### FILE="Main.annotation"
## Copyright:    Public domain.
## Filename:     RTB_OP_CODES.agc
## Purpose:      Part of the source code for Aurora (revision 12).
## Assembler:    yaYUL
## Contact:      Ron Burkey <info@sandroid.org>.
## Website:      https://www.ibiblio.org/apollo.
## Pages:        425-430
## Mod history:  2016-09-20 JL   Created.
##               2016-10-03 JL   Transcribed pages 425-430.
##               2016-10-16 HG   Fix operand LASTXMCD -> LASTXCMD
##                                           RUPTREG12 -> RUPTREG2 
##		 2016-12-08 RSB	 Proofed comments with octopus/ProoferComments
##				 and fixed the errors found.

## This source code has been transcribed or otherwise adapted from
## digitized images of a hardcopy from the private collection of
## Don Eyles.  The digitization was performed by archive.org.
##
## Notations on the hardcopy document read, in part:
##
##       473423A YUL SYSTEM FOR BLK2: REVISION 12 of PROGRAM AURORA BY DAP GROUP
##       NOV 10, 1966
##
##       [Note that this is the date the hardcopy was made, not the
##       date of the program revision or the assembly.]
##
## The scan images (with suitable reduction in storage size and consequent
## reduction in image quality) are available online at
##       https://www.ibiblio.org/apollo.
## The original high-quality digital images are available at archive.org:
##       https://archive.org/details/aurora00dapg

## Page 425
                SETLOC  ENDINFSS

#          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     SLOAD2 +2       # C(A) = +0.

#          READ IMU CDUS INTO MPAC AS A VECTOR. ESPECIALLY USEFUL IN CONNECTION WITH SMNB, ETC.

READCDUS        INHINT
                CA      CDUY            # IN ORDER Y Z X
                TS      MPAC
                CA      CDUZ
                TS      MPAC +3
                CA      CDUX
                TCF     READPIPS +6     # COMMON CODING.

#          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

## Page 426
VECMODE         CS      ONE
                TCF     NEWMODE

#          FORCE TP SIGN AGREEMENT IN MPAC:

SGNAGREE        TC      TPAGREE
                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

                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 COMVERSION:

1TO2SUB         DXCH    MPAC            # FINAL MPAC +1 UNSPECIFIED.
                DDOUBL
## Page 427
                CCS     A
                AD      ONE
                TCF     +2
                COM                     # THIS WAS REVERSE OF MSU.

                TS      MPAC            # AND SKIP ON OVERFLOW.
                TC      Q

                INDEX   A               # OVERFLOW UNCORRECT AND IN MSU.
                CAF     LIMITS
                ADS     MPAC
                TC      Q

## Page 428
#          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 COMPL. ANGLE(IN BUF)INTO 1S
                AD      ONE
                TCF     +4
                AD      ONE
                AD      ONE             # OVERFLOW HERE IF 2S COMPL. IS 180 DEG.
                COM

                AD      TEM2            # ADD IN INCREMENT. WILL OVERFLOW IF RE-
                                        # 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               # OVERFLOW MEANS CORRECT 14BIT VALUE,WRONG
                                        #  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 429
#          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 430
#          THE FOLLOWING ROUTINE IS USED ONLY IN BENCH TESTING THE RR.

RRSIM           TC      FIXDELAY
                DEC     50

RRSIM2          CAF     BIT2            # SEE IF RR ECTR ENABLED.
                EXTEND
                RAND    12
                EXTEND
                BZF     RRSIM

                CA      TEM2            # SAVE EXEC TEMPS SINCE IN RUPT.
                TS      RUPTREG1
                CAF     LOPTY
                XCH     BUF
                TS      RUPTREG2
                CA      LASTYCMD        # ECTR.
                DOUBLE
                EXTEND
                MP      RRSIMG
                TC      CDUINC
                INCR    BUF
                CA      OPTY            # SHAFT CMD IS DIVIDED BY THE ABS VALUE OF
                EXTEND                  # THE COS OF THE TRUNNION ANGLE.
                MSU     7               # TO 1S COMPLEMENT.
                TC      SPCOS           #                                 *
                EXTEND                  # SPCOS NOW GIVES COS SCALED AT 1 *
                MP      BIT14           #     (A DAP GROUP FIX)           *
                CCS     A
                TCF     +3
                TCF     +2
                TCF     +1
                AD      ONE
                TS      ITEMP1

                CA      LASTXCMD        # SHAFT RATE DEPENDS ON TRUNNION.
                EXTEND
                MP      RRSIMG
                EXTEND
                DV      ITEMP1
                TC      CDUINC
                CA      RUPTREG1
                TS      TEM2
                CA      RUPTREG2
                TS      BUF
                TCF     RRSIM

LOPTY           ADRES   OPTY
RRSIMG          DEC     .59259
ENDRTBSS        EQUALS