Source Code
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These source-code files were transcribed from scans made from Don Eyles's personal
copy of Luminary 069. They were scanned at archive.org's Boston
facility, and the scanning was sponsored by Onno Hommes. 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 prefixed with a single '#' symbol,
whereas comments added later are prefixed by "##" or "###". 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 Luminary 69 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:GAP: ASSEMBLE REVISION 069 OF AGC PROGRAM LUMINARY BY NASA 2021112-011 19:02 NOV. 25,1968Note that the date is the date of the printout, not the date of the program revision. |
016299,000002: ## Copyright: Public domain.
016300,000003: ## Filename: GIMBAL_LOCK_AVOIDANCE.agc
016301,000004: ## Purpose: The main source file for Luminary revision 069.
016302,000005: ## It is part of the source code for the original release
016303,000006: ## of the flight software for the Lunar Module's (LM) Apollo
016304,000007: ## Guidance Computer (AGC) for Apollo 10. The actual flown
016305,000008: ## version was Luminary 69 revision 2, which included a
016306,000009: ## newer lunar gravity model and only affected module 2.
016307,000010: ## This file is intended to be a faithful transcription, except
016308,000011: ## that the code format has been changed to conform to the
016309,000012: ## requirements of the yaYUL assembler rather than the
016310,000013: ## original YUL assembler.
016311,000014: ## Reference: p. 377
016312,000015: ## Assembler: yaYUL
016313,000016: ## Contact: Ron Burkey <info@sandroid.org>.
016314,000017: ## Website: www.ibiblio.org/apollo/index.html
016315,000018: ## Mod history: 2016-12-13 MAS Created from Luminary 99.
016316,000019: ## 2016-12-14 MAS Updated from comment-proofed Luminary 99 version.
016317,000020: ## 2017-01-13 RRB Updated for Luminary 69.
016318,000021: ## 2017-01-27 RSB Proofed comment text using octopus/prooferComments
016319,000022: ## and fixed errors found.
016320,000023:
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Page 377 |
016322,000025: 15,2050 BANK 15
016323,000026:
016324,000027: 22,2000 SETLOC KALCMON1
016325,000028: 22,2000 BANK
016326,000029:
016327,000030: # DETECTING GIMBAL LOCK
016328,000031: 22,2744 22,2744 LOCSKIRT EQUALS NOGIMLOC
016329,000032:
016330,000033: 22,2744 77614 NOGIMLOC SET
016331,000034: 22,2745 01074 CALCMAN3
016332,000035: 22,2746 70740 WCALC LXC,1 DLOAD*
016333,000036: 22,2747 01325 RATEINDX # CHOOSE THE DESIRED MANEUVER RATE
016334,000037: 22,2750 04772 ARATE,1 # FROM A LIST OF FOUR
016335,000038: 22,2751 45002 SR4 CALL # COMPUTE THE INCREMENTAL ROTATION MATRIX
016336,000039: 22,2752 44527 DELCOMP # DEL CORRESPONDING TO A 1 SEC ROTATION
016337,000040: # ABOUT COF
016338,000041: 22,2753 74343 DLOAD* VXSC
016339,000042: 22,2754 04772 ARATE,1
016340,000043: 22,2755 03267 COF
016341,000044: 22,2756 17324 STODL BRATE # COMPONENT MANEUVER RATES 45 DEG/SEC
016342,000045: 22,2757 03334 AM
016343,000046: 22,2760 55605 DMP DDV*
016344,000047: 22,2761 05002 ANGLTIME
016345,000048: 22,2762 04772 ARATE,1
016346,000049: 22,2763 77661 SR
016347,000050: 22,2764 20606 5
016348,000051: 22,2765 03332 STORE TM # MANEUVER EXECUTION TIME SCALED AS T2
016349,000052: 22,2766 77614 SETGO
016350,000053: 22,2767 01035 CALCMAN2 # D(OFF) = CONTINUE MANEUVER
016351,000054: 22,2770 45010 NEWANGL +1 # 1(ON) = START MANEUVER
016352,000055:
016353,000056: # THE FOUR SELECTABLE FREE FALL MANEUVER RATES SELECTED BY
016354,000057: # LOADING RATEINDX WITH 0, 2, 4, 6, RESPECTIVELY
016355,000058:
016356,000059: 22,2771 00221 24255 ARATE 2DEC .0088888888 # = 0.2 DEG/SEC $ 22.5 DEG/SEC
016357,000060:
016358,000061: 22,2773 00554 02660 2DEC .0222222222 # = 0.5 DEG/SEC $ 22.5 DEG/SEC
016359,000062:
016360,000063: 22,2775 02660 13301 2DEC .0888888888 # = 2.0 DEG/SEC $ 22.5 DEG/SEC
016361,000064:
016362,000065: 22,2777 16161 30707 2DEC .4444444444 # = 10.0 DEG/SEC $ 22.5 DEG/SEC
016363,000066:
016364,000067: 22,3001 00003 04000 ANGLTIME 2DEC .0001907349 # = 100B-19 FUDGE FACTOR TO CONVERT
016365,000068: # MANEUVER ANGLE TO MANEUVER TIME
016366,000069:
016367,000070:
End of include-file GIMBAL_LOCK_AVOIDANCE.agc. Parent file is MAIN.agc