KALCMANU_STEERING.agc
### FILE="Main.annotation"
## Copyright: Public domain.
## Filename: KALCMANU_STEERING.agc
## Purpose: A section of Luminary revision 116.
## It is part of the source code for the Lunar Module's (LM)
## Apollo Guidance Computer (AGC) for Apollo 12.
## This file is intended to be a faithful transcription, except
## that the code format has been changed to conform to the
## requirements of the yaYUL assembler rather than the
## original YUL assembler.
## Reference: pp. 366-370
## Assembler: yaYUL
## Contact: Ron Burkey <info@sandroid.org>.
## Website: www.ibiblio.org/apollo/index.html
## Mod history: 2017-01-22 MAS Created from Luminary 99.
## 2017-03-07 RSB Transcribed, and then proofed comment-text using
## 3-way diff vs Luminary 99 and Luminary 131.
## (Admittedly, the former is more for detecting errors
## in Luminary 99 than the other way around.)
## 2017-03-17 RSB Comment-text fixes identified in diff'ing
## Luminary 99 vs Comanche 55.
## Page 366
# GENERATION OF STEERING COMMANDS FOR DIGITAL AUTOPILOT FREE FALL MANEUVERS
# NEW COMMANDS WILL BE GENERATED EVERY ONE SECOND DURING THE MANEUVER
EBANK= TTEMP
NEWDELHI TC BANKCALL # CHECK FOR AUTO STABILIZATION
CADR ISITAUTO # ONLY
CCS A
TCF NOGO -2
NEWANGL TC INTPRET
AXC,1 AXC,2
MIS # COMPUTE THE NEW MATRIX FROM S/C TO
KEL # STABLE MEMBER AXES
CALL
MXM3
VLOAD STADR
STOVL MIS +12D # CALCULATE NEW DESIRED CDU ANGLES
STADR
STOVL MIS +6D
STADR
STORE MIS
AXC,1 CALL
MIS
DCMTOCDU # PICK UP THE NEW CDU ANGLES FROM MATRIX
RTB
V1STO2S
STORE NCDU # NEW CDU ANGLES
BONCLR EXIT
CALCMAN2
MANUSTAT # TO START MANEUVER
CAF TWO # +0 OTHERWISE
INCRDCDU TS SPNDX
INDEX SPNDX
CA BCDU # INITIAL CDU ANGLES
EXTEND # OR PREVIOUS DESIRED CDU ANGLES
INDEX SPNDX
MSU NCDU
EXTEND
SETLOC KALCMON1
BANK
MP DT/TAU
CCS A # CONVERT TO 2S COMPLEMENT
AD ONE
TCF +2
COM
INDEX SPNDX
TS DELDCDU # ANGLE INCREMENTS TO BE ADDED TO
INDEX SPNDX # CDUXD, CDUYD, CDUZD EVERY TENTH SECOND
## Page 367
CA NCDU # BY LEM DAP
INDEX SPNDX
XCH BCDU
INDEX SPNDX
TS CDUXD
CCS SPNDX
TCF INCRDCDU # LOOP FOR THREE AXES
RELINT
# COMPARE PRESENT TIME WITH TIME TO TERMINATE MANEUVER
TMANUCHK TC TIMECHK
TCF CONTMANU
CAF ONE
MANUSTAL INHINT # END MAJOR PART OF MANEUVER WITHIN 1 SEC
TC WAITLIST # UNDER WAITLIST CALL TO MANUSTOP
EBANK= TTEMP
2CADR MANUSTOP
RELINT
TCF ENDOFJOB
TIMECHK EXTEND
DCS TIME2
DXCH TTEMP
EXTEND
DCA TM
DAS TTEMP
CCS TTEMP
TC Q
TCF +2
TCF 2NDRETRN
CCS TTEMP +1
TC Q
TCF MANUOFF
COM
MANUOFF AD ONESEK +1
EXTEND
BZMF 2NDRETRN
INCR Q
2NDRETRN INCR Q
TC Q
DT/TAU DEC .1
MANUSTAT EXIT # INITIALIZATION ROUTINE
EXTEND # FOR AUTOMATIC MANEUVERS
DCA TIME2
## Page 368
DAS TM # TM+T0 MANEUVER COMPLETION TIME
EXTEND
DCS ONESEK
DAS TM # (TM+T0)-1
INHINT
CAF TWO
RATEBIAS TS KSPNDX
DOUBLE
TS KDPNDX
INDEX A
CA BRATE
INDEX KSPNDX # STORE MANEUVER RATE IN
TS OMEGAPD # OMEGAPD, OMEGAQD, OMEGARD
EXTEND
BZMF +2 # COMPUTE ATTITUDE ERROR
COM # OFFSET = (WX)ABS(WX)/2AJX
EXTEND # WHERE AJX= 2-JET ACCELERATION
MP BIASCALE # = -1/16
EXTEND
INDEX KDPNDX
MP BRATE
EXTEND
INDEX KSPNDX
DV 1JACC # = AJX $ 90 DEG/SEC-SEC
INDEX KSPNDX
TS DELPEROR # $ 180 DEG
CCS KSPNDX
TCF RATEBIAS
CA TIME1
AD ONESEK +1
XCH NEXTIME
TCF INCRDCDU -1
ONESEK DEC 0
DEC 100
BIASCALE OCT 75777 # = -1/16
CONTMANU CS TIME1 # RESET FOR NEXT DCDU UPDATE
AD NEXTIME
CCS A
AD ONE
TCF MANUCALL
AD NEGMAX
COM
MANUCALL INHINT # CALL FOR NEXT UPDATE VIA WAITLIST
TC WAITLIST
EBANK= TTEMP
2CADR UPDTCALL
## Page 369
CAF ONESEK +1 # INCREMENT TIME FOR NEXT UPDATE
ADS NEXTIME
TCF ENDOFJOB
UPDTCALL CAF PRIO26 # SATELLITE PROGRAM TO CALL FOR UPDATE
TC FINDVAC # OF STEERING COMMANDS
EBANK= TTEMP
2CADR NEWDELHI
TC TASKOVER
## Page 370
# ROUTINE FOR TERMINATING AUTOMATIC MANEUVERS
MANUSTOP CAF ZERO # ZERO MANEUVER RATES
TS DELDCDU2
TS OMEGARD
TS DELREROR
TS DELDCDU1
TS OMEGAQD
TS DELQEROR
CA CPSI # SET DESIRED GIMBAL ANGLES TO
TS CDUZD # DESIRED FINAL GIMBAL ANGLES
CA CTHETA
TS CDUYD
ENDROLL CA CPHI # NO FINAL YAW
TS CDUXD
CAF ZERO
TS OMEGAPD # I.E. MANEUVER DID NOT GO THRU
TS DELDCDU # GIMBAL LOCK ORIGINALLY
TS DELPEROR
GOODMANU CA ATTPRIO # RESTORE USERS PRIO
TS NEWPRIO
CA ZERO # ZERO ATTCADR
DXCH ATTCADR
TC SPVAC # RETURN TO USER
TC TASKOVER
