### FILE="Main.annotation"
## Copyright:   Public domain.
## Filename:    RADAR_LEADIN_ROUTINES.agc
## Purpose:     A section of LUM69 revision 2.
##              It is part of the reconstructed source code for the flown
##              version of the flight software for the Lunar Module's (LM)
##              Apollo Guidance Computer (AGC) for Apollo 10. The code has
##              been recreated from a copy of Luminary revsion 069, using
##              changes present in Luminary 099 which were described in
##              Luminary memos 75 and 78. The code has been adapted such
##              that the resulting bugger words exactly match those specified
##              for LUM69 revision 2 in NASA drawing 2021152B, which gives
##              relatively high confidence that the reconstruction is correct.
## Reference:   pp. 502-503
## Assembler:   yaYUL
## Contact:     Ron Burkey <info@sandroid.org>.
## Website:     www.ibiblio.org/apollo/index.html
## Mod history: 2019-07-27 MAS  Created from Luminary 69.

## Page 502
		BANK	25
		SETLOC	RRLEADIN
		BANK
		
		EBANK=	RSTACK
		
# RADAR SAMPLING LOOP.

		COUNT*	$$/RLEAD
RADSAMP		CCS	RSAMPDT		# TIMES NORMAL ONCE-PER-SECOND SAMPLING.
		TCF	+2
		TCF	TASKOVER	# +0 INSERTED MANUALLY TERMINATES TEST.
		
		TC	WAITLIST
		EBANK=	RSTACK
		2CADR	RADSAMP
		
		CAF	PRIO25
		TC	NOVAC
		EBANK=	RSTACK
		2CADR	DORSAMP
		
		CAF	BIT14		# FOR CYCLIC SAMPLING, RTSTDEX=
		EXTEND			# RTSTLOC/2 + RTSTBASE
		MP	RTSTLOC
		AD	RTSTBASE	# 0 FOR RR, 2 FOR LR.
		TS	RTSTDEX
		TCF	TASKOVER
		
# DO THE ACTUAL RADAR SAMPLE.

DORSAMP		TC	VARADAR		# SELECTS VARIABLE RADAR CHANNEL.
		TC	BANKCALL
		CADR	RADSTALL
		
		INCR	RFAILCNT	# ADVANCE FAIL COUNTER BUT ACCEPT BAD DATA
		
DORSAMP2	INHINT
		CA	FLAGWRD5	# DON'T UPDATE RSTACK IF IN R77.
		MASK	R77FLBIT
		CCS	A
		TCF	+4
		
		DXCH	SAMPLSUM
		INDEX	RTSTLOC
		DXCH	RSTACK
		
		CS	RTSTLOC		# CYCLE RTSTLOC.
		AD	RTSTMAX
		EXTEND
		
## Page 503		
		BZF	+3
		CA	RTSTLOC
		AD	TWO		# STORAGE IS DP
		TS	RTSTLOC
		TCF	ENDOFJOB	# CONTINUOUS SAMPLING AND 2N TRIES - GONE.
		
# VARIABLE RADAR DATA CALLER FOR ONE MEASUREMENT ONLY.

VARADAR		CAF	ONE		# WILL BE SENT TO RADAR ROUTINE IN A BY
		TS	BUF2		# SWCALL.
		INDEX	RTSTDEX
		CAF	RDRLOCS
		TCF	SWCALL		# NOT TOUCHING Q.
		
RDRLOCS		CADR	RRRANGE		# = 0
		CADR	RRRDOT		# = 1
		CADR	LRVELX		# = 2
		CADR	LRVELY		# = 3
		CADR	LRVELZ		# = 4
		CADR	LRALT		# = 5