3751 60154 AD TEMPPHS # BETTER IN TIME OR NUMBERR OF LOCATIONS
060832,000317: 01,3752 60154 AD TEMPPHS
060833,000318: 01,3753 54156 TS POINTER
060834,000319:
060835,000320: 01,3754 13657 TCF CONTBL2 # NOW PROCESS WHAT IS IN THE TABLE
060836,000321:
060837,000322: 01,3755 36214 PHSPART2 CA THREE # SET THE POINTER FOR THE SECOND HALF OF
060838,000323: 01,3756 26156 ADS POINTER # THE TABLE
060839,000324:
060840,000325: 01,3757 33557 CA RTRNCADR # THIS WILL BE OUR LAST TIME THROUGH THE
060841,000326: 01,3760 54707 TS GOLOC +2 # EVEN TABLE, SO AFTER IT GET THE NEXT
060842,000327: # GROUP
060843,000328: 01,3761 13657 TCF CONTBL2 # SO LET:S GET THE SECOND ENTRY IN THE TBL
060844,000329:
060845,000330: 01,3762 0154 TEMPPHS EQUALS MPAC
060846,000331: 01,3762 0155 TEMP2G EQUALS MPAC +1
060847,000332: 01,3762 0156 POINTER EQUALS MPAC +2
060848,000333: 01,3762 0157 TEMPSWCH EQUALS MPAC +3
060849,000334: 01,3762 0705 GOLOC EQUALS VAC5 +20D
060850,000335: 01,3762 7715 MINUS2 EQUALS NEG2
060851,000336: 01,3762 6043 OCT177 EQUALS LOW7
060852,000337:
060853,000338: 01,3762 03755 PHS2CADR GENADR PHSPART2
060854,000339: 01,3763 03533 PRT2CADR GENADR GETPART2
060855,000340: 01,3764 05231 LGCLCADR GENADR LONGCALL
060856,000341: 01,3765 05042 FVACCADR GENADR FINDVAC
060857,000342: 01,3766 05140 WTLTCADR GENADR WAITLIST
060858,000343: 01,3767 05027 NOVACADR GENADR NOVAC
060859,000344:
060860,000345:
060861,000346:
060862,000347:
End of include-file RESTARTS_ROUTINE.agc. Parent file is MAIN.agc