Source Code
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. |
019590,000002: ## Copyright: Public domain.
019591,000003: ## Filename: GROUND_TRACKING_DETERMINATION_PROGRAM_-_P21.agc
019592,000004: ## Purpose: Part of the source code for Colossus build 237.
019593,000005: ## This is for the Command Module's (CM) Apollo Guidance
019594,000006: ## Computer (AGC), for Apollo 8.
019595,000007: ## Assembler: yaYUL
019596,000008: ## Contact: Jim Lawton <jim DOT lawton AT gmail DOT com>
019597,000009: ## Website: www.ibiblio.org/apollo/index.html
019598,000010: ## Page Scans: www.ibiblio.org/apollo/ScansForConversion/Colossus237/
019599,000011: ## Mod history: 2011-02-02 JL Adapted from corresponding Colossus 249 file.
019600,000012: ## 2016-12-31 RSB Proofed comment text using octopus/ProoferComments,
019601,000013: ## and corrected errors found.
019602,000014: ## 2017-01-14 RSB Corrected comment-errors located in diff'ing
019603,000015: ## vs Colossus 249
019604,000016:
Page 447 |
019606,000018: # GROUND TRACKING DETERMINATION PROGRAM P21
019607,000019: # PROGRAM DESCRIPTION
019608,000020: # MOD NO - 1
019609,000021: # MOD BY - N.M.NEVILLE
019610,000022: # FUNCTIONAL DECRIPTION-
019611,000023:
019612,000024: # TO PROVIDE THE ASTRONAUT DETAILS OF THE LM OR CSM GROUND TRACK WITHOUT
019613,000025: # THE NEED FOR GROUND COMMUNICATION (REQUESTED BY DSKY).
019614,000026: # CALLING SEQUENCE-
019615,000027:
019616,000028: # ASTRONAUT REQUEST THROUGH DSKY V37E21E
019617,000029: # SUBROUTINES CALLED-
019618,000030:
019619,000031: # GOPERF4
019620,000032: # GOFLASH
019621,000033: # THISPREC
019622,000034: # OTHPREC
019623,000035: # LAT-LONG
019624,000036: # NORMAL EXIT MODES-
019625,000037:
019626,000038: # ASTRONAUT REQUEST TROUGH DSKY TO TERMINATE PROGRAM V34E
019627,000039: # ALARM OR ABORT EXIT MODES-
019628,000040:
019629,000041: # NONE
019630,000042: # OUTPUT-
019631,000043:
019632,000044: # OCTAL DISPLAY OF OPTION CODE AND VEHICLE WHOSE GROUND TRACK IS TO BE
019633,000045: # COMPUTED
019634,000046: # OPTION CODE 00002
019635,000047: # THIS 00001
019636,000048: # OTHER 00002
019637,000049: # DECIMAL DISPLAY OF TIME TO BE INTEGRATED TO HOURS , MINUTES , SECONDS
019638,000050: # DECIMAL DISPLAY OF LAT,LONG,ALT
019639,000051: # ERASABLE INITIALIZATION REQUIRED
019640,000052:
019641,000053: # AX0 2DEC 4.652459653 E-5 RADIANS %68-69 CONSTANTS"
019642,000054:
019643,000055: # -AY0 2DEC 2.147535898 E-5 RADIANS
019644,000056:
019645,000057: # AZ0 2DEC .7753206164 REVOLUTIONS
019646,000058: # FOR LUNAR ORBITS 504LM VECTOR IS NEEDED
019647,000059:
019648,000060: # 504LM 2DEC -2.700340600 E-5 RADIANS
019649,000061:
019650,000062: # 504LM _2 2DEC -7.514128400 E-4 RADIANS
019651,000063:
019652,000064: # 504LM _4 2DEC _2.553198641 E-4 RADIANS
019653,000065:
019654,000066: # NONE
019655,000067: # DEBRIS
Page 448 |
019657,000069:
019658,000070: # CENTRALS-A,Q,L
019659,000071: # OTHER-THOSE USED BY THE ABOVE LISTED SUBROUTINES
019660,000072: # SEE LEMPREC,LAT-LONG
019661,000073: 33,3773 30,2000 SBANK= LOWSUPER # FOR LOW 2CADR'S.
019662,000074:
019663,000075: 33,3773 BANK 33
019664,000076: 37,2000 SETLOC P20S
019665,000077: 37,2000 BANK
019666,000078:
019667,000079: 37,2001 E4,1715 EBANK= P21TIME
019668,000080: 37,2001 COUNT 24/P21
019669,000081:
019670,000082: 37,2001 34712 PROG21 CAF ONE
019671,000083: 37,2002 55132 TS OPTION2 # ASSUMED VEHICLE IS LM , R2 = 00001
019672,000084: 37,2003 34711 CAF BIT2 # OPTION 2
019673,000085: 37,2004 04555 TC BANKCALL
019674,000086: 37,2005 20761 CADR GOPERF4
019675,000087: 37,2006 04106 TC GOTOPOOH # TERMINATE
019676,000088: 37,2007 02011 TC +2 # PROCEED VALUE OF ASSUMED VEHICLE OK
019677,000089: 37,2010 02003 TC -5 # R2 LOADED THROUGH DSKY
019678,000090: 37,2011 32102 P21PROG1 CAF V6N34 # LOAD DESIRED TIME OF LAT-LONG.
019679,000091: 37,2012 04555 TC BANKCALL
019680,000092: 37,2013 20624 CADR GOFLASH
019681,000093: 37,2014 04106 TC GOTOPOOH # TERM
019682,000094: 37,2015 02017 TC +2 # PROCEED VALUES OK
019683,000095: 37,2016 02011 TC -5 # TIME LOADED THROUGH DSKY
019684,000096: 37,2017 06006 TC INTPRET
019685,000097: 37,2020 77745 DLOAD
019686,000098: 37,2021 01046 DSPTEM1
019687,000099: 37,2022 02316 STORE P21TIME
019688,000100: 37,2023 45335 SLOAD DSU
019689,000101: 37,2024 01133 OPTION2
019690,000102: 37,2025 36100 P21ONENN
019691,000103: 37,2026 71230 BHIZ DLOAD
019692,000104: 37,2027 76042 P21PROG2 # VEHICLE TO BE INTEGRATED IS LEM
019693,000105: 37,2030 02316 P21TIME # VEHICLE TO BE INTEGRATED IS CSM
019694,000106: 37,2031 34041 STCALL TDEC1 # INTEGRATE TO TIME SPECIFIED IN TDEC
019695,000107: 37,2032 27036 OTHPREC # ADJUST UNITS FOR LAT-LONG ROUTINE
019696,000108: 37,2033 46135 P21PROGA SLOAD BHIZ
019697,000109: 37,2034 00050 X2
019698,000110: 37,2035 76050 P21PROG3
019699,000111: 37,2036 43175 VLOAD SETGO
019700,000112: 37,2037 00001 RATT
019701,000113: 37,2040 01423 LUNAFLAG
019702,000114: 37,2041 76053 P21PROG4
019703,000115: 37,2042 77745 P21PROG2 DLOAD
019704,000116: 37,2043 02316 P21TIME
019705,000117: 37,2044 34041 STCALL TDEC1
019706,000118: 37,2045 27022 THISPREC
Page 449 |
019708,000120: 37,2046 77650 GOTO
019709,000121: 37,2047 76033 P21PROGA
019710,000122: 37,2050 43175 P21PROG3 VLOAD CLEAR
019711,000123: 37,2051 00001 RATT
019712,000124: 37,2052 01663 LUNAFLAG
019713,000125: 37,2053 16152 P21PROG4 STODL ALPHAV
019714,000126: 37,2054 00015 TAT
019715,000127: 37,2055 45014 CLEAR CALL
019716,000128: 37,2056 00662 ERADFLAG
019717,000129: 37,2057 26322 LAT-LONG
019718,000130: 37,2060 77776 EXIT
019719,000131: 37,2061 32101 CAF V06N43 # DISPLAY LAT,LONG,ALT
019720,000132: 37,2062 04555 TC BANKCALL # LAT,LONG = 1/2 REVS B0
019721,000133: 37,2063 20624 CADR GOFLASH # ALT = KM B14
019722,000134: 37,2064 04106 TC GOTOPOOH # TERM
019723,000135: 37,2065 04106 TC GOTOPOOH
019724,000136: 37,2066 06006 TC INTPRET # V32E RECYCLE
019725,000137: 37,2067 43345 DLOAD DAD
019726,000138: 37,2070 02316 P21TIME
019727,000139: 37,2071 36076 600SEC # 600 SECONDS OR 10 MIN
019728,000140: 37,2072 01046 STORE DSPTEM1
019729,000141: 37,2073 77634 RTB
019730,000142: 37,2074 76011 P21PROG1
019731,000143:
019732,000144: 37,2075 00003 25140 600SEC 2DEC 60000 B-28 # 10 MIN
019733,000145: 37,2077 00001 P21ONENN OCT 00001 # NEEDED TO DETERMINE VEHICLE
019734,000146: 37,2100 00000 OCT 00000 # TO BE INTEGRATED
019735,000147: 37,2101 01453 V06N43 VN 00643
019736,000148: 37,2102 01442 V6N34 VN 00634
End of include-file GROUND_TRACKING_DETERMINATION_PROGRAM_-_P21.agc. Parent file is MAIN.agc