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Pre-launch Review

P30 P37

Scanned pages: 614-617

P30_P37.agc
# Copyright:  Public domain.
# Filename:  P30_P37.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:  614-617
# Mod history:  2009-05-17 RSB  Adapted from the corresponding
#        Luminary131 file, using page
#        images from Luminary 1A.
#    2009-06-05 RSB  Removed 4 lines of code that shouldn't
#        have survived from Luminary 131.
#
# 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 614
# PROGRAM DESCRIPTION P30  DATE 3-6-67
#
# MOD.1 BY RAMA AIYAWAR
# FUNCTIONAL DESCRIPTION
#  ACCEPT ASTRONAUT INPUTS OF TIG.DELV(LV)
#  CALL IMU STATUS CHECK ROUTINE (R02)
#  DISPLAY TIME TO GO, APOGEE, PERIGEE, DELV(MAG), MGA AT IGN
#  REQUEST BURN PROGRAM
#
# CALLING SEQUENCE VIA JOB FROM V37
#
# EXIT VIA V37 CALL OR TO GOTOPOOH (V34E)
#
# SUBROUTINE CALLS-FLAGUP, PHASCHNG, BANKCALL, ENDOFJOB, GOFLASH, GOFLASHR
#       GOPERF3R, INTPRET, BLANKET, GOTOPOOH, R02BOTH, S30.1,
#       TIG/N35, MIDGIM, DISPMGA
#
# ERASABLE INITIALIZATION- STATE VECTOR
#
# OUTPUT-RINIT, VINIT, +MGA, VTIG, RTIG, DELVSIN, DELVSAB, DELVSLV, HAPO,
#   HPER, TTOGO
#
# DEBRIS- A,L, MPAC, PUSHLIST


    BANK  32
    SETLOC  P30S
    BANK
    EBANK=  +MGA
    COUNT*  $$/P30
P30    TC  UPFLAG    # SET UPDATE FLAG
    ADRES  UPDATFLG
    TC  UPFLAG    # SET TRACK FLAG
    ADRES  TRACKFLG


P30N33    CAF  V06N33    # T OF IGN
    TC  VNPOOH    # RETURNS ON PROCEED, POOH ON TERMINATE


    CAF  V06N81    # DISPLAY DELTA V (LV)
    TC  VNPOOH    #     REDISPLAY ON RECYCLE


    TC  DOWNFLAG  # RESET UPDATE FLAG
    ADRES  UPDATFLG
    TC  INTPRET
    CALL
      S30.1
    SET  EXIT
      UPDATFLG
PARAM30    CAF  V06N42    # DISPLAY APOGEE,PERIGEE ,DELTA V
    TC  VNPOOH
# Page 615


    TC  INTPRET
    SETGO
      XDELVFLG  # FOR P40'S: EXTERNAL DELTA-V GUIDANCE.
      REVN1645  # TRKMKCNT, T60, +MGA  DISPLAY


V06N33    VN  0633
V06N42    VN  0642


# Page 616
# PROGRAM DESCRIPTION S30.1  DATE 9NOV66
# MOD NO 1      LOG SECTION P30,P37
# MOD BY RAMA AIYAWAR **
# FUNCTIONAL DESCRIPTION
#  BASED ON STORED TARGET PARAMETERS(R OF IGNITION(RTIG),V OF
#  IGNITION(VTIG),TIME OF IGNITION (TIG)),COMPUTE PERIGEE ALTITUDE
#  APOGEE ALTITUDE AND DELTAV REQUIRED(DELVSIN).
# CALLING SEQUENCE
#  L  CALL
#  L+1    s30.1
# NORMAL EXIT MODE
#  AT L+2 OR CALLING SEQUENCE (GOTO L+2)
# SUBROUTINES CALLED
#  LEMPREC
#  PERIAPO
# ALARM OR ABORT EXIT MODES
#  NONE
# ERASABLE INITIALIZATION REQUIRED
#  TIG    TIME OF IGNITION  DP B28CS
#  DELVSLV    SPECIFIED DELTA-V IN LOCAL VERT.
#      COORDS. OF ACTIVE VEHICLE AT
#      TIME OF IGNITION  VECTOR   B+7 METERS/CS
#
# OUTPUT
#  RTIG    POSITION AT TIG    VECTOR   B+29 METERS
#  VTIG    VELOCITY AT TIG    VECTOR   B+29 METERS/CS
#  PDL 4D    APOGEE ALTITUDE    DP   B+29 M ,  B+27 METERS.
#  HAPO    APOGEE ALTITUDE    DP   B+29 METERS
#  PDL 8D    PERIGEE ALTITUDE  DP   B+29 M ,  B+27 METERS.
#  HPER    PERIGEE ALTITUDE  DP   B+29 METERS
#  DELVSIN    SPECIFIED DELTA-V IN INTERTIAL
#      COORD. OF ACTIVE VEHICLE AT
#      TIME OF IGNITION  VECTOR   B+7 METERS/CS
#  DELVSAB    MAG. OF DELVSIN    VECTOR   B+7 METERS/CS
#
# DEBRIS  QTEMP  TEMP. ERASABLE
#    QPRET,MPAC
#    PUSHLIST


    SETLOC  P30S1
    BANK


    COUNT*  $$/S30S


S30.1    STQ  DLOAD
      QTEMP
      TIG    # TIME IGNITION SCALED AT 2(+28)CS
    STCALL  TDEC1
      LEMPREC    # ENCKE ROUTINE FOR LEM


    VLOAD  SXA,2
# Page 617
      RATT
      RTX2
    STORE  RTIG    # RADIUS VECTOR AT IGNITION TIME
    UNIT  VCOMP
    STOVL  DELVSIN    # ZRF/LV IN DELVSIN SCALED AT 2
      VATT    # VELOCITY VECTOR AT TIG, SCALED 2(7) M/CS
    STORE  VTIG
    VXV  UNIT
      RTIG
    SETPD  SXA,1
      0
      RTX1
    PUSH  VXV    # YRF/LV PDL 0  SCALED AT 2
      DELVSIN
    VSL1  PDVL
    PDVL  PDVL    # YRF/LV PDL 6 SCALED AT 2
      DELVSIN    # ZRF/LV PDL 12D SCALED AT 2
      DELVSLV
    VXM  VSL1
      0
    STORE  DELVSIN    # DELTAV IN INERT. COOR. SCALED TO B+7M/CS
    ABVAL
    STOVL  DELVSAB    # DELTA V MAG.
      RTIG    # (FOR PERIAPO)
    PDVL  VAD    # VREQUIRED = VTIG + DELVSIN (FOR PERIAPO)
      VTIG
      DELVSIN
    CALL
      PERIAPO1
    CALL
      SHIFTR1    # RESCALE IF NEEDED
    CALL      # LIMIT DISPLAY TO 9999.9 N. MI.
      MAXCHK
    STODL  HPER    # PERIGEE ALT 2(29) METERS, FOR DISPLAY
      4D
    CALL
      SHIFTR1    # RESCALE IF NEEDED
    CALL      # LIMIT DISPLAY TO 9999.9 N. MI.
      MAXCHK
    STCALL  HAPO    # APOGEE  ALT 2(29) METERS, FOR DISPLAY
      QTEMP