Source Code
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These source-code files were obtained by digitally photographing
an Artemis 72 program listing from a private collection and then
modifying pre-existing Comanche 55 (Apollo 11) source files to
incorporate changes. Note that the page images
presented online are of reduced quality, and that additional images
may be 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 072 OF AGC PROGRAM ARTEMIS BY NASA 2021114-011 11:40 FEB. 26, 1971 THIS AGC PROGRAM SHALL ALSO BE REFERRED TO AS COLOSSUS 3 THIS PROGRAM IS INTENDED FOR USE IN THE CM AS SPECIFIED IN REPORT R-577. THIS PROGRAM WAS PREPARED UNDER OSR PROJECT 55-23890, SPONSORED BY THE MANNED SPACECRAFT CENTER OF THE NATIONAL AERONAUTICS AND SPACE ADMINISTRATION THROUGH CONTRACT NAS 9-4065 WITH THE CHARLES STARK DRAPER LABORATORY, MASSACHUSETTS INSTITUTE OF TECHNOLOGY, CAMBRIDGE, MASS. |
018397,000002: # Copyright: Public domain.
018398,000003: # Filename: GIMBAL_LOCK_AVOIDANCE.agc
018399,000004: # Purpose: Part of the source code for Artemis (i.e., Colossus 3),
018400,000005: # build 072. This is for the Command Module's (CM)
018401,000006: # Apollo Guidance Computer (AGC), we believe for
018402,000007: # Apollo 15-17.
018403,000008: # Assembler: yaYUL
018404,000009: # Contact: Sergio Navarro <sergionavarrog@gmail.com>
018405,000010: # Website: www.ibiblio.org/apollo/index.html
018406,000011: # Page scans: www.ibiblio.org/apollo/ScansForConversion/Artemis072/
018407,000012: # Mod history: 2009-08-19 SN Adapted from corresponding Comanche 055 file.
018408,000013: # 2009-09-04 JL Minor changes.
018409,000014: # 2010-02-20 RSB Un-##'d this header.
018410,000015:
018411,000016: # # Page 416
018412,000017:
018413,000018: 22,2000 SETLOC KALCMON1
018414,000019: 22,2000 BANK
018415,000020:
018416,000021: 22,2745 COUNT* $$/KALC
018417,000022: 22,2745 E6,1661 EBANK= BCDU
018418,000023:
018419,000024: # DETECTING GIMBAL LOCK
018420,000025: 22,2745 22,2745 LOCSKIRT EQUALS WCALC
018421,000026: 22,2745 70740 WCALC LXC,1 DLOAD*
018422,000027: 22,2746 00774 RATEINDX
018423,000028: 22,2747 05002 ARATE,1
018424,000029: 22,2750 45002 SR4 CALL # COMPUTE THE INCREMENTAL ROTATION MATRIX
018425,000030: 22,2751 44522 DELCOMP # DEL CORRESPONDING TO A 1 SEC ROTATION
018426,000031: # ABOUT COF
018427,000032: 22,2752 74343 DLOAD* VXSC
018428,000033: 22,2753 05002 ARATE,1
018429,000034: 22,2754 03343 COF
018430,000035: 22,2755 77721 MXV
018431,000036: 22,2756 05014 QUADROT
018432,000037: 22,2757 17311 STODL BRATE
018433,000038: 22,2760 03365 AM
018434,000039: 22,2761 55605 DMP DDV*
018435,000040: 22,2762 05012 ANGLTIME
018436,000041: 22,2763 05002 ARATE,1
018437,000042: 22,2764 77661 SR
018438,000043: 22,2765 20606 5
018439,000044: 22,2766 03317 STORE TM
018440,000045: 22,2767 77214 BON VLOAD
018441,000046: 22,2770 00313 CYC61FLG
018442,000047: 22,2771 71747 RCYCLR61
018443,000048: 22,2772 03311 BRATE
018444,000049: 22,2773 77761 VXSC
018445,000050: 22,2774 05036 BIASCALE
018446,000051: 22,2775 03275 STORE BIASTEMP # ATTITUDE ERROR BIAS TO PREVENT OVERSHOOT
018447,000052: # IN SYSTEM
018448,000053: 22,2776 77614 SETGO # STATE SWITCH CALCMAN2 (43D)
018449,000054: 22,2777 01035 CALCMAN2 # 0(OFF) = BYPASS STARTING PROCEDURE
018450,000055: 22,3000 45053 NEWANGL +1 # 1(ON) = START MANEUVER
018451,000056:
018452,000057:
018453,000058: 22,3001 00044 15053 ARATE 2DEC .0022222222 # = .05 DEG/SEC
018454,000059: 22,3003 00221 24255 2DEC .0088888889 # = .2 DEG/SEC
018455,000060: 22,3005 00554 02660 2DEC .0222222222 # = .5 DEG/SEC
018456,000061: 22,3007 02660 13301 2DEC .0888888889 # = 2 DEG/SEC $22.5 DEG/SEC
018457,000062: 22,3011 00003 04000 ANGLTIME 2DEC .000190735 # = 100B - 19
018458,000063: # MANEUVER ANGLE TO MANEUVER TIME
018459,000064: # # Page 417
018460,000065: 22,3013 03146 14632 QUADROT 2DEC .1 # ROTATION MATRIX FROM S/C AXES TO CONTROL
018461,000066: 22,3015 00000 00000 2DEC 0 B-28 # AXES (X ROT = -7.25 DEG)
018462,000067: 22,3017 00000 00000 2DEC 0 B-28
018463,000068: 22,3021 00000 00000 2DEC 0 B-28
018464,000069: 22,3023 03131 11275 2DEC .099200 # =(.1)COS7.25
018465,000070: 22,3025 77461 47370 2DEC -.012620 # =-(.1)SIN7.25
018466,000071: 22,3027 00000 00000 2DEC 0 B-28
018467,000072: 22,3031 00316 30407 2DEC .012620 # (.1)SIN7.25
018468,000073: 22,3033 03131 11275 2DEC .099200 # (.1)COS7.25
018469,000074: 22,3035 00004 05253 BIASCALE 2DEC .0002543132 # = (450/180)(1/0.6)(1/16384)
End of include-file GIMBAL_LOCK_AVOIDANCE.agc. Parent file is MAIN.agc