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.

035447,000002:                                                                                                  ## Copyright:    Public domain.
035448,000003:                                                                                                  ## Filename:     TUMBLE_MONITOR.agc
035449,000004:                                                                                                  ## Purpose:      A module for revision 0 of BURST120 (Sunburst). It 
035450,000005:                                                                                                  ##               is part of the source code for the Lunar Module's
035451,000006:                                                                                                  ##               (LM) Apollo Guidance Computer (AGC) for Apollo 5.
035452,000007:                                                                                                  ## Assembler:    yaYUL
035453,000008:                                                                                                  ## Contact:      Ron Burkey <info@sandroid.org>.
035454,000009:                                                                                                  ## Website:      www.ibiblio.org/apollo/index.html
035455,000010:                                                                                                  ## Mod history:  2016-09-30 RSB  Created draft version.
035456,000011:                                                                                                  ##               2016-10-29 MAS  Transcribed.
035457,000012:                                                                                                  ##               2016-12-06 RSB  Comment-proofing via octopus/ProoferComments;
035458,000013:                                                                                                  ##                               changes were made.
035459,000014: 

Page 832

035461,000016:                                                                                                  #  PROGRAM DETECTS SPIN ABOUT NAV.AXES AND SETS BIT 13 OF FLAGWORD1 ON IF SPIN IS IN EXCESS OF 2.99 DEGREES/SEC .
035462,000017:                                                                                                  #  NO CONTROL ACTION IS EXERTED . TO DISCONTINUE MONITORING , TURN BIT 14  OF FLAGWORD1 OFF . TO INITIATE MONITOR ,
035463,000018:                                                                                                  #  SET UP WAITLIST CALL FOR TUMTASK. IT IS ASSUMED THAT THE IMU,S ARE IN   FINE ALIGN .
035464,000019: 
035465,000020: 
035466,000021: 
035467,000022:                                                                                                  #  NAME=                           DATE=
035468,000023:                                                                                                  #    TUMBLE MONITOR                  29 AUGUST 1966
035469,000024:                                                                                                  #  PROGRAMMER=                     REVISIONS=
035470,000025:                                                                                                  #    G.MANSBACH EXT-182              NANSTONE/2
035471,000026:                                                                                                  #                                    NANSTONE/7
035472,000027:                                                                                                  #                                    NANSTONE/15   10/27/66
035473,000028:                                                                                                  #                                    NANSTONE/3    11/12/66
035474,000029:                                                                                                  #  CALLING SEQUENCE=               SUBROUTINES CALLED=
035475,000030:                                                                                                  #           CAF    (DT)              FLAG1UP
035476,000031:                                                                                                  #           TC     WAITLIST          FLAG1DOWN
035477,000032:                                                                                                  #           EBANK= OMEGA
035478,000033:                                                                                                  #           2CADR  TUMTASK
035479,000034:                                                                                                  #  NORMAL EXIT MODES=              ABORT MODE=
035480,000035:                                                                                                  #           TC     TASKOVER          TURN BIT 14 OF FLAGWORD1 OFF
035481,000036:                                                                                                  #  OUTPUT=
035482,000037:                                                                                                  #    SET BIT 13 OF FLAGWORD1 ON/OFF
035483,000038:                                                                                                  #  DEBRIS=
035484,000039:                                                                                                  #    PCDUY,PCDUZ,PCDUX,DCDUY,DCDUZ,OMEGA
035485,000040: 30,2470                                           BANK     30                                    
035486,000041: 30,2470  E6,1422                                  EBANK=   OMEGA                                 
035487,000042:                                                                                                  #  INITIALIZATION ROUTINE FOR TUMBLE
035488,000043:                                                                                                  #  MONITOR
035489,000044: 
035490,000045: 30,2470           04161        TUMTASK            TC       PHASCHNG                              #  IMMEDIATE RECALL
035491,000046: 30,2471           05013                           OCT      05013                                 #  *TUMTASK*
035492,000047: 30,2472           77777                           OCT      77777                                 
035493,000048: 30,2473           06051                           TC       FLAG1UP                               #  TURN TUMBLE MONITOR ON
035494,000049: 30,2474           20000                           OCT      20000                                 
035495,000050: 30,2475           02547                           TC       RESET                                 
035496,000051: 30,2476           05727                           TC       TASKOVER                              
035497,000052: 
035498,000053: 
035499,000054: 30,2477           37746        TMTSK              CA       BIT14                                 
035500,000055: 30,2500           70075                           MASK     FLAGWRD1                              #  IS TUMBLE MONITOR STILL NEEDED
035501,000056: 30,2501           00006                           EXTEND                                         
035502,000057: 30,2502           12542                           BZF      EOTUM                                 #  IT IS NOT.  DISCONTINUE MONITORING
035503,000058: 
035504,000059: 30,2503           02547                           TC       RESET                                 #  IT IS.
035505,000060:                                                                                                  #  COMPUTE ROTATION RATE ABOUT PILOT AXES
035506,000061:                                                                                                  #  USING OUTPUT OF *TRANSFORMATION MATRIX
035507,000062:                                                                                                  #  CALCULATION* OF *TRUPT PROGRAM*
035508,000063: 
035509,000064:                                                                                                  #  COMPUTE
035510,000065:                                                                                                  #         * OMEGAX *   *     *   * DCDUY *

Page 833

035512,000067:                                                                                                  #         * OMEGAY * = * M   * X * DCDUZ *
035513,000068:                                                                                                  #         * OMEGAZ *   *  GP *   *+DCDUX *
035514,000069: 
035515,000070: 30,2504           55422                           TS       OMEGA                                 #  COMPUTE OMEGAX
035516,000071: 30,2505           31404                           CA       M11                                   
035517,000072: 30,2506           02526                           TC       EVAL                                  
035518,000073: 30,2507           31401                           CA       M22                                   #  COMPUTE OMEGAY
035519,000074: 30,2510           00006                           EXTEND                                         
035520,000075: 30,2511           71420                           MP       DCDUZ                                 
035521,000076: 30,2512           55422                           TS       OMEGA                                 
035522,000077: 30,2513           31405                           CA       M21                                   
035523,000078: 30,2514           02526                           TC       EVAL                                  
035524,000079: 30,2515           31403                           CA       M32                                   #  COMPUTE OMEGAZ
035525,000080: 30,2516           00006                           EXTEND                                         
035526,000081: 30,2517           71420                           MP       DCDUZ                                 
035527,000082: 30,2520           55422                           TS       OMEGA                                 
035528,000083: 30,2521           31406                           CA       M31                                   
035529,000084: 30,2522           02526                           TC       EVAL                                  
035530,000085:                                                                                                  #  NO TUMBLE NOTED
035531,000086: 30,2523           06067                           TC       FLAG1DWN                              #  REMOVE TUMBLE FLAG
035532,000087: 30,2524           10000                           OCT      10000                                 
035533,000088: 30,2525           05727                           TC       TASKOVER                              
035534,000089: 30,2526           00006        EVAL               EXTEND                                         #  COMPLETE OMEGA CALCULATION
035535,000090: 30,2527           71416                           MP       DCDUY                                 
035536,000091: 30,2530           61422                           AD       OMEGA                                 #  SCALE FACTOR OF PI
035537,000092:                                                                                                  #  EVALUATE TUMBLE RATE
035538,000093: 30,2531           00006                           EXTEND                                         #  SET ALL VALUES NEG.
035539,000094: 30,2532           62534                           BZMF     +2                                    
035540,000095: 30,2533           40000                           CS       A                                     
035541,000096: 30,2534           62546                           AD       CRIT                                  #  CAUSE UNDERFLOW IF OMEGA IS GREATER THAN
035542,000097: 30,2535           54000                           OVSK                                           #  OR = TO 2.99 DEGREES/SEC
035543,000098: 30,2536           00002                           RETURN                                         #  NO TUMBLE . EVALUATE NEXT AXIS
035544,000099: 
035545,000100:                                                                                                  #  EXCESSIVE TUMBLE NOTED ABOUT AN AXIS
035546,000101: 30,2537           06051                           TC       FLAG1UP                               #  SET TUMBLE FLAG AND DISCONTINUE CALCS.
035547,000102: 30,2540           10000                           OCT      10000                                 
035548,000103: 30,2541           05727                           TC       TASKOVER                              
035549,000104: 30,2542           04161        EOTUM              TC       PHASCHNG                              
035550,000105: 30,2543           00003                           OCT      3                                     
035551,000106: 30,2544           05727                           TC       TASKOVER                              
035552,000107: 30,2545           00144        1SECTM             DEC      100        B-14                       #  1 SECOND
035553,000108: 30,2546           40417        CRIT               OCT      40417                                 #  NEGMAX + 00417   421 = 2.99 DEGREES
035554,000109: 
035555,000110: 
035556,000111:                                                                                                  #  RECALL MONITOR IN
035557,000112:                                                                                                  #     1 SECOND
035558,000113: 30,2547           00006        RESET              EXTEND                                         
035559,000114: 30,2550           23422                           QXCH     OMEGA                                 
035560,000115: 30,2551           32545                           CA       1SECTM                                
035561,000116: 30,2552           05663                           TC       WAITLIST                              

Page 834

035563,000118: 30,2553  E6,1422                                  EBANK=   OMEGA                                 
035564,000119: 30,2553           02477 60066                     2CADR    TMTSK                                 
035565,000120:                                                                                                  #  STORE PRESENT CDU(X,Y,Z) AND
035566,000121:                                                                                                  #  COMPUTE DELTA(CDU(X,Y,Z)/SEC =
035567,000122:                                                                                                  #  DCDU(X,Y,Z)
035568,000123: 30,2555           30033                           CA       CDUY                                  #  FOR Y-AXIS
035569,000124: 30,2556           57412                           XCH      PCDUY                                 #  STORE PRESENT VALUE AND RECOVER PREVIOUS
035570,000125: 30,2557           00006                           EXTEND                                         
035571,000126: 30,2560           20033                           MSU      CDUY                                  
035572,000127: 30,2561           55416                           TS       DCDUY                                 #  = CDUX(T-1)-CDUX(T)
035573,000128: 30,2562           30034                           CA       CDUZ                                  #  FOR Z-AXIS
035574,000129: 30,2563           57413                           XCH      PCDUZ                                 
035575,000130: 30,2564           00006                           EXTEND                                         
035576,000131: 30,2565           20034                           MSU      CDUZ                                  
035577,000132: 30,2566           55420                           TS       DCDUZ                                 
035578,000133: 30,2567           30032                           CA       CDUX                                  #  FOR X-AXIS
035579,000134: 30,2570           57411                           XCH      PCDUX                                 
035580,000135: 30,2571           00006                           EXTEND                                         
035581,000136: 30,2572           20032                           MSU      CDUX                                  
035582,000137: 30,2573           01422                           TC       OMEGA                                 

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