### FILE="Main.annotation"
## Copyright:   Public domain.
## Filename:    POWERED_FLIGHT_SUBROUTINES.agc
## Purpose:     The main source file for Luminary revision 069.
##              It is part of the source code for the original release
##              of the flight software for the Lunar Module's (LM) Apollo
##              Guidance Computer (AGC) for Apollo 10. The actual flown
##              version was Luminary 69 revision 2, which included a
##              newer lunar gravity model and only affected module 2.
##              This file is intended to be a faithful transcription, except
##              that the code format has been changed to conform to the
##              requirements of the yaYUL assembler rather than the
##              original YUL assembler.
## Reference:   pp. 1254-1261
## Assembler:   yaYUL
## Contact:     Ron Burkey <info@sandroid.org>.
## Website:     www.ibiblio.org/apollo/index.html
## Mod history: 2016-12-13 MAS  Created from Luminary 99.
##              2016-12-18 MAS  Updated from comment-proofed Luminary 99 version.
##		2017-01-13 RRB	Updated for Luminary 69.
##		2017-01-28 RSB	Proofed comment text using octopus/prooferComments
##				but no errors found.
##		2017-03-16 RSB	Comment-text fixes identified in 5-way
##				side-by-side diff of Luminary 69/99/116/131/210.
##		2017-03-17 RSB	Comment-text fixes identified in diff'ing
##				Luminary 99 vs Comanche 55.
##              2021-05-30 ABS  SINSLOC -> SINESLOC

## Page 1254
		BANK	14		# SAME FBANK AS THE FINDCDUD SUB-PROGRAM
		SETLOC	POWFLITE
		BANK

		EBANK=	DEXDEX
		COUNT*	$$/POWFL

#     CDUTRIG, CDUTRIG1, CDUTRIG2, AND CD*TR*GS ALL COMPUTE THE SINES AND
# COSINES OF THREE 2'S COMPLEMENT ANGLES AND PLACE THE RESULT, DOUBLE
# PRECISION, IN THE SAME ORDER AS THE INPUTS, AT SINCDU AND COSCDU.   AN
# ADDITIONAL OUTPUT IS THE 1'S COMPLEMENT ANGLES AT CDUSPOT.   THESE
# ROUTINES GO OUT OF THEIR WAY TO LEAVE THE MPAC AREA AS THEY FIND IT,
# EXCEPT FOR THE GENERALLY UNIMPORTANT MPAC +2.  THEY DIFFER ONLY IN
# WHERE THEY GET THE ANGLES, AND IN METHOD OF CALLING.
#
#     CDUTRIG (AND CDUTRIG1, WHICH CAN BE CALLED IN BASIC) COMPUTE THE
# SINES AND COSINES FROM THE CURRENT CONTENTS OF THE CDU REGISTERS.
# THE CONTENTS OF CDUTEMP, ETC., ARE NOT TOUCHED SO THAT THEY MAY
# CONTINUE TO FORM A CONSISTENT SET WITH THE LATEST PIPA READINGS.
#
#     CDUTRIG1 IS LIKE CDUTRIG EXCEPT THAT IT CAN BE CALLED IN BASIC.
#
#     CD*TR*GS FINDS CDU VALUES IN CDUSPOT RATHER THAN IN CDUTEMP.   THIS
# ALLOWS USERS TO MAKE TRANSFORMATIONS USING ARBITRARY ANGLES, OR REAL
# ANGLES IN AN ORDER OTHER THAN X Y Z.   A CALL TO THIS ROUTINE IS
# NECESSARY IN PREPARATION FOR A CALL TO AX*SR*T IN EITHER OF ITS TWO
# MODES (SMNB OR NBSM).   SINCE AX*SR*T EXPECTS TO FIND THE SINES AND
# COSINES IN THE ORDER Y Z X THE ANGLES MUST HAVE BEEN PLACED IN CDUSPOT
# IN THIS ORDER.   CD*TR*GS NEED NOT BE REPEATED WHEN AX*SR*T IS CALLED
# MORE THAN ONCE, PROVIDED THE ANGLES HAVE NOT CHANGED.   NOTE THAT SINCE
# IT CLOBBERS BUF2 (IN THE SINE AND COSINE ROUTINES) CD*TR*GS CANNOT BE
# CALLED USING BANKCALL.   SORRY.
#
#     CD*TR*G IS LIKE CD*TR*GS EXCEPT THAT IT CAN BE CALLED IN
# INTERPRETIVE.

CDUTRIG		EXIT
		TC	CDUTRIGS
		TC	INTPRET
		RVQ

CD*TR*G		EXIT
		TC	CD*TR*GS
		TC	INTPRET
		RVQ

CDUTRIGS	CA	CDUX
		TS	CDUSPOT +4
		CA	CDUY
		TS	CDUSPOT
## Page 1255
		CA	CDUZ
		TS	CDUSPOT +2

CD*TR*GS	EXTEND
		QXCH	TEM2
		CAF	FOUR
TR*GL**P	MASK	SIX		# MAKE IT EVEN AND SMALLER
		TS	TEM3
		INDEX	TEM3
		CA	CDUSPOT
		DXCH	MPAC		# STORING 2'S COMP ANGLE, LOADING MPAC
		DXCH	VBUF 	+4	# STORING MPAC FOR LATER RESTORATION
		TC	USPRCADR
		CADR	CDULOGIC
		EXTEND
		DCA	MPAC
		INDEX	TEM3
		DXCH	CDUSPOT		# STORING 1'S COMPLEMENT ANGLE
		TC	USPRCADR
		CADR	COSINE
		DXCH	MPAC
		INDEX	TEM3
		DXCH	COSCDU		# STORING COSINE
		EXTEND
		INDEX	TEM3
		DCA	CDUSPOT		# LOADING 1'S COMPLEMENT ANGLE
		TC	USPRCADR
		CADR	SINE 	+1	# SINE +1 EXPECTS ARGUMENT IN A AND L
		DXCH	VBUF 	+4	# BRINGING UP PRIOR MPAC TO BE RESTORED
		DXCH	MPAC
		INDEX	TEM3
		DXCH	SINCDU
		CCS	TEM3
		TCF	TR*GL**P
		TC	TEM2
## Page 1256
# ****************************************************************************************************************
#     QUICTRIG, INTENDED FOR GUIDANCE CYCLE USE WHERE TIME IS CRITICAL, IS A MUCH FASTER VERSION OF CD*TR*GS.
# QUICTRIG COMPUTES AND STORES THE SINES AND COSINES OF THE 2'S COMPLEMENT ANGLES AT CDUSPOT, CDUSPOT +2,
# AND CDUSPOT +4.   UNLIKE CD*TR*GS, QUICTRIG DOES NOT LEAVE THE 1'S COMPLEMENT VERSIONS OF THE ANGLES IN
# CDUSPOT.   QUICTRIG'S EXECUTION TIME IS 4.1 MS;  THIS IS 10 TIMES AS FAST AS CD*TR*GS.    QUICTRIG MAY BE
# CALLED FROM INTERPRETIVE AS AN RTB OP-CODE, OR FROM BASIC VIA BANKCALL OR IBNKCALL.

QUICTRIG	INHINT			# INHINT SINCE DAP USES THE SAME TEMPS
		EXTEND
		QXCH	ITEMP1
		CAF	FOUR
 +4		MASK	SIX
		TS	ITEMP2
		INDEX	ITEMP2
		CA	CDUSPOT
		TC	SPSIN
		EXTEND
		MP	BIT14		# SCALE DOWN TO MATCH INTERPRETER OUTPUTS
		INDEX	ITEMP2
		DXCH	SINCDU
		INDEX	ITEMP2
		CA	CDUSPOT
		TC	SPCOS
		EXTEND
		MP	BIT14
		INDEX	ITEMP2
		DXCH	COSCDU
		CCS	ITEMP2
		TCF	QUICTRIG +4
		CA	ITEMP1
		RELINT
		TC	A

## Page 1257
# ****************************************************************************************************************
#     THESE INTERFACE ROUTINES MAKE IT POSSIBLE TO CALL AX*SR*T, ETC., IN
# INTERPRETIVE.  LATER, WHERE POSSIBLE, THEY WILL BE ELIMINATED.
#
#     THESE INTERFACE ROUTINES ARE PERMANENT.   ALL RESTORE USER'S EBANK
# SETTING.   ALL ARE STRICT INTERPRETIVE SUBROUTINES, CALLED USING "CALL",
# RETURNING VIA QPRET.   ALL EXPECT AND RETURN THE VECTOR TO BE TRANSFOR-
# MED INTERPRETER-STYLE IN MPAC; COMPONENTS AT MPAC, MPAC +3, AND MPAC +5.
#
#      TRG*SMNB AND TRG*NBSM BOTH EXPECT TO SEE THE 2'S COMPLEMENT ANGLES
# AT CDUSPOT (ORDER Y Z X, AT CDUSPOT, CDUSPOT +2, AND CDUSPOT +4; ODD
# LOCATIONS NEED NOT BE ZEROED).   TRG*NBSM DOES THE NB TO SM TRANSFOR-
# MATION;  TRG*SMNB, VICE VERSA.
#
#     CDU*NBSM DOES ITS TRANSFORMATION USING THE PRESENT CONTENTS OF
# THE CDU COUNTERS.   OTHERWISE IT IS LIKE TRG*NBSM.
#
#     CDU*SMNB IS THE COMPLEMENT OF CDU*NBSM.

CDU*SMNB	EXIT
		TC	CDUTRIGS
		TCF	C*MM*N1

TRG*SMNB	EXIT
		TC	CD*TR*GS
C*MM*N1		TC	MPACVBUF	# AX*SR*T EXPECTS VECTOR IN VBUF
		CS	THREE		# SIGNAL FOR SM TO NB TRANSFORMATION
C*MM*N2		TC	AX*SR*T
		TC	INTPRET
		VLOAD	RVQ
			VBUF

CDU*NBSM	EXIT
		TC	CDUTRIGS
		TCF	C*MM*N3

TRG*NBSM	EXIT
		TC	CD*TR*GS
C*MM*N3		TC	MPACVBUF	# FOR AX*SR*T
		CA	THREE		# SIGNAL FOR NB TO SM TRANSFORMATION
		TCF	C*MM*N2

#     *NBSM* AND *SMNB* EXPECT TO SEE THE SINES AND COSINES (AT SINCDU
# AND COSCDU) RATHER THAN THE ANGLES THEMSELVES.   OTHERWISE THEY ARE
# LIKE TRG*NBSM AND TRG*SMNB.
#
#      NOTE THAT JUST AS CD*TR*GS NEED BE CALLED ONLY ONCE FOR EACH SERIES
# OF TRANSFORMATIONS USING THE SAME ANGLES, SO TOO ONLY ONE OF TRG*NBSM
## Page 1258
# AND TRG*SMNB NEED BE CALLED FOR EACH SERIES.   FOR SUBSEQUENT TRANSFOR-
# MATIONS USE *NBSM* AND *SMNB*.

*SMNB*		EXIT
		TCF	C*MM*N1

*NBSM*		EXIT
		TCF	C*MM*N3

#       AX*SR*T COMBINES THE OLD SMNB AND NBSM.   FOR THE NB TO SM
# TRANSFORMATION, ENTER WITH +3 IN A.   FOR SM TO NB, ENTER WITH -3.
# THE VECTOR TO BE TRANSFORMED ARRIVES, AND IS RETURNED, IN VBUF.
# AX*SR*T EXPECTS TO FIND THE SINES AND COSINES OF THE ANGLES OF ROTATION
# AT SINCDU AND COSCDU, IN THE ORDER Y Z X.  A CALL TO CD*TR*GS, WITH
# THE 2'S COMPLEMENT ANGLES (ORDER Y Z X) AT CDUSPOT, WILL TAKE CARE OF
# THIS.  HERE IS A SAMPLE CALLING SEQUENCE:-
#		TC	CDUTRIGS
#		CS	THREE		("CA THREE" FOR NBSM)
#		TC	AX*SR*T
# THE CALL TO CD*TR*GS NEED NOT BE REPEATED, WHEN AX*SR*T IS CALLED MORE
# THAN ONCE, UNLESS THE ANGLES HAVE CHANGED.
#
#     AX*SR*T IS GUARANTEED SAFE ONLY FOR VECTORS OF MAGNITUDE LESS THAN
# UNITY.   A LOOK AT THE CASE IN WHICH A VECTOR OF GREATER MAGNITUDE
# HAPPENS TO LIE ALONG AN AXIS OF THE SYSTEM TO WHICH IT IS TO BE TRANS-
# FORMED CONVINCES ONE THAT THIS IS A RESTRICTION WHICH MUST BE ACCEPTED.

AX*SR*T		TS	DEXDEX		# WHERE IT BECOMES THE INDEX OF INDEXES
		EXTEND
		QXCH	RTNSAVER

R*TL**P		CCS	DEXDEX		#       	+3 --> 0	-3 --> 2
		CS	DEXDEX		# THUS:		+2 --> 1	-2 --> 1
		AD	THREE		#		+1 --> 2	-1 --> 0
		EXTEND
		INDEX	A
		DCA	INDEXI
		DXCH	DEXI

		CA	ONE
		TS	BUF
		EXTEND
		INDEX	DEX1
		DCS	VBUF
		TCF	LOOP1		# REALLY BE A SUBTRACT, AND VICE VERSA

LOOP2		DXCH	BUF		# LOADING VECTOR COMPONENT, STORING INDEX
## Page 1259
LOOP1		DXCH	MPAC
		CA	SINESLOC
		AD	DEX1
		TS	ADDRWD

		TC	DMPSUB		# MULTIPLY BY SIN(CDUANGLE)
		CCS	DEXDEX
		DXCH	MPAC		# NBSM CASE
		TCF	+3
		EXTEND			# SMNB CASE
		DCS	MPAC
		DXCH	TERM1TMP

		CA	SIX		# SINCDU AND COSCDU (EACH 6 WORDS) MUST
		ADS	ADDRWD		#   BE CONSECUTIVE AND IN THAT ORDER

		EXTEND
		INDEX	BUF
		INDEX	DEX1
		DCA	VBUF
		DXCH	MPAC
		TC	DMPSUB		# MULTIPLY BY COS(CDUANGLE)
		DXCH	MPAC
		DAS	TERM1TMP
		DXCH	TERM1TMP
		DDOUBL
		INDEX	BUF
		INDEX	DEX1
		DXCH	VBUF
		DXCH	BUF		# LOADING INDEX, STORING VECTOR COMPONENT
		
		CCS	A		# 'CAUSE THAT'S WHERE THE INDEX NOW IS
		TCF	LOOP2

		EXTEND
		DIM	DEXDEX		# DECREMENT MAGNITUDE PRESERVING SIGN

TSTPOINT	CCS	DEXDEX		# ONLY THE BRANCHING FUNCTION IS USED
		TCF	R*TL**P
		TC	RTNSAVER
		TCF	R*TL**P
		TC	RTNSAVER

SINESLOC	ADRES	SINCDU		# FOR USE IN SETTING ADDRWD

INDEXI		DEC	4		# **********   DON'T   **********
		DEC	2		# **********   TOUCH   **********
		DEC	0		# **********   THESE   **********
## Page 1260
		DEC	4		# ********** CONSTANTS **********

# ****************************************************************************************************************
## Page 1261
# THIS SUBROUTINE COMPUTES INCREMENTAL CHANGES IN CDU(GIMBAL) ANGLES FROM INCREMENTAL CHANGES ABOUT SM AXES. IT
# REQUIRES SM INCREMENTS AS A DP VECTOR SCALED AT ONE REVOLUTION(DTHETASM,+2,+4).  SIN,COS(CDUY,Z,X) ARE IN
# SINCDU,+2,+4 AND COSCDU,+2,+4 RESPECTIVELY,SCALED TO ONE HALF. CDU INCREENTS ARE PLACED IN DCDU,+2,+4 SCALED TO
# ONE REVOLUTION.

#        *  COS(IGA)SEC(MGA)          0           -SIN(IGA)SEC(MGA) *
#        *                                                          *
#        * -COS(IGA)TAN(MGA)          1            SIN(IGA)TAN(MGA) *
#        *                                                          *
#        *      SIN(IGA)              0                COS(IGA)     *

		BANK	14
		SETLOC	POWFLIT1
		BANK
SMCDURES	DLOAD	DMP
			DTHETASM
			COSCDUY

		PDDL	DMP
			DTHETASM +4
			SINCDUY

		BDSU
		DDV
			COSCDUZ
		STORE	DCDU

		DMP	SL1		# SCALE
			SINCDUZ
		BDSU

			DTHETASM +2
		STODL	DCDU +2
			DTHETASM

		DMP	PDDL
			SINCDUY
			DTHETASM +4

		DMP	DAD
			COSCDUY
		SL1
		STORE	DCDU +4
		RVQ