Pre-launch Review
TVCEXECUTIVE
Scanned pages: 945-950
# Copyright: Public domain.# Filename: TVCEXECUTIVE.agc# Purpose: Part of the source code for Colossus 2A, AKA Comanche 055.# It is part of the source code for the Command Module's (CM)# Apollo Guidance Computer (AGC), for Apollo 11.# Assembler: yaYUL# Contact: Ron Burkey <info@sandroid.org>.# Website: www.ibiblio.org/apollo.# Pages: 945-950# Mod history: 2009-05-12 RSB Adapted from the Colossus249/ file of the# same name, using Comanche055 page images.# 2009-05-20 RSB Corrections: CAE -> CAF in one place.# 2009-05-21 RSB In 1SHOTCHK, a CAF SEVEN was corrected to# CAF SIX.## 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 055 of AGC program Comanche by NASA# 2021113-051. 10:28 APR. 1, 1969## This AGC program shall also be referred to as# Colossus 2A
# Page 945# PROGRAM NAME.... TVCEXECUTIVE, CONSISTING OF TVCEXEC, NEEDLEUP, VARGAINS# 1SHOTCHK, REPCHEK, CG.CORR, COPYCYCLES, ETC.# LOG SECTION...TVCEXECUTIVE SUBROUTINE...DAPCSM# MODIFIED BY SCHLUNDT 21 OCTOBER 1968# FUNCTIONAL DESCRIPTION....## *A SELF-PERPETUATING WAITLIST TASK AT 1/2 SECOND INTERVALS WHICH:# PREPARES THE ROLL DAP WITH OGA (CDUX)# PREPARES THE ROLL FDAI NEEDLE (FLY-TO OGA ERROR)# PREPARES THE ROLL PHASE PLANE OGAERR (FLY-FROM OGA ERROR)# PREPARES THE TVC ROLLDAP TASK WAITLIST CALL (3 CS DELAY)# UPDATES THE NEEDLES DISPLAY# UPDATES VEHICLE MASS AND CALLS MASSPROP TO UPDATE INERTIA DATA# UPDATES PITCH, YAW, AND ROLL DAP GAINS FROM MASSPROP DATA# PERFORMS ONE-SHOT CORRECTION FOR TMC LOOP 0-3 SEC AFTER IGNITION# PERFORMS REPETITIVE UPDATES FOR TMC LOOP AFTER THE ONE-SHOT CORR.## CALLING SEQUENCE....## *TVCEXEC CALLED AS A WAITLIST TASK, IN PARTICULAR BY TVCINIT4 AND BY# ITSELF, BOTH AT 1/2 SECOND INTERVALS## NORMAL EXIT MODE.... TASKOVER## ALARM OR ABORT EXIT MODES.... NONE## SUBROUTINES CALLED....NEEDLER, S40.15, MASSPROP, TASKOVER, IBNKCALL## OTHER INTERFACES....## *TVCRESTART PACKAGE FOR RESTARTS# *PITCHDAP, YAWDAP FOR VARIABLE GAINS AND ENGINE TRIM ANGLES# ERASABLE INITIALIZATION REQUIRED....## *SEE TVCDAPON....TVCINIT4# *VARK AND 1/CONACC (S40.15 OF TVCINITIALIZE)# *PAD LOAD EREPFRAC# *BITS 15,14 OF FLAGWRD6 (T5 BITS)# *TVCEXPHS FOR RESTARTS# *ENGINE-ON BIT (11.13) FOR RESTARTS# *CDUX, OGAD## OUTPUT....## *ROLL DAP OGANOW, FDAI NEEDLE (AK), AND PHASE PLANE OGAERR# *VARIABLE GAINS FOR PITCH/YAW AND ROLL TVC DAPS# *SINGLE-SHOT AND REPETITIVE CORRECTIONS TO ENGINE TRIM ANGLES# PACTOFF AND YACTOFF## DEBRIS.... MUCH, BUT SHAREABLE WITH RCS/ENTRY, ALL IN EBANK6
# Page 946 BANK 16 SETLOC DAPROLL BANK EBANK= BZERO COUNT* $$/TVCX
TVCEXEC CS FLAGWRD6 # CHECK FOR TERMINATION (BITS 15,14 READ MASK OCT60000 # 10 FROM TVCDAPON TO RCSDAPON) EXTEND BZMF TVCEXFIN # TERMINATE
CAF .5SEC # W.L. CALL TO PERPETUATE TVCEXEC TC WAITLIST EBANK= BZERO 2CADR TVCEXEC
ROLLPREP CAE CDUX # UPDATE ROLL LADDERS (NO NEED TO RESTART- XCH OGANOW # PROTECT, SINCE ROLL DAPS RE-START) XCH OGAPAST
CAE OGAD # PREPARE ROLL FDAI NEEDLE WITH FLY-TO EXTEND # ERROR (COMMAND - MEASURED) MSU OGANOW TS AK # FLY-TO OGA ERROR, SC.AT B-1 REVS
EXTEND # PREPARE ROLL DAP PHASE PLANE OGAERR MP -BIT14 TS OGAERR # PHASE-PLANE (FLY-FROM) OGAERROR, # SC.AT B+0 REVS
CAF THREE # SET UP ROLL DAP TASK (ALLOW SOME TIME) TC WAITLIST EBANK= BZERO 2CADR ROLLDAP
NEEDLEUP TC IBNKCALL # DO A NEEDLES UPDATE (RETURNS AFTER CADR) CADR NEEDLER # (NEEDLES RESTARTS ITSELF)
VARGAINS CAF BIT13 # CHECK ENGINE-ON BIT TO INHIBIT VARIABLE EXTEND # GAINS AND MASS IF ENGINE OFF RAND DSALMOUT # CHANNEL 11 CCS A TCF +4 # ON , SO OK TO UPDATE GAINS AND MASS +5 CAF TWO # OFF, SO BYPASS MASS/GAIN UPDATES, TS TVCEXPHS # ALSO ENTRY FROM CCS BELOW WITH TCF 1SHOTCHK # VCNTR = -0 (V97 R40 ENGFAIL) CCS VCNTR # TEST FOR GAIN OF UPDATE TIME TCF +4 # NOT YET# Page 947 TCF GAINCHNG # NOW TCF +0 # NOT USED TCF VARGAINS +5 # NO, LOTHRUST (S40.8 R40)
+4 TS VCNTRTMP # PROTECT VCNTR AND CAE CSMMASS # CSMMASS DURING AN IMPULSIVE BURN TS MASSTMP TCF EXECCOPY
GAINCHNG TC IBNKCALL # UPDATE IXX, IAVG, IAVG/TLX CADR FIXCW # MASSPROP ENTRY (ALREADY INITIALIZED) TC IBNKCALL # UPDATE 1/CONACC, VARK CADR S40.15 # (S40.15 IS IN TVCINITIALIZE) CS TENMDOT # UPDATE MASS FOR NEXT 10 SEC. OF BURN AD CSMMASS TS MASSTMP # KG B+16
CAF NINETEEN # RESET THE VARIABLE-GAIN UPDATE COUNTER TS VCNTRTMP
EXECCOPY INCR TVCEXPHS # RESTART-PROTECT THE COPYCYCLE (1)
CAE MASSTMP # CSMMASS KG B+16 TS CSMMASS
CAE VCNTRTMP # VCNTR TS VCNTR TS V97VCNTR # FOR ENGFAIL (R41) MASS UPDATES AT SPSOFF
INCR TVCEXPHS # COPYCYCLE OVER (2)
1SHOTCHK CCS CNTR # CHECK TIME FOR ONE-SHOT OR REPCORR TCF +4 # NOT YET TCF 1SHOTOK # NOW TCF REPCHEK # ONE-SHOT OVER, ON TO REPCORR TCF 1SHOTOK # NOW (ONE-SHOT ONLY, NO REPCORR)
+4 TS CNTRTMP # COUNT DOWN CAF SIX # SET UP TVCEXPHS FOR ENTRY AT CNTRCOPY TS TVCEXPHS TCF CNTRCOPY
REPCHEK CAE REPFRAC # CHECK FOR REPETITIVE UPDATES EXTEND BZMF TVCEXFIN # NO, OVER-AND-OUT TS TEMPDAP +1 # YES, SET UP CORRECTION FRACTION CAF FOUR # SET UP TVCEXPHS FOR ENTRY AT CORSETUP TS TVCEXPHS TCF CORSETUP# Page 9481SHOTOK CAF BIT13 # CHECK ENGINE-ON BIT, NOT PERMITTING EXTEND # ONE-SHOT DURING ENGINE-SHUTDOWN RAND DSALMOUT CCS A TCF +2 # ONE-SHOT OK TCF TVCEXFIN # NO, TERMINATE
INCR TVCEXPHS # (3)
# RSB 2009. The following instruction was previously "CAE FCORFRAC", but FCORFRAC# is not in erasable memory as implied by the use of CAE. I've accordingly changed# it to CAF instead to indicate fixed memory.TEMPSET CAF FCORFRAC # SET UP CORRECTION FRACTION TS TEMPDAP +1
INCR TVCEXPHS # ENTRY FROM REPCHECK AT NEXT LOCATION (4)
CORSETUP CAE DAPDATR1 # CHECK FOR LEM-OFF/ON MASK BIT13 # (NOTE, SHOWS LEM-OFF) EXTEND BZF +2 # LEM IS ON, PICK UP TEMPDAP+1 CAE TEMPDAP +1 # LEM IS OFF, PICK UP 2(TEMPDAP+1) AD TEMPDAP +1 TS TEMPDAP # CG.CORR USES TEMPDAP
CAF NEGONE # SET UP FOR CNTR = -1 (ONE-SHOT DONE) TS CNTRTMP # (COPYCYCLE AT .CNTRCOPY. )
CG.CORR EXTEND # PITCH TMC LOOP DCA PDELOFF DXCH PACTTMP EXTEND DCS PDELOFF DDOUBL DDOUBL DXCH TTMP1 EXTEND DCA DELPBAR DDOUBL DDOUBL DAS TTMP1 EXTEND DCA TTMP1 EXTEND MP TEMPDAP DAS PACTTMP
EXTEND # YAW TMC LOOP DCA YDELOFF DXCH YACTTMP EXTEND DCS YDELOFF DDOUBL# Page 949 DDOUBL DXCH TTMP1 EXTEND DCA DELYBAR DDOUBL DDOUBL DAS TTMP1 EXTEND DCA TTMP1 EXTEND MP TEMPDAP DAS YACTTMP
CORCOPY INCR TVCEXPHS # RESTART PROTECT THE COPYCYCLE (5)
EXTEND # TRIM-ESTIMATES, AND DCA PACTTMP TS PACTOFF # TRIMS DXCH PDELOFF
EXTEND DCA YACTTMP TS YACTOFF DXCH YDELOFF
INCR TVCEXPHS # ENTRY FROM 1SHOTCHK AT NEXT LOCATION (6)
CNTRCOPY CAE CNTRTMP # UPDATE CNTR (RESTARTS OK, FOLLOWS CPYCY) TS CNTR
TVCEXFIN CAF ZERO # RESET TVCEXPHS TS TVCEXPHS TCF TASKOVER # TVCEXECUTIVE FINISHED
FCORFRAC OCT 10000 # ONE-SHOT CORRECTION FRACTION
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