https://github.com/virtualagc/virtualagc
Tip revision: 4e5d304eb7cd5589b924ffb8b423b6f15511b35d authored by Ron Burkey on 20 October 2018, 17:47:00 UTC
The sample Block I AGC program TRIVIUM, found at the very end of one of
The sample Block I AGC program TRIVIUM, found at the very end of one of
Tip revision: 4e5d304
SPS_BACK-UP_RCS_CONTROL.agc
### FILE="Main.annotation"
## Copyright: Public domain.
## Filename: SPS_BACK-UP_RCS_CONTROL.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. 1497-1500
## 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.
## 2017-01-23 RRB Updated for Luminary 116.
## 2017-03-14 RSB Proofed comment text via 3-way diff vs
## Luminary 99 and 131.
## Page 1497
# PROGRAM NAME: SPSRCS
# AUTHOR: EDGAR M. OSHIKA (AC ELECTRONICS)
# MODIFIED: TO RETURN TO ALL AXES VIA Q BY P.S.WEISSMAN, OCT 7, 1968
# MODIFIED TO IMPROVE BENDING STABILITY BY G. KALAN,FEB.14, 1969
# FUNCTIONAL DESCRIPTION:
# THIS PROGRAM CONTROLS THE FIRING OF ALL RCS JETS IN THE DOCKED CONFIGURATION ACCORDING TO THE FOLLOWING PHASE
# PLANE LOGIC.
# 1. JET SENSE TEST (SPSRCS)
# IF JETS ARE FIRING NEGATIVELY,SET OLDSENSE NEGATIVE AND CONTINUE
# IF JETS ARE FIRING POSITIVELY,SET OLDSENSE POSITIVE AND CONTINUE
# IF JETS ARE NOT FIRING,SET OLDSENSE TO ZERO AND GO TO OUTER RATE LIMIT TEST
# 2. RATE DEAD BAND TEST
# IF JETS ARE FIRING NEGATIVELY AND RATE IS GREATER THAN TARGET RATE, LEAVE
# JETS ON AND GO TO INHIBITION LOGIC. OTHERWISE, CONTINUE.
# IF JETS ARE FIRING POSITIVELY AND RATE IS LESS THAN TARGET RATE, LEAVE
# JETS ON AND GO TO INHIBITION LOGIC. OTHERWISE, CONTINUE.
# 3. OUTER RATE LIMIT TEST (SPSSTART)
# IF MAGNITUDE OF EDOT IS GREATER THAN 1.73 DEG/SEC SET JET FIRING TIME
# TO REDUCE RATE AND GO TO INHIBITION LOGIC. OTHERWISE, CONTINUE.
# 4. COAST ZONE TEST
# IF STATE (E,EDOT) IS BELOW LINE E + 4 X EDOT > -1.4 DEG AND EDOT IS LESS THAN 1.30 DEG/SEC SET JET TIME POSI-
# TIVE AND CONTINUE. OTHERWISE,SET JET FIRING TIME TO ZERO AND CONTINUE.
# IF STATE IS ABOVE LINE E + 4 X EDOT > +1.4 DEG AND EDOT IS GREATER THAN -1.30 DEG/SEC, SET JET TIME NEGATIVE
# AND CONTINUE. OTHERWISE,SET JET FIRING TIME TO ZERO AND CONTINUE.
# 5. INHIBITION LOGIC
# IF OLDSENSE IS NON-ZERO:
# A) RETURN IF JET TIME HAS SAME SIGN AS OLDSENSE
# B) SET INHIBITION COUNTER*AND RETURN IF JET TIME IS ZERO
# C) SET INHIBITION COUNTER,*SET JET TIME TO ZERO AND RETURN IF SIGN
# OF JET TIME IS OPPOSITE TO THAT OF OLDSENSE
# IF OLDSENSE IS ZERO:
# A) RETURN IF INHIBITION COUNTER IS NOT POSITIVE
# B) SET JET TIME TO ZERO AND RETURN IF INHIBITION COUNTER IS POSITIVE
# *NOTE: INHIBITION COUNTERS CAN BE SET TO 4 OR 10 FOR THE P, AND UV AXES,
# RESPECTIVELY, IN SPSRCS. THEY ARE DECREMENTED BY ONE AT THE BEGINNING OF
## Page 1498
# EACH DAP PASS.
# THE MINIMUM PULSE WIDTH OF THIS CONTROLLER IS DETERMINED BY THE REPETITION RATE AT WHICH THIS ROUTINE IS CALLED
# AND IS NOMINALLY 100 MS FOR ALL AXES IN DRIFTING FLIGHT. DURING POWERED FLIGHT THE MINIMUM IS 100 MS FOR THE
# P AXIS AND 200 MS FOR THE CONTROL OF THE U AND V AXES.
# CALLING SEQUENCE:
# INHINT
# TC IBNKCALL
# CADR SPSRCS
# EXIT:
# TC Q
# ALARM/ABORT MODE: NONE
# SUBROUTINES CALLED: NONE
# INPUT: E,EDOT
# TJP, TJV, TJU TJ MUST NOT BE NEGATIVE ZERO
# OUTPUT: TJP, TJV, TJU
BANK 21
SETLOC DAPS4
BANK
COUNT* $$/DAPBU
EBANK= TJU
RATELIM2 OCT 00632 # 1.125 DEG/SEC
POSTHRST CA HALF
NDX AXISCTR
TS TJU
CCS OLDSENSE
TCF POSCHECK # JETS FIRING POSITIVELY
TCF CTRCHECK # JETS OFF. CHECK INHIBITION CTR
NEGCHECK INDEX AXISCTR # JETS FIRING NEGATIVELY
CS TJU
CCS A
TC Q # RETURN
TCF +2
TCF +1 # JETS COMMANDED OFF.SET CTR AND RETURN
SETCTR INDEX AXISCTR # JET FIRING REVERSAL COMMANDED. SET CTR,
CA UTIME # SET JET TIME TO ZERO, AND RETURN
## Page 1499
INDEX AXISCTR
TS UJETCTR
ZAPTJ CA ZERO
INDEX AXISCTR
TS TJU
TC Q
POSCHECK INDEX AXISCTR
CA TJU
TCF NEGCHECK +2
CTRCHECK INDEX AXISCTR # CHECK JET INHIBITION COUNTER
CCS UJETCTR
TCF +2
TC Q # CTR IS NOT POSITIVE. RETURN
TCF ZAPTJ # CTR IS POSITIVE.INHIBIT FIRINGS
TC Q # CTR IS NOT POSITIVE.RETURN
OCT 00004
UTIME OCT 00012
OCT 00012
OLDSENSE EQUALS DAPTREG1
NEGFIRE CS ONE # JETS FIRING NEGATIVELY
TS OLDSENSE
CA EDOT
TCF +4
PLUSFIRE CA ONE
TS OLDSENSE
CS EDOT # RATE DEAD BAND TEST
LXCH A
CS DAPBOOLS # IF DRIFTBIT = 1, USE ZERO TARGET RATE
MASK DRIFTBIT # IF DRIFTBIT = 0, USE 0.10 RATE TARGET
CCS A
CA RATEDB1
AD L
EXTEND
BZMF SPSSTART
TCF POSTHRST +3
SPSRCS INDEX AXISCTR # JET SENSE TEST
CCS TJU
TCF PLUSFIRE # JETS FIRING POSITIVELY
TCF +2
TCF NEGFIRE # JETS FIRING NEGATIVELY
TS OLDSENSE # JETS OFF
SPSSTART CA EDOT # OUTER RATE LIMIT TEST
EXTEND
MP RATELIM1
CCS A
TCF NEGTHRST # OUTER RATE LIMIT EXCEEDED
TCF +2
TCF POSTHRST # OUTER RATE LIMIT EXCEEDED
CA EDOT # COAST ZONE TEST
## Page 1500
AD E
EXTEND
MP DKDB # PAD LOADED DEADBAND. FRESHSTART: 1.4 DEG
EXTEND
BZF TJZERO
EXTEND
BZMF +7
CA EDOT
AD RATELIM2
EXTEND
BZMF TJZERO
NEGTHRST CS HALF
TCF POSTHRST +1
+7 CS RATELIM2
AD EDOT
EXTEND
BZMF POSTHRST
TJZERO CA ZERO
TCF POSTHRST +1
RATELIM1 = CALLCODE # = 00032, CORRESPONDING TO 1.73 DEG/SEC
RATEDB1 = TBUILDFX # = 00045, CORRESPONDS TO 0.101 DEG/SEC
