Source Code
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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, 1968Note that the date is the date of the printout, not the date of the program revision. |
061622,000002: ## Copyright: Public domain.
061623,000003: ## Filename: SERVICE_ROUTINES.agc
061624,000004: ## Purpose: Part of the source code for Colossus build 237.
061625,000005: ## This is for the Command Module's (CM) Apollo Guidance
061626,000006: ## Computer (AGC), for Apollo 8.
061627,000007: ## Assembler: yaYUL
061628,000008: ## Contact: Jim Lawton <jim DOT lawton AT gmail DOT com>
061629,000009: ## Website: www.ibiblio.org/apollo/index.html
061630,000010: ## Page Scans: www.ibiblio.org/apollo/ScansForConversion/Colossus237/
061631,000011: ## Mod history: 2011-04-17 JL Adapted from corresponding Colossus 249 file.
061632,000012: ## 2017-01-01 RSB Proofed comment text using octopus/ProoferComments,
061633,000013: ## and fixed errors found.
061634,000014:
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Page 1449 |
061636,000016: 7717 BLOCK 3
061637,000017: 6000 SETLOC FFTAG6
061638,000018: 6000 BANK
061639,000019: 7717 COUNT 03/FLAG
061640,000020:
061641,000021: 7717 54001 UPENT2 TS L # WHICH FLAGWORD IS IT
061642,000022: 7720 74716 MASK OCT7
061643,000023: 7721 56001 XCH L # SAVE IN L FOR INDEXING
061644,000024:
061645,000025: 7722 75630 MASK OCT77770 # OBTAIN THE BIT INFORMATION
061646,000026: 7723 00004 INHINT # PREVENT INTERUPTS
061647,000027: 7724 54061 TS ITEMP1 # STORE THE BIT INFORMATION TEMPORARIALY
061648,000028:
061649,000029: 7725 50001 NDX L
061650,000030: 7726 40074 CS FLAGWRD0
061651,000031: 7727 70061 MASK ITEMP1
061652,000032: 7730 50001 NDX L
061653,000033: 7731 26074 ADS FLAGWRD0
061654,000034: 7732 00003 RELINT # RELEASE INTERUPT INHIBIT
061655,000035:
061656,000036: 7733 24002 INCR Q # OBTAIN THE CORRECT RETURN ADDRESS
061657,000037: 7734 00002 TC Q # RETURN
061658,000038:
061659,000039: 7735 54001 DOWNENT2 TS L # WHICH FLAGWORD IS IT
061660,000040: 7736 74716 MASK OCT7
061661,000041: 7737 56001 XCH L # SAVE IN L FOR INDEXING
061662,000042:
061663,000043: 7740 75630 MASK OCT77770 # OBTAIN THE BIT INFORMATION
061664,000044: 7741 40000 COM # START TO PROCESS THE INFORMATION
061665,000045:
061666,000046: 7742 00004 INHINT # PREVENT INTERUPTS
061667,000047: 7743 50001 NDX L
061668,000048: 7744 70074 MASK FLAGWRD0
061669,000049: 7745 50001 NDX L
061670,000050: 7746 54074 TS FLAGWRD0
061671,000051: 7747 00003 RELINT # RELEASE INTERUPT INHIBIT
061672,000052:
061673,000053: 7750 24002 INCR Q # OBTAIN THE CORRECT RETURN ADDRESS
061674,000054: 7751 00002 TC Q # RETURN
061675,000055:
061676,000056: 7752 4716 OCT7 EQUALS SEVEN
061677,000057: 10,3671 BANK 10
061678,000058:
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Page 1450 |
061680,000060: # UPFLAG AND DOWNFLAG ARE ENTIRELY GENERAL FLAG SETTING AND CLEARING SUBROUTINES. USING THEM, WHETHER OR
061681,000061: # NOT IN INTERRUPT, ONE MAY SET OR CLEAR ANY SINGLE, NAMED BIT IN ANY ERASABLE REGISTER, SUBJECT OF COURSE TO
061682,000062: # EBANK SETTING. A "NAMED" BIT, AS THE WORD IS USED HERE, IS ANY BIT WITH A NAME FORMALLY ASSIGNED BY THE YUL
061683,000063: # ASSEMBLER.
061684,000064:
061685,000065: # AT PRESENT THE ONLY NAMED BITS ARE THOSE IN THE FLAGWORDS. ASSEMBLER CHANGES WILL MAKE IT POSSIBLE TO
061686,000066: # NAME ANY BIT IN ERASABLE MEMORY.
061687,000067:
061688,000068: # CALLING SEQUENCES ARE AS FOLLOWS:-
061689,000069:
061690,000070: # TC UPFLAG TC DOWNFLAG
061691,000071: # ADRES NAME OF FLAG ADRES NAME OF FLAG
061692,000072:
061693,000073: # RETURN IS TO THE LOCATION FOLLOWING THE "ADRES" ABOUT .58 MS AFTER THE "TC".
061694,000074:
061695,000075: # UPON RETURN A CONTAINS THE CURRENT FLAGWRD SETTING.
061696,000076:
061697,000077: 5435 BLOCK 02
061698,000078: 4000 SETLOC FFTAG1
061699,000079: 4000 BANK
061700,000080: 5435 COUNT* $$/FLAG
061701,000081:
061702,000082: 5435 30002 UPFLAG CA Q
061703,000083: 5436 05453 TC DEBIT
061704,000084: 5437 40000 COM # +(15 - BIT)
061705,000085: 5440 00006 EXTEND
061706,000086: 5441 04001 ROR LCHAN # SET BIT
061707,000087: 5442 50061 COMFLAG INDEX ITEMP1
061708,000088: 5443 54074 TS FLAGWRD0
061709,000089: 5444 22063 LXCH ITEMP3
061710,000090: 5445 00003 RELINT
061711,000091: 5446 00001 TC L
061712,000092:
061713,000093:
061714,000094: 5447 30002 DOWNFLAG CA Q
061715,000095: 5450 05453 TC DEBIT
061716,000096: 5451 70001 MASK L # RESET BIT
061717,000097: 5452 15442 TCF COMFLAG
061718,000098:
061719,000099:
061720,000100: 5453 64712 DEBIT AD ONE # GET DE BITS
061721,000101: 5454 00004 INHINT
061722,000102: 5455 54063 TS ITEMP3
061723,000103: 5456 34721 CA LOW4 # DEC15
061724,000104: 5457 54061 TS ITEMP1
061725,000105: 5460 50063 INDEX ITEMP3
061726,000106: 5461 27777 CA 0 -1 # ADRES
061727,000107: 5462 54001 TS L
061728,000108: 5463 34714 CA ZERO
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Page 1451 |
061730,000110: 5464 00006 EXTEND
061731,000111: 5465 10061 DV ITEMP1 # A = FLAGWRD, L = (15 - BIT)
061732,000112: 5466 52062 DXCH ITEMP1
061733,000113: 5467 50061 INDEX ITEMP1
061734,000114: 5470 30074 CA FLAGWRD0
061735,000115: 5471 54001 TS L # CURRENT STATE
061736,000116: 5472 50062 INDEX ITEMP2
061737,000117: 5473 44674 CS BIT15 # -(15 - BIT)
061738,000118: 5474 00002 TC Q
061739,000119:
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Page 1452 |
061741,000121: # DELAYJOB- A GENERAL ROUTINE TO DELAY A JOB A SPECIFIC AMOUNT OF TIME BEFORE PICKING UP AGAIN.
061742,000122:
061743,000123: # ENTRANCE REQUIREMENTS...
061744,000124: # CAF DT DELAY JOB FOR DT CENTISECS
061745,000125: # TC BANKCALL
061746,000126: # CADR DELAYJOB
061747,000127:
061748,000128: 06,3651 BANK 06
061749,000129: 00,2000 SETLOC DLAYJOB
061750,000130: 00,2000 BANK
061751,000131:
061752,000132: # THIS MUST REMAIN IN BANK 0 *****************************************
061753,000133: 00,3730 COUNT 00/DELAY
061754,000134:
061755,000135: 00,3730 00004 DELAYJOB INHINT
061756,000136: 00,3731 54002 TS Q # STORE DELAY DT IN Q FOR DLY -1 IN
061757,000137:
061758,000138: 00,3732 36214 CAF DELAYNUM # WAITLIST
061759,000139: 00,3733 54070 DELLOOP TS RUPTREG1
061760,000140: 00,3734 50000 INDEX A
061761,000141: 00,3735 31141 CA DELAYLOC # IS THIS DELAYLOC AVAILABLE
061762,000142: 00,3736 00006 EXTEND
061763,000143: 00,3737 13744 BZF OK2DELAY # YES
061764,000144:
061765,000145: 00,3740 10070 CCS RUPTREG1 # NO, TRY NEXT DELAYLOC
061766,000146: 00,3741 13733 TCF DELLOOP
061767,000147:
061768,000148: 00,3742 05604 TC BAILOUT # NO AVAILABLE LOCS AVAILABLE.
061769,000149: 00,3743 01104 OCT 1104
061770,000150:
061771,000151: 00,3744 33764 OK2DELAY CA TCSLEEP # SET WAITLIST IMMEDIATE RETURN
061772,000152: 00,3745 54061 TS WAITEXIT
061773,000153:
061774,000154: 00,3746 30004 CA FBANK
061775,000155: 00,3747 60070 AD RUPTREG1 # STORE BBANK FOR TASK CALL
061776,000156: 00,3750 54001 TS L
061777,000157:
061778,000158: 00,3751 33765 CAF WAKECAD # STORE CADR FOR TASK CALL
061779,000159: 00,3752 15146 TCF DLY2 -1 # DLY IS IN WAITLIST ROUTINE
061780,000160:
061781,000161: 00,3753 04604 TCGETCAD TC MAKECADR # GET CALLERS FCADR
061782,000162:
061783,000163: 00,3754 50070 INDEX RUPTREG1
061784,000164: 00,3755 55141 TS DELAYLOC # SAVE DELAY CADRS
061785,000165:
061786,000166: 00,3756 05070 TC JOBSLEEP
061787,000167:
061788,000168: 00,3757 34714 WAKER CAF ZERO
061789,000169: 00,3760 50006 INDEX BBANK
061790,000170: 00,3761 57141 XCH DELAYLOC # MAKE DELAYLOC AVAILABLE
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Page 1453 |
061792,000172: 00,3762 05074 TC JOBWAKE
061793,000173:
061794,000174: 00,3763 05213 TC TASKOVER
061795,000175:
061796,000176: 00,3764 03751 TCSLEEP GENADR TCGETCAD -2
061797,000177: 00,3765 03757 WAKECAD GENADR WAKER
061798,000178:
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Page 1454 |
061800,000180: # GENTRAN, A BLOCK TRANSFER ROUTINE.
061801,000181:
061802,000182: # WRITTEN BY D. EYLES
061803,000183: # MOD 1 BY KERNAN UTILITYM REV 17 11/18/67
061804,000184:
061805,000185: # MOD 2 BY SCHULENBERG (REMOVE RELINT) SKIPPER REV 4 2/28/68
061806,000186:
061807,000187: # THIS ROUTINE IS USEFULL FOR TRANSFERING N CONSECUTIVE ERASABLE OR FIXED QUANTITIES TO SOME OTHER N
061808,000188: # CONSECUTIVE ERASABLE LOCATIONS. IF BOTH BLOCKS OF DATA ARE IN SWITCHABLE EBANKS, THEY MUST BE IN THE SAME ONE.
061809,000189:
061810,000190: # GENTRAN IS CALLABLE IN A JOB AS WELL AS A RUPT. THE CALLING SEQUENCE IS:
061811,000191:
061812,000192: # I CA N-1 # OF QUANTITIES MINUS ONE.
061813,000193: # I +1 TC GENTRAN IN FIXED-FIXED.
061814,000194: # I +2 ADRES L STARTING ADRES OF DATA TO BE MOVED.
061815,000195: # I +3 ADRES M STARTING ADRES OF DUPLICATION BLOCK.
061816,000196: # I +4 RETURNS HERE.
061817,000197:
061818,000198: # GENTRAN TAKES 25 MCT'S (300 MICROSECONDS) PER ITEM + 5 MCT'S (60 MICS) FOR ENTERING AND EXITING.
061819,000199:
061820,000200: # A, L AND ITEMP1 ARE NOT PRESERVED.
061821,000201:
061822,000202: 5475 BLOCK 02
061823,000203: 4000 SETLOC FFTAG4
061824,000204: 4000 BANK
061825,000205:
061826,000206: 5475 0061 EBANK= ITEMP1
061827,000207:
061828,000208: 5475 COUNT* $$/TRAN
061829,000209:
061830,000210: 5475 00004 GENTRAN INHINT
061831,000211: 5476 54061 TS ITEMP1 # SAVE N-1.
061832,000212: 5477 50002 INDEX Q # C(Q) = ADRES L.
061833,000213: 5500 60000 AD 0 # ADRES (L + N - 1).
061834,000214: 5501 50000 INDEX A
061835,000215: 5502 30000 CA 0 # C(ABOVE).
061836,000216: 5503 54001 TS L # SAVE DATA.
061837,000217: 5504 30061 CA ITEMP1
061838,000218: 5505 50002 INDEX Q
061839,000219: 5506 60001 AD 1 # ADRES (M + N - 1).
061840,000220: 5507 50000 INDEX A
061841,000221: 5510 22000 LXCH 0 # STUFF IT.
061842,000222: 5511 10061 CCS ITEMP1 # LOOP UNTIL N-1 = 0.
061843,000223: 5512 15476 TCF GENTRAN +1
061844,000224: 5513 16710 TCF Q+2 # RETURN TO CALLER.
061845,000225:
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Page 1455 |
061847,000227: # B5OFF ZERO BIT 5 OF EXTVBACT, WHICH IS SET BY TESTXACT.
061848,000228:
061849,000229: # MAY BE USED AS NEEDED BY ANY EXTENDED VERB WHICH HAS DONE TESTXACT
061850,000230:
061851,000231: 5514 COUNT* $$/EXTVB
061852,000232:
061853,000233: 5514 44706 B5OFF CS BIT5
061854,000234: 5515 71044 MASK EXTVBACT
061855,000235: 5516 55044 TS EXTVBACT
061856,000236: 5517 05112 TC ENDOFJOB
061857,000237:
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Page 1456 |
061859,000239: # SUBROUTINES TO TURNOFF AND TURN ON TRACKER FAIL LIGHT.
061860,000240:
061861,000241: 5520 00004 TRFAILOF INHINT
061862,000242: 5521 47704 CS OCT40200 # TURN OFF TRACKER LIGHT
061863,000243: 5522 71036 MASK DSPTAB +11D
061864,000244: 5523 64674 AD BIT15
061865,000245: 5524 55036 TS DSPTAB +11D
061866,000246: 5525 41331 CS OPTMODES # TO INSURE THAT OCDU FAIL WILL GO ON
061867,000247: 5526 74704 MASK BIT7 # AGAIN IF IT WAS ON IN ADDITION TO
061868,000248: 5527 27331 ADS OPTMODES # TRACKER FAIL.
061869,000249:
061870,000250: 5530 00003 REQ RELINT
061871,000251: 5531 00002 TC Q
061872,000252:
061873,000253: 5532 00004 TRFAILON INHINT
061874,000254: 5533 41036 CS DSPTAB +11D # TURN ON
061875,000255: 5534 77704 MASK OCT40200
061876,000256: 5535 27036 ADS DSPTAB +11D
061877,000257: 5536 15530 TCF REQ
End of include-file SERVICE_ROUTINES.agc. Parent file is MAIN.agc