Source Code
|
|
This is an attempt to recreate Luminary 99 Rev 2, otherwise known as LUM99R2, from Luminary 99 Rev 1 and ephemeris data from Luminary 116. The differences are confined to the last 10-12 lines of the CONTROLLED CONSTANTS. Luminary 99 Rev 1 source-code was transcribed from a printout in the MIT Museum, while Luminary 116 source code was transcribed from a printout belonging to Don Eyles. AGC developer James Kernan, the "rope mother" for the Apollo 11 Lunar Module's AGC, explains as follows: "At the last minute, Dan Lickly, our chief engineer, appeared with ephemerides updates and it took two tries to get it right. The result was that we created Lum99 Revision 1 and Lum99 Revision 2." It is suspected that the former is what's in the MIT Museum, and the latter is what we are trying to recreate here. As for which revision actually flew in Apollo 11, all of the other available surviving evidence points to Rev 1 rather than to Rev 2, so we're just not sure! |
027508,000002: ## Copyright: Public domain.
027509,000003: ## Filename: LAMBERT_AIMPOINT_GUIDANCE.agc
027510,000004: ## Purpose: Part of the source code for Luminary 1A build 099.
027511,000005: ## It is part of the source code for the Lunar Module's (LM)
027512,000006: ## Apollo Guidance Computer (AGC), for Apollo 11.
027513,000007: ## Assembler: yaYUL
027514,000008: ## Contact: Ron Burkey <info@sandroid.org>.
027515,000009: ## Website: www.ibiblio.org/apollo.
027516,000010: ## Pages: 651-653
027517,000011: ## Mod history: 2009-05-18 RSB Transcribed from Luminary 099
027518,000012: ## page images.
027519,000013: ## 2009-06-05 RSB Corrected 4 typos.
027520,000014: ## 2009-06-07 RSB Fixed a typo.
027521,000015: ## 2016-12-14 RSB VNP00H -> VNPOOH.
027522,000016: ## 2016-12-14 RSB Proofed text comments with octopus/ProoferComments
027523,000017: ## and corrected the errors found.
027524,000018: ## 2017-03-03 RSB Snapshot of Luminary 99 Rev 1.
027525,000019:
|
|
Page 651 |
027527,000021:
027528,000022: # GENERAL LAMBERT AIMPOINT GUIDANCE **
027529,000023: # WRITTEN BY RAMA M AIYAWAR
027530,000024:
027531,000025: # PROGRAM P-31 DESCRIPTION **
027532,000026:
027533,000027: # 1. TO ACCEPT TARGETING PARAMETERS OBTAINED FROM A SOURCE EXTERNAL
027534,000028: # TO THE LEM AND COMPUTE THERE FROM THE REQUIRED-VELOCITY AND
027535,000029: # OTHER INITIAL CONDITIONS REQUIRED BY LM FOR DESIRED MANEUVER.
027536,000030: # THE TARGETING PARAMETERS ARE TIG (TIME OF IGNITION), TARGET
027537,000031: # VECTOR (RTARG), AND THE TIME FROM TIG UNTIL THE TARGET IS
027538,000032: # REACHED (DELLT4), DESIRED TIME OF FLIGHT FROM RINIT TO RTARG..
027539,000033:
027540,000034: # ASSUMPTIONS **
027541,000035:
027542,000036: # 1. THE TARGET PARAMETERS MAY HAVE BEEN LOADED PRIOR TO THE
027543,000037: # EXECUTION OF THIS PROGRAM.
027544,000038: # 2. THIS PROGRAM IS APPLICABLE IN EITHER EARTH OR LUNAR ORBIT.
027545,000039: # 3. THIS PROGRAM IS DESIGNED FOR ONE-MAN OPERATION, AND SHOULD
027546,000040: # BE SELECTED BY THE ASTRONAUT BY DSKY ENTRY V37 E31.
027547,000041:
027548,000042: # SUBROUTINES USED **
027549,000043: #
027550,000044: # MANUPARM, TTG/N35, R02BOTH, MIDGIM, DISPMGA, FLAGDOWN, BANKCALL,
027551,000045: # GOTOPOOH, ENDOFJOB, PHASCHNG, GOFLASHR, GOFLASH.
027552,000046:
027553,000047: # MANUPARM CALCULATES APOGEE, PERIGEE ALTITUDES AND DELTAV DESIRED
027554,000048: # FOR THE MANEUVER.
027555,000049:
027556,000050: # TTG/N35 CLOCKTASK - UPDATES CLOCK.
027557,000051:
027558,000052: # MIDGIM CALCULATES MIDDLE GIMBAL ANGLE FOR DISPLAY.
027559,000053:
027560,000054: # R02BOTH IMU - STATUS CHECK ROUTINE.
027561,000055:
027562,000056: # DISPLAYS USED IN P-31LM **
027563,000057:
027564,000058: # V06N33 DISPLAY SOTRED TIG (IN HRS. MINS. SECS)
027565,000059: # V06N42 DISPLAY APOGEE, PERIGEE, DELTAV.
027566,000060: # V16N35 DISPLAY TIME FROM TIG.
027567,000061: # V06N45 TIME FROM IGNITION AND MIDDLE GIMBAL ANGLE.
027568,000062:
027569,000063: # ERASABLE INITIALIZATION REQUIRED **
027570,000064:
027571,000065: # TIG TIME OF IGNITION DP (B+28) CS.
027572,000066:
027573,000067: # DELLT4 DESIRED TIME OF FLIGHT DP (B+28) CS
027574,000068: # FROM RINIT TO RTARG.
027575,000069:
027576,000070: # RTARG RADIUS VECTOR OF TARGET POSITION VECTOR
027577,000071: # RADIUS VECTOR SCALED TO (B+29)METERS IF EARTH ORBIT
|
|
Page 652 |
027579,000073: # RADIUS VECTOR SCALED TO (B+27)METERS IF MOON ORBIT
027580,000074:
027581,000075: # OUTPUT **
027582,000076:
027583,000077: # HAPO APOGEE ALTITUDE
027584,000078: # HPER PERIGEE ALTITUDE
027585,000079: # VGDISP MAG. OF DELTAV FOR DISPLAY, SCALING B+7 M/CS EARTH
027586,000080: # MAG. OF DELTAV FOR DISPLAY, SCALING B+5 M/CS MOON
027587,000081: # MIDGIM MIDDLE GIMBAL ANGLE
027588,000082: # XDELVFLG RESETS XDELVFLG FOR LAMBERT VG COMPUTATIONS
027589,000083:
027590,000084: # ALARMS OR ABORTS NONE **
027591,000085:
027592,000086: # RESTARTS ARE VIA GROUP 4 **
027593,000087:
027594,000088: 35,2000 SETLOC GLM
027595,000089: 35,2000 BANK
027596,000090:
027597,000091: 35,2450 E7,1470 EBANK= SUBEXIT
027598,000092:
027599,000093: 35,2450 COUNT* $$/P31
027600,000094: 35,2450 02361 P31 TC P20FLGON
027601,000095: 35,2451 32025 CAF V06N33 # TIG
027602,000096: 35,2452 03712 TC VNPOOH
027603,000097: 35,2453 06037 TC INTPRET
027604,000098: 35,2454 71214 CLEAR DLOAD
027605,000099: 35,2455 00670 UPDATFLG
027606,000100: 35,2456 03442 TIG
027607,000101: 35,2457 34041 STCALL TDEC1 # INTEGRATE STATE VECTORS TO TIG
027608,000102: 35,2460 27057 LEMPREC
027609,000103: 35,2461 40375 VLOAD SETPD
027610,000104: 35,2462 00001 RATT
027611,000105: 35,2463 00001 0D
027612,000106: 35,2464 03642 STORE RTIG
027613,000107: 35,2465 26323 STOVL RINIT
027614,000108: 35,2466 00007 VATT
027615,000109: 35,2467 03650 STORE VTIG
027616,000110: 35,2470 16331 STODL VINIT
027617,000111: 35,2471 32420 P30ZERO
027618,000112: 35,2472 65206 PUSH PDDL # E4 AND NUMIT = 0
027619,000113: 35,2473 03452 DELLT4
027620,000114: 35,2474 66015 DAD SXA,1
027621,000115: 35,2475 03442 TIG
027622,000116: 35,2476 02776 RTX1
027623,000117: 35,2477 03631 STORE TPASS4
027624,000118: 35,2500 45134 SXA,2 CALL
027625,000119: 35,2501 02777 RTX2
027626,000120: 35,2502 22000 INITVEL
027627,000121: 35,2503 41575 VLOAD PUSH
|
|
Page 653 |
027629,000123: 35,2504 02366 DELVEET3
027630,000124: 35,2505 03656 STORE DELVSIN
027631,000125: 35,2506 43046 ABVAL CLEAR
027632,000126: 35,2507 01267 XDELVFLG
027633,000127: 35,2510 37664 STCALL VGDISP
027634,000128: 35,2511 15733 GET.LVC
027635,000129: 35,2512 63375 VLOAD PDVL
027636,000130: 35,2513 03642 RTIG
027637,000131: 35,2514 02337 VIPRIME
027638,000132: 35,2515 77624 CALL
027639,000133: 35,2516 46316 PERIAPO1
027640,000134: 35,2517 77624 CALL
027641,000135: 35,2520 46426 SHIFTR1
027642,000136: 35,2521 77624 CALL # LIMIT DISPLAY TO 9999.9 N. MI.
027643,000137: 35,2522 45636 MAXCHK
027644,000138: 35,2523 16321 STODL HPER
027645,000139: 35,2524 00005 4D
027646,000140: 35,2525 77624 CALL
027647,000141: 35,2526 46426 SHIFTR1
027648,000142: 35,2527 77624 CALL # LIMIT DISPLAY TO 9999.9 N. MI.
027649,000143: 35,2530 45636 MAXCHK
027650,000144: 35,2531 02317 STORE HAPO
027651,000145: 35,2532 77776 EXIT
027652,000146: 35,2533 33727 CAF V06N81 # DELVLVC
027653,000147: 35,2534 03712 TC VNPOOH
027654,000148: 35,2535 32026 CAF V06N42 # HAPO, HPER, VGDISP
027655,000149: 35,2536 03712 TC VNPOOH
027656,000150: 35,2537 06037 TC INTPRET
027657,000151: 35,2540 45014 REVN1645 SET CALL # TRKMKCNT, TTOGO, +MGA
027658,000152: 35,2541 01071 FINALFLG
027659,000153: 35,2542 73606 VN1645
027660,000154: 35,2543 77650 GOTO
027661,000155: 35,2544 72540 REVN1645
027662,000156:
End of include-file LAMBERT_AIMPOINT_GUIDANCE.agc. Parent file is MAIN.agc