Assembly listing generated by yaYUL

Source Code

These source code files are a reconstruction of Sundance, the Apollo 9 LM (Lunar Module) AGC (Apollo Guidance Computer) flight software, created from binary dumps of original core rope program modules, as follows:

B1 — Revision 292
B2 — Revision 302
B3 — Revision 302
B4 — Revision 302
B5 — Revision 292
B6 — Revision 306

This means that source code does not represent a specific historical revision of Sundance, but rather a mixture of the three released versions. Nonetheless, it is capable of flying the whole Apollo 9 mission. This source code matches the binary dumps, as closely as feasible, but 100% match is not possible, due mostly to changes in memory addresses at which code and variables were allocated in different revisions of Sundance. Refer to this list of explanations for each binary mismatch.

Since only binary dumps (rather than listings) of Sundance are available as source material, all comments and labels are approximate. They have been taken from other AGC programs where possible, or, in some places, written from scratch to match what we believe would have been in the original listing.

030903,000002: 030904,000003: 030905,000004: 030906,000005: 030907,000006: 030908,000007: 030909,000008: 030910,000009: 030911,000010: 030912,000011: 030913,000012: 030914,000013: 030915,000014: 030916,000015: 030917,000016: 030918,000017: 32,2671 030919,000018: 32,2000 030920,000019: 32,2000 030921,000020: 030922,000021: 32,2671 E7,1606 030923,000022: 030924,000023: 030925,000024: 030926,000025: 030927,000026: 030928,000027: 32,2671 030929,000028: < 030931,000030: 32,2672 030932,000031: 030933,000032: 32,2673 030934,000033: 32,2674 030935,000034: 030936,000035: 32,2675 030937,000036: 32,2676 030938,000037: 030939,000038: 32,2677 030940,000039: 32,2700 030941,000040: 32,2701 030942,000041: 030943,000042: < < < < 031133,000232: 031134,000233: 031135,000234: 031136,000235: 031137,000236: 031138,000237: 031139,000238: 031140,000239: 31,2000 031141,000240: 31,2000 031142,000241: 31,2000 031143,000242: 031144,000243: 31,2000 031145,000244: < 031205,000304: 031206,000305: 031207,000306: 031208,000307: 031209,000308: ## Copyright: Public domain. ## Filename: THE_LUNAR_LANDING.agc ## Purpose: A section of a reconstructed, mixed version of Sundance ## It is part of the reconstructed source code for the Lunar ## Module's (LM) Apollo Guidance Computer (AGC) for Apollo 9. ## No original listings of this program are available; ## instead, this file was created via disassembly of dumps ## of various revisions of Sundance core rope modules. ## Assembler: yaYUL ## Contact: Ron Burkey <info@sandroid.org>. ## Website: www.ibiblio.org/apollo/index.html ## Mod history: 2020-06-17 MAS Created from Luminary 69. ## Sundance 292 BANK 32 SETLOC F2DPS*32 BANK EBANK= E2DPS # **************************************** # P63: THE LUNAR LANDING, BRAKING PHASE # **************************************** COUNT* $$/P63 /a>030930,000029: 32,2671 05413 P63LM TC PHASCHNG 04024 OCT 04024 04655 TC BANKCALL # DO IMU STATUS CHECK ROUTINE R02 11064 CADR R02BOTH 33114 CAF P63ADRES # INITIALIZE WHICH FOR BURNBABY 55430 TS WHICH 33115 CAF IGNADRES # INITIALIZE WCHPHASE AND FLPASSO 22007 ZL # FOR IGNITION ALGORITHM 53607 DXCH WCHPHASE 759">030944,000043: 32,2702 06014 FLAGORGY TC INTPRET # DIONYSIAN FLAG WAVING 43014 CLEAR CLEAR 02663 NOTHROTL 02671 3AXISFLG 43014 CLEAR CLEAR 00264 VINHFLG 00676 HINHFLG 43014 SET SET 03464 SWANDISP 03067 MUNFLAG # **************************************** 1">030957,000056: 32,2714 77201 IGNALG1 SETPD VLOAD # FIRST SET UP INPUTS FOR RP-TO-R:- 00001 0 # AT 0D LANDING SITE IN MOON FIXED FRAME 02025 RLS # AT 6D ESTIMATED TIME OF LANDING 41525 PDDL PUSH # MPAC NON-ZERO TO INDICATE LUNAR CASE 02021 TLAND 37612 STCALL TPIP # ALSO SET TPIP FOR FIRST GUIDANCE PASS 51220 RP-TO-R 64312 VSL4 MXV 01736 REFSMMAT 17630 STODL LAND 02021 TLAND 77625 DSU 25120 GUIDDURN 34041 STCALL TDEC1 # INTEGRATE STATE FORWARD TO THAT TIME 27030 LEMPREC 64375 VLOAD MXV 23672 WMREF 01736 REFSMMAT 17622 STODL WM 23672 WMREF 03656 STORE NIGNLOOP 03636 STORE TTF/8 F50">030980,000079: 32,2742 77745 IGNALOOP DLOAD 00015 TAT 25234 STOVL PIPTIME 00025 VATT1 01543 STORE VCV 74521 MXV VSR1 01736 REFSMMAT 27504 STOVL V 00017 RATT1 01535 STORE RCV 64312 VSL4 MXV 01736 REFSMMAT 37476 STCALL R 67200 MUNGRAV 35236 STCALL GDT/2 62474 ?GUIDSUB # WHICH DELIVERS N PASSES OF GUIDANCE # DDUMCALC IS PROGRAMMED AS FOLLOWS:- # 2 - # (RIGNZ - RGU )/16 + 16(RGU )KIGNY/B8 + (RGU - RIGNX)KIGNX/B4 + (ABVAL(VGU) - VIGN)KIGNV/B4 # 2 1 0 # DDUM = ------------------------------------------------------------------------------------------- # 10 # 2 (VGU - 16 VGU KIGNX/B4) # 2 0 # THE NUMERATOR IS SCALED IN METERS AT 2(28). THE DENOMINATOR IS A VELOCITY IN UNITS OF 2(10) M/CS. # THE QUOTIENT IS THUS A TIME IN UNITS OF 2(18) CENTISECONDS. THE FINAL SHIFT RESCALES TO UNITS OF 2(28) CS. # THERE IS NO DAMPING FACTOR. THE CONSTANTS KIGNX/B4, KIGNY/B8 AND KIGNV/B4 ARE ALL NEGATIVE IN SIGN. C43">031009,000108: 32,2762 45345 DDUMCALC DLOAD DSU # FORM DENOMINATOR FIRST 25130 RIGNZ 03536 RGU +4 63525 PDDL DSQ 03534 RGU +2 65275 DMPR PDDL 25134 KIGNY 03532 RGU 56225 DSU DDV 25126 RIGNX 25132 1/KIGNX 51515 PDVL ABVAL 03614 VGU 57225 DSU DMPR 25124 VIGN 25136 KIGNV 43215 DAD DAD 44415 DAD SR4R 54271 DDV SRR 03620 VGU +4 21615 12D 43206 PUSH DAD 01234 PIPTIME 14041 STODL TDEC1 # STORE NEW GUESS FOR NEXT INTEGRATION 45246 ABS DSU 25122 DDUMCRIT 45040 BMN CALL 65031 DDUMGOOD 27362 INTSTALL 43014 SET SET 01473 INTYPFLG 00063 MOONFLAG 71214 CLEAR DLOAD 00262 MIDFLAG 01234 PIPTIME 35517 STCALL TET 27060 INTEGRVS 77650 GOTO 64742 IGNALOOP F44">031050,000149: 32,3031 45345 DDUMGOOD DLOAD DSU 00041 TDEC1 03421 ZOOMTDP 27425 STOVL TIG # COMPUTE DISTANCE LANDING SITE WILL BE 03476 R # OUT OF LM'S ORBITAL PLANE AT IGNITION: 53435 VXV UNIT # SIGN IS + IF LANDING SITE IS TO THE 03504 V # RIGHT, NORTH; - IF TO THE LEFT, SOUTH. 72441 DOT SL1 03630 LAND 4">031059,000158: 32,3042 26427 R60INIT STOVL OUTOFPLN # INITIALIZATION FOR CALCMANU 03250 UNFC/2 25256 STOVL POINTVSM 06231 UNITX 01250 STORE SCAXIS 77776 EXIT # **************************************** 254">031067,000166: 32,3050 05413 IGNALGRT TC PHASCHNG # PREVENT REPEATING IGNALG 04024 OCT 04024 04655 TC BANKCALL 75053 CADR GOASTCLK 35743 CAF OCT14 04655 TC BANKCALL 20532 CADR GOPERF1 14106 TCF GOTOPOOH 13062 TCF P63SPOT2 13066 TCF +5 432">031080,000179: 32,3062 06014 P63SPOT2 TC INTPRET 77624 CALL 30317 R51 77776 EXIT 00004 INHINT 04737 TC IBNKCALL 40223 CADR PFLITEDB 00003 RELINT 04655 TC BANKCALL 54103 CADR R60LEM 05413 TC PHASCHNG # PREVENT RECALLING R60 04024 OCT 04024 433">031096,000195: 32,3076 35021 P63SPOT3 CA BIT6 # IS THE LR ANTENNA IN POSITION 1 YET 00006 EXTEND 02033 RAND CHAN33 00006 EXTEND 13110 BZF P63SPOT4 # BRANCH IF ANTENNA ALREADY IN POSITION 1 33116 CAF CODE500 # ASTRONAUT: PLEASE CRANK THE 04655 TC BANKCALL # SILLY THING AROUND 20532 CADR GOPERF1 14106 TCF GOTOPOOH # TERMINATE 13076 TCF P63SPOT3 # PROCEED SEE IF HE'S LYING 434">031108,000207: 32,3110 04655 P63SPOT4 TC BANKCALL # ENTER INITIALIZE LANDING RADAR 67665 CADR SETPOS1 04674 TC POSTJUMP # OFF TO SEE THE WIZARD ... 74133 CADR BURNBABY # ---------------------------------------- # CONSTANTS FOR P63LM AND IGNALG 553">031118,000217: 32,3114 02061 P63ADRES GENADR P63TABLE 553">031120,000219: 32,3115 02417 IGNADRES GENADR IGNALG 0">031122,000221: 32,3116 00500 CODE500 OCT 00500 24E">031124,000223: 32,3117 00003 26600 GUIDDURN 2DEC +60800 B-28 954">031125,000224: 32,3121 00000 00024 DDUMCRIT 2DEC +20 B-28 # CRITERION FOR IGNALG CONVERGENCE >031127,000226: 32,3123 00417 16641 VIGN 2DEC* +1.69664345 E+1 B-10* /a>031128,000227: 32,3125 77736 63511 RIGNX 2DEC* -3.41873750 E+4 B-24* /a>031129,000228: 32,3127 77126 65060 RIGNZ 2DEC* -4.35548938 E+5 B-24* 8">031130,000229: 32,3131 71463 46314 1/KIGNX 2DEC* -1.99999999 E-1 B+0* /a>031131,000230: 32,3133 77777 74571 KIGNY 2DEC* -0.02430170 E-6 B+8* /a>031132,000231: 32,3135 76647 77777 KIGNV 2DEC -384 E2 B-20 # ---------------------------------------- # **************************************** # LANDING CONFIRMATION # **************************************** BANK 31 SETLOC F2DPS*31 BANK COUNT* $$/P6567 E4B">031146,000245: 31,2000 05563 LANDJUNK TC UPFLAG 00175 ADRES FLUNDISP 03562 TC FASTCHNG 05413 TC PHASCHNG 00005 OCT 00005 00004 INHINT 04737 TC IBNKCALL 75561 CADR ENGINOF3 05563 TC UPFLAG 22371 CADR LRBYPASS 06014 TC INTPRET # TO INTERPRETIVE AS TIME IS NOT CRITICAL 72234 RTB TLOAD 30653 RDCDUS 00002 1D 03233 STORE CDUXD 43014 SET SET 04067 SURFFLAG 03072 KILLROSE 43014 CLEAR CLEAR 03672 AVEGFLAG 03664 SWANDISP 72575 VLOAD VSL2 01220 RN 16034 STODL ALPHAV 01234 PIPTIME 45014 SET CALL 01463 LUNAFLAG 26323 LAT-LONG 77201 SETPD VLOAD # COMPUTE RLS AND STORE IT AWAY 00001 0 01220 RN 65352 VSL2 PDDL 01234 PIPTIME 45006 PUSH CALL 51245 R-TO-RP 02025 STORE RLS 77776 EXIT 32062 CAF V06N43* # ASTRONAUT: NOW LOOK WHERE YOU ENDED UP 04655 TC BANKCALL 20406 CADR GOFLASH 14106 TCF GOTOPOOH # TERMINATE 12053 TCF +2 # PROCEED 12045 TCF -5 # RECYCLE 32063 CAF OCT501 04655 TC BANKCALL 20532 CADR GOPERF1 14106 TCF GOTOPOOH 12061 TCF +2 12053 TCF -5 14106 TCF GOTOPOOH # ASTRONAUT: PLEASE SELECT P57 A">031202,000301: 31,2062 01453 V06N43* VN 0643 >031203,000302: 31,2063 00501 OCT501 OCT 501 /a>031204,000303: 31,2064 00071 OCT71 OCT 71 # **************************************** # LANDING TEST PROGRAM # **************************************** 354">031210,000309: 31,2065 32234 LANDTEST CA VERTADR 55606 TS WCHPHASE 55607 TS FLPASS0 55656 TS WCHVERT 06014 TC INTPRET 64375 VLOAD MXV 23672 WMREF 01736 REFSMMAT 17622 STODL WM 35122 LUNLANAD 25253 STOVL AVEGEXIT 03532 RGU 74256 UNIT VXSC 22167 LANDSCAL 03630 STORE LAND 43046 ABVAL SET 03470 IDLEFLAG 26023 STOVL /LAND/ 06231 UNITX 26401 STOVL CG 06227 UNITY 26407 STOVL CG +6 06225 UNITZ 02415 STORE CG +12D 47014 SET RTB 03067 MUNFLAG 21454 LOADTIME 03612 STORE TPIP 77776 EXIT 00004 INHINT 35026 CAF ONE 05252 TC WAITLIST EBANK= DVCNTR 02000 66067 2CADR PREREAD 35012 CAF BIT13 00006 EXTEND 02011 RAND DSALMOUT 10000 CCS A 12144 TCF TSTENGON 04737 TC IBNKCALL 74647 CADR ONULLAGE 35052 CAF 3SECS 05243 TC TWIDDLE 02155 ADRES TESTIGN 35054 CAF LOW9 04655 TC BANKCALL 01730 CADR DELAYJOB F4E">031264,000363: 31,2144 00004 TSTENGON INHINT 45017 CS DRIFTBIT 71102 MASK DAPBOOLS 55102 TS DAPBOOLS 35030 CAF ZERO 55607 TS FLPASS0 32170 CAF TESTDB 55356 TS DB 15225 TCF ENDOFJOB E">031276,000375: 31,2155 44367 TESTIGN CS PRIO30 00006 EXTEND 02011 RAND DSALMOUT 65012 AD BIT13 00006 EXTEND 01011 WRITE DSALMOUT 05563 TC UPFLAG 00123 ADRES ENGONFLG 15321 TCF TASKOVER 14C">031286,000385: 31,2166 06502 26500 LANDSCAL 2DEC 0.207196475 >031287,000386: 31,2170 00554 TESTDB DEC 0.02222 THE_LUNAR_LANDING.agc. Parent file is MAIN.agc