Apollo-11/DAP_INTERFACE_SUBROUTINES.s

# Copyright:	Public domain.
# Filename:	DAP_INTERFACE_SUBROUTINES.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:	Ron Burkey <info@sandroid.org>.
# Website:	www.ibiblio.org/apollo.
# Pages:	1406-1409
# Mod history:  2009-05-10 SN   (Sergio Navarro).  Started adapting
#				from the Luminary131/ file of the same
#				name, using Luminary099 page images.
#
# 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 1406
		BANK	20
		SETLOC	DAPS3
		BANK

		EBANK=	CDUXD
		COUNT*	$$/DAPIF

# MOD 0		DATE	11/15/66	BY GEORGE W. CHERRY
# MOD 1			 1/23/67	MODIFICATION BY PETER ADLER
#
# FUNCTIONAL DESCRIPTION
#	HEREIN IS A COLLECTION OF SUBROUTINES WHICH ALLOW MISSION CONTROL PROGRAMS TO CONTROL THE MODE
#	AND INTERFACE WITH THE DAP.
#
# CALLING SEQUENCES
#	IN INTERRUPT OR WITH INTERRUPT INHIBITED
#		TC	IBNKCALL
#		FCADR	ROUTINE
#	IN A JOB WITHOUT INTERRUPT INHIBITED
#		INHINT
#		TC	IBNKCALL
#		FCADR	ROUTINE
#		RELINT
#
# OUTPUT
#	SEE INDIVIDUAL ROUTINES BELOW
#
# DEBRIS
#	A, L, AND SOMETIMES MDUETEMP			ODE	NOT IN PULSES MODE

# Page 1407
# SUBROUTINE NAMES:
#	SETMAXDB, SETMINDB, RESTORDB, PFLITEDB
# MODIFIED:	30 JANUARY 1968 BY P. S. WEISSMAN TO CREATE RESTORDB.
# MODIFIED:	1 MARCH 1968 BY P. S. WEISSMAN TO SAVE EBANK AND CREATE PFLITEDB
#
# FUNCTIONAL DESCRIPTION:
#	SETMAXDB -- SET DEADBAND TO 5.0 DEGREES
#	SETMINDB -- SET DEADBAND TO 0.3 DEGREE
#	RESTORDB -- SET DEADBAND TO MAX OR MIN ACCORDING TO SETTINGS OF DBSELECT BIT OF DAPBOOLS
#	PFLITEDB -- SET DEADBAND TO 1.0 DEGREE AND ZERO THE COMMANDED ATTITUDE CHANGE AND COMMANDED RATE
#
#	ALL ENTRIES SET UP A NOVAC JOB TO DO 1/ACCS SO THAT THE TJETLAW SWITCH CURVES ARE POSITIONED TO
#	REFLECT TEH NEW DEADBAND.  IT SHOULD BE NOTED THAT THE DEADBAND REFERS TO THE ATTITUDE IN THE P-, U-, AND V-AXES.
#
# SUBROUTINE CALLED:	NOVAC
#
# CALLING SEQUENCE:	SAME AS ABOVE
#			OR	TC RESTORDB +1    FROM ALLCOAST
#
# DEBRIS:		A, L, Q, RUPTREG1, (ITEMPS IN NOVAC)

RESTORDB	CAE	DAPBOOLS	# DETERMINE CREW-SELECTED DEADBAND.
		MASK	DBSELECT
		EXTEND
		BZF	SETMINDB

SETMAXDB	CAF	WIDEDB		# SET 5 DEGREE DEADBAND.
	+1	TS	DB

		EXTEND			# SET UP JOB TO RE-POSITION SWITCH CURVES.
		QXCH	RUPTREG1
CALLACCS	CAF	PRIO27
		TC	NOVAC
		EBANK=	AOSQ
		2CADR	1/ACCJOB

		TC	RUPTREG1	# RETURN TO CALLER.

SETMINDB	CAF	NARROWDB	# SET 0.3 DEGREE DEADBAND.
		TCF	SETMAXDB +1

PFLITEDB	EXTEND			# THE RETURN FROM CALLACCS IS TO RUPTREG1.
		QXCH	RUPTREG1
		TC	ZATTEROR	# ZERO THE ERRORS AND COMMANDED RATES.
		CAF	POWERDB		# SET DB TO 1.0 DEG.
		TS	DB
		TCF	CALLACCS	# SET UP 1/ACCS AND RETURN TO CALLER.
NARROWDB	OCTAL	00155		# 0.3 DEGREE SCALED AT 45.
# Page 1408
WIDEDB		OCTAL	03434		# 5.0 DEGREES SCALED AT 45.
POWERDB		DEC	.02222		# 1.0 DEGREE SCALED AT 45.

ZATTEROR	CAF	EBANK6
		XCH	EBANK
		TS	L		# SAVE CALLERS EBANK IN L.
		CAE	CDUX
		TS	CDUXD
		CAE	CDUY
		TS	CDUYD
		CAE	CDUZ
		TS	CDUZD
		TCF	STOPRATE +3

STOPRATE	CAF	EBANK6
		XCH	EBANK
		TS	L		# SAVE CALLERS EBANK IN L.
	+3	CAF	ZERO
		TS	OMEGAPD
		TS	OMEGAQD
		TS	OMEGARD
		TS	DELCDUX
		TS	DELCDUY
		TS	DELCDUZ
		TS	DELPEROR
		TS	DELQEROR
		TS	DELREROR
		LXCH	EBANK		# RESTORE CALLERS EBANK.
		TC	Q

# SUBROUTINE NAME:	ALLCOAST
# WILL BE CALLED BY FRESH STARTS AND ENGINE OFF ROUTINES.
#
# CALLING SEQUENCE:	(SAME AS ABOVE)
#
# EXIT:			RETURN TO Q.
#
# SUBROUTINES CALLED:	STOPRATE, RESTORDB, NOVAC
#
# ZERO:			(FOR ALL AXES) AOS, ALPHA, AOSTERM, OMEGAD, DELCDU, DELEROR
#
# OUTPUT:		DRIFTBIT/DAPBOOLS, OE, JOB TO DO 1/ACCS
#
# DEBRIS:		A, L, Q, RUPTREG1, RUPTREG2, (ITEMPS IN NOVAC)

ALLCOAST	EXTEND			# SAVE Q FOR RETURN
		QXCH	RUPTREG2
# Page 1409
		TC	STOPRATE	# CLEAR RATE INTERFACE.  RETURN WITH A=0
		LXCH	EBANK		# AND L=EBANK6.  SAVE CALLER'S EBANK.
		TS	AOSQ
		TS	AOSQ +1
		TS	AOSR
		TS	AOSR +1
		TS	ALPHAQ		# FOR DOWNLIST.
		TS	ALPHAR
		TS	AOSQTERM
		TS	AOSRTERM
		LXCH	EBANK		# RESTORE EBANK (EBANK6 NO LONGER NEEDED)

		CS	DAPBOOLS	# SET UP DRIFTBIT
		MASK	DRIFTBIT
		ADS	DAPBOOLS
		TC	RESTORDB +1	# RESTORE DEADBANK TO CREW-SELECTED VALUE.

		TC	RUPTREG2	# RETURN.