Source Code
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These source-code files were derived from scans of the
Colossus 237 (Apollo 8 Command Module) program listing from the private collection of original
AGC developer Fred Martin. Scanning was by Ron Burkey. Pre-existing Colossus 249
(Apollo 9 CM) source files were used as a template, and changes between Colossus 249
and Colossus 237 were manually transcribed by a team of volunteers. 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, 1968Note that the date is the date of the printout, not the date of the program revision. |
019592,000002: ## Copyright: Public domain.
019593,000003: ## Filename: GROUND_TRACKING_DETERMINATION_PROGRAM_-_P21.agc
019594,000004: ## Purpose: Part of the source code for Colossus build 237.
019595,000005: ## This is for the Command Module's (CM) Apollo Guidance
019596,000006: ## Computer (AGC), for Apollo 8.
019597,000007: ## Assembler: yaYUL
019598,000008: ## Contact: Jim Lawton <jim DOT lawton AT gmail DOT com>
019599,000009: ## Website: www.ibiblio.org/apollo/index.html
019600,000010: ## Page Scans: www.ibiblio.org/apollo/ScansForConversion/Colossus237/
019601,000011: ## Mod history: 2011-02-02 JL Adapted from corresponding Colossus 249 file.
019602,000012: ## 2016-12-31 RSB Proofed comment text using octopus/ProoferComments,
019603,000013: ## and corrected errors found.
019604,000014: ## 2017-01-14 RSB Corrected comment-errors located in diff'ing
019605,000015: ## vs Colossus 249
019606,000016:
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Page 447 |
019608,000018: # GROUND TRACKING DETERMINATION PROGRAM P21
019609,000019: # PROGRAM DESCRIPTION
019610,000020: # MOD NO - 1
019611,000021: # MOD BY - N.M.NEVILLE
019612,000022: # FUNCTIONAL DECRIPTION-
019613,000023:
019614,000024: # TO PROVIDE THE ASTRONAUT DETAILS OF THE LM OR CSM GROUND TRACK WITHOUT
019615,000025: # THE NEED FOR GROUND COMMUNICATION (REQUESTED BY DSKY).
019616,000026: # CALLING SEQUENCE-
019617,000027:
019618,000028: # ASTRONAUT REQUEST THROUGH DSKY V37E21E
019619,000029: # SUBROUTINES CALLED-
019620,000030:
019621,000031: # GOPERF4
019622,000032: # GOFLASH
019623,000033: # THISPREC
019624,000034: # OTHPREC
019625,000035: # LAT-LONG
019626,000036: # NORMAL EXIT MODES-
019627,000037:
019628,000038: # ASTRONAUT REQUEST TROUGH DSKY TO TERMINATE PROGRAM V34E
019629,000039: # ALARM OR ABORT EXIT MODES-
019630,000040:
019631,000041: # NONE
019632,000042: # OUTPUT-
019633,000043:
019634,000044: # OCTAL DISPLAY OF OPTION CODE AND VEHICLE WHOSE GROUND TRACK IS TO BE
019635,000045: # COMPUTED
019636,000046: # OPTION CODE 00002
019637,000047: # THIS 00001
019638,000048: # OTHER 00002
019639,000049: # DECIMAL DISPLAY OF TIME TO BE INTEGRATED TO HOURS , MINUTES , SECONDS
019640,000050: # DECIMAL DISPLAY OF LAT,LONG,ALT
019641,000051: # ERASABLE INITIALIZATION REQUIRED
019642,000052:
019643,000053: # AX0 2DEC 4.652459653 E-5 RADIANS %68-69 CONSTANTS"
019644,000054:
019645,000055: # -AY0 2DEC 2.147535898 E-5 RADIANS
019646,000056:
019647,000057: # AZ0 2DEC .7753206164 REVOLUTIONS
019648,000058: # FOR LUNAR ORBITS 504LM VECTOR IS NEEDED
019649,000059:
019650,000060: # 504LM 2DEC -2.700340600 E-5 RADIANS
019651,000061:
019652,000062: # 504LM _2 2DEC -7.514128400 E-4 RADIANS
019653,000063:
019654,000064: # 504LM _4 2DEC _2.553198641 E-4 RADIANS
019655,000065:
019656,000066: # NONE
019657,000067: # DEBRIS
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Page 448 |
019659,000069:
019660,000070: # CENTRALS-A,Q,L
019661,000071: # OTHER-THOSE USED BY THE ABOVE LISTED SUBROUTINES
019662,000072: # SEE LEMPREC,LAT-LONG
019663,000073: 33,3773 30,2000 SBANK= LOWSUPER # FOR LOW 2CADR'S.
019664,000074:
019665,000075: 33,3773 BANK 33
019666,000076: 37,2000 SETLOC P20S
019667,000077: 37,2000 BANK
019668,000078:
019669,000079: 37,2001 E4,1715 EBANK= P21TIME
019670,000080: 37,2001 COUNT 24/P21
019671,000081:
019672,000082: 37,2001 34712 PROG21 CAF ONE
019673,000083: 37,2002 55132 TS OPTION2 # ASSUMED VEHICLE IS LM , R2 = 00001
019674,000084: 37,2003 34711 CAF BIT2 # OPTION 2
019675,000085: 37,2004 04555 TC BANKCALL
019676,000086: 37,2005 20761 CADR GOPERF4
019677,000087: 37,2006 04106 TC GOTOPOOH # TERMINATE
019678,000088: 37,2007 02011 TC +2 # PROCEED VALUE OF ASSUMED VEHICLE OK
019679,000089: 37,2010 02003 TC -5 # R2 LOADED THROUGH DSKY
019680,000090: 37,2011 32102 P21PROG1 CAF V6N34 # LOAD DESIRED TIME OF LAT-LONG.
019681,000091: 37,2012 04555 TC BANKCALL
019682,000092: 37,2013 20624 CADR GOFLASH
019683,000093: 37,2014 04106 TC GOTOPOOH # TERM
019684,000094: 37,2015 02017 TC +2 # PROCEED VALUES OK
019685,000095: 37,2016 02011 TC -5 # TIME LOADED THROUGH DSKY
019686,000096: 37,2017 06006 TC INTPRET
019687,000097: 37,2020 77745 DLOAD
019688,000098: 37,2021 01046 DSPTEM1
019689,000099: 37,2022 02316 STORE P21TIME
019690,000100: 37,2023 45335 SLOAD DSU
019691,000101: 37,2024 01133 OPTION2
019692,000102: 37,2025 36100 P21ONENN
019693,000103: 37,2026 71230 BHIZ DLOAD
019694,000104: 37,2027 76042 P21PROG2 # VEHICLE TO BE INTEGRATED IS LEM
019695,000105: 37,2030 02316 P21TIME # VEHICLE TO BE INTEGRATED IS CSM
019696,000106: 37,2031 34041 STCALL TDEC1 # INTEGRATE TO TIME SPECIFIED IN TDEC
019697,000107: 37,2032 27036 OTHPREC # ADJUST UNITS FOR LAT-LONG ROUTINE
019698,000108: 37,2033 46135 P21PROGA SLOAD BHIZ
019699,000109: 37,2034 00050 X2
019700,000110: 37,2035 76050 P21PROG3
019701,000111: 37,2036 43175 VLOAD SETGO
019702,000112: 37,2037 00001 RATT
019703,000113: 37,2040 01423 LUNAFLAG
019704,000114: 37,2041 76053 P21PROG4
019705,000115: 37,2042 77745 P21PROG2 DLOAD
019706,000116: 37,2043 02316 P21TIME
019707,000117: 37,2044 34041 STCALL TDEC1
019708,000118: 37,2045 27022 THISPREC
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019710,000120: 37,2046 77650 GOTO
019711,000121: 37,2047 76033 P21PROGA
019712,000122: 37,2050 43175 P21PROG3 VLOAD CLEAR
019713,000123: 37,2051 00001 RATT
019714,000124: 37,2052 01663 LUNAFLAG
019715,000125: 37,2053 16152 P21PROG4 STODL ALPHAV
019716,000126: 37,2054 00015 TAT
019717,000127: 37,2055 45014 CLEAR CALL
019718,000128: 37,2056 00662 ERADFLAG
019719,000129: 37,2057 26322 LAT-LONG
019720,000130: 37,2060 77776 EXIT
019721,000131: 37,2061 32101 CAF V06N43 # DISPLAY LAT,LONG,ALT
019722,000132: 37,2062 04555 TC BANKCALL # LAT,LONG = 1/2 REVS B0
019723,000133: 37,2063 20624 CADR GOFLASH # ALT = KM B14
019724,000134: 37,2064 04106 TC GOTOPOOH # TERM
019725,000135: 37,2065 04106 TC GOTOPOOH
019726,000136: 37,2066 06006 TC INTPRET # V32E RECYCLE
019727,000137: 37,2067 43345 DLOAD DAD
019728,000138: 37,2070 02316 P21TIME
019729,000139: 37,2071 36076 600SEC # 600 SECONDS OR 10 MIN
019730,000140: 37,2072 01046 STORE DSPTEM1
019731,000141: 37,2073 77634 RTB
019732,000142: 37,2074 76011 P21PROG1
019733,000143:
019734,000144: 37,2075 00003 25140 600SEC 2DEC 60000 B-28 # 10 MIN
019735,000145: 37,2077 00001 P21ONENN OCT 00001 # NEEDED TO DETERMINE VEHICLE
019736,000146: 37,2100 00000 OCT 00000 # TO BE INTEGRATED
019737,000147: 37,2101 01453 V06N43 VN 00643
019738,000148: 37,2102 01442 V6N34 VN 00634
End of include-file GROUND_TRACKING_DETERMINATION_PROGRAM_-_P21.agc. Parent file is MAIN.agc