Assembly listing generated by yaYUL

Source Code

These source-code files are part of a reconstructed copy of Comanche 72, the first release of the Apollo Guidance Computer (AGC) Command Module (CM) software for Apollo 13.

They have been adapted from sources files created from a listing of Comanche 55. These source files were updated to match binary dumps of a set of Comanche 67 rope modules. They were then further modified by applying known changes between Comanche 67 and Comanche 72. A binary dump of module B2 of Comanche 72, part number 2010802-021, was also used to validate changes made to banks 05-13. The resulting code assembles to have identical memory-bank checksums as those specified in NASA drawing 2021153G; this gives reasonably high confidence that the changes that have been made are correct. In places where ambiguity exists, this ambiguity is discussed in "## Reconstruction:" comments.

Since no contemporary listings of Comanche 72 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.

017528,000002: 017529,000003: 017530,000004: 017531,000005: 017532,000006: 017533,000007: 017534,000008: 017535,000009: 017536,000010: 017537,000011: 017538,000012: 017539,000013: 017540,000014: 017541,000015: 017542,000016: 017543,000017: 017544,000018: 017545,000019: 017546,000020: 017547,000021: 017548,000022: 017549,000023: 017550,000024: 15,2000 017551,000025: 017552,000026: 22,2000 017553,000027: 22,2000 017554,000028: 017555,000029: 22,3026 E6,1661 017556,000030: 017557,000031: 22,3026 017558,000032: ## Copyright: Public domain. ## Filename: KALCMANU_STEERING.agc ## Purpose: A section of Comanche revision 072. ## It is part of the reconstructed source code for the first ## release of the software for the Command Module's (CM) Apollo ## Guidance Computer (AGC) for Apollo 13. No original listings ## of this program are available; instead, this file was recreated ## from a printout of Comanche 055, binary dumps of a set of ## Comanche 067 rope modules, and changelogs between Comanche 067 ## and 072. It has been adapted such that the resulting bugger words ## exactly match those specified for Comanche 072 in NASA drawing ## 2021153G, which gives relatively high confidence that the ## reconstruction is correct. ## Assembler: yaYUL ## Contact: Ron Burkey <info@sandroid.org>. ## Website: www.ibiblio.org/apollo/index.html ## Mod history: 2024-05-13 MAS Created from Comanche 067. # GENERATION OF STEERING COMMANDS FOR DIGITAL AUTOPILOT FREE FALL MANEUVERS # NEW COMMANDS WILL BE GENERATED EVERY ONE SECOND DURING THE MANEUVER BANK 15 SETLOC KALCMON1 BANK EBANK= BCDU COUNT 22/KALC 849">017559,000033: 22,3026 41332 NEWDELHI CS HOLDFLAG # SEE IF MANEUVER HAS BEEN INTERRUPTED 00006 EXTEND # BY ASTRONAUT 62726 BZMF NOGO -2 # IF SO, TERMINATE KALCMANU C">017562,000036: 22,3031 06006 NEWANGL TC INTPRET 75160 AXC,1 AXC,2 03320 MIS # COMPUTE THE NEW MATRIX FROM S/C TO 03425 DEL # STABLE MEMBER AXES 77624 CALL 44304 MXM3 45575 VLOAD STADR 50442 STOVL MIS +12D # CALCULATE NEW DESIRED CDU ANGLES 77626 STADR 50450 STOVL MIS +6D 77626 STADR 74456 STORE MIS 45160 AXC,1 CALL 03320 MIS 44655 DCMTOCDU # PICK UP THE NEW CDU ANGLES FROM MATRIX 77634 RTB 45552 V1STO2S 03267 STORE NCDU # NEW CDU ANGLES 77414 BONCLR EXIT 01215 CALCMAN2 40065 MANUSTAT # TO START MANEUVER 35032 CAF TWO # +0 OTHERWISE 455">017584,000058: 22,3057 55664 INCRDCDU TS KSPNDX 60000 DOUBLE 55665 TS KDPNDX 51664 INDEX KSPNDX 31666 CA NCDU # NEW DESIRED CDU ANGLES 00006 EXTEND 51664 INDEX KSPNDX 21661 MSU BCDU # INITIAL S/C ANGLE OR PREVIOUS DESIRED 00006 EXTEND # CDU ANGLES 73002 MP QUADROT 51665 INDEX KDPNDX 53576 DXCH DELCDUX # ANGLE INCREMENTS TO BE ADDED TO 51664 INDEX KSPNDX # DCDU EVERY TENTH SEC 31666 CA NCDU # BY LEM DAP 51664 INDEX KSPNDX 57661 XCH BCDU 51665 INDEX KDPNDX 55646 TS CDUXD 11664 CCS KSPNDX 13057 TCF INCRDCDU # LOOP FOR THREE AXES 00003 RELINT # COMPARE PRESENT TIME WITH TIME TO TERMINATE MANEUVER 84B">017608,000082: 22,3104 03115 TMANUCHK TC TIMECHK 04715 TC POSTJUMP 40131 CADR CONTMANU 35033 CAF ONE 14C">017613,000087: 22,3110 05261 MANUSTAL TC WAITLIST EBANK= BCDU 02012 42066 2CADR MANUSTOP 00003 RELINT 15233 TCF ENDOFJOB B">017621,000095: 22,3115 00006 TIMECHK EXTEND 40025 DCS TIME2 53673 DXCH TTEMP 00006 EXTEND 31717 DCA TM 21673 DAS TTEMP 11672 CCS TTEMP 00002 TC Q 13127 TCF +2 13137 TCF 2NDRETRN 11673 CCS TTEMP +1 00002 TC Q 13133 TCF MANUOFF 40000 COM 6">017635,000109: 22,3133 65055 MANUOFF AD 1SEC 00006 EXTEND 63137 BZMF 2NDRETRN 24002 INCR Q 24E">017639,000113: 22,3137 24002 2NDRETRN INCR Q 24002 INCR Q 00002 TC Q SETLOC MANUSTUF BANK 154">017645,000119: 20,2065 77776 MANUSTAT EXIT # INITIALIZATION ROUTINE 00006 EXTEND # FOR AUTOMATIC MANEUVERS 30025 DCA TIME2 21717 DAS TM # TM+T0 MANEUVER COMPLETION TIME 45055 CS 1SEC 54001 TS L 45035 CS ZERO 21717 DAS TM # (TM+T0)-1 00004 INHINT 45033 CS ONE # ENABLE AUTOPILOT TO PERFORM 55332 TS HOLDFLAG # AUTOMATIC MANEUVERS 41130 CS RATEINDX # SEE IF MANEUVERING AT HIGH RATE 66211 AD SIX 00006 EXTEND 62105 BZMF HIGHGAIN 12110 TCF +4 94E">017661,000135: 20,2105 41501 HIGHGAIN CS RCSFLAGS # IF SO, SET HIGH RATE FLAG (BIT 15 OF 75015 MASK BIT15 # RCSFLAGS) 27501 ADS RCSFLAGS 53711 DXCH BRATE # X-AXIS MANEUVER RATE 53526 DXCH WBODY 53713 DXCH BRATE +2 # Y-AXIS MANEUVER RATE 53530 DXCH WBODY1 53715 DXCH BRATE +4 # Z-AXIS MANEUVER RATE 53532 DXCH WBODY2 31675 CA BIASTEMP +1 # INSERT ATTITUDE ERROR BIASES 55564 TS BIAS # INTO AUTOPILOT 31677 CA BIASTEMP +3 55565 TS BIAS1 31701 CA BIASTEMP +5 55566 TS BIAS2 30025 CA TIME1 65055 AD 1SEC 57671 XCH NEXTIME 04715 TC POSTJUMP 45056 CADR INCRDCDU -1 E55">017682,000156: 20,2131 00004 CONTMANU INHINT # CONTINUE WITH UPDATE PROCESS 40025 CS TIME1 61671 AD NEXTIME 10000 CCS A 65033 AD ONE 12141 TCF MANUCALL 65015 AD NEGMAX 40000 COM C4C">017690,000164: 20,2141 05261 MANUCALL TC WAITLIST EBANK= BCDU 02150 40066 2CADR UPDTCALL 00003 RELINT 35055 CAF 1SEC # INCREMENT TIME FOR NEXT UPDATE 27671 ADS NEXTIME 15233 TCF ENDOFJOB C4C">017700,000174: 20,2150 37663 UPDTCALL CAF PRIO26 # CALL FOR UPDATE 05163 TC FINDVAC # OF STEERING COMMANDS EBANK= BCDU 03026 44066 2CADR NEWDELHI 05340 TC TASKOVER # ROUTINE FOR TERMINATING AUTOMATIC MANEUVERS SETLOC KALCMON3 BANK F50">017712,000186: 21,2012 04537 MANUSTOP TC STOPYZ 04754 TC IBNKCALL 45144 CADR LOADYZ C">017716,000190: 21,2015 31155 ENDROLL CA CPHI 55646 TS CDUXD # SET CDUXD TO THE COMMANDED OUTER GIMBAL 04526 TC STOPRATE 5">017719,000193: 21,2020 31327 ENDMANU CA ATTPRIO # RESTORE USERS PRIORITY 54063 TS NEWPRIO 35035 CA ZERO # ZERO ATTCADR 53326 DXCH ATTCADR 05174 TC SPVAC # RETURN TO USER OF GOMANUR 05340 TC TASKOVER SETLOC STOPRAT BANK 445">017731,000205: 4526 35035 STOPRATE CAF ZERO 55575 TS DELCDUX 55576 TS DELCDUX +1 # ZERO ROLL INCREMENTAL ANGLES 55525 TS WBODY # RATE 55526 TS WBODY +1 55564 TS BIAS # BIAS 45015 CS BIT15 # MAKE SURE HIGH RATE FLAG (BIT 15 OF 71501 MASK RCSFLAGS # RCSFLAGS) IS RESET. 55501 TS RCSFLAGS >017742,000216: 4537 35035 STOPYZ CAF ZERO 55577 TS DELCDUY # ZERO PITCH, YAW 55600 TS DELCDUY +1 # INCREMENTAL ANGLES 55601 TS DELCDUZ 55602 TS DELCDUZ +1 55527 TS WBODY1 # RATES 55530 TS WBODY1 +1 55531 TS WBODY2 55532 TS WBODY2 +1 55565 TS BIAS1 # BIASES 55566 TS BIAS2 00002 TC Q SETLOC MANUSTUF BANK F52">017758,000232: 20,2155 30032 ZEROEROR CA CDUX # PICK UP CDU ANGLES AND STORE IN 55646 TS CDUXD # CDU DESIRED 30033 CA CDUY 55650 TS CDUYD 30034 CA CDUZ 55652 TS CDUZD 00002 TC Q SETLOC KALCMON1 BANK 544">017769,000243: 22,3142 31155 LOADCDUD CA CPHI # STORE TERMINAL ANGLES INTO 55646 TS CDUXD # COMMAND ANGLES >017771,000245: 22,3144 31156 LOADYZ CA CTHETA 55650 TS CDUYD 31157 CA CPSI 55652 TS CDUZD 00002 TC Q KALCMANU_STEERING.agc. Parent file is MAIN.agc