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05 April 2024, 22:44:17 UTC
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 
Fixed a potential string-overflow bug in yaASM.  Removed timestamps from
 
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
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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
Tip revision: 078c79d
GIMBAL_LOCK_AVOIDANCE.agc 
### FILE="Main.annotation"
## Copyright:   Public domain.
## Filename:    GIMBAL_LOCK_AVOIDANCE.agc
## Purpose:     A section of Artemis revision 071.
##              It is part of the reconstructed source code for the first
##              release of the flight software for the Command Module's
##              (CM) Apollo Guidance Computer (AGC) for Apollo 15 through
##              17. The code has been recreated from a copy of Artemis 072.
##              It has been adapted such that the resulting bugger words
##              exactly match those specified for Artemis 071 in NASA
##              drawing 2021154-, which gives relatively high confidence
##              that the reconstruction is correct.
## Reference:   416
## Assembler:   yaYUL
## Contact:     Ron Burkey <info@sandroid.org>.
## Website:     www.ibiblio.org/apollo/index.html
## Mod history: 2019-08-14 MAS  Created from Artemis 072.

## Page 416
		
		SETLOC	KALCMON1
		BANK
		
		COUNT*	$$/KALC
		EBANK=	BCDU
		
# DETECTING GIMBAL LOCK
LOCSKIRT	EQUALS	WCALC
WCALC		LXC,1	DLOAD*
			RATEINDX
			ARATE,1	
		SR4	CALL		# COMPUTE THE INCREMENTAL ROTATION MATRIX
			DELCOMP		# DEL CORRESPONDING TO A 1 SEC ROTATION
					# ABOUT COF
		DLOAD*	VXSC
			ARATE,1
			COF
		MXV
			QUADROT
		STODL	BRATE	
			AM
		DMP	DDV*
			ANGLTIME
			ARATE,1
		SR
			5
		STORE	TM
		BON	VLOAD
			CYC61FLG
			RCYCLR61
			BRATE
		VXSC
			BIASCALE
		STORE	BIASTEMP	# ATTITUDE ERROR BIAS TO PREVENT OVERSHOOT
					# IN SYSTEM
		SETGO			# STATE SWITCH CALCMAN2 (43D)
			CALCMAN2	# 0(OFF) = BYPASS STARTING PROCEDURE
			NEWANGL +1	# 1(ON) = START MANEUVER
			
			
ARATE		2DEC	.0022222222	# = .05 DEG/SEC
		2DEC	.0088888889	# = .2 DEG/SEC
		2DEC	.0222222222	# = .5 DEG/SEC
		2DEC	.0888888889	# = 2 DEG/SEC                $22.5 DEG/SEC
ANGLTIME	2DEC	.000190735	# = 100B - 19
					# MANEUVER ANGLE TO MANEUVER TIME
## Page 417
QUADROT		2DEC	.1		# ROTATION MATRIX FROM S/C AXES TO CONTROL
		2DEC	0		# AXES (X ROT = -7.25 DEG)
		2DEC	0
		2DEC	0
		2DEC	.099200		# =(.1)COS7.25
		2DEC	-.012620	# =-(.1)SIN7.25
		2DEC	0
		2DEC	.012620		# (.1)SIN7.25
		2DEC	.099200		# (.1)COS7.25
BIASCALE	2DEC	.0002543132	# = (450/180)(1/0.6)(1/16384)
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