Raw File
INPUT_OUTPUT_CHANNEL_BIT_DESCRIPTIONS.agc
# Copyright:	Public domain.
# Filename:	INPUT_OUTPUT_CHANNEL_BIT_DESCRIPTIONS.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:	Onno Hommes <ohommes@cmu.edu>.
# Website:	www.ibiblio.org/apollo.
# Pages:	0054-0060
# Mod history:	2009-05-14 OH	Transcribed from 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 2021112-061
#	16:27 JULY 14, 1969

# Page 54

# ***	CHANNEL DESCRIPTIONSF WORDS ARE ALLOCATED IN ERASABLE ASSIGNMENTS ***

#	CHANNEL 1	IDENTICAL TO COMPUTER REGISTER L (0001)

#	CHANNEL 2	IDENTICAL TO COMPUTER REGISTER Q (0002)

#	CHANNEL 3	HISCALAR; INPUT CHANNEL; MOST SIGNIFICANT 14 BITS FROM 33 STAGE BINARY COUNTER. SCALE
#			FACTOR IS B23 IN CSEC, SO MAX VALUE ABOUT 23.3 HOURS AND LEAST SIGNIFICANT BIT 5.12 SECS.

#	CHANNEL 4	LOSCALAR; INPUT CHANNEL; NEXT MOST SIGNIFICANT 14 BITS FROM THE 33 STAGE BINARY COUNTER
#			ASSOCIATED WITH CHANNEL 3. SCALE FACTOR IS B9 IN  CSEC. SO MAX VAL IS 5.12 SEC AND LEAST
#			SIGNIFICANT BIT IS 1/3200 SEC. SCALE FACTOR OF D.P. WORD WITH CHANNEL 3 IS B23 CSEC.

#	CHANNEL 5	PYJETS; OUTPUT CHANNEL; PITCH RCS JET CONTROL.   (REACTION CONTROL SYSTEM) USES BITS 1-8.

#	CHANNEL 6	ROLLJETS; OUTPUT CHANNEL; ROLL RCS JET CONTROL.   (REACTION CONTROL SYSTEM) USES BIT 1-8.

#	CHANNEL 7	SUPERBNK; OUTPUT CHANNEL; NOT RESET BY RESTART;   FIXED EXTENSION BITS USED TO SELECT THE
#			APPROPRIATE FIXED MEMORY BANK IF FBANK IS 30 OCTAL OR MORE. USES BITS 5-7.

#	CHANNEL 10	OUT0; OUTPUT CHANNEL; REGISTER USED TO TRANSMIT    LATCHING-RELAY DRIVING INFORMATION FOR
#			THE DISPLAY SYSTEM.  BITS 15-12 ARE SET TO THE ROW NUMBER (1-14 OCTAL) OF THE RELAY TO BE
#			CHANGED AND BITS 11-1 CONTAIN THE REQUIRED SETTINGS FOR THE RELAYS IN THE ROW.

#	CHANNEL 11	DSALMOUT; OUTPUT CHANNEL; REGISTER WHOSE BITS ARE USED FOR ENGINE ON-OFF CONTROL AND TO
#			DRIVE INDIVIDUAL INDICATORS OF THE DISPLAY SYSTEM. BITS 1-7 ARE A RELAYS.
#
#	  BIT 1		ISS WARNING
#	  BIT 2		LIGHT COMPUTER ACTIVITY LAMP
#	  BIT 3		LIGHT UPLINK ACTIVITY LAMP
#	  BIT 4		LIGHT TEMP CAUTION LAMP
#	  BIT 5		LIGHT KEYBOARD RELEASE LAMP
#	  BIT 6		FLASH VERB AND NOUN LAMPS
#	  BIT 7		LIGHT OPERATOR ERROR LAMP
# Page 55
#	  BIT 8		SPARE
#	  BIT 9		TEST CONNECTOR OUTBIT
#	  BIT 10	CAUTION RESET
#	  BIT 11	SPARE
#	  BIT 12	SPARE
#	  BIT 13	ENGINE ON
#	  BIT 14	ENGINE OFF
#	  BIT 15	SPARE

#	CHANNEL 12	CHAN12; OUTPUT CHANNEL; BITS USED TO DRIVE NAVIGATION AND SPAECRAFT HARDWARE
#
#	  BIT 1		ZERO RR CDU; CDU'S GIVE RRADAR INFORMATION FOR LM
#	  BIT 2		ENABLE CDU RADAR ERROR COUNTERS
#	  BIT 3		NOT USED
#	  BIT 4		COARSE ALIGN ENABLE OF IMU
#	  BIT 5		ZERO IMU CDU'S
#	  BIT 6		ENABLE IMU ERROR COUNTER, CDU ERROR COUNTER.
#	  BIT 7		SPARE
#	  BIT 8		DISPLAY INERTIAL DATA
#	  BIT 9		-PITCH GIMBAL TRIM (BELL MOTION) DESCENT ENGINE
#	  BIT 10	+PITCH GIMBAL TRIM (BELL MOTION) DESCENT ENGINE
#	  BIT 11	-ROLL  GIMBAL TRIM (BELL MOTION) DESCENT ENGINE
#	  BIT 12	+ROLL  GIMBAL TRIM (BELL MOTION) DESCENT ENGINE
#	  BIT 13	LR POSITION 2 COMMAND
#	  BIT 14	ENABLE RENDESVOUS RADAR LOCK-ON;AUTO ANGLE TRACK'G
#	  BIT 15	ISS TURN ON DELAY COMPLETE

# Page 56
#	CHANNEL 13	CHAN13; OUTPUT CHANNEL.
#
#	  BIT 1		RADAR C		PROPER SETTING OF THE A,B,C MATRIX
#	  BIT 2		RADAR B		SELECTS CERTAIN RADAR
#	  BIT 3		RADAR A		PARAMETERS TO BE READ.
#	  BIT 4		RADAR ACTIVITY
#	  BIT 5		NOT USED (CONNECTS AN ALTERNATE INPUT TO UPLINK)
#	  BIT 6		BLOCK INPUTS TO UPLINK CELL
#	  BIT 7		DOWNLINK TELEMETRY WORD ORDER CODE BIT
#	  BIT 8		RHC COUNTER ENABLE (READ HAND CONTROLLER ANGLES)
#	  BIT 9		START RHC READ INTO COUNTERS IF BIT 8 SET
#	  BIT 10	TEST ALARMS, TEST DSKY LIGHTS
#	  BIT 11	ENABLE STANDBY
#	  BIT 12	RESET TRAP 31-A		ALWAYS APPEAR TO BE SET TO 0
#	  BIT 13	RESET TRAP 31-B		ALWAYS APPEAR TO BE SET TO 0
#	  BIT 14	RESET TRAP 32		ALWAYS APPEAR TO BE SET TO 0
#	  BIT 15	ENABLE T6 RUPT

#	CHANNEL 14	CHAN14; OUTPUT CHANNEL; USED TO CONTROL COMPUTER  COUNTER CELLS (CDU,GYRO,SPACECRAFT FUNC.
#
#	  BIT 1		OUTLINK ACTIVITY (NOT USED)
#	  BIT 2		ALTITUDE RATE OR ALTITIDE SELECTOR
#	  BIT 3		ALTITUDE METER ACTIVITY
#	  BIT 4		THRUST DRIVE ACTIVITY FOR DESCENT ENGINE
#	  BIT 5		SPARE
#	  BIT 6		GYRO ENABLE POWER FOR PULSES
#	  BIT 7		GYRO SELECT B		PAIR OF BITS IDENTIFIES AXIS OF -
#	  BIT 8		GYRO SELECT A		GYRO SYSTEM TO BE TORQUED.
#	  BIT 9		GYRO TORQUING COMMAND IN NEGATIVE DIRECTION
# Page 57
#	  BIT 10	GYRO ACTIVITY
#	  BIT 11	DRIVE CDU S
#	  BIT 12	DRIVE CDU T
#	  BIT 13	DRIVE CDU Z
#	  BIT 14	DRIVE CDU Y
#	  BIT 15	DRIVE CDU X

#	CHANNEL 15	MNKEYIN; INPUT CHANNEL;KEY CODE INPUT FROM KEYBOARD OF DSKY, SENSED BY PROGRAM WHEN
#			PROGRAM INTERRUPT #5 IS RECEIVED. USES BITS 5-1

#	CHANNEL 16	NAVKEYIN; INPUT CHANNEL; OPTICS MARK INFORMATION AND NAVIGA ION PANEL DSKY (CM) OR THRUST
#			CONTROL (LM) SENSED BY PROGRAM WHEN PROGRAM INTER-RUPT #6 IS RECEIVED. USES BITS 3-7 ONLY.
#
#	  BIT 1		NOT ASSIGNED
#	  BIT 2		NOT ASSIGNED
#	  BIT 3		OPTICS X-AXIS MARK SIGNAL FOR ALIGN OPTICAL TSCOPE
#	  BIT 4		OPTICS Y-AXIS MARK SIGNAL FOR AOT
#	  BIT 5		OPTICS MARK REJECT SIGNAL
#	  BIT 6		DESCENT+ ; CREW DESIRED SLOWING RATE OF DESCENT
#	  BIT 7		DESCENT- ; CREW DESIRED SPEEDING UP RATE OF D'CENT

# NOTE: ALL BITS IN CHANNELS 30-33 ARE INVERTED AS SENSED BY THE  PROGRAM, SO THAT A VALUE OF ZERO MEANS
# THAT THE INDICATED SIGNAL IS PRESENT.

#	CHANNEL 30	INPUT CHANNEL
#
#	  BIT 1		ABORT WITH DESCENT STAGE
#	  BIT 2		   UNUSED
#	  BIT 3		ENGINE ARMED SIGNAL
#	  BIT 4		ABORT WITH ASCENT ENGINE STAGE
#	  BIT 5		AUTO THROTTLE; COMPUTER CONTROL OF DESCENT ENGINE
# Page 58
#	  BIT 6		DISPLAY INERTIAL DATA
#	  BIT 7		RR CDU FAIL
#	  BIT 8		SPARE
#	  BIT 9		IMU OPERATE WITH NO MALFUNCTION
#	  BIT 10	LM COMPUTER (NOT AGS) HAS CONTROL OF LM
#	  BIT 11	IMU CAGE COMMAND TO DRIVE IMU GIMBAL ANGLES TO 0.
#	  BIT 12	IMU CDU FAIL (MALFUNCTION OF IMU CDU,S)
#	  BIT 13	IMU FAIL (MALFUNCTION OF IMU STABILIZATION LOOPS)
#	  BIT 14	ISS TURN ON REQUESTED
#	  BIT 15	TEMPERATURE OF STABLE MEMBER WITHIN DESIGN LIMITS

#	CHANNEL 31	INPUT CHANNEL; BITS ASSOCIATED WITH THE ATTITUDE  CONTROLLER, TRANSLATIONAL CONTROLLER,
#			AND SPACECRAFT ATTITUDE CONTROL; USED BY RCS DAP
#
#	  BIT 1		ROTATION (BY RHC) COMMANDED IN POSITIVE PITCH DIRECTION; MUST BE IN MINIMUM IMPULSE MODE.
#			ALSO POSITIVE ELEVATION CHANGE FOR LANDING POINT  DESIGNATOR
#	  BIT 2		AS BIT 1 EXCEPT NEGATIVE PITCH AND ELEVATION
#	  BIT 3		ROTATION (BY RHC) COMMANDED IN POSITIVE YAW DIRECTION; MUST BE IN MINIMUM IMPULSE MODE.
#	  BIT 4		AS BIT 3 EXCEPT NEGATIVE YAW
#	  BIT 5		ROTATION (BY RHC) COMMANDED IN POSITIVE ROLL DIRECTION; MUST BE IN MINIMUM IMPULSE MODE.
#			ALSO POSITIVE AZIMUTH CHANGE FOR LANDING POINT DESIGNATOR
#	  BIT 6		AS BIT 5 EXCEPT NEGATIVE ROLL AND AZIMUTH
#	  BIT 7		TRANSLATION IN +X DIRECTION COMMANDED BY THC
#	  BIT 8		TRANSLATION IN -X DIRECTION COMMANDED BY THC
#	  BIT 9		TRANSLATION IN +Y DIRECTION COMMANDED BY THC
#	  BIT 10	TRANSLATION IN -Y DIRECTION COMMANDED BY THC
#	  BIT 11	TRANSLATION IN +Z DIRECTION COMMANDED BY THC
#	  BIT 12	TRANSLATION IN -Z DIRECTION COMMANDED BY THC
# Page 59
#	  BIT 13	ATTITUDE HOLD MODE ON SCS MODE CONTROL SWITCH
#	  BIT 14	AUTO STABILIZATION OF ATTITUDE ON SCS MODE SWITCH
#	  BIT 15	ATTITUDE CONTROL OUT OF DETENT (RHC NOT IN NEUTRAL

#	CHANNEL 32	   INPUT CHANNEL.
#
#	  BIT 1		   THRUSTERS 2 & 4 DISABLED BY CREW
#	  BIT 2		   THRUSTERS 5 & 8 DISABLED BY CREW
#	  BIT 3		   THRUSTERS 1 & 3 DISABLED BY CREW
#	  BIT 4		   THRUSTERS 6 & 7 DISABLED BY CREW
#	  BIT 5		   THRUSTERS 14 & 16 DISABLED BY CREW
#	  BIT 6		   THRUSTERS 13 & 15 DISABLED BY CREW
#	  BIT 7		   THRUSTERS 9 & 12 DISABLED BY CREW
#	  BIT 8		   THRUSTERS 10 & 11 DISABLED BY CREW
#	  BIT 9		   DESCENT ENGINE GIMBALS DISABLED BY CREW
#	  BIT 10	   APPARENT DESCENT ENGINE GIMBAL FAILURE
#	  BIT 14	INDICATES PROCEED KEY IS DEPRESSED

#	CHANNEL 33	CHAN33; INPUT CHANNEL; FOR HARDWARE STATUS AND COMMAND INFORMATION. BITS 15-11 ARE FLIP-
#			FLOP BITS RESET BY A CHANNEL "WRITE" COMMAND THAT ARE RESET BY A RESTART & BY T4RUPT LOOP.
#
#	  BIT 1		SPARE
#	  BIT 2		RR AUTO-POWER ON
#	  BIT 3		RR RANGE LOW SCALE
#	  BIT 4		RR DATA GOOD
#	  BIT 5		LR RANGE DATA GOOD
#	  BIT 6		LR POS1
#	  BIT 7		LR POS2
# Page 60
#	  BIT 8		LR VEL DATA GOOD
#	  BIT 9		LR RANGE LOW SCALE
#	  BIT 10	BLOCK UPLINK INPUT
#	  BIT 11	UPLINK TOO FAST
#	  BIT 12	DOWNLINK TOO FAST
#	  BIT 13	PIPA FAIL
#	  BIT 14	WARNING OF REPEATED ALARMS: RESTART,COUNTER FAIL, VOLTAGE FAIL,AND SCALAR DOUBLE.
#	  BIT 15	LGC OSCILLATOR STOPPED

#	CHANNEL 34	DNT M1; OUTPUT CHANNEL; DOWNLINK 1  FIRST OF TWO WORDS SERIALIZATION.
#	CHANNEL 35	DNT M2; OUTPUT CHANNEL DOWNLINK 2 SOCOND OF TWO   WORDS SERIALIZATION.

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