https://github.com/virtualagc/virtualagc
Revision 078c79d8734a9ed2860303a7c1662004284fe853 authored by Ron Burkey on 07 August 2022, 15:04:04 UTC, committed by Ron Burkey on 07 August 2022, 15:04:04 UTC
assembly listings from yaASM and yaLEMAP. Added some debugging messages to 'make install'. Tweaked debugging messages that VirtualAGC embeds in 'simulate'. Verified buildability in Mint 21, 20, 19, 17, and verified buildability using clang in Mint 17.
1 parent 6bb1acc
Tip revision: 078c79d8734a9ed2860303a7c1662004284fe853 authored by Ron Burkey on 07 August 2022, 15:04:04 UTC
Fixed a potential string-overflow bug in yaASM. Removed timestamps from
Fixed a potential string-overflow bug in yaASM. Removed timestamps from
Tip revision: 078c79d
ATTITUDE_MANEUVER_ROUTINE.agc
### FILE="Main.annotation"
## Copyright: Public domain.
## Filename: ATTITUDE_MANEUVER_ROUTINE.agc
## Purpose: A section of Luminary revision 173.
## It is part of the reconstructed source code for the second
## (unflown) release of the flight software for the Lunar
## Module's (LM) Apollo Guidance Computer (AGC) for Apollo 14.
## The code has been recreated from a reconstructed copy of
## Luminary 178, as well as Luminary memo 167 (revision 1).
## It has been adapted such that the resulting bugger words
## exactly match those specified for Luminary 173 in NASA
## drawing 2021152N, which gives relatively high confidence
## that the reconstruction is correct.
## Reference: pp. 347-368
## Assembler: yaYUL
## Contact: Ron Burkey <info@sandroid.org>.
## Website: www.ibiblio.org/apollo/index.html
## Mod history: 2019-09-18 MAS Created from Luminary 178.
## Page 347
# BLOCK 2 LGC ATTITUDE MANEUVER ROUTINE-KALCMANU
# MOD 2 DATE 5/1/67 BY DON KEENE
# PROGRAM DESCRIPTION
# KALCMANU IS A ROUTINE WHICH GENERATES COMMANDS FOR THE LM DAP TO CHANGE THE ATTITUDE OF THE SPACECRAFT
# DURING FREE FALL. IT IS DESIGNED TO MANEUVER THE SPACECRAFT FROM ITS INITIAL ORIENTATION TO SOME DESIRED
# ORIENTATION SPECIFIED BY THE PROGRAM WHICH CALLS KALCMANU, AVOIDING GIMBAL LOCK IN THE PROCESS. IN THE
# MOD 2 VERSION, THIS DESIRED ATTITUDE IS SPECIFIED BY A SET OF THREE COMMANDED CDU ANGLES STORED AS 2S COMPLEMENT
# SINGLE PRECISION ANGLES IN THE THREE CONSECUTIVE LOCATIONS, CPHI, CTHETA, CPSI, WHERE
# CPHI = COMMANDED OUTER GIMBAL ANGLE
# CTHETA = COMMANDED INNER GIMBAL ANGLE
# CPSI = COMMANDED MIDDLE GIMBAL ANGLE
# WHEN POINTING A SPACECRAFT AXIS (E.I. X, Y, Z, THE AOT, THRUST AXIS, ETC) THE SUBROUTINE VECPOINT MAY BE
# USED TO GENERATE THIS SET OF DESIRED CDU ANGLES (SEE DESCRIPTION IN R60) -
# WITH THIS INFORMATION KALCMANU DETERMINES THE DIRECTION OF THE SINGLE EQUIVALENT ROTATION (COF ALSO U) AND THE
# MAGNITUDE OF THE ROTATION (AM) TO BRING THE S/C FROM ITS INITIAL ORIENTATION TO ITS FINAL ORIENTATION.
# THIS DIRECTION REMAINS FIXED BOTH IN INERTIAL COORDINATES AND IN COMMANDED S/C AXES THROUGHOUT THE
# -
# MANEUVER. ONCE COF AND AM HAVE BEEN DETERMINED, KALCMANU THEN EXAMINES THE MANEUVER TO SEE IF IT WILL BRING
# -
# THE S/C THROUGH GIMBAL LOCK. IF SO, COF AND AM ARE READJUSTED SO THAT THE S/C WILL JUST SKIM THE GIMBAL
# LOCK ZONE AND ALIGN THE X-AXIS. IN GENERAL A FINAL YAW ABOUT X WILL BE NECESSARY TO COMPLETE THE MANEUVER.
# NEEDLESS TO SAY, NEITHER THE INITIAL NOR THE FINAL ORIENTATION CAN BE IN GIMBAL LOCK.
#
# FOR PROPER ATTITUDE CONTROL THE DIGITAL AUTOPILOT MUST BE GIVEN AN ATTITUDE REFERENCE WHICH IT CAN TRACK.
# KALCMANU DOES THIS BY GENERATING A REFERENCE OF DESIRED GIMBAL ANGLES (CDUXD, CDUYD, CDUZD) WHICH ARE UPDATED
# EVERY ONE SECOND DURING THE MANEUVER. TO ACHIEVE A SMOOTHER SEQUENCE OF COMMANDS BETWEEN SUCCESSIVE UPDATES,
# THE PROGRAM ALSO GENERATES A SET OF INCREMENTAL CDU ANGLES (DELDCDU) TO BE ADDED TO CDU DESIRED BY THE DIGITAL
# AUTOPILOT. KALCMANU ALSO CALCULATES THE COMPONENT MANEUVER RATES (OMEGAPD, OMEGAQD, OMEGARD), WHICH CAN
# -
# BE DETERMINED SIMPLY BY MULTIPLYING COF BY SOME SCALAR (ARATE) CORRESPONDING TO THE DESIRED ROTATIONAL RATE.
#
# AUTOMATIC MANEUVERS ARE TIMED WITH THE HELP OF WAITLIST SO THAT AFTER A SPECIFIED INTERVAL THE Y AND Z
# DESIRED RATES ARE SET TO ZERO AND THE DESIRED CDU ANGLES (CDUYD, CDUZD) ARE SET EQUAL TO THE FINAL DESIRED CDU
# ANGLES (CTHETA, CPSI). IF ANY YAW REMAINS DUE TO GIMBAL LOCK AVOIDANCE, THE FINAL YAW MANEUVER IS
# CALCULATED AND THE DESIRED YAW RATE SET TO SOME FIXED VALUE (ROLLRATE = + OR - 2 DEGREES PER SEC).
# IN THIS CASE ONLY AN INCREMENTAL CDUX ANGLE (DELFROLL) IS SUPPLIED TO THE DAP. AT THE END OF THE YAW
# MANEUVER OR IN THE EVENT THAT THERE WAS NO FINAL YAW, CDUXD IS SET EQUAL TO CPHI AND THE X-AXIS DESIRED
# RATE SET TO ZERO. THUS, UPON COMPLETION OF THE MANEUVER THE S/C WILL FINISH UP IN A LIMIT CYCLE ABOUT THE
# DESIRED FINAL GIMBAL ANGLES.
# PROGRAM LOGIC FLOW
# KALCMANU IS CALLED AS A HIGH PRIORITY JOB WITH ENTRY POINTS AT KALCMAN3 AND VECPOINT. IT FIRST PICKS
# UP THE CURRENT CDU ANGLES TO BE USED AS THE BASIS FOR ALL COMPUTATIONS INVOLVING THE INITIAL S/C ORIENTATION.
## Page 348
# IT THEN DETERMINES THE DIRECTION COSINE MATRICES RELATING BOTH THE INITIAL AND FINAL S/C ORIENTATION TO STABLE
# * * *
# MEMBER AXES (MIS, MFS). IT ALSO COMPUTES THE MATRIX RELATING FINAL S/C AXES TO INITIAL S/C AXES (MFI). THE
# ANGLE OF ROTATION (AM) IS THEN EXTRACTED FROM THIS MATRIX, AND TESTS ARE MADE TO DETERMINE IF
#
# A) AM LESS THAN .25 DEGREES (MINANG)
# B) AM GREATER THAN 170 DEGREES (MAXANG)
# IF AM LESS THAN .25 DEGREES, NO COMPLICATED AUTOMATIC MANEUVERING IS NECESSARY. THEREFORE WE CAN SIMPLY
# SET CDU DESIRED EQUAL TO THE FINAL CDU DESIRED ANGLES AND TERMINATE THE JOB.
#
# IF AM IS GREATER THAN .25 DEGREES BUT LESS THAN 170 DEGREES, THE AXES OF THE SINGLE EQUIVALENT ROTATION
# - *
# (COF) IS EXTRACTED FROM THE SKEW SYMMETRIC COMPONENTS OF MFI. * *
# IF AM GREATER THAN 170 DEGREES AN ALTERNATE METHOD EMPLOYING THE SYMMETRIC PART OF MFI (MFISYM) IS USED
# -
# TO DETERMINE COF.
# THE PROGRAM THEN CHECKS TO SEE IF THE MANEUVER AS COMPUTED WILL BRING THE S/C THROUGH GIMBAL LOCK. IF
# SO, A NEW MANEUVER IS CALCULATED WHICH WILL JUST SKIM THE GIMBAL LOCK ZONE AND ALIGN THE S/C X-AXIS. THIS
# METHOD ASSURES THAT THE ADDITIONAL MANEUVERING TO AVOID GIMBAL LOCK WILL BE KEPT TO A MINIMUM. SINCE A FINAL
# P AXIS YAW WILL BE NECESSARY, A SWITCH IS RESET (STATE SWITCH 31) TO ALLOW FOR THE COMPUTATION OF THIS FINAL
# YAW.
# AS STATED PREVIOUSLY KALCMANU GENERATES A SEQUENCE OF DESIRED GIMBAL ANGLES WHICH ARE UPDATED EVERY
# -
# SECOND. THIS IS ACCOMPLISHED BY A SMALL ROTATION OF THE DESIRED S/C FRAME ABOUT THE VECTOR COF. THE NEW
# DESIRED REFERENCE MATRIX IS THEN,
# * * *
# MIS = MIS DEL
# N+1 N
# *
# WHERE DEL IS THE MATRIX CORRESPONDING TO THIS SMALL ROTATION. THE NEW CDU ANGLES CAN THEN BE EXTRACTED
# *
# FROM MIS.
# AT THE BEGINNING OF THE MANEUVER THE AUTOPILOT DESIRED RATES (OMEGAPD, OMEGAQD, OMEGARD) AND THE
# MANEUVER TIMINGS ARE ESTABLISHED. ON THE FIRST PASS AND ON ALL SUBSEQUENT UPDATES THE CDU DESIRED
# ANGLES ARE LOADED WITH THE APPROPRIATE VALUES AND THE INCREMENTAL CDU ANGLES ARE COMPUTED. THE AGC CLOCKS
# (TIME1 AND TIME2) ARE THAN CHECKED TO SEE IF THE MANEUVER WILL TERMINATE BEFORE THE NEXT UPDATE. IF
# NOT, KALCMANU CALLS FOR ANOTHER UPDATE (RUN AS A JOB WITH PRIORITY TBD) IN ONE SECOND. ANY DELAYS IN THIS
# CALLING SEQUENCE ARE AUTOMATICALLY COMPENSATED IN CALLING FOR THE NEXT UPDATE.
#
# IF IT IS FOUND THAT THE MANEUVER IS TO TERMINATE BEFORE THE NEXT UPDATE A ROUTINE IS CALLED (AS A WAIT-
# LIST TASK) TO STOP THE MANEUVER AT THE APPROPRIATE TIME AS EXPLAINED ABOVE.
## Page 349
# CALLING SEQUENCE
# IN ORDER TO PERFORM A KALCMANU SUPERVISED MANEUVER, THE COMMANDED GIMBAL ANGLES MUST BE PRECOMPUTED AND
# STORED IN LOCATIONS CPHI, CTHETA, CPSI. THE USER:S PROGRAM MUST THEN CLEAR STATE SWITCH NO 33 TO ALLOW THE
# ATTITUDE MANEUVER ROUTINE TO PERFORM ANY FINAL P-AXIS YAW INCURRED BY AVOIDING GIMBAL LOCK. THE MANEUVER IS
# THEN INITIATED BY ESTABLISHING THE FOLLOWING EXECUTIVE JOB
# *
# CAF PRIO XX
# --
# INHINT
# TC FINDVAC
# 2CADR KALCMAN3
# RELINT
# THE USER:S PROGRAM MAY EITHER CONTINUE OR WAIT FOR THE TERMINATION OF THE MANEUVER. IF THE USER WISHES TO
# WAIT, HE MAY PUT HIS JOB TO SLEEP WITH THE FOLLOWING INSTRUCTIONS
# L TC BANKCALL
# L+1 CADR ATTSTALL
# L+2 (BAD RETURN)
# L+3 (GOOD RETURN)
# UPON COMPLETION OF THE MANEUVER, THE PROGRAM WILL BE AWAKENED AT L+3 IF THE MANEUVER WAS COMPLETED
# SUCCESSFULLY, OR AT L+2 IF THE MANEUVER WAS ABORTED. THIS ABORT WOULD OCCUR IF THE INITIAL OR FINAL ATTITUDE
# WAS IN GIMBAL LOCK.
# ***NOTA BENE*** IT IS ASSUMED THAT THE DESIRED MANEUVERING RATE (0.5, 2, 5, 10, DEG/SEC) HAS BEEN SELECTED BY
# KEYBOARD ENTRY PRIOR TO THE EXECUTION OF KALCMANU.
# IT IS ALSO ASSUMED THAT THE AUTOPILOT IS IN THE AUTO MODE. IF THE MODE SWITCH IS CHANGED DURING THE
# MANEUVER, KALCMANU WILL TERMINATE VIA GOODEND WITHIN 1 SECOND SO THAT R60 MAY REQUEST A TRIM OF THE S/C ATTITUDE
# THIS IS THE ONLY MEANS FOR MANUALLY TERMINATING A KALCMANU SUPERVISED MANEUVER.
# SUBROUTINES
# KALCMANU USES A NUMBER OF INTERPRETIVE SUBROUTINES WHICH MAY BE OF GENERAL INTEREST. SINCE THESE ROUTINES
# WERE PROGRAMMED EXCLUSIVELY FOR KALCMANU, THEY ARE NOT, AS YET, GENERALLY AVAILABLE FOR USE BY OTHER PROGRAMS.
#
# MXM3
# ----
# THIS SUBROUTINE MULTIPLIES TWO 3X3 MATRICES AND LEAVES THE RESULT IN THE FIRST 18 LOCATIONS OF THE PUSH
# DOWN LIST, I.E.,
# (M M M )
# ( 0 1 2)
# * ( ) * *
# M = (M M M ) = M1 X M2
# ( 3 4 5)
# ( )
# (M M M )
## Page 350
# ( 6 7 8)
# *
# INDEX REGISTER X1 MUST BE LOADED WITH THE COMPLEMENT OF THE STARTING ADDRESS FOR M1, AND X2 MUST BE
# *
# LOADED WITH THE COMPLEMENT OF THE STARTING ADDRESS FOR M2. THE ROUTINE USES THE FIRST 20 LOCATIONS OF THE PUSH
# DOWN LIST. THE FIRST ELEMENT OF THE MATRIX APPEARS IN PDO. PUSH UP FOR M .
# 8
#
# TRANSPOS
# --------
# THIS ROUTINE TRANSPOSES A 3X3 MATRIX AND LEAVES THE RESULT IN THE PUSH DOWN LIST, I.E.,
#
# * * T
# M = M1
# INDEX REGISTER X1 MUST CONTAIN THE COMPLEMENT OF THE STARTING ADDRESS FOR M1. PUSH UP FOR THE FIRST AND SUB-
# *
# SEQUENT COMPONENTS OF M. THIS SUBROUTINE ALSO USES THE FIRST 20 LOCATIONS OF THE PUSH DOWN LIST.
#
# CDU TO DCM
# ----------
# THIS SUBROUTINE CONVERTS THREE CDU ANGLES IN T(MPAC) TO A DIRECTION COSINE MATRIX (SCALED BY 2) RELATING
# THE CORRESPONDING S/C ORIENTATIONS TO THE STABLE MEMBER FRAME. THE FORMULAS FOR THIS CONVERSION ARE
#
# M = COSY COSZ
# 0
# M = -COSY SINZ COSX + SINY SINX
# 1
# M = COSY SINZ SINX + SINY COSX
# 2
# M = SINZ
# 3
# M = COSZ COSX
# 4
# M = -COSZ SINX
# 5
# M = -SINY COSZ
# 6
#
# M = SINY SINZ COSX + COSY SINX
# 7
## Page 351
# M = -SINY SINZ SINX + COSY COSX
# 8
# WHERE X = OUTER GIMBAL ANGLE
# Y = INNER GIMBAL ANGLE
# Z = MIDDLE GIMBAL ANGLE
# THE INTERPRETATION OF THIS MATRIX IS AS FOLLOWS
# IF A , A , A REPRESENT THE COMPONENTS OF A VECTOR IN S/C AXES THEN THE COMPONENTS OF THE SAME VECTOR IN
# X Y Z
# STABLE MEMBER AXES (B , B , B ) ARE
# X Y Z
# (B ) (A )
# ( X) ( X)
# ( ) ( )
# ( ) * ( )
# (B ) = M (A )
# ( Y) ( Y)
# ( ) ( )
# (B ) (A )
# ( Z) ( Z)
# THE SUBROUTINE WILL STORE THIS MATRIX IN SEQUENTIAL LOCATIONS OF ERASABLE MEMORY AS SPECIFIED BY THE CALLING
# *
# PROGRAM. TO DO THIS THE CALLING PROGRAM MUST FIRST LOAD X2 WITH THE COMPLEMENT OF THE STARTING ADDRESS FOR M.
#
# INTERNALLY, THE ROUTINE USES THE FIRST 16 LOCATIONS OF THE PUSH DOWN LIST, ALSO STEP REGISTER S1 AND INDEX
# REGISTER X2.
# DCM TO CDU
# ----------
# *
# THIS ROUTINE EXTRACTS THE CDU ANGLES FROM A DIRECTION COSINE MATRIX (M SCALED BY 2) RELATING S/C AXIS TO
# *
# STABLE MEMBER AXES. X1 MUST CONTAIN THE COMPLEMENT OF THE STARTING ADDRESS FOR M. THE SUBROUTINE LEAVES THE
# CORRESPONDING GIMBAL ANGLES IN V(MPAC) AS DOUBLE PRECISION 1:S COMPLEMENT ANGLES SCALED BY 2PI. THE FORMULAS
# FOR THIS CONVERSION ARE
# Z = ARCSIN (M )
# 3
# Y = ARCSIN (-M /COSZ)
# 6
# IF M IS NEGATIVE, Y IS REPLACED BY PI SGN Y - Y
# 0
## Page 352
# X = ARCSIN (-M /COSZ)
# 5
# IF M IS NEGATIVE X IS REPLACED BY PI SGN X - X
# 4
# THIS ROUTINE DOES NOT SET THE PUSH DOWN POINTER, BUT USES THE NEXT 8 LOCATIONS OF THE PUSH DOWN LIST AND
# RETURNS THE POINTER TO ITS ORIGINAL SETTING. THIS PROCEDURE ALLOWS THE CALLER TO STORE THE MATRIX AT THE TOP OF
# THE PUSH DOWN LIST.
# DELCOMP
# -------
# *
# THIS ROUTINE COMPUTES THE DIRECTION COSINE MATRIX (DEL) RELATING ON
# -
# IS ROTATED WITH RESPECT TO THE FIRST BY AN ANGLE, A, ABOUT A UNIT VECTOR, U. THE FORMULA FOR THIS MATRIX IS
#
# * * --T *
# DEL = I COSA + UU (1-COSA) + V SINA
# X
# WHERE * (1 0 0)
# I = (0 1 0)
# (0 0 1)
# 2
# (U U U U U )
# ( X X Y X Z)
# ( )
# --T ( 2 )
# UU = (U U U U U )
# ( Y X Y Y Z )
# ( )
# ( 2 )
# (U U U U U )
# ( Z X Z Y Z )
# (0 -U U )
# ( Z Y )
# * ( )
# V = (U 0 -U )
# X ( Z X)
# ( )
# (-U U 0 )
# ( Y X )
## Page 353
# -
# U = UNIT ROTATION VECTOR RESOLVED INTO S/C AXES
# A = ROTATION ANGLE
# *
# THE INTERPRETATION OF DEL IS AS FOLLOWS
# IF A , A , A REPRESENT THE COMPONENT OF A VECTOR INTHE ROTATED FRAME, THEN THE COMPONENTS OF THE SAME
# X Y Z
# VECTOR IN THE ORIGINAL S/C AXES (B , B , B ) ARE
# X Y Z
# (B ) (A )
# ( X) ( X)
# ( ) * ( )
# (B ) = DEL (A )
# ( Y) ( Y)
# ( ) ( )
# (B ) (A )
# ( Z) ( Z)
# THE ROUTINE WILL STORE THIS MATRIX (SCALED UNITY) IN SEQUENTIAL LOCATIONS OF ERASABLE MEMORY BEGINNING WITH
# -
# THE LOCATION CALLED DEL. IN ORDER TO USE THE ROUTINE, THE CALLING PROGRAM MUST FIRST STORE U (A HALF UNIT
# DOUBLE PRECISION VECTOR) IN THE SET OF ERASABLE LOCATIONS BEGINNING WITH THE ADDRESS CALLED COF. THE ANGLE, A,
# MUST THEN BE LOADED INTO D(MPAC).
# INTERNALLY, THE PROGRAM ALSO USES THE FIRST 10 LOCATIONS OF THE PUSH DOWN LIST.
#
# READCDUK
# --------
# THIS BASIC LANGUAGE SUBROUTINE LOADS T(MPAC) WITH THE THREE CDU ANGLES.
# SIGNMPAC
# --------
# THIS IS A BASIC LANGUAGE SUBROUTINE WHICH LIMITS THE MAGNITUDE OF D(MPAC) TO + OR - DPOSMAX ON OVERFLOW.
#
# PROGRAM STORAGE ALLOCATION
# 1) FIXED MEMORY 1059 WORDS
# 2) ERASABLE MEMORY 98
# 3) STATE SWITCHES 3
## Page 354
# 4) FLAGS 1
# JOB PRIORITIES
# 1) KALCMANU TBD
# 2) ONE SECOND UPDATE TBD
# SUMMARY OF STATE SWITCHES AND FLAGWORDS USED BY KALCMANU.
# STATE FLAGWRD 2 SETTING MEANING
# SWITCH NO. BIT NO.
# *
# 31 14 0 MANEUVER WENT THROUGH GIMBAL LOCK
# 1 MANEUVER DID NOT GO THROUGH GIMBAL LOCK
#
# *
# 32 13 0 CONTINUE UPDATE PROCESS
# 1 START UPDATE PROCESS
# 33 12 0 PERFORM FINAL P-AXIS YAW IF REQUIRED
# 1 IGNORE ANY FINAL P-AXIS YAW
#
# 34 11 0 SIGNAL END OF KALCMANU
# 1 KALCMANU IN PROCESS USER MUST SET SWITCH BEFORE INITIATING
# * INTERNAL TO KALCMANU
# SUGGESTIONS FOR PROGRAM INTEGRATION
# THE FOLLOWING VARIABLES SHOULD BE ASSIGNED TO UNSWITCH ERASABLE
# CPHI
# CTHETA
# CPSI
# POINTVSM +5
# SCAXIS +5
# DELDCDU
# DELDCDU1
# DELDCDU2
# RATEINDX
# THE FOLLOWING SUBROUTINES MAY BE PUT IN A DIFFERENT BANK
# MXM3
## Page 355
# TRANSPOS
# SIGNMPAC
# READCDUK
# CDUTODCM
## Page 356
BANK 15
SETLOC KALCMON1
BANK
EBANK= BCDU
# THE THREE DESIRED CDU ANGLES MUST BE STORED AS SINGLE PRECISION TWOS COMPLEMENT ANGLES IN THE THREE SUCCESSIVE
# LOCATIONS, CPHI, CTHETA, CPSI.
COUNT* $$/KALC
KALCMAN3 TC INTPRET # PICK UP THE CURRENT CDU ANGLES AND
RTB # COMPUTE THE MATRIX FROM INITIAL S/C
READCDUK # AXES TO FINAL S/C AXES
STORE BCDU # STORE INITIAL S/C ANGLES
SLOAD ABS # CHECK THE MAGNITUDE OF THE DESIRED
CPSI # MIDDLE GIMBAL ANGLE
DSU BPL
LOCKANGL # IF GREATER THAN 70 DEG ABORT MANEUVER
TOOBADF
AXC,2 TLOAD
MIS
BCDU
CALL # COMPUTE THE TRANSFORMATION FROM INITIAL
CDUTODCM # S/C AXES TO STABLE MEMBER AXES
AXC,2 TLOAD
MFS # PREPARE TO CALCULATE ARRAY MFS
CPHI
CALL
CDUTODCM
SECAD AXC,1 CALL # MIS AND MFS ARRAYS CALCULATED $2
MIS
TRANSPOS
VLOAD STADR
STOVL TMIS +12D
STADR
STOVL TMIS +6
STADR
STORE TMIS # TMIS = TRANSPOSE(MIS) SCALED BY 2
AXC,1 AXC,2
TMIS
MFS
CALL
MXM3
VLOAD STADR
STOVL MFI +12D
STADR
STOVL MFI +6
STADR
STORE MFI # MFI = TMIS MFS (SCALED BY 4)
SETPD CALL # TRANSPOSE MFI IN PD LIST
## Page 357
18D
TRNSPSPD
VLOAD STADR
STOVL TMFI +12D
STADR
STOVL TMFI +6
STADR
STORE TMFI # TMFI = TRANSPOSE (MFI) SCALED BY 4
# CALCULATE COFSKEW AND MFISYM
DLOAD DSU
TMFI +2
MFI +2
PDDL DSU # CALCULATE COF SCALED BY 2/SIN(AM)
MFI +4
TMFI +4
PDDL DSU
TMFI +10D
MFI +10D
VDEF
STORE COFSKEW # EQUALS MFISKEW
# CALCULATE AM AND PROCEED ACCORDING TO ITS MAGNITUDE
DLOAD DAD
MFI
MFI +16D
DSU DAD
DP1/4TH
MFI +8D
STORE CAM # CAM = (MFI0+MFI4+MFI8-1)/2 HALF SCALE
ARCCOS
STORE AM # AM=ARCCOS(CAM) (AM SCALED BY 2)
DSU BPL
MINANG
CHECKMAX
TLOAD # MANEUVER LESS THAN .25 DEGREES
CPHI # GO DIRECTLY INTO ATTITUDE HOLD
STCALL CDUXD # ABOUT COMMANDED ANGLES
TOOBADI # STOP RATE AND EXIT
CHECKMAX DLOAD DSU
AM
MAXANG
BPL VLOAD
ALTCALC # UNIT
COFSKEW # COFSKEW
UNIT
STORE COF # COF IS THE MANEUVER AXIS
## Page 358
GOTO # SEE IF MANEUVER GOES THRU GIMBAL LOCK
LOCSKIRT
ALTCALC VLOAD VAD # IF AM GREATER THAN 170 DEGREES
MFI
TMFI
VSR1
STOVL MFISYM
MFI +6
VAD VSR1
TMFI +6
STOVL MFISYM +6
MFI +12D
VAD VSR1
TMFI +12D
STORE MFISYM +12D # MFISYM=(MFI+TMFI)/2 SCALED BY 4
# CALCULATE COF
DLOAD SR1
CAM
PDDL DSU # PDO CAM $4
DPHALF
CAM
BOVB PDDL # PD2 1 - CAM $2
SIGNMPAC
MFISYM +16D
DSU DDV
0
2
SQRT PDDL # COFZ = SQRT(MFISYM8-CAM)/1-CAM)
MFISYM +8D # $ ROOT 2
DSU DDV
0
2
SQRT PDDL # COFY = SQRT(MFISYM4-CAM)/(1-CAM) $ROOT2
MFISYM
DSU DDV
0
2
SQRT VDEF # COFX = SQRT(MFISYM-CAM)/(1-CAM) $ROOT 2
UNIT
STORE COF
# DETERMINE LARGEST COF AND ADJUST ACCORDINGLY
COFMAXGO DLOAD DSU
COF
COF +2
BMN DLOAD # COFY G COFX
## Page 359
COMP12
COF
DSU BMN
COF +4
METHOD3 # COFZ G COFX OR COFY
GOTO
METHOD1 # COFX G COFY OR COFZ
COMP12 DLOAD DSU
COF +2
COF +4
BMN
METHOD3 # COFZ G COFY OR COFX
METHOD2 DLOAD BPL # COFY MAX
COFSKEW +2 # UY
U2POS
VLOAD VCOMP
COF
STORE COF
U2POS DLOAD BPL
MFISYM +2 # UX UY
OKU21
DLOAD DCOMP # SIGN OF UX OPPOSITE TO UY
COF
STORE COF
OKU21 DLOAD BPL
MFISYM +10D # UY UZ
LOCSKIRT
DLOAD DCOMP # SIGN OF UZ OPPOSITE TO UY
COF +4
STORE COF +4
GOTO
LOCSKIRT
METHOD1 DLOAD BPL # COFX MAX
COFSKEW # UX
U1POS
VLOAD VCOMP
COF
STORE COF
U1POS DLOAD BPL
MFISYM +2 # UX UY
OKU12
DLOAD DCOMP
COF +2 # SIGN OF UY OPPOSITE TO UX
STORE COF +2
OKU12 DLOAD BPL
MFISYM +4 # UX UZ
LOCSKIRT
DLOAD DCOMP # SIGN OF UZ OPPOSITE TO UY
COF +4
## Page 360
STORE COF +4
GOTO
LOCSKIRT
METHOD3 DLOAD BPL # COFZ MAX
COFSKEW +4 # UZ
U3POS
VLOAD VCOMP
COF
STORE COF
U3POS DLOAD BPL
MFISYM +4 # UX UZ
OKU31
DLOAD DCOMP
COF # SIGN OF UX OPPOSITE TO UZ
STORE COF
OKU31 DLOAD BPL
MFISYM +10D # UY UZ
LOCSKIRT
DLOAD DCOMP
COF +2 # SIGN OF UY OPPOSITE TO UZ
STORE COF +2
GOTO
LOCSKIRT
## Page 361
# MATRIX OPERATIONS
BANK 13
SETLOC KALCMON2
BANK
EBANK= BCDU
MXM3 SETPD VLOAD* # MXM3 MULTIPLIES 2 3X3 MATRICES
0 # AND LEAVES RESULT IN PD LIST
0,1 # AND MPAC
VXM* PDVL*
0,2
6,1
VXM* PDVL*
0,2
12D,1
VXM* PUSH
0,2
RVQ
# RETURN WITH M1XM2 IN PD LIST
TRANSPOS SETPD VLOAD* # TRANSPOS TRANSPOSES A 3X3 MATRIX
0 # AND LEAVES RESULT IN PD LIST
0,1 # MATRIX ADDRESS IN XR1
PDVL* PDVL*
6,1
12D,1
PUSH # MATRIX IN PD
TRNSPSPD EXIT # ENTER WITH MATRIX AT 0 IN PD LIST
INDEX FIXLOC
DXCH 12
INDEX FIXLOC
DXCH 16
INDEX FIXLOC
DXCH 12
INDEX FIXLOC
DXCH 14
INDEX FIXLOC
DXCH 4
INDEX FIXLOC
DXCH 14
INDEX FIXLOC
DXCH 2
INDEX FIXLOC
DXCH 6
INDEX FIXLOC
DXCH 2
## Page 362
TC INTPRET
RVQ
BANK 15
SETLOC KALCMON1
BANK
EBANK= BCDU
MINANG 2DEC 0.00069375
MAXANG 2DEC 0.472222222
# GIMBAL LOCK CONSTANTS
# D = MGA CORRESPONDING TO GIMBAL LOCK = 60 DEGREES
# NGL = BUFFER ANGLE (TO AVOID DIVISIONS BY ZERO) = 2 DEGREES
SD 2DEC .433015 # = SIN(D) $2
K3S1 2DEC .86603 # = SIN(D) $1
K4 2DEC -.25 # = -COS(D) $2
K4SQ 2DEC .125 # = COS(D)COS(D) $2
SNGLCD 2DEC .008725 # = SIN(NGL)COS(D) $2
CNGL 2DEC .499695 # COS(NGL) $2
LOCKANGL DEC .388889 # = 70 DEGREES
# INTERPRETIVE SUBROUTINE TO READ THE CDU ANGLES
READCDUK CA CDUZ # LOAD T(MPAC) WITH CDU ANGLES
TS MPAC +2
EXTEND
DCA CDUX # AND CHANGE MODE TO TRIPLE PRECISION
TCF TLOAD +6
CDUTODCM AXT,1 SSP
OCT 3
S1
OCT 1 # SET XR1, S1, AND PD FOR LOOP
STORE 7
SETPD
0
LOOPSIN SLOAD* RTB
10D,1
CDULOGIC
## Page 363
STORE 10D # LOAD PD WITH 0 SIN(PHI)
SIN PDDL # 2 COS(PHI)
10D # 4 SIN(THETA)
COS PUSH # 6 COS(THETA)
TIX,1 DLOAD # 8 SIN(PSI)
LOOPSIN # 10 COS(PSI)
6
DMP SL1
10D
STORE 0,2 # C0=COS(THETA)COS(PSI)
DLOAD DMP
4
0
PDDL DMP # (PD6 SIN(THETA)SIN(PHI))
6
8D
DMP SL1
2
BDSU SL1
12D
STORE 2,2 # C1=-COS(THETA)SIN(PSI)COS(PHI)
DLOAD DMP
2
4
PDDL DMP # (PD7 COS(PHI)SIN(THETA)) SCALED 4
6
8D
DMP SL1
0
DAD SL1
14D
STORE 4,2 # C2=COS(THETA)SIN(PSI)SIN(PHI)
DLOAD
8D
STORE 6,2 # C3=SIN(PSI)
DLOAD
10D
DMP SL1
2
STORE 8D,2 # C4=COS(PSI)COS(PHI)
DLOAD DMP
10D
0
DCOMP SL1
STORE 10D,2 # C5=-COS(PSI)SIN(PHI)
DLOAD DMP
4
10D
DCOMP SL1
STORE 12D,2 # C6=-SIN(THETA)COS(PSI)
## Page 364
DLOAD
DMP SL1 # (PUSH UP 7)
8D
PDDL DMP # (PD7 COS(PHI)SIN(THETA)SIN(PSI)) SCALE4
6
0
DAD SL1 # (PUSH UP 7)
STADR # C7=COS(PHI)SIN(THETA)SIN(PSI)
STORE 14D,2 # +COS(THETA)SIN(PHI)
DLOAD
DMP SL1 # (PUSH UP 6)
8D
PDDL DMP # (PD6 SIN(THETA)SIN(PHI)SIN(PSI)) SCALE4
6
2
DSU SL1 # (PUSH UP 6)
STADR
STORE 16D,2 # C8=-SIN(THETA)SIN(PHI)SIN(PSI)
RVQ # +COS(THETA)COS(PHI)
# CALCULATION OF THE MATRIX DEL......
# * * --T *
# DEL = (IDMATRIX)COS(A)+UU (1-COS(A))+UX SIN(A) SCALED 1
# -
# WHERE U IS A UNIT VECTOR (DP SCALED 2) ALONG THE AXIS OF ROTATION.
# A IS THE ANGLE OF ROTATION (DP SCALED 2)
# -
# UPON ENTRY THE STARTING ADDRESS OF U IS COF, AND A IS IN MPAC
DELCOMP SETPD PUSH # MPAC CONTAINS THE ANGLE A
0
SIN PDDL # PD0 = SIN(A)
COS PUSH # PD2 = COS(A)
SR2 PDDL # PD2 = COS(A) $8
BDSU BOVB
DPHALF
SIGNMPAC
PDDL # PD4 = 1-COS(A)
# COMPUTE THE DIAGONAL COMPONENTS OF DEL
COF
DSQ DMP
4
DAD SL3
2
BOVB
SIGNMPAC
## Page 365
STODL KEL # UX UX(1-COS(A)) +COS(A) $1
COF +2
DSQ DMP
4
DAD SL3
2
BOVB
SIGNMPAC
STODL KEL +8D # UY UY(1-COS(A)) +COS(A) $1
COF +4
DSQ DMP
4
DAD SL3
2
BOVB
SIGNMPAC
STORE KEL +16D # UZ UZ(1-COS(A)) +COS(A) $1
# COMPUTE THE OFF DIAGONAL TERMS OF DEL
DLOAD DMP
COF
COF +2
DMP SL1
4
PDDL DMP # D6 UX UY (1-COS A) $ 4
COF +4
0
PUSH DAD # D8 UZ SIN A $ 4
6
SL2 BOVB
SIGNMPAC
STODL KEL +6
BDSU SL2
BOVB
SIGNMPAC
STODL KEL +2
COF
DMP DMP
COF +4
4
SL1 PDDL # D6 UX UZ (1-COS A) $ 4
COF +2
DMP PUSH # D8 UY SIN(A)
0
DAD SL2
6
BOVB
SIGNMPAC
STODL KEL +4 # UX UZ (1-COS(A))+UY SIN(A)
## Page 366
BDSU SL2
BOVB
SIGNMPAC
STODL KEL +12D # UX UZ (1-COS(A))-UY SIN(A)
COF +2
DMP DMP
COF +4
4
SL1 PDDL # D6 UY UZ (1-COS(A)) $ 4
COF
DMP PUSH # D8 UX SIN(A)
0
DAD SL2
6
BOVB
SIGNMPAC
STODL KEL +14D # UY UZ(1-COS(A)) +UX SIN(A)
BDSU SL2
BOVB
SIGNMPAC
STORE KEL +10D # UY UZ (1-COS(A)) -UX SIN(A)
RVQ
# DIRECTION COSINE MATRIX TO CDU ANGLE ROUTINE
# X1 CONTAINS THE COMPLEMENT OF THE STARTING ADDRESS FOR MATRIX (SCALED 2)
# LEAVES CDU ANGLES SCALED 2PI IN V(MPAC)
# COS(MGA) WILL BE LEFT IN S1 (SCALED 1)
# THE DIRECTION COSINE MATRIX RELATING S/C AXES TO STABLE MEMBER AXES CAN BE WRITTEN AS***
# C =COS(THETA)COS(PSI)
# 0
# C =-COS(THETA)SIN(PSI)COS(PHI)+SI (THETA)SIN(PHI)
# 1
# C =COS(THETA)SIN(PSI)SIN(PHI) + S N(THETA)COS(PHI)
# 2
# C =SIN(PSI)
# 3
# C =COS(PSI)COS(PHI)
# 4
# C =-COS(PSI)SIN(PHI)
# 5
# C =-SIN(THETA)COS(PSI)
# 6
# C =SIN(THETA)SIN(PSI)COS(PHI)+COS THETA)SIN(PHI)
# 7
# C =-SIN(THETA)SIN(PSI)SIN(PHI)+CO (THETA)COS(PHI)
# 8
## Page 367
# WHERE PHI = OGA
# THETA = IGA
# PSI = MGA
DCMTOCDU DLOAD* ARCSIN
6,1
PUSH COS # PD +0 PSI
SL1 BOVB
SIGNMPAC
STORE S1
DLOAD* DCOMP
12D,1
DDV ARCSIN
S1
PDDL* BPL # PD +2 THETA
0,1 # MUST CHECK THE SIGN OF COS(THETA)
OKTHETA # TO DETERMINE THE PROPER QUADRANT
DLOAD DCOMP
BPL DAD
SUHALFA
DPHALF
GOTO
CALCPHI
SUHALFA DSU
DPHALF
CALCPHI PUSH
OKTHETA DLOAD* DCOMP
10D,1
DDV ARCSIN
S1
PDDL* BPL # PUSH DOWN PHI
8D,1
OKPHI
DLOAD DCOMP # PUSH UP PHI
BPL DAD
SUHALFAP
DPHALF
GOTO
VECOFANG
SUHALFAP DSU GOTO
DPHALF
VECOFANG
OKPHI DLOAD # PUSH UP PHI
VECOFANG VDEF RVQ
## Page 368
# ROUTINES FOR TERMINATING THE AUTOMATIC MANEUVER AND RETURNING TO USER
TOOBADF EXIT
TC ALARM
OCT 00401
TCF NOGO # DO NOT ZERO ATTITUDE ERRORS
TC BANKCALL
CADR ZATTEROR # ZERO ATTITUDE ERRORS
NOGO TC BANKCALL
CADR STOPRATE # STOP RATES
CAF TWO
INHINT # ALL RETURNS ARE NOW MADE VIA GOODEND
TC WAITLIST
EBANK= BCDU
2CADR GOODMANU
TCF ENDOFJOB
TOOBADI EXIT
TCF NOGO
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