Source Code
![]() |
These source-code files were obtained by digitally photographing the
Colossus 237 program listing from the private collection of original
AGC developer Fred Martin, and then modifying pre-existing Colossus 249
(Apollo 9) source files to incorporate changes. 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, 1968 |
017681,000002: # Copyright: Public domain.
017682,000003: # Filename: GIMBAL_LOCK_AVOIDANCE.agc
017683,000004: # Purpose: Part of the source code for Colossus build 237.
017684,000005: # This is for the Command Module's (CM) Apollo Guidance
017685,000006: # Computer (AGC), we believe for Apollo 8.
017686,000007: # Assembler: yaYUL
017687,000008: # Contact: Onno Hommes <ohommes@alumni.cmu.edu>
017688,000009: # Website: www.ibiblio.org/apollo/index.html
017689,000010: # Page scans: www.ibiblio.org/apollo/ScansForConversion/Colossus237/
017690,000011: # Mod history: 2010-06-01 OH Adapted from corresponding Colossus 249 file.
017691,000012: # 2010-12-04 JL Remove Colossus 249 header comments. Change
017692,000013: # to double-hash page numbers.
017693,000014: # 2011-01-27 JL Minor fixes.
017694,000015:
017695,000016: # # Page 403
017696,000017: 15,2000 BANK 15
017697,000018: 22,2000 SETLOC KALCMON1
017698,000019: 22,2000 BANK
017699,000020:
017700,000021: 22,2736 E6,1661 EBANK= BCDU
017701,000022:
017702,000023: # DETECTING GIMBAL LOCK
017703,000024: 22,2736 22,2736 LOCSKIRT EQUALS NOGIMLOC
017704,000025:
017705,000026: 22,2736 77614 NOGIMLOC SET
017706,000027: 22,2737 01074 CALCMAN3
017707,000028: 22,2740 70740 WCALC LXC,1 DLOAD*
017708,000029: 22,2741 01130 RATEINDX
017709,000030: 22,2742 04772 ARATE,1
017710,000031: 22,2743 45002 SR4 CALL # COMPUTE THE INCREMENTAL ROTATION MATRIX
017711,000032: 22,2744 44530 DELCOMP # DEL CORRESPONDING TO A 1 SEC ROTATION
017712,000033: # ABOUT COF
017713,000034: 22,2745 74343 DLOAD* VXSC
017714,000035: 22,2746 04772 ARATE,1
017715,000036: 22,2747 03343 COF
017716,000037: 22,2750 77721 MXV
017717,000038: 22,2751 05004 QUADROT
017718,000039: 22,2752 17311 STODL BRATE
017719,000040: 22,2753 03365 AM
017720,000041: 22,2754 55605 DMP DDV*
017721,000042: 22,2755 05002 ANGLTIME
017722,000043: 22,2756 04772 ARATE,1
017723,000044: 22,2757 77661 SR
017724,000045: 22,2760 20606 5
017725,000046: 22,2761 27317 STOVL TM
017726,000047: 22,2762 03311 BRATE
017727,000048: 22,2763 77761 VXSC
017728,000049: 22,2764 05026 BIASCALE
017729,000050: 22,2765 03275 STORE BIASTEMP # ATTITUDE ERROR BIAS TO PREVENT OVERSHOOT
017730,000051: # IN SYSTEM
017731,000052: 22,2766 77614 SETGO # STATE SWITCH CALCMAN2 (43D)
017732,000053: 22,2767 01035 CALCMAN2 # 0(OFF) = BYPASS STARTING PROCEDURE
017733,000054: 22,2770 45033 NEWANGL +1 # 1(ON) = START MANEUVER
017734,000055:
017735,000056:
017736,000057: 22,2771 00044 15053 ARATE 2DEC .0022222222 # = .05 DEG/SEC
017737,000058: 22,2773 00221 24255 2DEC .0088888889 # = .2 DEG/SEC
017738,000059: 22,2775 00554 02660 2DEC .0222222222 # = .5 DEG/SEC
017739,000060: 22,2777 05540 26603 2DEC .1777777777 # = 4 DEG/SEC $ 22.5 DEG/SEC
017740,000061: 22,3001 00003 04000 ANGLTIME 2DEC .000190735 # = 100B - 19
017741,000062: # MANEUVER ANGLE TO MANEUVER TIME
017742,000063: # # Page 404
017743,000064: 22,3003 03146 14632 QUADROT 2DEC .1 # ROTATION MATRIX FROM S/C AXES TO CONTROL
017744,000065: 22,3005 00000 00000 2DEC 0 B-28 # AXES (X ROT = -7.25 DEG)
017745,000066: 22,3007 00000 00000 2DEC 0 B-28
017746,000067: 22,3011 00000 00000 2DEC 0 B-28
017747,000068: 22,3013 03131 11275 2DEC .099200 # =(.1)COS7.25
017748,000069: 22,3015 77461 47370 2DEC -.012620 # =-(.1)SIN7.25
017749,000070: 22,3017 00000 00000 2DEC 0 B-28
017750,000071: 22,3021 00316 30407 2DEC .012620 # (.1)SIN7.25
017751,000072: 22,3023 03131 11275 2DEC .099200 # (.1)COS7.25
017752,000073: 22,3025 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