Apollo-11/Luminary099/LUNAR_LANDING_GUIDANCE_EQUATIONS.agc

# Copyright:	Public domain.
# Filename:	LUNAR_LANDING_GUIDANCE_EQUATIONS.agc
# Purpose: 	Part of the source code for Luminary 1A build 099.
#		It is part of the source code for the Lunar Module's (LM)
#		Apollo Guidance Computer (AGC), for Apollo 11.
# Assembler:	yaYUL
# Contact:	HARTMUTH GUTSCHE <hgutsche@xplornet.com>.
# Website:	www.ibiblio.org/apollo.
# Pages:	798-828
# Mod history:	2009-05-23 HG	Transcribed from page images.
#		2009-06-05 RSB	Fixed a goofy thing that was apparently
#				legal in GAP but not in yaYUL.  Eliminated
#				a couple of lines of code that shouldn't
#				have survived from Luminary 131 to here.
#		2009-06-07 RSB	Fixed a typo.
#
# This source code has been transcribed or otherwise adapted from
# digitized images of a hardcopy from the MIT Museum.  The digitization
# was performed by Paul Fjeld, and arranged for by Deborah Douglas of
# the Museum.  Many thanks to both.  The images (with suitable reduction
# in storage size and consequent reduction in image quality as well) are
# available online at www.ibiblio.org/apollo.  If for some reason you
# find that the images are illegible, contact me at info@sandroid.org
# about getting access to the (much) higher-quality images which Paul
# actually created.
#
# Notations on the hardcopy document read, in part:
#
#	Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
#	16:27 JULY 14, 1969

# Page 798
		EBANK=	E2DPS
		COUNT*	$$/F2DPS

# ********************************************************
# LUNAR LANDING FLIGHT SEQUENCE TABLES
# ********************************************************

# FLIGHT SEQUENCE TABLES ARE ARRANGED BY FUNCTION.  THEY ARE REFERENCED USING AS AN INDEX THE REGISTER WCHPHASE:
#	WCHPHASE = -1 ---> IGNALG
#	WCHPHASE =  0 ---> BRAKQUAD
#	WCHPHASE =  1 ---> APPRQUAD
#	WCHPHASE =  2 ---> VERTICAL

#*********************************************************

# ROUTINES FOR STARTING NEW GUIDANCE PHASES:

		TCF	TTFINCR		# IGNALG
NEWPHASE	TCF	TTFINCR		# BRAKQUAD
		TCF	STARTP64	# APPRQUAD
		TCF	P65START	# VERTICAL

# PRE-GUIDANCE COMPUTATIONS:

		TCF	CALCRGVG	# IGNALG
PREGUIDE	TCF	RGVGCALC	# BRAKQUAD
		TCF	REDESIG		# APPRQUAD
		TCF	RGVGCALC	# VERTICAL

# GUIDANCE EQUATIONS:

		TCF	TTF/8CL		# IGNALG
WHATGUID	TCF	TTF/8CL		# BRAKQUAD
		TCF	TTF/8CL		# APPRQUAD
		TCF	VERTGUID	# VERTICAL

# POST GUIDANCE EQUATION COMPUTATIONS:

		TCF	CGCALC		# IGNALG
AFTRGUID	TCF	CGCALC		# BRAKQUAD
		TCF	CGCALC		# APPRQUAD
		TCF	STEER?		# VERTICAL

# Page 799
# WINDOW VECTOR COMPUTATIONS:

		TCF	EXGSUB		# IGNALG
WHATEXIT	TCF	EXBRAK		# BRAKQUAD
		TCF	EXNORM		# APPRQUAD

# DISPLAY ROUTINES:

WHATDISP	TCF	P63DISPS	# BRAKQUAD
		TCF	P64DISPS	# APPRQUAD
		TCF	VERTDISP	# VERTICAL

# ALARM ROUTINE FOR TTF COMPUTATION:

		TCF	1406P00		# IGNALG
WHATALM		TCF	1406ALM		# BRAKQUAD
		TCF	1406ALM		# APPRQUAD

# INDICES FOR REFERENCING TARGET PARAMETERS

		OCT	0		# IGNALG
TARGTDEX	OCT	0		# BRAKQUAD
		OCT	34		# APPRQUAD

#************************************************************************
# ENTRY POINTS:  ?GUIDSUB FOR THE IGNITION ALGORITHM, LUNLAND FOR SERVOUT
#************************************************************************

# IGNITION ALGORITHM ENTRY:  DELIVERS N PASSES OF QUADRATIC GUIDANCE

?GUIDSUB	EXIT
		CAF	TWO		# N = 3
		TS	NGUIDSUB
		TCF	GUILDRET +2

GUIDSUB		TS	NGUIDSUB	# ON SUCCEEDING PASSES SKIP TTFINCR
		TCF	CALCRGVG

# NORMAL ENTRY:  CONTROL COMES HERE FROM SERVOUT

LUNLAND		TC	PHASCHNG
		OCT	00035		# GROUP 5:  RETAIN ONLY PIPA TASK
		TC	PHASCHNG
		OCT	05023		# GROUP 3:  PROTECT GUIDANCE WITH PRIO 21
		OCT	21000		#	JUST HIGHER THAN SERVICER'S PRIORITY

# Page 800
#*******************************************************************
# GUILDENSTERN:  AUTO-MODES MONITOR (R13)
#*******************************************************************

		COUNT*	$$/R13

# HERE IS THE PHILOSOPHY OF GUILDENSTERN:	ON EVERY APPEARANCE OR DISAPPEARANCE OF THE MANUAL THROTTLE
# DISCRETE TO SELECT P67 OR P66 RESPECTIVELY:   ON EVERY APPEARANCE OF THE ATTITUDE-HOLD DISCRETE TO SELECT P66
# UNLESS THE CURRENT PROGRAM IS P67 IN WHICH CASE THERE IS NO CHANGE

GUILDEN		EXTEND			# IS UN-AUTO-THROTTLE DISCRETE PRESENT?
# STERN					# RSB 2009: Not originally a comment.
 		READ CHAN30
		MASK	BIT5
 		CCS	A
 		TCF	STARTP67	# YES
P67NOW?		TC	CHECKMM		# NO:  ARE WE IN P67 NOW?
		DEC	67
		TCF	STABL?		# NO
STARTP66	TC	FASTCHNG	# YES
		TC	NEWMODEX
DEC66		DEC	66
		EXTEND
		DCA	HDOTDISP	# SET DESIRED ALTITUDE RATE = CURRENT
		DXCH	VDGVERT		# 	ALTITUDE RATE.
STRTP66A	TC	INTPRET
		SLOAD	PUSH
			PBIASZ
		SLOAD	PUSH
			PBIASY
		SLOAD	VDEF
			PBIASX
		VXSC	SET
			BIASFACT
			RODFLAG
		STOVL	VBIAS
			TEMX
		VCOMP
		STOVL	OLDPIPAX
			ZEROVECS
		STODL	DELVROD
			RODSCALE
		STODL	RODSCAL1
			PIPTIME
		STORE	LASTTPIP
		EXIT
		CAF	ZERO
		TS	FCOLD
		TS	FWEIGHT
		TS	FWEIGHT +1
VRTSTART	TS	WCHVERT
# Page 801
		CAF	TWO		# WCHPHASE = 2 ---> VERTICAL: P65,P66,P67
		TS	WCHPHOLD
		TS	WCHPHASE
		TC	BANKCALL	# TEMPORARY, I HOPE HOPE HOPE
		CADR	STOPRATE	# TEMPORARY, I HOPE HOPE HOPE
		TC	DOWNFLAG	# PERMIT X-AXIS OVERRIDE
		ADRES	XOVINFLG
		TC	DOWNFLAG
		ADRES	REDFLAG
		TCF	VERTGUID

STARTP67	TC	NEWMODEX	# NO HARM IN "STARTING" P67 OVER AND OVER
		DEC	67		# SO NO NEED FOR A FASTCHNG AND NO NEED
		CAF	ZERO		# TO SEE IF ALREADY IN P67.
		TS	RODCOUNT
		CAF	TEN
		TCF	VRTSTART

STABL?		CAF	BIT13		# IS UN-ATTITUDE-HOLD DISCRETE PRESENT?
		EXTEND
		RAND	CHAN31
		CCS	A
		TCF	GUILDRET	# YES ALL'S WELL

P66NOW?		CS	MODREG
		AD	DEC66
		EXTEND
		BZF	RESTART?

		CA	RODCOUNT	# NO. HAS THE ROD SWITCH BEEN "CLICKED"?
		EXTEND
		BZF	GUILDRET	# NO. CONTINUE WITH AUTOMATIC LANDING
		TCF	STARTP66	# YES. SWITCH INTO THE ROD MODE.

RESTART?	CA	FLAGWRD1	# HAS THERE BEEN A RESTART?
		MASK	RODFLBIT
		EXTEND
		BZF	STRTP66A	# YES.  REINITIALIZE BUT LEAVE VDGVERT AS
					#	IS.

		TCF	VERTGUID	# NO: CONTINUE WITH R.O.D.

# *******************************************************************************
# INITIALIZATION FOR THIS PASS
# *******************************************************************************

		COUNT*	$$/F2DPS

GUILDRET	CAF	ZERO
		TS	RODCOUNT

# Page 802
 +2		EXTEND
 		DCA	TPIP
		DXCH	TPIPOLD

		TC	FASTCHNG

		EXTEND
		DCA	PIPTIME1
		DXCH	TPIP

		EXTEND
		DCA	TTF/8
		DXCH	TTF/8TMP

		CCS	FLPASS0
		TCF	TTFINCR

BRSPOT1		INDEX	WCHPHASE
		TCF	NEWPHASE

# ******************************************************************
# ROUTINES TO START NEW PHASES
# ******************************************************************

P65START	TC	NEWMODEX
		DEC	65
		CS	TWO
		TS	WCHVERT
		TC	DOWNFLAG	# PERMIT X-AXIS OVERRIDE
		ADRES	XOVINFLG
		TCF	TTFINCR

STARTP64	TC	NEWMODEX
		DEC	64
		CA	DELTTFAP	# AUGMENT TTF/8
		ADS	TTF/8TMP
		CA	BIT12		# ENABLE RUPT10
		EXTEND
		WOR	CHAN13
		TC	DOWNFLAG	# INITIALIZE REDESIGNATION FLAG
		ADRES	REDFLAG


#		(CONTINUE TO TTFINCR)

# *********************************************************************************
# INCREMENT TTF/8, UPDATE LAND FOR LUNAR ROTATION, DO OTHER USEFUL THINGS
# *********************************************************************************
#
#	TTFINCR COMPUTATIONS ARE AS FOLLOWS --
# Page 803
#		TTF/8 UPDATED FOR TIME SINCE LAST PASS:
#			TTF/8 = TTF/8 + (TPIP - TPIPOLD)/8
#		LANDING SITE VECTOR UPDATED FOR LUNAR ROTATION:
#			____               ____   ____                   __
#			LAND = /LAND/ UNIT(LAND - LAND(TPIP - TPIPOLD) * WM)
#		SLANT RANGE TO LANDING SITE, FOR DISPLAY:
#			                 ____   _
#			RANGEDSP = ABVAL(LAND - R)

TTFINCR		TC	INTPRET
		DLOAD	DSU
			TPIP
			TPIPOLD
		SLR	PUSH		# SHIFT SCALES DELTA TIME TO 2(17) CSECS
			11D
		VXSC	VXV
			LAND
			WM
		BVSU	RTB
			LAND
			NORMUNIT
		VXSC	VSL1
			/LAND/
		STODL	LANDTEMP
		EXIT

		DXCH	MPAC
		DAS	TTF/8TMP	# NOW HAVE INCREMENTED TTF/8 IN TTF/8TMP

		TC	FASTCHNG

		EXTEND
		DCA	TTF/8TMP
		DXCH	TTF/8

		EXTEND
		DCA	LANDTEMP
		DXCH	LAND
		EXTEND
		DCA	LANDTEMP +2
		DXCH	LAND     +2
		EXTEND
		DCA	LANDTEMP +4
		DXCH	LAND	 +4

# Page 804
		TC	TDISPSET
		TC	FASTCHNG	# SINCE REDESIG MAY CHANGE LANDTEMP

BRSPOT2		INDEX	WCHPHASE
		TCF	PREGUIDE

# *********************************************************************
# LANDING SITE PERTURBATION EQUATIONS
# *********************************************************************

REDESIG		CA	FLAGWRD6	# IS REDFLAG SET?
		MASK	REDFLBIT
		EXTEND
		BZF	RGVGCALC	# NO:  SKIP REDESIGNATION LOGIC

		CA	TREDES		# YES:  HAS TREDES REACHED ZERO?
		EXTEND
		BZF	RGVGCALC	# YES:  SKIP REDESIGNATION LOGIC

		INHINT
		CA	ELINCR1
		TS	ELINCR
		CA	AZINCR1
		TS	AZINCR
		TC	FASTCHNG

		CA	ZERO
		TS	ELINCR1
		TS	AZINCR1
		TS	ELINCR	+1
		TS	AZINCR  +1

		CA	FIXLOC		# SET PD TO 0
		TS	PUSHLOC

		TC	INTPRET
		VLOAD	VSU
			LAND
			R		#                 ____   _
		RTB	PUSH		# PUSH DOWN UNIT (LAND - R)
			NORMUNIT
		VXV	VSL1
			YNBPIP		#                    ___        ____   _
		VXSC	PDDL		# PUSH DOWN - ELINCR(YNB * UNIT(LAND - R))
			ELINCR
			AZINCR
		VXSC	VSU
			YNBPIP
		VAD	PUSH		# RESULTING VECTOR IS 1/2 REAL SIZE

# Page 805

		DLOAD	DSU		# MAKE SURE REDESIGNATION IS NOT
			0		# 	TOO CLOSE TO THE HORIZON.
			DEPRCRIT
		BMN	DLOAD
			REDES1
			DEPRCRIT
		STORE	0
REDES1		DLOAD	DSU
			LAND
			R
		DDV	VXSC
			0
		VAD	UNIT
			R
		VXSC	VSL1
			/LAND/
		STORE	LANDTEMP
		EXIT			# LOOKANGL WILL BE COMPUTED AT RGVGCALC

		TC	FASTCHNG

		EXTEND
		DCA	LANDTEMP
		DXCH	LAND
		EXTEND
		DCA	LANDTEMP +2
		DXCH	LAND +2
		EXTEND
		DCA	LANDTEMP +4
		DXCH	LAND +4

		TCF	RGVGCALC

# *********************************************************************
# COMPUTE STATE IN GUIDANCE COORDINATES
# *********************************************************************
#
#	RGVGCALC COMPUTATIONS ARE AS FOLLOWS:--
#	VELOCITY RELATIVE TO THE SURFACE:
#		_______   _   _   __
#		ANGTERM = V + R * WM
#	STATE IN GUIDANCE COORDINATES:
#		___   *   _   ____
#		RGU = CG (R - LAND)
#		___   *   _   __   _
#		VGU = CG (V - WM * R)
# Page 806 actually starts one line earlier but that would separate the markers from their variables
#
#	HORIZONTAL VELOCITY FOR DISPLAY
#
#		VHORIZ = 8 ABVAL (0, VG , VG )
#		                       2    1
# 	DEPRESSION ANGLE FOR DISPLAY:
#		                       _   ____  ______
#		LOOKANGL = ARCSIN(UNIT(R - LAND).XMBPIP)

CALCRGVG	TC	INTPRET		# IN IGNALG, COMPUTE V FROM INTEGRATION
		VLOAD	MXV		#	OUTPUT AND TRIM CORRECTION TERM
			VATT1		#	COMPUTED LAST PASS AND LEFT IN UNFC/2
			REFSMMAT
		VSR1	VAD
			UNFC/2
		STORE	V
		EXIT

RGVGCALC	TC	INTPRET		# ENTER HERE TO RECOMPUTE RG AND VG
		VLOAD	VXV
			R
			WM
		VAD	VSR2		# RESCALE TO UNITS OF 2(9) M/CS
			V
		STORE	ANGTERM
		MXV
			CG		# NO SHIFT SINCE ANGTERM IS DOUBLE SIZED
		STORE	VGU
		PDDL	VDEF		# FORM (0,VG ,VG ) IN UNITS OF 2(10) M/CS
			ZEROVECS	#           2   1
		ABVAL	SL3
		STOVL	VHORIZ		# VHORIZ FOR DISPLAY DURING P65.
			R		#           _   ____
		VSU	PUSH		# PUSH DOWN R - LAND
			LAND
		MXV	VSL1
			CG
		STORE	RGU
		ABVAL
		STOVL	RANGEDSP
		RTB	DOT		# NOW IN MPAC IS SINE(LOOKANGL)/4
			NORMUNIT
			XNBPIP
		EXIT

		CA	FIXLOC		# RESET PUSH DOWN POINTER
		TS	PUSHLOC

# Page 807
		CA	MPAC		# COMPUTE LOOKANGLE ITSELF
		DOUBLE
		TC	BANKCALL
		CADR	SPARCSIN -1
		AD	1/2DEG
		EXTEND
		MP	180DEGS
		TS	LOOKANGL	# LOOKANGL FOR DISPLAY DURING P64

BRSPOT3		INDEX	WCHPHASE
		TCF	WHATGUID

# **************************************************************************
# TTF/8 COMPUTATION
# **************************************************************************

TTF/8CL		TC	INTPRETX
		DLOAD*
			JDG2TTF,1
		STODL*	TABLTTF +6	# A(3) = 8 JDG  TO TABLTTF
			ADG2TTF,1	#             2
		STODL	TABLTTF +4	# A(2) = 6 ADG  TO TABLTTF
			VGU 	+4	#             2
		DMP	DAD*
			3/4DP
			VDG2TTF,1
		STODL*	TABLTTF +2	# A(1) = (6 VGU  + 18 VDG )/8 TO TABLTTF
			RDG +4,1	#              2         2
		DSU	DMP
			RGU +4
			3/8DP
		STORE	TABLTTF		# A(0) = -24 (RGU  - RDG )/64 TO TABLTTF
		EXIT			#                2      2

		CA	BIT8
		TS	TABLTTF +10	# FRACTIONAL PRECISION FOR TTF TO TABLE

		EXTEND
		DCA	TTF/8
		DXCH	MPAC		# LOADS TTF/8 (INITIAL GUESS) INTO MPAC
		CAF	TWO		# DEGREE - ONE
		TS	L
		CAF	TABLTTFL
		TC	ROOTPSRS	# YIELDS TTF/8 IN MPAC
		INDEX	WCHPHASE
		TCF	WHATALM

		EXTEND			# GOOD RETURN
		DCA	MPAC		# FETCH TTF/8 KEEPING IT IN MPAC
		DXCH	TTF/8		# CORRECTED TTF/8

# Page 808
		TC	TDISPSET

# 		(CONTINUE TO QUADGUID)

# *********************************************************************************
# MAIN GUIDANCE EQUATION
# *********************************************************************************
#
#	AS PUBLISHED --
#		              ___   __       ___   __
#		___   ___   6(VDG + VG)   12(RDG - RG)
#		ACG = ADG + ----------- + ------------
#		                TTF        (TTF)(TTF)
#	AS HERE PROGRAMMED --
#		             ___   __
#		      3 (1/4(RDG - RG)   ___   __)
#		      - (------------- + VDG + VG)
#		___   4 (    TTF/8               )   ___
#		ACG = ---------------------------- + ADG
#		                  TTF/8

QUADGUID	CS	TTF/8
		AD	LEADTIME	# LEADTIME IS A NEGATIVE NUMBER
		AD	POSMAX		# SAFEGUARD THE COMPUTATIONS THAT FOLLOW
		TS	L		#	BY FORCING -TTF*LEADTIME > OR = ZERO
		CS	L
		AD	L
		ZL
		EXTEND
		DV	TTF/8
		TS	BUF		# - RATIO OF LAG-DIMINISHED TTF TO TTF
		EXTEND
		SQUARE
		TS	BUF +1
		AD	BUF
		XCH	BUF +1		# RATIO SQUARED - RATIO
		AD	BUF +1
		TS	MPAC		# COEFFICIENT FOR VGU TERM
		AD	BUF +1
		INDEX	FIXLOC
		TS	26D		# COEFFICIENT FOR RDG-RGU TERM
		AD	BUF +1
		INDEX	FIXLOC
		TS	28D		# COEFFICIENT FOR VDG TERM
		AD	BUF
		AD	POSMAX
# Page 809
		AD	BUF +1
		AD	BUF +1
		INDEX	FIXLOC
		TS	30D		# COEFFICIENT FOR ADG TERM

		CAF	ZERO
		TS	MODE

		TC	INTPRETX
		VXSC	PDDL
			VGU
			28D
		VXSC*	PDVL*
			VDG,1
			RDG,1
		VSU	V/SC
			RGU
			TTF/8
		VSR2	VXSC
			26D
		VAD	VAD
		V/SC	VXSC
			TTF/8
			3/4DP
		PDDL	VXSC*
			30D
			ADG,1
		VAD
AFCCALC1	VXM	VSL1		# VERGUID COMES HERE
			CG
		PDVL	V/SC
			GDT/2
			GSCALE
		BVSU	STADR
		STORE	UNFC/2		# UNFC/2 NEED NOT BE UNITIZED
		ABVAL
AFCCALC2	STODL	/AFC/		# MAGNITUDE OF AFC FOR THROTTLE
			UNFC/2		# VERTICAL COMPONENT
		DSQ	PDDL
			UNFC/2 +2	# OUT-OF-PLANE
		DSQ	PDDL
			HIGHESTF
		DDV	DSQ
			MASS		#                        2    2    2
		DSU	DSU		# AMAXHORIZ = SQRT(ATOTAL - A  - A  )
		BPL	DLOAD		#                            1    0
			AFCCALC3
			ZEROVECS
AFCCALC3	SQRT	DAD
			UNFC/2 +4
# Page 810
		BPL	BDSU
			AFCCLEND
			UNFC/2 +4
		STORE	UNFC/2 +4
AFCCLEND	EXIT
		TC	FASTCHNG

		CA	WCHPHASE	# PREPARE FOR PHASE SWITCHING LOGIC
		TS	WCHPHOLD
		INCR	FLPASS0		# INCREMENT PASS COUNTER

BRSPOT4		INDEX	WCHPHASE
		TCF	AFTRGUID

# ***********************************************************************
# ERECT GUIDANCE-STABLE MEMBER TRANSFORMATION MATRIX
# ***********************************************************************

CGCALC		CAF	EBANK5
		TS	EBANK
		EBANK=	TCGIBRAK
		EXTEND
		INDEX	WCHPHASE
		INDEX	TARGTDEX
		DCA	TCGFBRAK
		INCR	BBANK
		INCR	BBANK
		EBANK=	TTF/8
		AD	TTF/8
		XCH	L
		AD	TTF/8
		CCS	A
		CCS	L
		TCF	EXTLOGIC
		TCF	EXTLOGIC
		NOOP

		TC	INTPRETX
		VLOAD	UNIT
			LAND
		STODL	CG
			TTF/8
		DMP*	VXSC
			GAINBRAK,1	# NUMERO MYSTERIOSO
			ANGTERM
		VAD
			LAND
		VSU	RTB
			R
			NORMUNIT
# Page 811
		VXV	RTB
			LAND
			NORMUNIT
		STOVL	CG +6		# SECOND ROW
			CG
		VXV	VSL1
			CG +6
		STORE	CG +14
		EXIT

#		(CONTINUE TO EXTLOGIC)
#
# ***********************************************************************
# PREPARE TO EXIT
# ***********************************************************************
#
# DECIDE (1) HOW TO EXIT, AND (2) WHETHER TO SWITCH PHASES
#
EXTLOGIC	INDEX	WCHPHASE	# WCHPHASE = 1   APPRQUAD
		CA	TENDBRAK	# WCHPHASE = 0   BRAKQUAD
		AD	TTF/8

EXSPOT1		EXTEND
		INDEX	WCHPHASE
		BZMF	WHATEXIT

		TC	FASTCHNG

		CA	WCHPHOLD
		AD	ONE
		TS	WCHPHASE
		CA	ZERO
		TS	FLPASS0		# RESET FLPASS0

		INDEX	WCHPHOLD
		TCF	WHATEXIT

# ***********************************************************************
# ROUTINES FOR EXITING FROM LANDING GUIDANCE
# ***********************************************************************
#
# 1.	EXGSUB IS THE RETURN WHEN GUIDSUB IS CALLED BY THE IGNITION ALGORITHM.
# 2.	EXBRAK IN THE EXIT USED DURING THE BRAKING PHASE.  IN THIS CASE UNIT(R) IS THE WINDOW POINTING VECTOR.
# 3.	EXNORM IS THE EXIT USED AT OTHER TIMES DURING THE BURN.
# (EXOVFLOW IS A SUBROUTINE OF EXBRAK AND EXNORM CALLED WHEN OVERFLOW OCCURRED ANYWHERE IN GUIDANCE.)

EXGSUB		TC	INTPRET		# COMPUTE TRIM VELOCITY CORRECTION TERM.
# Page 812
		VLOAD	RTB
			UNFC/2
			NORMUNIT
		VXSC	VXSC
			ZOOMTIME
			TRIMACCL
		STORE	UNFC/2
		EXIT

		CCS	NGUIDSUB
		TCF	GUIDSUB
		CCS	NIGNLOOP
		TCF	+3
		TC	ALARM
		OCT	01412

 +3		TC	POSTJUMP
 		CADR	DDUMCALC

EXBRAK		TC	INTPRET
		VLOAD
			UNIT/R/
		STORE	UNWC/2
		EXIT
		TCF	STEER?

EXNORM		TC	INTPRET
		VLOAD	VSU
			LAND
			R
		RTB
			NORMUNIT
		STORE	UNWC/2		# UNIT(LAND - R) IS TENTATIVE CHOICE
		VXV	DOT
			XNBPIP
			CG +6
		EXIT			# WITH PROJ IN MPAC 1/8 REAL SIZE

		CS	MPAC		# GET COEFFICIENT FOR CG +14
		AD	PROJMAX
		AD	POSMAX
		TS	BUF
		CS	BUF
		ADS	BUF		# RESULT IS 0 IF PROJMAX - PROJ NEGATIVE

		CS	PROJMIN		# GET COEFFICIENT FOR UNIT(LAND - R)
		AD	MPAC
		AD	POSMAX
		TS	BUF +1
		CS	BUF +1
# Page 813
		ADS	BUF +1		# RESULT IS 0 IF PROJ - PROJMIN NEGATIVE

		CAF	FOUR
UNWCLOOP	MASK	SIX
		TS	Q
		CA	EBANK5
		TS	EBANK
		EBANK=	CG
		CA	BUF
		EXTEND
		INDEX	Q
		MP	CG +14
		INCR	BBANK
		EBANK=	UNWC/2
		INDEX	Q
		DXCH	UNWC/2
		EXTEND
		MP	BUF +1
		INDEX	Q
		DAS	UNWC/2
		CCS	Q
		TCF	UNWCLOOP

		INCR	BBANK
		EBANK=	PIF

STEER?		CA	FLAGWRD2	# IF STEERSW DOWN NO OUTPUTS
		MASK	STEERBIT
		EXTEND
		BZF	RATESTOP

EXVERT		CA	OVFIND		# IF OVERFLOW ANYWHERE IN GUIDANCE
		EXTEND			#	DON'T CALL THROTTLE OR FINDCDUW
		BZF	+13

EXOVFLOW	TC	ALARM		# SOUND THE ALARM NON-ABORTIVELY
		OCT	01410

RATESTOP	CAF	BIT13		# ARE WE IN ATTITUDE-HOLD?
		EXTEND
		RAND	CHAN31
		EXTEND
		BZF	DISPEXIT	# YES

		TC	BANKCALL	# NO:  DO A STOPRATE
		CADR	STOPRATE

		TCF	DISPEXIT

GDUMP1		TC	THROTTLE
# Page 814
		TC	INTPRET
		CALL
			FINDCDUW -2
		EXIT

# 		(CONTINUE TO DISPEXIT)

# ***********************************************************************
# GUIDANCE LOOP DISPLAYS
# ***********************************************************************

DISPEXIT	EXTEND			# KILL GROUP 3:  DISPLAYS WILL BE
		DCA	NEG0		#	RESTORED BY NEXT GUIDANCE CYCLE.
		DXCH	-PHASE3

 +3		CS	FLAGWRD8	# IF FLUNDISP IS SET, NO DISPLAY THIS PASS
 		MASK	FLUNDBIT
		EXTEND
		BZF	ENDLLJOB	# TO PICK UP THE TAG

		INDEX	WCHPHOLD
		TCF	WHATDISP

-2		TC	PHASCHNG	# KILL GROUP 5
		OCT	00035

P63DISPS	CAF	V06N63
DISPCOMN	TC	BANKCALL
		CADR	REGODSPR

ENDLLJOB	TCF	ENDOFJOB

P64DISPS	CA	TREDES		# HAS TREDES REACHED ZERO?
		EXTEND
		BZF	RED-OVER	# YES: CLEAR REDESIGNATION FLAG

		CS	FLAGWRD6	# NO:  IS REDFLAG SET?
		MASK	REDFLBIT
		EXTEND
		BZF	REDES-OK	# YES:  DO STATIC DISPLAY

		CAF	V06N64		# OTHERWISE USE FLASHING DISPLAY
		TC	BANKCALL
		CADR	REFLASHR
		TCF	GOTOP00H	# TERMINATE
		TCF	P64CEED		# PROCEED	PERMIT REDESIGNATIONS
		TCF	P64DISPS	# RECYCLE
# Page 815
		TCF	ENDLLJOB

P64CEED		CAF	ZERO
		TS	ELINCR1
		TS	AZINCR1

		TC	UPFLAG		# ENABLE REDESIGNATION LOGIC
		ADRES	REDFLAG

		TCF	ENDOFJOB

RED-OVER	TC	DOWNFLAG
		ADRES	REDFLAG
REDES-OK	CAF	V06N64
		TCF	DISPCOMN


VERTDISP	CAF	V06N60
		TCF	DISPCOMN


# **************************************************************************
# GUIDANCE FOR P65
# **************************************************************************

VERTGUID	CCS	WCHVERT
		TCF	P67VERT		# POSITIVE NON-ZERO ---> P67
		TCF	P66VERT		# +0
#
# 	THE P65 GUIDANCE EQUATION IS AS FOLLOWS --
#		      ____   ___
#		      V2FG - VGU
#		ACG = ----------
#		        TAUVERT

P65VERT		TC	INTPRET
		VLOAD	VSU
			V2FG
			VGU
		V/SC	GOTO
			TAUVERT
			AFCCALC1
# Page 816
# **********************************************************
# GUIDANCE FOR P66
# **********************************************************

P66VERT		TC	POSTJUMP
		CADR	P66VERTA

P67VERT		TC	PHASCHNG	# TERMINATE GROUP 3.
		OCT	00003

		TC	INTPRET
		VLOAD	GOTO
			V
			VHORCOMP

		SETLOC	P66LOC
		BANK
		COUNT*	$$/F2DPS

RODTASK		CAF	PRIO22
		TC	FINDVAC
		EBANK=	DVCNTR
		2CADR	RODCOMP

		TCF	TASKOVER

P66VERTA	TC	PHASCHNG	# TERMINATE GROUP 3.
		OCT	00003

		CAF	1SEC
		TC	TWIDDLE
		ADRES	RODTASK

RODCOMP		INHINT
		CAF	ZERO
		XCH	RODCOUNT
		EXTEND
		MP	RODSCAL1
		DAS	VDGVERT		# UPDATE DESIRED ALTITUDE RATE.

		EXTEND			# SET OLDPIPAX,Y,Z = PIPAX,Y,Z
		DCA	PIPAX
		DXCH	OLDPIPAX
		DXCH	RUPTREG1	# SET RUPTREG1,2,3 = OLDPIPAX,Y,Z
		CA	PIPAZ
		XCH	OLDPIPAZ
		XCH	RUPTREG3

		EXTEND			# SNAPSHOT TIME OF PIPA READING.
		DCA	TIME2
# Page 817
		DXCH	THISTPIP

		CA	OLDPIPAX
		AD	PIPATMPX
		TS	MPAC		# MPAC(X) = PIPAX + PIPATMPX
		CA	OLDPIPAY
		AD	PIPATMPY
		TS	MPAC +3		# MPAC(Y) = PIPAY + PIPATMPY
		CA	OLDPIPAZ
		AD	PIPATMPZ
		TS	MPAC +5		# MPAC(Z) = PIPAZ + PIPATMPZ

		CS	OLDPIPAX
		AD	TEMX
		AD	RUPTREG1
		TS	DELVROD
		CS	OLDPIPAY
		AD	TEMY
		AD	RUPTREG2
		TS	DELVROD +2
		CS	OLDPIPAZ
		AD	TEMZ
		AD	RUPTREG3
		TS	DELVROD +4

		CAF	ZERO
		TS	MPAC +1		# ZERO LO-ORDER MPAC COMPONENTS
		TS	MPAC +4
		TS	MPAC +6
		TS	TEMX		# ZERO TEMX, TEMY, AND TEMZ SO WE WILL
		TS	TEMY		#	KNOW WHEN READACCS CHANGES THEM.
		TS	TEMZ
		CS	ONE
		TS	MODE
		TC	INTPRET
ITRPNT1		VXSC	PDDL		# SCALE MPAC TO M/CS *2(-7) AND PUSH 	(6)
			KPIP1
			THISTPIP
		DSU
			PIPTIME
		STORE	30D		# 30-31D CONTAINS TIME IN CS SINCE PIPTIME
		DDV	PDVL		#					(8)
			4SEC(28)
			GDT/2
		VSU	VXSC		#					(6)
			VBIAS
		VSL2	VAD
			V
		VAD	STADR		#					(0)
		STOVL	24D		# STORE UPDATED VELOCITY IN 24-29D
# Page 818
			R
		UNIT
		STORE	14D
		DOT	SL1
			24D
		STODL	HDOTDISP	# UPDATE HDOTDISP RATE FOR NOUN 63.
			30D
		SL	DMP
			11D
			HDOTDISP
		DAD	DSU
			36D
			/LAND/
		STODL	HCALC1		# UPDATE HCALC1 FOR NOUN 63.
			HDOTDISP
		BDSU	DDV
			VDGVERT
			TAUROD
		PDVL	ABVAL		#				(2)
			GDT/2
		DDV	SR2
			GSCALE
		STORE	20D
		DAD			#				(0)
		PDVL	CALL		#				(2)
			UNITX
			CDU*NBSM
		DOT
			14D
		STORE	22D
		BDDV	STADR		#				(0)
		STOVL	/AFC/
			DELVROD
		VXSC	VAD
			KPIP1
			VBIAS
		ABVAL	PDDL		#				(2)
			THISTPIP
		DSU	PDDL		#				(4)
			LASTTPIP
			THISTPIP
		STODL	LASTTPIP	#				(2)
		DDV	BDDV		#				(0)
			SHFTFACT
		PDDL	DMP		#				(2)
			FWEIGHT
			BIT1H
		DDV	DDV
			MASS
			SCALEFAC
# Page 819
		DAD	PDDL		#				(4)
			0D
			20D
		DDV	DSU		#				(2)
			22D
		DMP	DAD
			LAG/TAU
			/AFC/
		PDDL	DDV		#				(4)
			MAXFORCE
			MASS
		PDDL	DDV		#				(6)
			MINFORCE
			MASS
		PUSH	BDSU		#				(8)
			2D
		BMN	DLOAD		#				(6)
			AFCSPOT
		DLOAD	PUSH		#				(6)
		BDSU	BPL
			2D
			AFCSPOT
		DLOAD			#				(4)
AFCSPOT		DLOAD			#				(2), (4), OR (6)
		SETPD			#				(2)
			2D
		STODL	/AFC/		#				(0)
ITRPNT2		EXIT
		DXCH	MPAC		# MPAC = MEASURED ACCELERATION.
		TC	BANKCALL
		CADR	THROTTLE +3
		TC	INTPRET
		VLOAD			# PICK UP UPDATED VELOCITY VECTOR.
			24D
VHORCOMP	VSL2	VAD
			DELVS
		VSR2	PDVL
			R
		UNIT	VXSC
			HDOTDISP
		VSL1	BVSU
		ABVAL
		STORE	VHORIZ
		EXIT
		TC	BANKCALL	# PUT UP V06N60 DISPLAY BUT AVOID PHASCHNG
		CADR	DISPEXIT +3

BIT1H		OCT	00001
SHFTFACT	2DEC	1 B-17
# Page 820
BIASFACT	2DEC	655.36 B-28

# *********************************************************************************
# REDESIGNATOR TRAP
# *********************************************************************************

		BANK	11
		SETLOC	F2DPS*11
		BANK

		COUNT*	$$/F2DPS

PITFALL		XCH	BANKRUPT
		EXTEND
		QXCH	QRUPT

		TC	CHECKMM		# IF NOT IN P64, NO REASON TO CONTINUE
		DEC	64
		TCF	RESUME

		EXTEND
		READ	CHAN31
		COM
		MASK	ALL4BITS
		TS	ELVIRA
		CAF	TWO
		TS	ZERLINA
		CAF	FIVE
		TC	TWIDDLE
		ADRES	REDESMON
		TCF	RESUME

# REDESIGNATOR MONITOR (INITIATED BY PITFALL)

PREMON1		TS	ZERLINA
PREMON2		CAF	SEVEN
		TC	VARDELAY
REDESMON	EXTEND
		READ	31
		COM
		MASK	ALL4BITS
		XCH	ELVIRA
		TS	L
		CCS	ELVIRA		# DO ANY BITS APPEAR THIS PASS?
		TCF	PREMON2		# Y:	CONTINUE MONITOR

		CCS	L		# N:	ANY LAST PASS?
		TCF	COUNT'EM	#	Y: 	COUNT 'EM, RESET RUPT, TERMINATE
# Page 821
		CCS	ZERLINA		#	N: 	HAS ZERLINA REACHED ZERO YET?
		TCF	PREMON1		#		N:	DIMINISH ZERLINA, CONTINUE
RESETRPT	CAF	BIT12		#		Y:	RESET RUPT. TERMINATE
		EXTEND
		WOR	CHAN13
		TCF	TASKOVER

COUNT'EM	CAF	BIT13		# ARE WE IN ATTITUDE-HOLD?
		EXTEND
		RAND	CHAN31
		EXTEND
		BZF	RESETRPT	# YES: SKIP REDESIGNATION LOGIC.

		CA	L		# NO.
		MASK 	-AZBIT
		CCS	A
-AZ		CS	AZEACH
		ADS	AZINCR1
		CA	L
		MASK	+AZBIT
		CCS	A
+AZ		CA	AZEACH
		ADS	AZINCR1
		CA	L
		MASK	-ELBIT
		CCS	A
-EL		CS	ELEACH
		ADS	ELINCR1
		CA	L
		MASK	+ELBIT
		CCS	A
+EL		CA	ELEACH
		ADS	ELINCR1
		TCF	RESETRPT

# THESE EQUIVALENCES ARE BASED ON GSOP CHAPTER 4, REVISION 16 OF P64LM

+ELBIT		=	BIT2		# -PITCH
-ELBIT		=	BIT1		# +PITCH
+AZBIT		=	BIT5
-AZBIT		=	BIT6

# Page 822
ALL4BITS	OCT	00063
AZEACH		DEC	.03491		# 2 DEGREES
ELEACH		DEC	.00873		# 1/2 DEGREE

# ****************************************************************
# R.O.D. TRAP
# ****************************************************************

		BANK	20
		SETLOC	RODTRAP
		BANK
		COUNT*	$$/F2DPS	# ************************

DESCBITS	MASK	BIT7		# COME HERE FROM MARKRUPT CODING WITH BIT
		CCS	A		#	7 OR 6 OF CHANNEL 16 IN A; BIT 7 MEANS
		CS	TWO		#	- RATE INCREMENT, BIT 6 + INCREMENT.
		AD	ONE
		ADS	RODCOUNT
		TCF	RESUME		# TRAP IS RESET WHEN SWITCH IS RELEASED

		BANK	31
		SETLOC	F2DPS*31
		BANK

		COUNT*	$$/F2DPS

# ***********************************************************************************
# DOUBLE PRECISION ROOT FINDER SUBROUTINE (BY ALLAN KLUMPP)
# ***********************************************************************************
#
#	                                               N        N-1
#	ROOTPSRS FINDS ONE ROOT OF THE POWER SERIES A X  + A   X    + ... + A X + A
#	                                             N      N-1              1     0
# USING NEWTON'S METHOD STARTING WITH AN INITIAL GUESS FOR THE ROOT.  THE ENTERING DATA MUST BE AS FOLLOWS:
#	A	SP	LOC-3		ADRES FOR REFERENCING PWR COF TABL
#	L	SP	N-1		N IS THE DEGREE OF THE POWER SERIES
#	MPAC	DP	X		INITIAL GUESS FOR ROOT
#
#	LOC-2N	DP	A(0)
#		...
#	LOC	DP	A(N)
#	LOC+2	SP	PRECROOT	 PREC RQD OF ROOT (AS FRACT OF 1ST GUESS)
#
# Page 823
# THE DP RESULT IS LEFT IN MPAC UPON EXIT, AND A SP COUNT OF THE ITERATIONS TO CONVERGENCE IS LEFT IN MPAC+2.
# RETURN IS NORMALLY TO LOC(TC ROOTPSRS)+3.  IF ROOTPSRS FAILS TO CONVERGE TO IN 8 PASSES, RETURN IS TO LOC+1 AND
# OUTPUTS ARE NOT TO BE TRUSTED.
#
# PRECAUTION:  ROOTPSRS MAKES NO CHECKS FOR OVERFLOW OR FOR IMPROPER USAGE.  IMPROPER USAGE COULD
# PRECLUDE CONVERGENCE OR REQUIRE EXCESSIVE ITERATIONS.  AS A SPECIFIC EXAMPLE, ROOTPSRS FORMS A DERIVATIVE
# COEFFICIENT TABLE BY MULTIPLYING EACH A(I) BY I, WHERE I RANGES FROM 1 TO N.  IF AN ELEMENT OF THE DERIVATIVE
# COEFFICIENT TABLE = 1 OR >1 IN MAGNITUDE, ONLY THE EXCESS IS RETAINED.  ROOTPSRS MAY CONVERGE ON THE CORRECT
# ROOT NONETHELESS, BUT IT MAY TAKE AN EXCESSIVE NUMBER OF ITERATIONS.  THEREFORE THE USER SHOULD RECOGNIZE:
#	1.  USER'S RESPONSIBILITY TO ASSUR THAT I X A(I) < 1 IN MAGNITUDE FOR ALL I.
#	2.  USER'S RESPONSIBILITY TO ASSURE OVERFLOW WILL NOT OCCUR IN EVALUATING EITHER THE RESIDUAL OR THE DERIVATIVE
#	    POWER SERIES.  THIS OVERFLOW WOULD BE PRODUCED BY SUBROUTINE POWRSERS, CALLED BY ROOTPSRS, AND MIGHT NOT
#	    PRECLUDE EVENTUAL CONVERGENCE.
#	3.  AT PRESENT, ERASABLE LOCATIONS ARE RESERVED ONLY FOR N UP TO 5.  AN N IN EXCESS OF 5 WILL PRODUCE CHAOS.
#	    ALL ERASABLES USED BY ROOTPSRS ARE UNSWITCHED LOCATED IN THE REGION FROM MPAC-33 OCT TO MPAC+7.
#	4.  THE ITERATION COUNT RETURNED IN MPAC+2 MAY BE USED TO DETECT ABNORMAL PERFORMANCE.

					# STORE ENTERING DATA, INITIALIZE ERASABLES
ROOTPSRS	EXTEND
		QXCH	RETROOT		# RETURN ADRES
		TS	PWRPTR		# PWR TABLE POINTER
		DXCH	MPAC +3		# PWR TABLE ADRES, N-1
		CA	DERTABLL
		TS	DERPTR		# DER TABL POINTER
		TS	MPAC +5		# DER TABL ADRES
		CCS	MPAC +4		# NO POWER SERIES DEGREE 1 OR LESS
		TS	MPAC +6		# N-2
		CA	ZERO		# MODE USED AS ITERATION COUNTER.  MODE
		TS	MODE		# MUST BE POS SO ABS WON'T COMP MPAC+3 ETC.

					# COMPUTE CRITERION TO STOP ITERATING
		EXTEND
		DCA	MPAC		# FETCH ROOT GUESS, KEEPING IT IN MPAC
		DXCH	ROOTPS		# AND IN ROOTPS
		INDEX	MPAC +3		# PWR TABLE ADRES
		CA	5		# PRECROOT TO A
		TC	SHORTMP		# YIELDS DP PRODUCT IN MPAC
		TC	USPRCADR
		CADR	ABS		# YIELDS ABVAL OF CRITERION ON DX IN MPAC
		DXCH	MPAC
		DXCH	DXCRIT		# CRITERION

					# SET UP DER COF TABL
# Page 824
		EXTEND
		INDEX	PWRPTR
		DCA	3
		DXCH	MPAC		# A(N) TO MPAC

		CA	MPAC +4		# N-1 TO A

DERCLOOP	TS	PWRCNT		# LOOP COUNTER
		AD	ONE
		TC	DMPNSUB		# YIELDS DERCOF = I X A(I) IN MPAC
		EXTEND
		INDEX	PWRPTR
		DCA	1
		DXCH	MPAC		# (I-1) TO MPAC, FETCHING DERCOF
		INDEX	DERPTR
		DXCH	3		# DERCOF TO DER TABLE
		CS	TWO
		ADS	PWRPTR		# DECREMENT PWR POINTER
		CS	TWO
		ADS	DERPTR		# DECREMENT DER POINTER
		CCS	PWRCNT
		TCF	DERCLOOP

					# CONVERGE ON ROOT
ROOTLOOP	EXTEND
		DCA	ROOTPS		# FETCH CURRENT ROOT
		DXCH	MPAC		# LEAVE IN MPAC
		EXTEND
		DCA	MPAC +5		# LOAD A, L WITH DER TABL ADRES, N-2
		TC	POWRSERS	# YIELDS DERIVATIVE IN MPAC

		EXTEND
		DCA	ROOTPS
		DXCH	MPAC		# CURRENT ROOT TO MPAC, FETCHING DERIVATIVE
		DXCH	BUF		# LEAVE DERIVATIVE IN BUF AS DIVISOR
		EXTEND
		DCA	MPAC +3		# LOAD A, L WITH PWR TABL ADRES, N-1
		TC	POWRSERS	# YIELDS RESIDUAL IN MPAC

		TC	USPRCADR
		CADR	DDV/BDDV	# YIELDS -DX IN MPAC

		EXTEND
		DCS	MPAC		# FETCH DX, LEAVING -DX IN MPAC
		DAS	ROOTPS		# CORRECTED ROOT NOW IN ROOTPS

		TC	USPRCADR
		CADR	ABS		# YIELDS ABS(DX) IN MPAC
		EXTEND
# Page 825
		DCS	DXCRIT
		DAS	MPAC		# ABS(DX)-ABS(DXCRIT) IN MPAC

		CA	MODE
		MASK	BIT4		# KLUMPP SAYS GIVE UP AFTER EIGHT PASSES
		CCS	A
BADROOT		TC	RETROOT

		INCR	MODE		# INCREMENT ITERATION COUNTER
		CCS	MPAC		# TEST HI ORDER DX
		TCF	ROOTLOOP
		TCF	TESTLODX
		TCF	ROOTSTOR
TESTLODX	CCS	MPAC +1		# TEST LO ORDER DX
		TCF	ROOTLOOP
		TCF	ROOTSTOR
		TCF	ROOTSTOR
ROOTSTOR	DXCH	ROOTPS
		DXCH	MPAC
		CA	MODE
		TS	MPAC +2		# STORE SP ITERATION COUNT IN MPAC+2
		INDEX	RETROOT
		TCF	2

DERTABLL	ADRES	DERCOFN -3

# ****************************************************************************
# TRASHY LITTLE SUBROUTINES
# ****************************************************************************

INTPRETX	INDEX	WCHPHASE	# SET X1 ON THE WAY TO THE INTERPRETER
		CS	TARGTDEX
		INDEX	FIXLOC
		TS	X1
		TCF	INTPRET

TDISPSET	CA	TTF/8
		EXTEND
		MP	TSCALINV
		DXCH	TTFDISP

		CA	EBANK5		# TREDES BECOMES ZERO TWO PASSES
		TS	EBANK		#	BEFORE TCGFAPPR IS REACHED
		EBANK=	TCGFAPPR
		CA	TCGFAPPR
		INCR	BBANK
		INCR	BBANK
		EBANK=	TTF/8
# Page 826
		AD	TTF/8
		EXTEND
		MP	TREDESCL
		AD	-DEC103
		AD	NEGMAX
		TS	L
		CS	L
		AD	L
		AD	+DEC99
		AD	POSMAX
		TS	TREDES
		CS	TREDES
		ADS	TREDES
		TC	Q

1406P00		TC	P00DOO
		OCT	01406
1406ALM		TC	ALARM
		OCT	01406
		TCF	RATESTOP

# *********************************************************************
# SPECIALIZED "PHASCHNG" SUBROUTINE
# *********************************************************************

		EBANK=	PHSNAME2
FASTCHNG	CA	EBANK3		# SPECIALIZED 'PHASCHNG' ROUTINE
		XCH	EBANK
		DXCH	L
		TS	PHSNAME3
		LXCH	EBANK
		EBANK=	E2DPS
		TC	A

# *************************************************************************************
# PARAMETER TABLE INDIRECT ADDRESSES
# *************************************************************************************

RDG		=	RBRFG
VDG		=	VBRFG
ADG		=	ABRFG
VDG2TTF		=	VBRFG*
ADG2TTF		=	ABRFG*
JDG2TTF		=	JBRFG*

# *************************************************************************************
# LUNAR LANDING CONSTANTS
# *************************************************************************************

# Page 827
TABLTTFL	ADRES	TABLTTF +3	# ADDRESS FOR REFERENCING TTF TABLE
TTFSCALE	=	BIT12
TSCALINV	=	BIT4
-DEC103		DEC	-103
+DEC99		DEC	+99
TREDESCL	DEC	-.08
180DEGS		DEC	+180
1/2DEG		DEC	+.00278
PROJMAX		DEC	.42262 B-3	# SIN(25')/8 TO COMPARE WITH PROJ
PROJMIN		DEC	.25882 B-3	# SIN(15')/8 TO COMPARE WITH PROJ
V06N63		VN	0663		# P63
V06N64		VN	0664		# P64
V06N60		VN	0660		# P65, P66, P67

		BANK	22
		SETLOC	LANDCNST
		BANK
		COUNT*	$$/F2DPS

HIGHESTF	2DEC	4.34546769 B-12
GSCALE		2DEC	100 B-11
3/8DP		2DEC	.375
3/4DP		2DEC	.750
DEPRCRIT	2DEC	-.02 B-1

# Page 828
# **************************************************************************
# **************************************************************************