# Copyright: Public domain. # Filename: RT8_OP_CODES.agc # Purpose: Part of the source code for Comanche, build 055. It # is part of the source code for the Command Module's # (CM) Apollo Guidance Computer (AGC), Apollo 11. # Assembler: yaYUL # Reference: pp. 1508-1516 # Contact: Ron Burkey <info@sandroid.org> # Website: http://www.ibiblio.org/apollo. # Mod history: 2009-05-07 RSB Adapted from Colossus249/RT8_OP_CODES.agc # and page images. # 2009-05-07 RSB Oops! Left out the entire last page before. # # The contents of the "Comanche055" files, in general, are transcribed # from scanned documents. # # Assemble revision 055 of AGC program Comanche by NASA # 2021113-051. April 1, 1969. # # This AGC program shall also be referred to as Colossus 2A # # Prepared by # Massachusetts Institute of Technology # 75 Cambridge Parkway # Cambridge, Massachusetts # # under NASA contract NAS 9-4065. # # Refer directly to the online document mentioned above for further # information. Please report any errors to info@sandroid.org. # Page 1508 BANK 22 SETLOC RTBCODES BANK EBANK= XNB COUNT* $$/RTB # LOAD TIME2, TIME1 INTO MPAC: LOADTIME EXTEND DCA TIME2 TCF SLOAD2 # CONVERT THE SINGLE PRECISION 2'S COMPLEMENT NUMBER ARRIVING IN MPAC (SCALED IN HALF-REVOLUTIONS) TO A # DP 1'S COMPLEMENT NUMBER SCALED IN REVOLUTIONS. CDULOGIC CCS MPAC CAF ZERO TCF +3 NOOP CS HALF TS MPAC +1 CAF ZERO XCH MPAC EXTEND MP HALF DAS MPAC TCF DANZIG # MODE IS ALREADY AT DOUBLE-PRECISION # READ THE PIPS INTO MPAC WITHOUT CHANGING THEM: READPIPS INHINT CA PIPAX TS MPAC CA PIPAY TS MPAC +3 CA PIPAZ RELINT TS MPAC +5 CAF ZERO TS MPAC +1 TS MPAC +4 TS MPAC +6 VECMODE TCF VMODE # FORCE TP SIGN AGREEMENT IN MPAC: SGNAGREE TC TPAGREE # Page 1509 TCF DANZIG # CONVERT THE DP 1'S COMPLEMENT ANGLE SCALED IN REVOLUTIONS TO A SINGLE PRECISION 2'S COMPLEMENT ANGLE # SCALED IN HALF-REVOLUTIONS. 1STO2S TC 1TO2SUB CAF ZERO TS MPAC +1 TCF NEWMODE # DO 1STO2S ON A VECTOR OF ANGLES: V1STO2S TC 1TO2SUB # ANSWER ARRIVES IN A AND MPAC. DXCH MPAC +5 DXCH MPAC TC 1TO2SUB TS MPAC +2 DXCH MPAC +3 DXCH MPAC TC 1TO2SUB TS MPAC +1 CA MPAC +5 TS MPAC TPMODE CAF ONE # MODE IS TP. TCF NEWMODE # V1STO2S FOR 2 COMPONENT VECTOR. USED BY RR. 2V1STO2S TC 1TO2SUB DXCH MPAC +3 DXCH MPAC TC 1TO2SUB TS L CA MPAC +3 TCF SLOAD2 # SUBROUTINE TO DO DOUBLING AND 1'S TO 2'S CONVERSION: 1TO2SUB DXCH MPAC # FINAL MPAC +1 UNSPECIFIED. DDOUBL CCS A AD ONE TCF +2 COM # THIS WAS REVERSE OF MSU. TS MPAC # AND SKIP ON OVERFLOW. # Page 1510 TC Q INDEX A # OVERFLOW UNCORRECT AND IN MSU. CAF LIMITS ADS MPAC TC Q # Page 1511 # SUBROUTINE TO INCREMENT CDUS INCRCDUS CAF LOCTHETA TS BUF # PLACE ADRES(THETA) IN BUF. CAE MPAC # INCREMENT IN 1S COMPL. TC CDUINC INCR BUF CAE MPAC +3 TC CDUINC INCR BUF CAE MPAC +5 TC CDUINC TCF VECMODE LOCTHETA ADRES THETAD # THE FOLLOWING ROUTINE INCREMENTS IN 2S COMPLEMENT THE REGISTER WHOSE ADDRESS IS IN BUF BY THE 1S COMPL. # QUANTITY FOUND IN TEM2. THIS MAY BE USED TO INCREMENT DESIRED IMU AND OPTICS CDU ANGLES OR ANY OTHER 2S COMPL. # (+0 UNEQUAL TO -0) QUANTITY. MAY BE CALLED BY BANKCALL/SWCALL. CDUINC TS TEM2 # 1S COMPL.QUANT. ARRIVES IN ACC. STORE IT INDEX BUF CCS 0 # CHANGE 2S COMPLE. ANGLE(IN BUF) INTO 1S AD ONE TCF +4 AD ONE AD ONE # OVEFLOW HERE IF 2S COMPL. IS 180 DEG. COM AD TEM2 # SULT MOVES FROM 2ND TO 3D QUAD.(OR BACK) CCS A # BACK TO 2S COMPL. AD ONE TCF +2 COM TS TEM2 # STORE 14BIT QUANTITY WITH PRESENT SIGN TCF +4 INDEX A # SIGN. CAF LIMITS # FIX IT,BY ADDING IN 37777 OR 40000 AD TEM2 INDEX BUF TS 0 # STORE NEW ANGLE IN 2S COMPLEMENT. TC Q # Page 1512 # RTB TO TORQUE GYROS, EXCEPT FOR THE CALL TO IMUSTALL. ECADR OF COMMANDS ARRIVES IN X1. PULSEIMU INDEX FIXLOC # ADDRESS OF GYRO COMMANDS SHOULD BE IN X1 CA X1 TC BANKCALL CADR IMUPULSE TCF DANZIG # Page 1513 # EACH ROUTINE TAKES A 3X3 MATRIX STORED IN DOUBLE PRECISION IN A FIXED AREA OF ERASABLE MEMORY AND REPLACES IT # WITH THE TRANSPOSE MATRIX. TRANSP1 USES LOCATIONS XNB+0,+1 THROUGH XNB+16D, 17D AND TRANSP2 USES LOCATIONS # XNB1+0,+1 THROUGH XNB1+16D, 17D. EACH MATRIX IS STORED BY ROWS. XNBEB ECADR XNB XNB1EB ECADR XNB1 EBANK= XNB TRANSP1 CAF XNBEB TS EBANK DXCH XNB +2 DXCH XNB +6 DXCH XNB +2 DXCH XNB +4 DXCH XNB +12D DXCH XNB +4 DXCH XNB +10D DXCH XNB +14D DXCH XNB +10D TCF DANZIG EBANK= XNB1 TRANSP2 CAF XNB1EB TS EBANK DXCH XNB1 +2 DXCH XNB1 +6 DXCH XNB1 +2 DXCH XNB1 +4 DXCH XNB1 +12D DXCH XNB1 +4 DXCH XNB1 +10D DXCH XNB1 +14D DXCH XNB1 +10D TCF DANZIG # Page 1514 # THE SUBROUTINE SIGNMPAC SETS C(MPAC, MPAC +1) TO SIGN(MPAC). # FOR THIS, ONLY THE CONTENTS OF MPAC ARE EXAMINED. ALSO +0 YIELDS POSMAX AND -0 YIELDS NEGMAX. # # ENTRY MAY BE BY EITHER OF THE FOLLOWING: # 1. LIMIT THE SIZE OF MPAC ON INTERPRETIVE OVERFLOW: # ENTRY: BOVB # SIGNMPAC # 2. GENERATE IN MPAC THE SIGNUM FUNCTION OF MPAC: # ENTRY: RTB # SIGNMPAC # IN EITHER CASE, RETURN IS TO TEH NEXT INTERPRETIVE INSTRUCTION IN THE CALLING SEQUENCE. SIGNMPAC EXTEND DCA DPOSMAX DXCH MPAC CCS A DPMODE CAF ZERO # SETS MPAC +2 TO ZERO IN THE PROCESS TCF SLOAD2 +2 TCF +1 EXTEND DCS DPOSMAX TCF SLOAD2 # RTB OP CODE NORMUNIT IS LIKE INTERPRETIVE INSTRUCTION UNIT, EXCEPT THAT IT CAN BE DEPENDED ON NOT TO BLOW # UP WHEN THE VECTOR BEING UNITIZED IS VERY SMALL -- IT WILL BLOW UP WHEN ALL COMPONENT ARE ZERO. IF NORMUNIT # IS USED AND THE UPPER ORDER HALVES OF ALL COMPONENTS ARE ZERO, THE MAGNITUDE RETURNS IN 36D WILL BE TOO LARGE # BY A FACTOR OF 2(13) AND THE SQUARED MAGNITUDE RETURNED AT 34D WILL BE TOO BIG BY A FACTOR OF 2(26). NORMUNX1 CAF ONE TCF NORMUNIT +1 NORMUNIT CAF ZERO AD FIXLOC TS MPAC +2 TC BANKCALL # GET SIGN AGREEMENT IN ALL COMPONENTS CADR VECAGREE CCS MPAC TCF NOSHIFT TCF +2 TCF NOSHIFT CCS MPAC +3 TCF NOSHIFT TCF +2 TCF NOSHIFT CCS MPAC +5 TCF NOSHIFT TCF +2 TCF NOSHIFT # Page 1515 CA MPAC +1 # SHIFT ALL COMPONENTS LEFT 13 EXTEND MP BIT14 DAS MPAC # DAS GAINS A LITTLE ACCURACY CA MPAC +4 EXTEND MP BIT14 DAS MPAC +3 CA MPAC +6 EXTEND MP BIT14 DAS MPAC +5 CAF THIRTEEN INDEX MPAC +2 TS 37D OFFTUNIT TC POSTJUMP CADR UNIT +1 # SKIP THE "TC VECAGREE" DONE AT UNIT NOSHIFT CAF ZERO TCF OFFTUNIT -2 # RTB VECSGNAG ...FORCES SIGN AGREEMENT OF VECTOR IN MPAC. VECSGNAG TC BANKCALL CADR VECAGREE TC DANZIG # Page 1516 # MODULE CHANGE FOR NEW LUNAR GRAVITY MODEL SETLOC MODCHG3 BANK QUALITY1 BOF DLOAD MOONFLAG NBRANCH URPV DSQ GOTO QUALITY2 SETLOC MODCHG2 BANK QUALITY2 PDDL DSQ # SQUARE INTO 2D, B2 URPV +2 # Y COMPONENT, B1 DSU DMP VXSC # 5(Y**2-X**2)UR 5/8 # CONSTANT, 5B3 URPV # VECTOR, RESULT MAXIMUM IS 5, SCALING # HERE B6 VSL3 PDDL # STORE SCALED B3 IN 2D, 4D, 6D FOR XYZ URPV # X COMPONENT, B1 SR1 DAD # 2 X X COMPONENT FOR B3 SCALING 2D # ADD TO VECTOR X COMPONENT OF ANSWER. # SAME AS MULTIPLYING BY UNITX. MAX IS 7. STODL 2D URPV +2 # Y COMPONENT, B1 SR1 BDSU # 2 X Y COMPONENT FOR B3 SCALING 4D # SUBTRACT FROM VECTOR Y COMPONENT OF # ANSWER, SAME AS MULTIPLYING BY UNITY. # MAX IS 7. STORE 4D # 2D HAS VECTOR, B3. SLOAD VXSC # MULTIPLY COEFFICIENT TIMES VECTOR IN 2D E3J22R2M PDDL RVQ # J22 TERM X R**4 IN 2D, SCALED B61 COSPHI/2 # SAME AS URPV +4, Z COMPONENT # *** END OF CHIEFTAN.028 ***