Notations on the program listing read, in part:
GAP: ASSEMBLE REVISION 116 OF AGC PROGRAM LUMINARY BY NASA 2021112-071 19:09 AUG. 11,1969Note that the date is the date of the printout, not the date of the program revision.
Source Code
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These source-code files derive from a printout of Luminary 116 (the Apollo 12
Lunar Module guidance computer program), from the personal library of
original AGC developer Don Eyles, digitally photographed at archive.org,
financially sponsored by Ron Burkey, and transcribed to source code by a
team of volunteers. This colorized, syntax-highlighted form was created
by assembling that transcribed source code. Note that the full page images
are available on the
Virtual AGC project page at archive.org, while reduced-size images
are presented at the VirtualAGC project website. Report or fix any
transcription errors at
the Virtual AGC project code repository. Notations on the program listing read, in part: GAP: ASSEMBLE REVISION 116 OF AGC PROGRAM LUMINARY BY NASA 2021112-071 19:09 AUG. 11,1969Note that the date is the date of the printout, not the date of the program revision. |
027898,000002: ## Copyright: Public domain.
027899,000003: ## Filename: GROUND_TRACKING_DETERMINATION_PROGRAM_-_P21.agc
027900,000004: ## Purpose: A section of Luminary revision 116.
027901,000005: ## It is part of the source code for the Lunar Module's (LM)
027902,000006: ## Apollo Guidance Computer (AGC) for Apollo 12.
027903,000007: ## This file is intended to be a faithful transcription, except
027904,000008: ## that the code format has been changed to conform to the
027905,000009: ## requirements of the yaYUL assembler rather than the
027906,000010: ## original YUL assembler.
027907,000011: ## Reference: pp. 654-657
027908,000012: ## Assembler: yaYUL
027909,000013: ## Contact: Ron Burkey <info@sandroid.org>.
027910,000014: ## Website: www.ibiblio.org/apollo/index.html
027911,000015: ## Mod history: 2017-01-22 MAS Created from Luminary 99.
027912,000016: ## 2017-02-12 NV Updated for Luminary 116.
027913,000017: ## 2017-03-01 RSB Proofed comment text by diff vs Luminary 131
027914,000018: ## but no errors found.
027915,000019:
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Page 654 |
027917,000021: # GROUND TRACKING DETERMINATION PROGRAM P21
027918,000022: # PROGRAM DESCRIPTION
027919,000023: # MOD NO - 1
027920,000024: # MOD BY - N. M. NEVILLE
027921,000025:
027922,000026: # FUNCTIONAL DECRIPTION -
027923,000027: # TO PROVIDE THE ASTRONAUT DETAILS OF THE LM OR CSM GROUND TRACK WITHOUT
027924,000028: # THE NEED FOR GROUND COMMUNICATION (REQUESTED BY DSKY).
027925,000029:
027926,000030: # CALLING SEQUENCE -
027927,000031: # ASTRONAUT REQUEST THROUGH DSKY V37E21E
027928,000032:
027929,000033: # SUBROUTINES CALLED -
027930,000034: # GOPERF4
027931,000035: # GOFLASH
027932,000036: # THISPREC
027933,000037: # OTHPREC
027934,000038: # LAT-LONG
027935,000039:
027936,000040: # NORMAL EXIT MODES -
027937,000041: # ASTRONAUT REQUEST TROUGH DSKY TO TERMINATE PROGRAM V34E
027938,000042:
027939,000043: # ALARM OR ABORT EXIT MODES -
027940,000044: # NONE
027941,000045:
027942,000046: # OUTPUT -
027943,000047: # OCTAL DISPLAY OF OPTION CODE AND VEHICLE WHOSE GROUND TRACK IS TO BE
027944,000048: # COMPUTED
027945,000049: # OPTION CODE 00002
027946,000050: # THIS 00001
027947,000051: # OTHER 00002
027948,000052: # DECIMAL DISPLAY OF TIME TO BE INTEGRATED TO HOURS, MINUTES, SECONDS
027949,000053: # DECIMAL DISPLAY OF LAT,LONG,ALT
027950,000054:
027951,000055: # ERASABLE INITIALIZATION REQUIRED
027952,000056: # AX0 2DEC 4.652459653 E-5 RADIANS %68-69 CONSTANTS"
027953,000057: # -AY0 2DEC 2.147535898 E-5 RADIANS
027954,000058: # AZ0 2DEC .7753206164 REVOLUTIONS
027955,000059: # FOR LUNAR ORBITS 504LM VECTOR IS NEEDED
027956,000060: # 504LM 2DEC -2.700340600 E-5 RADIANS
027957,000061: # 504LM _2 2DEC -7.514128400 E-4 RADIANS
027958,000062: # 504LM _4 2DEC _2.553198641 E-4 RADIANS
027959,000063:
027960,000064: # NONE
027961,000065:
027962,000066: # DEBRIS
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Page 655 |
027964,000068: # CENTRALS - A,Q,L
027965,000069: # OTHER - THOSE USED BY THE ABOVE LISTED SUBROUTINES
027966,000070: # SEE LEMPREC, LAT-LONG
027967,000071:
027968,000072: 35,2455 30,2000 SBANK= LOWSUPER # FOR LOW 2CADR'S.
027969,000073:
027970,000074: 33,2200 BANK 33
027971,000075: 24,2000 SETLOC P20S
027972,000076: 24,2000 BANK
027973,000077:
027974,000078: 24,3505 E7,1762 EBANK= P21TIME
027975,000079: 24,3505 COUNT* $$/P21
027976,000080: 24,3505 34753 PROG21 CAF ONE
027977,000081: 24,3506 55144 TS OPTION2 # ASSUMED VEHICLE IS LM, R2 = 00001
027978,000082: 24,3507 34752 CAF BIT2 # OPTION 2
027979,000083: 24,3510 04616 TC BANKCALL
027980,000084: 24,3511 20634 CADR GOPERF4
027981,000085: 24,3512 06001 TC GOTOPOOH # TERMINATE
027982,000086: 24,3513 03515 TC +2 # PROCEED VALUE OF ASSUMED VEHICLE OK
027983,000087: 24,3514 03507 TC -5 # R2 LOADED THROUGH DSKY
027984,000088: 24,3515 34755 CAF ZERO # INITIAL TIME = PRESENT TIME
027985,000089: 24,3516 55044 TS DSPTEM1
027986,000090: 24,3517 55045 TS DSPTEM1 +1
027987,000091: 24,3520 33674 P21PROG1 CAF V6N34 # LOAD DESIRED TIME OF LAT-LONG.
027988,000092: 24,3521 04616 TC BANKCALL
027989,000093: 24,3522 20477 CADR GOFLASH
027990,000094: 24,3523 06001 TC GOTOPOOH # TERM
027991,000095: 24,3524 03526 TC +2 # PROCEED VALUES OK
027992,000096: 24,3525 03520 TC -5 # TIME LOADED THROUGH DSKY
027993,000097: 24,3526 06042 TC INTPRET
027994,000098: 24,3527 53145 DLOAD BZE
027995,000099: 24,3530 01045 DSPTEM1
027996,000100: 24,3531 51666 P21PRTM
027997,000101: 24,3532 34041 P21PROG2 STCALL TDEC1 # INTEG TO TIME SPECIFIED IN TDEC1
027998,000102: 24,3533 27412 INTSTALL
027999,000103: 24,3534 43014 BON CLEAR
028000,000104: 24,3535 00304 P21FLAG
028001,000105: 24,3536 51554 P21CONT # ON --- RECYCLE USING BASE VECTOR
028002,000106: 24,3537 01674 VINTFLAG # OFF -- 1ST PASS CALL BASE VECTOR
028003,000107: 24,3540 70535 SLOAD SR1
028004,000108: 24,3541 01145 OPTION2
028005,000109: 24,3542 43030 BHIZ SET
028006,000110: 24,3543 51545 +2 # ZERO -- THIS VEHICLE (LM)
028007,000111: 24,3544 01474 VINTFLAG # ONE -- OTHER VEHICLE (CM)
028008,000112: 24,3545 43014 CLEAR CLEAR
028009,000113: 24,3546 01676 DIM0FLAG
028010,000114: 24,3547 01673 INTYPFLG # PRECISION
028011,000115: 24,3550 77624 CALL
028012,000116: 24,3551 27135 INTEGRV # CALCULATE
028013,000117: 24,3552 77650 GOTO # -AND
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Page 656 |
028015,000119: 24,3553 51575 P21VSAVE # -SAVE BASE VECTOR
028016,000120: 24,3554 77775 P21CONT VLOAD
028017,000121: 24,3555 03676 P21BASER # RECYCLE -- INTEG FROM BASE VECTOR
028018,000122: 24,3556 25535 STOVL RCV # --POS
028019,000123: 24,3557 03704 P21BASEV
028020,000124: 24,3560 15543 STODL VCV # --VEL
028021,000125: 24,3561 03763 P21TIME
028022,000126: 24,3562 01517 STORE TET # --TIME
028023,000127: 24,3563 43014 CLEAR CLEAR
028024,000128: 24,3564 01676 DIM0FLAG
028025,000129: 24,3565 00263 MOONFLAG
028026,000130: 24,3566 53135 SLOAD BZE
028027,000131: 24,3567 01163 P21ORIG
028028,000132: 24,3570 51573 +3 # ZERO = EARTH
028029,000133: 24,3571 77614 SET # ---2 = MOON
028030,000134: 24,3572 00063 MOONFLAG
028031,000135: 24,3573 77624 +3 CALL
028032,000136: 24,3574 27110 INTEGRVS
028033,000137: 24,3575 77745 P21VSAVE DLOAD # SAVE CURRENT BASEVECTOR
028034,000138: 24,3576 00015 TAT
028035,000139: 24,3577 27763 STOVL P21TIME # --TIME
028036,000140: 24,3600 00017 RATT1
028037,000141: 24,3601 27676 STOVL P21BASER # --POS B-29 OR B-27
028038,000142: 24,3602 00025 VATT1
028039,000143: 24,3603 03704 STORE P21BASEV # --VEL B-07 OR B-05
028040,000144: 24,3604 53646 ABVAL SL*
028041,000145: 24,3605 57576 0,2
028042,000146: 24,3606 27712 STOVL P21VEL # VEL/ FOR N91 DISP
028043,000147: 24,3607 00001 RATT
028044,000148: 24,3610 50256 UNIT DOT
028045,000149: 24,3611 00007 VATT # U(R).V
028046,000150: 24,3612 67471 DDV ASIN # U(R).U(V)
028047,000151: 24,3613 03712 P21VEL
028048,000152: 24,3614 03714 STORE P21GAM # SIN-1 U(R).U(V) , -90 TO &90
028049,000153: 24,3615 67334 SXA,2 SLOAD
028050,000154: 24,3616 01162 P21ORIG # 0 = EARTH
028051,000155: 24,3617 01145 OPTION2
028052,000156: 24,3620 46142 SR1 BHIZ
028053,000157: 24,3621 51624 +3
028054,000158: 24,3622 77650 GOTO
028055,000159: 24,3623 51627 +4
028056,000160: 24,3624 77614 +3 BON
028057,000161: 24,3625 04307 SURFFLAG
028058,000162: 24,3626 51631 P21DSP
028059,000163: 24,3627 77614 +4 SET
028060,000164: 24,3630 00064 P21FLAG
028061,000165: 24,3631 67214 P21DSP CLEAR SLOAD # GENERATE DISPLAY DATA
028062,000166: 24,3632 01663 LUNAFLAG
028063,000167: 24,3633 00050 X2
028064,000168: 24,3634 43054 BZE SET
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028066,000170: 24,3635 51637 +2 # 0 = EARTH
028067,000171: 24,3636 01463 LUNAFLAG
028068,000172: 24,3637 77775 VLOAD
028069,000173: 24,3640 00001 RATT
028070,000174: 24,3641 16032 STODL ALPHAV
028071,000175: 24,3642 00015 TAT
028072,000176: 24,3643 45014 CLEAR CALL
028073,000177: 24,3644 00662 ERADFLAG
028074,000178: 24,3645 26351 LAT-LONG
028075,000179: 24,3646 77605 DMP # MPAC = ALT, METERS B-29
028076,000180: 24,3647 11676 K.01
028077,000181: 24,3650 03716 STORE P21ALT # ALT/100 FOR N91 DISP
028078,000182: 24,3651 77776 EXIT
028079,000183: 24,3652 33673 CAF V06N43 # DISPLAY LAT, LONG, ALT
028080,000184: 24,3653 04616 TC BANKCALL # LAT, LONG = 1/2 REVS B0
028081,000185: 24,3654 20477 CADR GOFLASH # ALT = KM B14
028082,000186: 24,3655 06001 TC GOTOPOOH # TERM
028083,000187: 24,3656 06001 TC GOTOPOOH
028084,000188: 24,3657 06042 TC INTPRET # V32E RECYCLE
028085,000189: 24,3660 43345 DLOAD DAD
028086,000190: 24,3661 03763 P21TIME
028087,000191: 24,3662 11672 600SEC # 600 SECONDS OR 10 MIN
028088,000192: 24,3663 01045 STORE DSPTEM1
028089,000193: 24,3664 77634 RTB
028090,000194: 24,3665 51520 P21PROG1
028091,000195: 24,3666 52034 P21PRTM RTB GOTO
028092,000196: 24,3667 21574 LOADTIME
028093,000197: 24,3670 51532 P21PROG2
028094,000198: 24,3671 00003 25140 600SEC 2DEC 60000 B-28 # 10 MIN
028095,000199:
028096,000200: 24,3673 01453 V06N43 VN 00643
028097,000201: 24,3674 01442 V6N34 VN 00634
028098,000202: 24,3675 00243 32703 K.01 2DEC .01
028099,000203:
End of include-file GROUND_TRACKING_DETERMINATION_PROGRAM_-_P21.agc. Parent file is MAIN.agc