Source Code
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These source-code files were from the printout at the MIT Museum, with many thanks
to Deborah Douglas, the Museum's Curator of Science and Technology, for releasing
it to us. The printout was digitally photographed by Paul Fjeld. A team of
volunteers transcribed the source code manually from these images or, where
appropriate, modified already-transcribed but similar source Colossus 249 (Apollo 9)
source code to agree with the images from the printout. Note that the page images
presented online are of reduced quality, and that higher-quality 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 055 OF AGC PROGRAM COMANCHE BY NASA 2021113-051 10:28 APR. 1,1969Note that the date is the date of the printout, not the date of the program revision. |
018059,000002: ## Copyright: Public domain.
018060,000003: ## Filename: GIMBAL_LOCK_AVOIDANCE.agc
018061,000004: ## Purpose: Part of the source code for Comanche, build 055.
018062,000005: ## It is part of the source code for the Command Module's (CM)
018063,000006: ## Apollo Guidance Computer (AGC), Apollo 11.
018064,000007: ## Assembler: yaYUL
018065,000008: ## Reference: pp. 412-413
018066,000009: ## Contact: Onno Hommes <ohommes@cmu.edu>.
018067,000010: ## Website: www.ibiblio.org/apollo.
018068,000011: ## Mod history: 05/07/09 OH Transcription Batch 1 Assignment
018069,000012: ## 2016-12-10 RSB Proofed comments with octopus/ProoferComments
018070,000013: ## and fixed the errors found.
018071,000014: ##
018072,000015: ## The contents of the "Comanche055" files, in general, are transcribed
018073,000016: ## from scanned documents.
018074,000017: ##
018075,000018: ## Assemble revision 055 of AGC program Comanche by NASA
018076,000019: ## 2021113-051. April 1, 1969.
018077,000020: ##
018078,000021: ## This AGC program shall also be referred to as Colossus 2A
018079,000022: ##
018080,000023: ## Prepared by
018081,000024: ## Massachusetts Institute of Technology
018082,000025: ## 75 Cambridge Parkway
018083,000026: ## Cambridge, Massachusetts
018084,000027: ##
018085,000028: ## under NASA contract NAS 9-4065.
018086,000029: ##
018087,000030: ## Refer directly to the online document mentioned above for further information.
018088,000031: ## Please report any errors to info@sandroid.org.
018089,000032:
018090,000033:
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Page 412 |
018092,000035: 15,2000 BANK 15
018093,000036: 22,2000 SETLOC KALCMON1
018094,000037: 22,2000 BANK
018095,000038:
018096,000039: 22,2737 E6,1661 EBANK= BCDU
018097,000040:
018098,000041: # DETECTING GIMBAL LOCK
018099,000042: 22,2737 22,2737 LOCSKIRT EQUALS WCALC
018100,000043: 22,2737 70740 WCALC LXC,1 DLOAD*
018101,000044: 22,2740 01130 RATEINDX
018102,000045: 22,2741 04771 ARATE,1
018103,000046: 22,2742 45002 SR4 CALL # COMPUTE THE INCREMENTAL ROTATION MATRIX
018104,000047: 22,2743 44530 DELCOMP # DEL CORRESPONDING TO A 1 SEC ROTATION
018105,000048: # ABOUT COF
018106,000049: 22,2744 74343 DLOAD* VXSC
018107,000050: 22,2745 04771 ARATE,1
018108,000051: 22,2746 03343 COF
018109,000052: 22,2747 77721 MXV
018110,000053: 22,2750 05003 QUADROT
018111,000054: 22,2751 17311 STODL BRATE
018112,000055: 22,2752 03365 AM
018113,000056: 22,2753 55605 DMP DDV*
018114,000057: 22,2754 05001 ANGLTIME
018115,000058: 22,2755 04771 ARATE,1
018116,000059: 22,2756 77661 SR
018117,000060: 22,2757 20606 5
018118,000061: 22,2760 27317 STOVL TM
018119,000062: 22,2761 03311 BRATE
018120,000063: 22,2762 77761 VXSC
018121,000064: 22,2763 05025 BIASCALE
018122,000065: 22,2764 03275 STORE BIASTEMP # ATTITUDE ERROR BIAS TO PREVENT OVERSHOOT
018123,000066: # IN SYSTEM
018124,000067: 22,2765 77614 SETGO # STATE SWITCH CALCMAN2 (43D)
018125,000068: 22,2766 01035 CALCMAN2 # 0(OFF) = BYPASS STARTING PROCEDURE
018126,000069: 22,2767 45032 NEWANGL +1 # 1(ON) = START MANEUVER
018127,000070:
018128,000071:
018129,000072: 22,2770 00044 15053 ARATE 2DEC .0022222222 # = .05 DEG/SEC
018130,000073:
018131,000074: 22,2772 00221 24255 2DEC .0088888889 # = .2 DEG/SEC
018132,000075:
018133,000076: 22,2774 00554 02660 2DEC .0222222222 # = .5 DEG/SEC
018134,000077:
018135,000078: 22,2776 02660 13301 2DEC .0888888889 # = 2 DEG/SEC $22.5 DEG/SEC
018136,000079:
018137,000080: 22,3000 00003 04000 ANGLTIME 2DEC .000190735 # = 100B - 19
018138,000081:
018139,000082: # MANEUVER ANGLE TO MANEUVER TIME
018140,000083: 22,3002 03146 14632 QUADROT 2DEC .1 # ROTATION MATRIX FROM S/C AXES TO CONTROL
018141,000084:
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Page 413 |
018143,000086: 22,3004 00000 00000 2DEC 0 B-28 # AXES (X ROT = -7.25 DEG)
018144,000087:
018145,000088: 22,3006 00000 00000 2DEC 0 B-28
018146,000089:
018147,000090: 22,3010 00000 00000 2DEC 0 B-28
018148,000091:
018149,000092: 22,3012 03131 11275 2DEC .099200 # =(.1)COS7.25
018150,000093:
018151,000094: 22,3014 77461 47370 2DEC -.012620 # =-(.1)SIN7.25
018152,000095:
018153,000096: 22,3016 00000 00000 2DEC 0 B-28
018154,000097:
018155,000098: 22,3020 00316 30407 2DEC .012620 # (.1)SIN7.25
018156,000099:
018157,000100: 22,3022 03131 11275 2DEC .099200 # (.1)COS7.25
018158,000101:
018159,000102: 22,3024 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