### FILE="Main.annotation"
## Copyright:   Public domain.
## Filename:	KEYRUPT_UPRUPT.agc
## Purpose:     Part of the source code for Colossus build 237.
##              This is for the Command Module's (CM) Apollo Guidance
##              Computer (AGC), for Apollo 8.
## Assembler:   yaYUL
## Contact:     Jim Lawton <jim DOT lawton AT gmail DOT com>
## Website:     www.ibiblio.org/apollo/index.html
## Page Scans:  www.ibiblio.org/apollo/ScansForConversion/Colossus237/
## Mod history: 2011-04-17 JL	Adapted from corresponding Colossus 249 file.
##		2017-01-01 RSB	Proofed comment text using octopus/ProoferComments,
##				and fixed errors found.
##		2017-01-15 RSB	Fixed comment-text errors identified by diff'ing
##				against Colossus 249.
##		2017-03-13 RSB	Comment-text fixes noted in proofing Luminary 116.
##		2021-05-30 ABS	UPCK -> UPOK

## Page 1413
		BANK	14
		SETLOC	KEYRUPT
		BANK
		COUNT*	$$/KEYUP

KEYRUPT1	TS	BANKRUPT
		XCH	Q
		TS	QRUPT
		TC	LODSAMPT	# TIME IS SNATCHED IN RUPT FOR NOUN 65.
		CAF	LOW5
		EXTEND
		RAND	MNKEYIN		# CHECK IF KEYS 5M-1M ON
KEYCOM		TS	RUPTREG4
		CS	FLAGWRD5
		MASK	BIT15
		ADS	FLAGWRD5

ACCEPTUP	CAF	CHRPRIO		# (NOTE: RUPTREG4 = KEYTEMP1)
		TC	NOVAC
		EBANK=	DSPCOUNT
		2CADR	CHARIN
		CA	RUPTREG4
		INDEX	LOCCTR
		TS	MPAC		# LEAVE 5 BIT KEY CDE IN MPAC FOR CHARIN
		TC	RESUME

## Page 1414
# UPRUPT PROGRAM

UPRUPT		TS	BANKRUPT
		XCH	Q
		TS	QRUPT
		TC	LODSAMPT	# TIME IS SNATCHED IN RUPT FOR NOUN 65.
		CAF	ZERO
		XCH	INLINK
		TS	KEYTEMP1
		CAF	BIT3		# TURN ON UPACT LIGHT
		EXTEND			# (BIT 3 OF CHANNEL 11)
		WOR	DSALMOUT
UPRPT1		CAF	LOW5		# TEST FOR TRIPLE CHAR REDUNDANCY
		MASK	KEYTEMP1	# LOW5 OF WORD
		XCH	KEYTEMP1	# LOW5 INTO KEYTEMP1
		EXTEND
		MP	BIT10		# SHIFT RIGHT 5
		TS	KEYTEMP2
		MASK	LOW5		# MID 5
		AD	HI10
		TC	UPTEST
		CAF	BIT10
		EXTEND
		MP	KEYTEMP2	# SHIFT RIGHT 5
		MASK	LOW5		# HIGH 5
		COM
		TC	UPTEST

UPOK		CS	ELRCODE		# CODE IS GOOD. IF CODE = 'ERROR RESET',
		AD	KEYTEMP1	# CLEAR UPLOCKFL(SET BIT4 OF FLAGWRD7 = 0)
		EXTEND			# IF CODE DOES NOT = 'ERROR RESET', ACCEPT
		BZF	CLUPLOCK	# CODE ONLY IF UPLOCKFL IS CLEAR (=0).

		CAF	BIT4		# TEST UPLOCKFL FOR 0 OR 1.
		MASK	FLAGWRD7
		CCS	A
		TC	RESUME		# UPLOCKFL = 1
		TC	ACCEPTUP	# UPLOCKFL = 0

CLUPLOCK	CS	BIT4		# CLEAR UPLOCKFL (I.E., SET BIT 4 OF
		MASK	FLAGWRD7	# FLAGWRD7 = 0)
		TS	FLAGWRD7
		TC	ACCEPTUP

#					  CODE IS BAD
TMFAIL2		CS	FLAGWRD7	# LOCK OUT FURTHER UPLINK ACTIVITY
		MASK	BIT4		# (BY SETTING UPLOCKFL = 1) UNTIL
		ADS	FLAGWRD7	# 'ERROR RESET' IS SENT VIA UPLINK.
		TC	RESUME
UPTEST		AD	KEYTEMP1
## Page 1415
		CCS	A
		TC	TMFAIL2
HI10		OCT	77740
		TC	TMFAIL2
		TC	Q

ELRCODE		OCT	22

# 'UPLINK ACTIVITY LIGHT' IS TURNED OFF BY .....
#          1.     VBRELDSP
#          2.     ERROR RESET
#          3.     UPDATE PROGRAM(P27) ENTERED BY V70,V71,V72,AND V73.


#			            -
# THE RECEPTION OF A BAD CODE(I.E  CCC FAILURE) LOCKS OUT FURTHER UPLINK ACTIVITY BY SETTING BIT4 OF FLAGWRD7 = 1.
# THIS INDICATION WILL BE TRANSFERRED TO THE GROUND BY THE DOWNLINK WHICH DOWNLINKS ALL FLAGWORDS.
# WHEN UPLINK ACTIVITY IS LOCKED OUT ,IT CAN BE ALLOWED WHEN THE GROUND UPLINKS AND 'ERROR RESET' CODE.
# (IT IS RECOMMENDED THAT THE 'ERROR LIGHT RESET' CODE IS PRECEEDED BY 16 BITS THE FIRST OF WHICH IS 1 FOLLOWED
# BY 15 ZEROES. THIS WILL ELIMINATE EXTRANEOUS BITS FROM INLINK WHICH MAY HAVE BEEN LEFT OVER FROM THE ORIGINAL
# FAILURE)
# UPLINK ACTIVITY IS ALSO ALLOWED(UNLOCKED) DURING FRESH START WHEN FRESH START SETS BIT4 OF FLAGWRD7 = 0.