https://github.com/virtualagc/virtualagc
Tip revision: a8d66c8ae3c4d967053e2bfb4298e90182cbeff2 authored by Ron Burkey on 06 March 2024, 12:40:55 UTC
Minor tweaks associated with supporting Skylark 48.
Minor tweaks associated with supporting Skylark 48.
Tip revision: a8d66c8
AVERAGE_G_INTEGRATOR.agc
### FILE="Main.annotation"
## Copyright: Public domain.
## Filename: AVERAGE_G_INTEGRATOR.agc
## Purpose: A module for revision 0 of BURST120 (Sunburst). It
## is part of the source code for the Lunar Module's
## (LM) Apollo Guidance Computer (AGC) for Apollo 5.
## Assembler: yaYUL
## Contact: Ron Burkey <info@sandroid.org>.
## Website: www.ibiblio.org/apollo/index.html
## Mod history: 2016-09-30 RSB Created draft version.
## 2016-10-29 MAS Adapted from Colossus 237.
## 2016-10-31 RSB Typos.
## 2016-12-06 RSB Comment-proofing via octopus/ProoferComments;
## no changes were made.
## Page 842
# *************************************************************************************************************
# ROUTINE CALCRVG INTEGRATES THE EQUATIONS OF MOTION BY AVERAGING THE THRUST AND GRAVITATIONAL
# ACCELERATIONS OVER A TIME INTERVAL OF 2 SECONDS.
# FOR THE EARTH-CENTERED GRAVITATIONAL FIELD, THE PERTURBATION DUE TO OBLATENESS IS COMPUTED TO THE FIRST
# HARMONIC COEFFICIENT J.
# ROUTINE CALCRVG REQUIRES...
# 1) THRUST ACCELERATION INCREMENTS IN DELV SCALED SAME AS PIPAX,Y,Z
# 2) VN SCALED 2(+7)M/CS.
# 3) PUSHDOWN COUNTER SET TO ZERO.
# IT LEAVES RN1 UPDATED (SCALED AT 2(+24)M, VN1 (SCALED AT 2(+7)M/CS), ANDGDT1/2 (SCALED AT 2(+7)M/CS).
BANK 30
EBANK= EVEX
CALCGRAV UNIT # ENTER WITH RN AT 2(+24)M IN VAC
STORE UNITR
DOT PUSH
UNITW
DSQ DDV
DP1/10
BDSU PDDL
DP1/8TH
36D
STODL RMAG
J(RE)SQ
DDV
34D
STORE 32D
DMP
VXSC PDDL
UNITR
DMP VXSC
32D
UNITW
VAD VAD
UNITR
PDDL DDV
-MUDT
34D
VXSC STADR
STORE GDT1/2
RVQ
CALCRVG VLOAD VXSC
DELV
## Page 843
KPIP1
PUSH STQ # DV/2 TO PD SCALED AT 2(+7)M/CS
31D
VAD PUSH # (DV-OLDGDT)/2 TO PD SCALED AT 2(+7)M/CS
GDT/2
VAD VXSC
VN
2SEC(17)
VAD
RN
STCALL RN1 # TEMP STORAGE OF RN SCALED 2(+24)M
CALCGRAV
## Both VADs on the following line are circled.
VAD VAD
VAD
VN
STCALL VN1 # TEMP STORAGE OF VN SCALED 2(+7)M/CS
31D
KPIP 2DEC .1024 # SCALES DELV TO 2(+4)
KPIP1 2DEC 0.0064
DP1/8TH 2DEC 0.125
DP1/10 2DEC 0.1
J(RE)SQ 2DEC 0.060066630 B-5 # SCALED AT 2(+45)
-MUDT 2DEC* -7.9720645 E+12 B-55*
2SEC(17) 2DEC 200 B-17
DP2(-3) 2DEC 0.125
MUEARTH 2DEC 0.009063188 # 3.98603223 E14 SCALED AT 2(42)M(3)/CS(2)
MUMOON 2DEC 0.007134481 # 4.90277800 E12 SCALED AT 2(36)M(3)/CS(2)