Source Code

These source-code files were transcribed from scans made from Don Eyles's personal copy of BURST120 (SUNBURST 120). They were scanned at archive.org's Boston facility, and the scanning was sponsored by Mike Stewart. The code was transcribed from these scans by a team of volunteers who are referenced in the program comments. Comments from the original source code are in ALL-CAPS, whereas comments added later in transcription are in Mixed-Case. In some cases, where similar code blocks exist in previously-transcribed AGC programs (primarily Luminary 99, from Apollo 11) those code blocks were used as a starting point and then corrected to agree with the BURST120 scans. The full scans are available at the Virtual AGC project's collection at archive.org, while more-convenient reduced-size (but reduced-quality) images are available at the main Virtual AGC website. Report any errors noted by creating an issue report at the Virtual AGC project's GitHub repository. Notations on the program listing read, in part:

	YUL SYSTEM FOR AGC: REVISION 0 OF PROGRAM BURST120 
	BY NASA 2021106-031 DEC 7, 1967

	THIS LISTING IS A COPY OF A VERSION OF THE PROGRAM INTENDED 
	FOR USE IN THE ON-BOARD PRIMARY GUIDANCE COMPUTER IN THE 
	UNMANNED FLIGHT OF APOLLO LUNAR MODULE 1 --- THE AS206 MISSION.
Note that the date is the date of the printout, not the date of the program revision.

035420,000002:                                                                                                  ## Copyright:    Public domain.
035421,000003:                                                                                                  ## Filename:     TUMBLE_MONITOR.agc
035422,000004:                                                                                                  ## Purpose:      A module for revision 0 of BURST120 (Sunburst). It 
035423,000005:                                                                                                  ##               is part of the source code for the Lunar Module's
035424,000006:                                                                                                  ##               (LM) Apollo Guidance Computer (AGC) for Apollo 5.
035425,000007:                                                                                                  ## Assembler:    yaYUL
035426,000008:                                                                                                  ## Contact:      Ron Burkey <info@sandroid.org>.
035427,000009:                                                                                                  ## Website:      www.ibiblio.org/apollo/index.html
035428,000010:                                                                                                  ## Mod history:  2016-09-30 RSB  Created draft version.
035429,000011:                                                                                                  ##               2016-10-29 MAS  Transcribed.
035430,000012:                                                                                                  ##               2016-12-06 RSB  Comment-proofing via octopus/ProoferComments;
035431,000013:                                                                                                  ##                               changes were made.
035432,000014: 

Page 832

035434,000016:                                                                                                  #  PROGRAM DETECTS SPIN ABOUT NAV.AXES AND SETS BIT 13 OF FLAGWORD1 ON IF SPIN IS IN EXCESS OF 2.99 DEGREES/SEC .
035435,000017:                                                                                                  #  NO CONTROL ACTION IS EXERTED . TO DISCONTINUE MONITORING , TURN BIT 14  OF FLAGWORD1 OFF . TO INITIATE MONITOR ,
035436,000018:                                                                                                  #  SET UP WAITLIST CALL FOR TUMTASK. IT IS ASSUMED THAT THE IMU,S ARE IN   FINE ALIGN .
035437,000019: 
035438,000020: 
035439,000021: 
035440,000022:                                                                                                  #  NAME=                           DATE=
035441,000023:                                                                                                  #    TUMBLE MONITOR                  29 AUGUST 1966
035442,000024:                                                                                                  #  PROGRAMMER=                     REVISIONS=
035443,000025:                                                                                                  #    G.MANSBACH EXT-182              NANSTONE/2
035444,000026:                                                                                                  #                                    NANSTONE/7
035445,000027:                                                                                                  #                                    NANSTONE/15   10/27/66
035446,000028:                                                                                                  #                                    NANSTONE/3    11/12/66
035447,000029:                                                                                                  #  CALLING SEQUENCE=               SUBROUTINES CALLED=
035448,000030:                                                                                                  #           CAF    (DT)              FLAG1UP
035449,000031:                                                                                                  #           TC     WAITLIST          FLAG1DOWN
035450,000032:                                                                                                  #           EBANK= OMEGA
035451,000033:                                                                                                  #           2CADR  TUMTASK
035452,000034:                                                                                                  #  NORMAL EXIT MODES=              ABORT MODE=
035453,000035:                                                                                                  #           TC     TASKOVER          TURN BIT 14 OF FLAGWORD1 OFF
035454,000036:                                                                                                  #  OUTPUT=
035455,000037:                                                                                                  #    SET BIT 13 OF FLAGWORD1 ON/OFF
035456,000038:                                                                                                  #  DEBRIS=
035457,000039:                                                                                                  #    PCDUY,PCDUZ,PCDUX,DCDUY,DCDUZ,OMEGA
035458,000040: 30,2470                                           BANK     30                                    
035459,000041: 30,2470  E6,1422                                  EBANK=   OMEGA                                 
035460,000042:                                                                                                  #  INITIALIZATION ROUTINE FOR TUMBLE
035461,000043:                                                                                                  #  MONITOR
035462,000044: 
035463,000045: 30,2470           04161        TUMTASK            TC       PHASCHNG                              #  IMMEDIATE RECALL
035464,000046: 30,2471           05013                           OCT      05013                                 #  *TUMTASK*
035465,000047: 30,2472           77777                           OCT      77777                                 
035466,000048: 30,2473           06051                           TC       FLAG1UP                               #  TURN TUMBLE MONITOR ON
035467,000049: 30,2474           20000                           OCT      20000                                 
035468,000050: 30,2475           02547                           TC       RESET                                 
035469,000051: 30,2476           05727                           TC       TASKOVER                              
035470,000052: 
035471,000053: 
035472,000054: 30,2477           37746        TMTSK              CA       BIT14                                 
035473,000055: 30,2500           70075                           MASK     FLAGWRD1                              #  IS TUMBLE MONITOR STILL NEEDED
035474,000056: 30,2501           00006                           EXTEND                                         
035475,000057: 30,2502           12542                           BZF      EOTUM                                 #  IT IS NOT.  DISCONTINUE MONITORING
035476,000058: 
035477,000059: 30,2503           02547                           TC       RESET                                 #  IT IS.
035478,000060:                                                                                                  #  COMPUTE ROTATION RATE ABOUT PILOT AXES
035479,000061:                                                                                                  #  USING OUTPUT OF *TRANSFORMATION MATRIX
035480,000062:                                                                                                  #  CALCULATION* OF *TRUPT PROGRAM*
035481,000063: 
035482,000064:                                                                                                  #  COMPUTE
035483,000065:                                                                                                  #         * OMEGAX *   *     *   * DCDUY *

Page 833

035485,000067:                                                                                                  #         * OMEGAY * = * M   * X * DCDUZ *
035486,000068:                                                                                                  #         * OMEGAZ *   *  GP *   *+DCDUX *
035487,000069: 
035488,000070: 30,2504           55422                           TS       OMEGA                                 #  COMPUTE OMEGAX
035489,000071: 30,2505           31404                           CA       M11                                   
035490,000072: 30,2506           02526                           TC       EVAL                                  
035491,000073: 30,2507           31401                           CA       M22                                   #  COMPUTE OMEGAY
035492,000074: 30,2510           00006                           EXTEND                                         
035493,000075: 30,2511           71420                           MP       DCDUZ                                 
035494,000076: 30,2512           55422                           TS       OMEGA                                 
035495,000077: 30,2513           31405                           CA       M21                                   
035496,000078: 30,2514           02526                           TC       EVAL                                  
035497,000079: 30,2515           31403                           CA       M32                                   #  COMPUTE OMEGAZ
035498,000080: 30,2516           00006                           EXTEND                                         
035499,000081: 30,2517           71420                           MP       DCDUZ                                 
035500,000082: 30,2520           55422                           TS       OMEGA                                 
035501,000083: 30,2521           31406                           CA       M31                                   
035502,000084: 30,2522           02526                           TC       EVAL                                  
035503,000085:                                                                                                  #  NO TUMBLE NOTED
035504,000086: 30,2523           06067                           TC       FLAG1DWN                              #  REMOVE TUMBLE FLAG
035505,000087: 30,2524           10000                           OCT      10000                                 
035506,000088: 30,2525           05727                           TC       TASKOVER                              
035507,000089: 30,2526           00006        EVAL               EXTEND                                         #  COMPLETE OMEGA CALCULATION
035508,000090: 30,2527           71416                           MP       DCDUY                                 
035509,000091: 30,2530           61422                           AD       OMEGA                                 #  SCALE FACTOR OF PI
035510,000092:                                                                                                  #  EVALUATE TUMBLE RATE
035511,000093: 30,2531           00006                           EXTEND                                         #  SET ALL VALUES NEG.
035512,000094: 30,2532           62534                           BZMF     +2                                    
035513,000095: 30,2533           40000                           CS       A                                     
035514,000096: 30,2534           62546                           AD       CRIT                                  #  CAUSE UNDERFLOW IF OMEGA IS GREATER THAN
035515,000097: 30,2535           54000                           OVSK                                           #  OR = TO 2.99 DEGREES/SEC
035516,000098: 30,2536           00002                           RETURN                                         #  NO TUMBLE . EVALUATE NEXT AXIS
035517,000099: 
035518,000100:                                                                                                  #  EXCESSIVE TUMBLE NOTED ABOUT AN AXIS
035519,000101: 30,2537           06051                           TC       FLAG1UP                               #  SET TUMBLE FLAG AND DISCONTINUE CALCS.
035520,000102: 30,2540           10000                           OCT      10000                                 
035521,000103: 30,2541           05727                           TC       TASKOVER                              
035522,000104: 30,2542           04161        EOTUM              TC       PHASCHNG                              
035523,000105: 30,2543           00003                           OCT      3                                     
035524,000106: 30,2544           05727                           TC       TASKOVER                              
035525,000107: 30,2545           00144        1SECTM             DEC      100        B-14                       #  1 SECOND
035526,000108: 30,2546           40417        CRIT               OCT      40417                                 #  NEGMAX + 00417   421 = 2.99 DEGREES
035527,000109: 
035528,000110: 
035529,000111:                                                                                                  #  RECALL MONITOR IN
035530,000112:                                                                                                  #     1 SECOND
035531,000113: 30,2547           00006        RESET              EXTEND                                         
035532,000114: 30,2550           23422                           QXCH     OMEGA                                 
035533,000115: 30,2551           32545                           CA       1SECTM                                
035534,000116: 30,2552           05663                           TC       WAITLIST                              

Page 834

035536,000118: 30,2553  E6,1422                                  EBANK=   OMEGA                                 
035537,000119: 30,2553           02477 60066                     2CADR    TMTSK                                 
035538,000120:                                                                                                  #  STORE PRESENT CDU(X,Y,Z) AND
035539,000121:                                                                                                  #  COMPUTE DELTA(CDU(X,Y,Z)/SEC =
035540,000122:                                                                                                  #  DCDU(X,Y,Z)
035541,000123: 30,2555           30033                           CA       CDUY                                  #  FOR Y-AXIS
035542,000124: 30,2556           57412                           XCH      PCDUY                                 #  STORE PRESENT VALUE AND RECOVER PREVIOUS
035543,000125: 30,2557           00006                           EXTEND                                         
035544,000126: 30,2560           20033                           MSU      CDUY                                  
035545,000127: 30,2561           55416                           TS       DCDUY                                 #  = CDUX(T-1)-CDUX(T)
035546,000128: 30,2562           30034                           CA       CDUZ                                  #  FOR Z-AXIS
035547,000129: 30,2563           57413                           XCH      PCDUZ                                 
035548,000130: 30,2564           00006                           EXTEND                                         
035549,000131: 30,2565           20034                           MSU      CDUZ                                  
035550,000132: 30,2566           55420                           TS       DCDUZ                                 
035551,000133: 30,2567           30032                           CA       CDUX                                  #  FOR X-AXIS
035552,000134: 30,2570           57411                           XCH      PCDUX                                 
035553,000135: 30,2571           00006                           EXTEND                                         
035554,000136: 30,2572           20032                           MSU      CDUX                                  
035555,000137: 30,2573           01422                           TC       OMEGA                                 

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