Source Code
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These source-code files were transcribed from scans made from Don Eyles's personal
copy of BURST120 (SUNBURST 120). They were scanned at archive.org's Boston
facility, and the scanning was sponsored by Mike Stewart. The code was transcribed
from these scans by a team of volunteers who are referenced in the program
comments. Comments from the original source code are in ALL-CAPS, whereas
comments added later in transcription are in Mixed-Case. In some cases, where
similar code blocks exist in previously-transcribed AGC programs (primarily
Luminary 99, from Apollo 11) those code blocks were used as a starting point and
then corrected to agree with the BURST120 scans. The full scans are available
at the Virtual AGC
project's collection at archive.org, while more-convenient reduced-size (but reduced-quality)
images are available at
the main Virtual AGC website. Report any errors noted by creating an
issue report at the Virtual AGC
project's GitHub repository. Notations on the program listing read, in part:YUL SYSTEM FOR AGC: REVISION 0 OF PROGRAM BURST120 BY NASA 2021106-031 DEC 7, 1967 THIS LISTING IS A COPY OF A VERSION OF THE PROGRAM INTENDED FOR USE IN THE ON-BOARD PRIMARY GUIDANCE COMPUTER IN THE UNMANNED FLIGHT OF APOLLO LUNAR MODULE 1 --- THE AS206 MISSION.Note that the date is the date of the printout, not the date of the program revision. |
039635,000002: ## Copyright: Public domain.
039636,000003: ## Filename: THRUST_MAGNITUDE_FILTER.agc
039637,000004: ## Purpose: A module for revision 0 of BURST120 (Sunburst). It
039638,000005: ## is part of the source code for the Lunar Module's
039639,000006: ## (LM) Apollo Guidance Computer (AGC) for Apollo 5.
039640,000007: ## Assembler: yaYUL
039641,000008: ## Contact: Ron Burkey <info@sandroid.org>.
039642,000009: ## Website: www.ibiblio.org/apollo/index.html
039643,000010: ## Mod history: 2016-09-30 RSB Created draft version.
039644,000011: ## 2016-10-19 RSB Transcribed.
039645,000012: ## 2016-10-31 RSB Typos.
039646,000013: ## 2016-12-06 RSB Comment proofing via octopus/ProoferComments
039647,000014: ## performed, and changes made.
039648,000015:
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Page 923 |
039650,000017: # PROGRAM NAME - ATMAG
039651,000018:
039652,000019: # MODIFICATION BY - BERMAN AND CATTANACH
039653,000020:
039654,000021: # FUNCTIONAL DESCRIPTION -
039655,000022:
039656,000023: # THE THRUST MAGNITUDE FILTER CONVERTS ABDELV TO M/CS, INVERTS AND COMBINES IT WITH TWO PRECEDING
039657,000024: # INPUTS TO PRODUCE THE INVERTED EXHAUST VELOCITY, BURN UP TIME, AND ANTICIPATED THRUST ACCELERATION FOR
039658,000025: # THE NEXT TIME INCREMENT. THRUST MAGNITUDE FILTER IS BYPASSED UNTIL AFTER THE MAIN ENGINE GOES ON.
039659,000026:
039660,000027: # CALLING SEQUENCE - ATMAG IS ENTERED BY EXTEND AND EXTEND
039661,000028: # DCA ATMAGAD DCA ATMAG4
039662,000029: # DXCH AVGEXIT DXCH AVGEXIT
039663,000030: # NORMAL EXIT - FROM ATMAG BY GOTO
039664,000031: # ASCENT
039665,000032:
039666,000033: # OUTPUT - INVERTED EXHAUST VELOCITY, BURN UP TIME, AND ANTICIPATED THRUST ACCELERATION
039667,000034:
039668,000035: # ERASABLE INITIALIZATION REQUIRED - THIS IS DONE BY PRE-APS PROGRAMS
039669,000036:
039670,000037: # DEBRIS - ABDVCONV, 1/DV1, 1/DV2, 1/VE, TBUP, AT.
039671,000038:
039672,000039: # ALARM OR ABORT EXIT MODES -
039673,000040:
039674,000041: # SUBROUTINES CALLED - NONE
039675,000042:
039676,000043: 32,3005 BANK 32
039677,000044:
039678,000045: 32,3005 E4,1452 EBANK= TCO # EBANK4
039679,000046:
039680,000047: 32,3005 06112 ATMAG TC INTPRET
039681,000048: 32,3006 57545 DLOAD DCOMP # LOAD -VE*2(-6)
039682,000049: 32,3007 02556 NEGVEX
039683,000050: 32,3010 77742 SR1
039684,000051: 32,3011 02025 STORE VE # VE*2(-7)
039685,000052: 32,3012 67201 SETPD SLOAD
039686,000053: 32,3013 00001 00D
039687,000054: 32,3014 25052 BIT4H
039688,000055: 32,3015 77471 DDV EXIT
039689,000056: 32,3016 03624 ABDVCONV
039690,000057:
039691,000058: 32,3017 52145 DXCH MPAC
039692,000059: 32,3020 53435 DXCH 1/DV3
039693,000060: 32,3021 53433 DXCH 1/DV2
039694,000061: 32,3022 53431 DXCH 1/DV1
039695,000062: 32,3023 52145 DXCH MPAC # MPAC=1/DV0*2(-7)
039696,000063: 32,3024 06112 TC INTPRET
039697,000064: 32,3025 77615 DAD
039698,000065: 32,3026 02031 1/DV1 # (1/DV0+1/DV1)*2(-7)
039699,000066: 32,3027 43215 DAD DAD
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Page 924 |
039701,000068: 32,3030 02033 1/DV2
039702,000069: 32,3031 02035 1/DV3 # SUM(1/DV)*2(-7)
039703,000070: 32,3032 41205 DMP DMP # VE SUM(1/DV)*2(-14)
039704,000071: 32,3033 02025 VE # DT VE SUM(1/DV)*2(-21)
039705,000072: 32,3034 21400 2SEC(9)
039706,000073: 32,3035 65252 SL3 PDDL # 1/8 DT VE SUM(1/DV)*2(-17)
039707,000074: 32,3036 02027 TBUP # LOAD TBUP*2(-17)
039708,000075: 32,3037 43342 SR1 DAD # 1/2 OLD TBUP*2(-17)
039709,000076: 32,3040 77625 DSU
039710,000077: 32,3041 25053 6SEC(18) # GET NEW TBUP *2(-17)
039711,000078: 32,3042 16027 STODL TBUP
039712,000079: 32,3043 02025 VE
039713,000080: 32,3044 56342 SR1 DDV # VE*2(-8)
039714,000081: 32,3045 02027 TBUP # AT*2(9)
039715,000082: 32,3046 02023 STORE AT
039716,000083: 32,3047 77650 FILTEND GOTO
039717,000084: 32,3050 64125 ASCENT
039718,000085:
039719,000086: 32,3051 00010 BIT4H OCT 10
039720,000087: 32,3052 00045 20000 6SEC(18) 2DEC 600 B-28
039721,000088:
039722,000089: 32,3054 25715 ASCPATCH STOVL UNNORM # PATCH FROM ASCENT STEERING LOG SECTION.
039723,000090: 32,3055 02340 RCOV
039724,000091: 32,3056 52056 UNIT GOTO
039725,000092: 32,3057 64327 ENDPATCH
End of include-file THRUST_MAGNITUDE_FILTER.agc. Parent file is MAIN.agc