Source Code
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This is a reconstruction of the AGC program Luminary 99 Rev 0. It was the third release
of the Lunar Module flight software targeted for use in Apollo 11, after Luminary 96 and 97.
A bug (which had been around since at least Apollo 10, Luminary 69) was
discovered in Rev 0 shortly before the Apollo 11 flight, resulting in a last minute
revision into Rev 1,
which is what actually flew rather than
the Rev 0 presented here. A hardcopy of Rev 0 is known to
exist — it belonged to AGC developer Allan Klumpp for many years — but
unfortunately the Virtual AGC Project has not had access to that hardcopy. Thus
the code you see here had been reconstructed (we believe accurately) rather than
transcribed. The first step of the reconstruction of the Rev 0 source code was
the transcription of the Rev 1 source code from a hardcopy in the MIT Museum collection.
The process of reverting the active portion of the source code (i.e., other than
program comments) from Rev 1 to Rev 0 was very minor, consisting
only of moving the position of the STARTSB1 label in
FRESH START AND RESTART. Allan had previously given
us the checksums of the memory banks of Rev 0, and we have verified the program presented here has checksums
identical to all banks of Allan's listing of Rev 0. The notations on Allan's Rev 0 program listing read,
in part:GAP: ASSEMBLE REVISION 099 OF AGC PROGRAM LUMINARY BY NASA 2021112-051 A single program comment is known to differ between Rev 0 and Rev 1, but these are harder to reconstruct and verify than changes to the active portion of the code. Thus it is possible that there are additional differences between the program comments in Rev 0 and Rev 1 that are unknown to us, and therefore are not reflected in the code presented here. |
061600,000002: ## Copyright: Public domain.
061601,000003: ## Filename: DAP_INTERFACE_SUBROUTINES.agc
061602,000004: ## Purpose: Part of the reconstructed source code for LMY99 Rev 0,
061603,000005: ## otherwise known as Luminary Rev 99, the third release
061604,000006: ## of the Apollo Guidance Computer (AGC) software for Apollo 11.
061605,000007: ## It differs from LMY99 Rev 1 (the flown version) only in the
061606,000008: ## placement of a single label. The corrections shown here have
061607,000009: ## been verified to have the same bank checksums as AGC developer
061608,000010: ## Allan Klumpp's copy of Luminary Rev 99, and so are believed
061609,000011: ## to be accurate. This file is intended to be a faithful
061610,000012: ## recreation, except that the code format has been changed to
061611,000013: ## conform to the requirements of the yaYUL assembler rather than
061612,000014: ## the original YUL assembler.
061613,000015: ##
061614,000016: ## Assembler: yaYUL
061615,000017: ## Contact: Ron Burkey <info@sandroid.org>.
061616,000018: ## Website: www.ibiblio.org/apollo.
061617,000019: ## Pages: 1406-1409
061618,000020: ## Mod history: 2009-05-10 SN (Sergio Navarro). Started adapting
061619,000021: ## from the Luminary131/ file of the same
061620,000022: ## name, using Luminary099 page images.
061621,000023: ## 2011-01-06 JL Fixed pseudo-label indentation.
061622,000024: ## 2016-12-18 RSB Proofed text comments with octopus/ProoferComments
061623,000025: ## and corrected the errors found.
061624,000026: ## 2017-03-10 RSB Comment-text fixes noted in proofing Luminary 116.
061625,000027: ## 2017-08-01 MAS Created from LMY99 Rev 1.
061626,000028:
061627,000029: ## This source code has been transcribed or otherwise adapted from
061628,000030: ## digitized images of a hardcopy from the MIT Museum. The digitization
061629,000031: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
061630,000032: ## the Museum. Many thanks to both. The images (with suitable reduction
061631,000033: ## in storage size and consequent reduction in image quality as well) are
061632,000034: ## available online at www.ibiblio.org/apollo. If for some reason you
061633,000035: ## find that the images are illegible, contact me at info@sandroid.org
061634,000036: ## about getting access to the (much) higher-quality images which Paul
061635,000037: ## actually created.
061636,000038: ##
061637,000039: ## The code has been modified to match LMY99 Revision 0, otherwise
061638,000040: ## known as Luminary Revision 99, the Apollo 11 software release preceeding
061639,000041: ## the listing from which it was transcribed. It has been verified to
061640,000042: ## contain the same bank checksums as AGC developer Allan Klumpp's listing
061641,000043: ## of Luminary Revision 99 (for which we do not have scans).
061642,000044: ##
061643,000045: ## Notations on Allan Klumpp's listing read, in part:
061644,000046: ##
061645,000047: ## ASSEMBLE REVISION 099 OF AGC PROGRAM LUMINARY BY NASA 2021112-51
061646,000048:
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Page 1406 |
061648,000050: 20,2123 BANK 20
061649,000051: 20,2000 SETLOC DAPS3
061650,000052: 20,2000 BANK
061651,000053:
061652,000054: 20,2123 E6,1635 EBANK= CDUXD
061653,000055: 20,2123 COUNT* $$/DAPIF
061654,000056:
061655,000057: # MOD 0 DATE 11/15/66 BY GEORGE W. CHERRY
061656,000058: # MOD 1 1/23/67 MODIFICATION BY PETER ADLER
061657,000059:
061658,000060: # FUNCTIONAL DESCRIPTION
061659,000061: # HEREIN ARE A COLLECTION OF SUBROUTINES WHICH ALLOW MISSION CONTROL PROGRAMS TO CONTROL THE MODE
061660,000062: # AND INTERFACE WITH THE DAP.
061661,000063:
061662,000064: # CALLING SEQUENCES
061663,000065: # IN INTERRUPT OR WITH INTERRUPT INHIBITED
061664,000066: # TC IBNKCALL
061665,000067: # FCADR ROUTINE
061666,000068: # IN A JOB WITHOUT INTERRUPT INHIBITED
061667,000069: # INHINT
061668,000070: # TC IBNKCALL
061669,000071: # FCADR ROUTINE
061670,000072: # RELINT
061671,000073:
061672,000074: # OUTPUT
061673,000075: # SEE INDIVIDUAL ROUTINES BELOW
061674,000076:
061675,000077: # DEBRIS
061676,000078: # A, L, AND SOMETIMES MDUETEMP ODE NOT IN PULSES MODE
061677,000079:
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Page 1407 |
061679,000081: # SUBROUTINE NAMES:
061680,000082: # SETMAXDB, SETMINDB, RESTORDB, PFLITEDB
061681,000083: # MODIFIED: 30 JANUARY 1968 BY P S WEISSMAN TO CREATE RESTORDB.
061682,000084: # MODIFIED: 1 MARCH 1968 BY P S WEISSMAN TO SAVE EBANK AND CREATE PFLITEDB
061683,000085:
061684,000086: # FUNCTIONAL DESCRIPTION:
061685,000087: # SETMAXDB - SET DEADBAND TO 5.0 DEGREES
061686,000088: # SETMINDB - SET DEADBAND TO 0.3 DEGREE
061687,000089: # RESTORDB - SET DEADBAND TO MAX OR MIN ACCORDING TO SETTING OF DBSELECT BIT OF DAPBOOLS
061688,000090: # PFLITEDB - SET DEADBAND TO 1.0 DEGREE AND ZERO THE COMMANDED ATTITUDE CHANGE AND COMMANDED RATE
061689,000091:
061690,000092: # ALL ENTRIES SET UP A NOVAC JOB TO DO 1/ACCS SO THAT THE TJETLAW SWITCH CURVES ARE POSITIONED TO
061691,000093: # REFLECT THE NEW DEADBAND. IT SHOULD BE NOTED THAT THE DEADBAND REFERS TO THE ATTITUDE IN THE P-, U-, AND V-AXES.
061692,000094:
061693,000095: # SUBROUTINE CALLED: NOVAC
061694,000096:
061695,000097: # CALLING SEQUENCE: SAME AS ABOVE
061696,000098: # OR TC RESTORDB +1 FROM ALLCOAST
061697,000099:
061698,000100: # DEBRIS: A, L, Q, RUPTREG1, (ITEMPS IN NOVAC)
061699,000101:
061700,000102: 20,2123 30111 RESTORDB CAE DAPBOOLS # DETERMINE CREW-SELECTED DEADBAND.
061701,000103: 20,2124 74750 MASK DBSELECT
061702,000104: 20,2125 00006 EXTEND
061703,000105: 20,2126 12140 BZF SETMINDB
061704,000106:
061705,000107: 20,2127 32151 SETMAXDB CAF WIDEDB # SET 5 DEGREE DEADBAND.
061706,000108: 20,2130 55346 +1 TS DB
061707,000109:
061708,000110: 20,2131 00006 EXTEND # SET UP JOB TO RE-POSITION SWITCH CURVES.
061709,000111: 20,2132 22070 QXCH RUPTREG1
061710,000112: 20,2133 37715 CALLACCS CAF PRIO27
061711,000113: 20,2134 05072 TC NOVAC
061712,000114: 20,2135 E6,1537 EBANK= AOSQ
061713,000115: 20,2135 02454 40106 2CADR 1/ACCJOB
061714,000116:
061715,000117: 20,2137 00070 TC RUPTREG1 # RETURN TO CALLER.
061716,000118:
061717,000119: 20,2140 32150 SETMINDB CAF NARROWDB # SET 0.3 DEGREE DEADBAND.
061718,000120: 20,2141 12130 TCF SETMAXDB +1
061719,000121:
061720,000122: 20,2142 00006 PFLITEDB EXTEND # THE RETURN FROM CALLACCS IS TO RUPTREG1.
061721,000123: 20,2143 22070 QXCH RUPTREG1
061722,000124: 20,2144 02153 TC ZATTEROR # ZERO THE ERRORS AND COMMANDED RATES.
061723,000125: 20,2145 32152 CAF POWERDB # SET DB TO 1.0 DEG.
061724,000126: 20,2146 55346 TS DB
061725,000127: 20,2147 12133 TCF CALLACCS # SET UP 1/ACCS AND RETURN TO CALLER.
061726,000128: 20,2150 00155 NARROWDB OCTAL 00155 # 0.3 DEGREE SCALED AT 45.
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Page 1408 |
061728,000130: 20,2151 03434 WIDEDB OCTAL 03434 # 5.0 DEGREES SCALED AT 45.
061729,000131: 20,2152 00554 POWERDB DEC .02222 # 1.0 DEGREE SCALED AT 45.
061730,000132:
061731,000133: 20,2153 35015 ZATTEROR CAF EBANK6
061732,000134: 20,2154 56003 XCH EBANK
061733,000135: 20,2155 54001 TS L # SAVE CALLERS EBANK IN L.
061734,000136: 20,2156 30032 CAE CDUX
061735,000137: 20,2157 55635 TS CDUXD
061736,000138: 20,2160 30033 CAE CDUY
061737,000139: 20,2161 55636 TS CDUYD
061738,000140: 20,2162 30034 CAE CDUZ
061739,000141: 20,2163 55637 TS CDUZD
061740,000142: 20,2164 12170 TCF STOPRATE +3
061741,000143:
061742,000144: 20,2165 35015 STOPRATE CAF EBANK6
061743,000145: 20,2166 56003 XCH EBANK
061744,000146: 20,2167 54001 TS L # SAVE CALLERS EBANK IN L.
061745,000147: 20,2170 34755 +3 CAF ZERO
061746,000148: 20,2171 55643 TS OMEGAPD
061747,000149: 20,2172 55644 TS OMEGAQD
061748,000150: 20,2173 55645 TS OMEGARD
061749,000151: 20,2174 55640 TS DELCDUX
061750,000152: 20,2175 55641 TS DELCDUY
061751,000153: 20,2176 55642 TS DELCDUZ
061752,000154: 20,2177 55277 TS DELPEROR
061753,000155: 20,2200 55300 TS DELQEROR
061754,000156: 20,2201 55301 TS DELREROR
061755,000157: 20,2202 22003 LXCH EBANK # RESTORE CALLERS EBANK.
061756,000158: 20,2203 00002 TC Q
061757,000159:
061758,000160: # SUBROUTINE NAME: ALLCOAST
061759,000161: # WILL BE CALLED BY FRESH STARTS AND ENGINE OFF ROUTINES. .
061760,000162:
061761,000163: # CALLING SEQUENCE: (SAME AS ABOVE)
061762,000164:
061763,000165: # EXIT: RETURN TO Q.
061764,000166:
061765,000167: # SUBROUTINES CALLED: STOPRATE, RESTORDB, NOVAC
061766,000168:
061767,000169: # ZERO: (FOR ALL AXES) AOS, ALPHA, AOSTERM, OMEGAD, DELCDU, DELEROR
061768,000170:
061769,000171: # OUTPUT: DRIFTBIT/DAPBOOLS, DB, JOB TO DO 1/ACCS
061770,000172:
061771,000173: # DEBRIS: A, L, Q, RUPTREG1, RUPTREG2, (ITEMPS IN NOVAC)
061772,000174:
061773,000175: 20,2204 00006 ALLCOAST EXTEND # SAVE Q FOR RETURN
061774,000176: 20,2205 22071 QXCH RUPTREG2
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Page 1409 |
061776,000178: 20,2206 02165 TC STOPRATE # CLEAR RATE INTERFACE. RETURN WITH A=0
061777,000179: 20,2207 22003 LXCH EBANK # AND L=EBANK6. SAVE CALLERS EBANK.
061778,000180: 20,2210 55537 TS AOSQ
061779,000181: 20,2211 55540 TS AOSQ +1
061780,000182: 20,2212 55541 TS AOSR
061781,000183: 20,2213 55542 TS AOSR +1
061782,000184: 20,2214 55424 TS ALPHAQ # FOR DOWNLIST.
061783,000185: 20,2215 55425 TS ALPHAR
061784,000186: 20,2216 55545 TS AOSQTERM
061785,000187: 20,2217 55546 TS AOSRTERM
061786,000188: 20,2220 22003 LXCH EBANK # RESTORE EBANK (EBANK6 NO LONGER NEEDED)
061787,000189:
061788,000190: 20,2221 40111 CS DAPBOOLS # SET UP DRIFTBIT
061789,000191: 20,2222 74744 MASK DRIFTBIT
061790,000192: 20,2223 26111 ADS DAPBOOLS
061791,000193: 20,2224 02124 TC RESTORDB +1 # RESTORE DEADBANK TO CREW-SELECTED VALUE.
061792,000194:
061793,000195: 20,2225 00071 TC RUPTREG2 # RETURN.
061794,000196:
End of include-file DAP_INTERFACE_SUBROUTINES.agc. Parent file is MAIN.agc