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
IMU_COMPENSATION_PACKAGE.agc
### FILE="Main.annotation"
## Copyright: Public domain.
## Filename: IMU_COMPENSATION_PACKAGE.agc
## Purpose: A section of Sunburst revision 37, or Shepatin revision 0.
## It is part of an early development version of the software
## for Apollo Guidance Computer (AGC) on the unmanned Lunar
## Module (LM) flight Apollo 5. Sunburst 37 was the program
## upon which Don Eyles's offline development program Shepatin
## was based; the listing herein transcribed was actually for
## the equivalent revision 0 of Shepatin.
## 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. 802-811
## Assembler: yaYUL
## Contact: Ron Burkey <info@sandroid.org>.
## Website: www.ibiblio.org/apollo/index.html
## Mod history: 2017-05-24 MAS Created from Sunburst 120.
## 2017-06-14 HG Transcribed
## 2017-06-15 HG Fix operand CA -> CS
## 2017-06-23 RSB Proofed comment text with
## octopus/ProoferComments.
## Page 802
BANK 12
EBANK= NBDX
# PROGRAM DESCRIPTION- IMU COMPENSATION (LEM) DATE- 30 AUG 66
# MOD NO- 0 LOG SECTION- IMU COMPENSATION PACKAGE
# MOD BY- GILBERT ASSEMBLY- SUNBURST REVISION 13
# FUNCTIONAL DESCRIPTION
# THE IMU COMPENSATION PACKAGE IS DESIGNED TO COMPENSATE FOR PIPA BIAS AND SCALE FACTOR ERROR AND AT THE
# SAME TIME ACCUMULATE GYRO TORQUING COMMANDS NECESSARY TO COMPENSATE FOR THE ASSOCIATED BIAS AND ACCELERATION-
# CAUSED GYRO DRIFTS. 1/PIPA MUST BE CALLED AT LEAST EVERY 2.55 SECONDS DUE TO SCALING CONSIDERATIONS.
# SPECIFICALLY, THE CORRECTION IS
# PIPA = (1 + SCALE FACTOR ERROR)PIPA - (BIAS)(DELTAT)
# C I
# WHERE PIPA IS THE COMPENSATED DATA OBTAINED FROM THE SAMPLED DATA PIPA
# C I
# THE COMPENSATED DATA IS THEN USED TO COMPUTE THE IRIG TORQUING NECESSARY TO CANCEL THE NBD, ADIA, AND ADSRA
# GYRO COEFFICIENTS.
# SPECIFICALLY, THE COMPUTATIONS ARE
# XIRIG -(ADIAX)(PIPAX ) + (ADSRAX)(PIPAY ) - (NBDX)(DELTAT)
# C C
# YIRIG -(ADIAY)(PIPAY ) + (ADSRAY)(PIPAZ ) - (NBDY)(DELTAT)
# C C
# ZIRIG -(ADIAZ)(PIPAZ ) - (ADSRAZ)(PIPAY ) + (NBDZ)(DELTAT)
# C C
# THIS COMPENSATION IS SUMMED INTO THE GCOMP REGISTERS AND WHEN THE MAGNITUDE OF ANY IRIG COMMAND EXCEEDS 2
# PULSES, THE COMMANDS ARE SENT TO THE GYROS.
# DURING FREE-FALL PHASES OF A FLIGHT NBDX, NBDY, AND NBDZ ARE THE ONLY RELEVANT COEFFICIENTS. THESE BIAS TERMS
# WILL BE INTEGRATED BY ROUTINE NBDONLY APPROXIMATELY EVERY 81.93 SECONDS FOLLOWING AN EXECUTIVE CALL BY THE DUMMY
# TASK OF THE WAITLIST PROGRAM. NBDONLY IS ENABLED WHEN BIT 15 OF FLAGWRD2 IS SET TO INDICATE FREE-FALL. DURING
# THIS TIME 1/PIPA IS NOT CALLED.
# LASTBIAS IS CALLED VIA EXECUTIVE WHEN MAKING THE TRANSITION FROM FREE-FALL TO A PIPA READING MODE. THE NBD TERMS
# ARE COMPENSATED FOR FROM THE LAST NBDONLY CALL UP TO PIPA ZEROING. PREREAD WILL THEN ENABLE 1/PIPA AT ITS
# REGULAR INTERVAL. THE DRIFT FLAG MUST BE DOWN JUST PRIOR TO LASTBIAS. GYROCOMPASS NEVER CALLS LASTBIAS.
# SCALING CONSIDERATIONS
# UNITS MAX. VALUE INTERNAL UNITS AND SCALING
# PIPA BIAS (CM)/(SEC)(SEC) 3.125 (PIPA PULSES)/(CS) X 2(-5)
# PIPA SCALE FACTOR P.P.M. 1953.125 (PPM) X 2(-9)
# NBD MERU 128.74604 (GYRO PULSES)/(CS) X 2(-5)
# ADIA (MERU)/(G) 630.36633 (GYRO PULSES)/(PIPA PULSE) X 2(-6)
# ADSRA (MERU)/(G) 630.36633 (GYRO PULSES)/(PIPA PULSE) X 2(-6)
## Page 803
# CONVERSION TABLE
# 1 PIPA PULSE = 1.00 (CM)/(SEC) 1 ERU = 7.29209817 X 10(-5) (RAD)/(SEC)
# 1 ERU = 15.04104488 (ARCSEC)/(SEC) 1 (CM)/(SEC)(SEC) = .01 (PIPA PULSES)/(CS)
# 1 GYRO PULSE = .61798096 ARCSEC 1 MERU = .00024272592 (GYRO PULSES)/(CS)
# 1 G = 979.24 (CM)/(SEC)(SEC) (AMR) 1 (MERU)/(G) = .000024787174 (GYRO PULSES)/(PIPA PULSE)
# REFERENCES
# AGC PROGRAMMING MEMO NO. 12, I.S.S. MEMO NO. 247, I.S.S. MEMO NO. 328, I.S.S. MEMO NO. 339
# CALLING SEQUENCE
# L TC BANKCALL
# L+1 CADR 1/PIPA
# L+2 RETURNS HERE
# NORMAL EXIT MODES
# AT L+2 OF CALLING SEQUENCE
# ALARM OR ABORT MODES
# ENDOFJOB
# ERASABLE INITIALIZATION REQUIRED (CONSECUTIVE LOCATIONS)
# PBIASX PIPAX BIAS
# PIPASCFX PIPAX SCALE FACTOR ERROR
# PBIASY PIPAY BIAS
# PIPASCFY PIPAY SCALE FACTOR ERROR
# PBIASZ PIPAZ BIAS
# PIPASCFZ PIPAZ SCALE FACTOR ERROR
# NBDX X IRIG BIAS DRIFT
# NBDY Y IRIG BIAS DRIFT
# NBDZ Z IRIG BIAS DRIFT
# ADIAX IRIG ACCELERATION SENSITIVE DRIFT ALONG THE X INPUT AXIS
# ADIAY IRIG ACCELERATION SENSITIVE DRIFT ALONG THE Y INPUT AXIS
# ADIAZ IRIG ACCELERATION SENSITIVE DRIFT ALONG THE Z INPUT AXIS
# ADSRAX IRIG ACCELERATION SENSITIVE DRIFT ALONG THE X SPIN REFERENCE AXIS
# ADSRAY IRIG ACCELERATION SENSITIVE DRIFT ALONG THE Y SPIN REFERENCE AXIS
# ADSRAZ IRIG ACCELERATION SENSITIVE DRIFT ALONG THE Z SPIN REFERENCE AXIS
# GCOMP GYRO COMPENSATION PULSES (SET = ZERO FOR 1ST PASS)
# INPUT
# 1/PIPADT - DELTA TIME SCALED AT (CS) X 2(+8)
# DELVX, DELVY, DELVZ - PIPA READINGS IN THE MAJOR PARTS - MINOR PARTS IRRELEVANT
# OUTPUT
# DELVX, DELVY, DELVZ - PIPA COUNTS SCALED 2(+14) COMPENSATED FOR PIPA BIAS AND SCALE FACTOR ERROR
# GCOMP - 3 DP LOCATIONS CONTAINING GYRO PULSES TO COMPENSATE FOR NBD, ADIA, AND ADSRA COEFFICIENTS
# DEBRIS
# CENTRALS - A,L,Q
# OTHER - BUF - BUF +2, VBUF - VBUF +2, GCOMPSW
## Page 804
1/PIPA CAF LGCOMP # SAVE EBANK OF CALLING PROGRAM
XCH EBANK
TS MODE
CCS GCOMPSW # BYPASS IF GCOMPSW NEGATIVE
TCF +3
TCF +2
TCF IRIG1 # RETURN
1/PIPA1 CAF FOUR # PIPAZ, PIPAY, PIPAX
TS BUF +2
INDEX A
CA DELVX # CONTAINS PREVIOUS PIPA READING
TS VBUF # TEMPORARY - MINOR PARTS IRRELEVANT
INDEX BUF +2
CS PIPABIAS # (PIPA PULSES)/(CS) X 2(-5) *
EXTEND
MP 1/PIPADT # (CS) X 2(+8) NOW (PIPA PULSES) X 2(+3)*
EXTEND # *
MP BIT4 # SCALE 2(-3) SHIFT LEFT 3 *
LXCH VBUF +1 #(PIPA PULSES) X 2(0) FRACTIONAL PULSE*
INDEX BUF +2
CA PIPASCF # (P.P.M.) X 2(-9)
EXTEND
MP VBUF # (PIPA PULSES) X 2(+14)
LXCH VBUF +2 # SAVE FOR FRACTIONAL COMPUTATION
EXTEND
MP BIT6 # SCALE 2(+9) NOW PIPA PULSES X 2(+14)
DAS VBUF # (PIPAI) - (NBD)(DELTAT) + HI(PIPAI)(SFE)
CA VBUF +2 # NOW MINOR PART
EXTEND
MP BIT6 # SCALE 2(+9) SHIFT RIGHT 9
TS L
CAF ZERO
DAS VBUF # (PIPAI) - (NBD)(DELTAT) + (PIPAI)(SFE)
EXTEND
DCA VBUF # RESTORE COMPENSATED PIPA READING
INDEX BUF +2
DXCH DELVX
CCS BUF +2 # PIPAZ, PIPAY, PIPAX
AD NEG1
TCF 1/PIPA1 +1
NOOP # LESS THAN ZERO IMPOSSIBLE
## Page 805
IRIGCOMP TS GCOMPSW # INDICATE COMMANDS 2 PULSES OR LESS
TS BUF # INDEX COUNTER - IRIGX, IRIGY, IRIGZ
IRIGX EXTEND
DCS DELVX # (PIPA PULSES) X 2(+14)
DXCH MPAC
CA ADIAX # (GYRO PULSES)/(PIPA PULSE) X 2(-6) *
TC GCOMPSUB # -(ADIAX)(PIPAX) (GYRO PULSES) X 2(+14)
EXTEND
DCS DELVY # (PIPA PULSES) X 2(+14)
DXCH MPAC
CS ADSRAX # (GYRO PULSES)/(PIPA PULSE) X 2(-6) *
TC GCOMPSUB # +(ADSRAX)(PIPAY) (GYRO PULSES) X 2(+14)
CS NBDX # (GYRO PULSES)/(CS) X 2(-5)
TC DRIFSTUB # -(NBDX)(DELTAT) (GYRO PULSES) X 2(+14)
IRIGY EXTEND
DCS DELVY # (PIPA PULSES) X 2(+14)
DXCH MPAC
CA ADIAY # (GYRO PULSES)/(PIPA PULSE) X 2(-6) *
TC GCOMPSUB # -(ADIAY)(PIPAY) (GYRO PULSES) X 2(+14)
EXTEND
DCS DELVZ # (PIPA PULSES) X 2(+14)
DXCH MPAC
CS ADSRAY # (GYRO PULSES)/(PIPA PULSE) X 2(-6) *
TC GCOMPSUB # +(ADSRAY)(PIPAZ) (GYRO PULSES) X 2(+14)
CS NBDY # (GYRO PULSES)/(CS) X 2(-5)
TC DRIFSTUB # -(NBDY)(DELTAT) (GYRO PULSES) X 2(+14)
IRIGZ EXTEND
DCS DELVY # (PIPA PULSES) X 2(+14)
DXCH MPAC
CA ADSRAZ # (GYRO PULSES)/(PIPA PULSE) X 2(-6) *
TC GCOMPSUB # -(ADSRAZ)(PIPAY) (GYRO PULSES) X 2(+14)
EXTEND
DCS DELVZ # (PIPA PULSES) X 2(+14)
DXCH MPAC
CA ADIAZ # (GYRO PULSES)/(PIPA PULSE) X 2(-6) *
TC GCOMPSUB # -(ADIAZ)(PIPAZ) (GYRO PULSES) X 2(+14)
CA NBDZ # (GYRO PULSES)/(CS) X 2(-5)
TC DRIFSTUB # +(NBDZ)(DELTAT) (GYRO PULSES) X 2(+14)
## Page 806
CCS GCOMPSW # ARE GYRO COMMANDS GREATER THAN 2 PULSES
TCF +2 # YES
TCF IRIG1 # NO
INHINT
CAF PRIO35 # SEND OUT GYRO TORQUING COMMANDS
TC NOVAC
EBANK= NBDX
2CADR 1/GYRO
RELINT
IRIG1 CA MODE # SET EBANK FOR RETURN
TS EBANK
TCF SWRETURN
GCOMPSUB XCH MPAC # ADIA OR ADSRA COEFFICIENT ARRIVES IN A
EXTEND # C(MPAC) = (PIPA PULSES) X 2(+14)
MP MPAC # (GYRO PULSES)/(PIPA PULSE) X 2(-6) *
DXCH VBUF # NOW = (GYRO PULSES) X 2(+8) *
CA MPAC +1 # MINOR PART PIPA PULSES
EXTEND
MP MPAC # ADIA OR ADSRA
TS L
CAF ZERO
DAS VBUF # NOW = (GYRO PULSES) X 2(+8) *
CA VBUF # PARTIAL RESULT - MAJOR
EXTEND
MP BIT9 # SCALE 2(+6) SHIFT RIGHT 6 *
INDEX BUF # RESULT = (GYRO PULSES) X 2(+14)
DAS GCOMP # HI(ADIA)(PIPAI) OR HI(ADSRA)(PIPAI)
CA VBUF +1 # PARTIAL RESULT - MINOR
EXTEND
MP BIT9 # SCALE 2(+6) SHIFT RIGHT 6 *
TS L
CAF ZERO
INDEX BUF # RESULT = (GYRO PULSES) X 2(+14)
DAS GCOMP # (ADIA)(PIPAI) OR (ADSRA)(PIPAI)
TC Q
## Page 807
DRIFSTUB EXTEND
QXCH BUF +1
EXTEND # C(A) = NBD (GYRO PULSES)/(CS) X 2(-5)
MP 1/PIPADT # (CS) X 2(+8) NOW (GYRO PULSES) X 2(+3)
LXCH MPAC +1 # SAVE FOR FRACTIONAL COMPENSATION
EXTEND
MP BIT4 # SCALE 2(+11) SHIFT RIGHT 11
INDEX BUF
DAS GCOMP # HI(NBD)(DELTAT) (GYRO PULSES) X 2(+14)
CA MPAC +1 # NOW MINOR PART
EXTEND
MP BIT4 # SCALE 2(+11) SHIFT RIGHT 11
TS L
CAF ZERO
INDEX BUF # ADD IN FRACTIONAL COMPENSATION
DAS GCOMP # (NBD)(DELTAT) (GYRO PULSES) X 2(+14)
DRFTSUB2 CAF TWO # PIPAX, PIPAY, PIPAZ
AD BUF
XCH BUF
INDEX A
CCS GCOMP # ARE GYRO COMMANDS 1 PULSE OR GREATER
TCF +2 # YES
TC BUF +1 # NO
MASK COMPCHK # DEC -1
CCS A # ARE GYRO COMMANDS GREATER THAN 2 PULSES
TS GCOMPSW # YES - SET GCOMPSW POSITIVE
TC BUF +1 # NO
## Page 808
1/GYRO CAF FOUR # PIPAZ, PIPAY, PIPAX
TS BUF
INDEX BUF # SCALE GYRO COMMANDS FOR IMUPULSE
CA GCOMP +1 # FRACTIONAL PULSES
EXTEND
MP BIT8 # SHIFT RIGHT 7
INDEX BUF
TS GCOMP +1 # FRACTIONAL PULSES SCALED
CAF ZERO # SET GCOMP = 0 FOR DAS INSTRUCTION
INDEX BUF
XCH GCOMP # GYRO PULSES
EXTEND
MP BIT8 # SHIFT RIGHT 7
INDEX BUF
DAS GCOMP # ADD THESE TO FRACTIONAL PULSES ABOVE
CCS BUF # PIPAZ, PIPAY, PIPAX
AD NEG1
TCF 1/GYRO +1
LGCOMP ECADR GCOMP # LESS THAN ZERO IMPOSSIBLE
CAF LGCOMP
TC BANKCALL
CADR IMUPULSE # CALL GYRO TORQUING ROUTINE
TC BANKCALL
CADR IMUSTALL # WAIT FOR PULSES TO GET OUT
TCF ENDOFJOB # TEMPORARY
GCOMP1 CAF FOUR # PIPAZ, PIPAY, PIPAX
TS BUF
INDEX BUF # RESCALE
CA GCOMP +1
EXTEND
MP BIT8 # SHIFT MINOR PART LEFT 7 - MAJOR PART = 0
INDEX BUF
LXCH GCOMP +1 # BITS 8-14 OF MINOR PART WERE = 0
CCS BUF # PIPAZ, PIPAY, PIPAX
AD NEG1
TCF GCOMP1 +1
COMPCHK DEC -1 # LESS THAN ZERO IMPOSSIBLE
TCF ENDOFJOB
## Page 809
NBDONLY CCS GCOMPSW # BYPASS IF GCOMPSW NEGATIVE
TCF +3
TCF +2
TCF ENDOFJOB
CA TIME1 # (CS) X 2(+14)
XCH 1/PIPADT # PREVIOUS TIME
COM
AD 1/PIPADT
NBD2 CCS A # CALCULATE ELAPSED TIME
AD ONE # NO TIME1 OVERFLOW
TCF NBD3 # RESTORE TIME DIFFERENCE AND JUMP
TCF +2 # TIME1 OVERFLOW
TCF ENDOFJOB # IF ELAPSED TIME = 0 (DIFFERENCE = -0)
COM # CALCULATE ABSOLUTE DIFFERENCE
AD POSMAX
NBD3 EXTEND # C(A) = DELTAT (CS) X 2(+14)
MP BIT10 # SHIFT RIGHT 5
DXCH VBUF
EXTEND
DCA VBUF
DXCH MPAC # DELTAT NOW SCALED (CS) X 2(+19)
CAF ZERO
TS GCOMPSW # INDICATE COMMANDS 2 PULSES OR LESS
TS BUF # PIPAX, PIPAY, PIPAZ
CS NBDX # (GYRO PULSES)/(CS) X 2(-5)
TC FBIASSUB # -(NBDX)(DELTAT) (GYRO PULSES) X 2(+14)
EXTEND
DCS VBUF
DXCH MPAC # DELTAT SCALED (CS) X 2(+19)
CA NBDY # (GYRO PULSES)/(CS) X 2(-5)
TC FBIASSUB # -(NBDY)(DELTAT) (GYRO PULSES) X 2(+14)
EXTEND
DCS VBUF
DXCH MPAC # DELTAT SCALED (CS) X 2(+19)
CS NBDZ # (GYRO PULSES)/(CS) X 2(-5)
TC FBIASSUB # +(NBDZ)(DELTAT) (GYRO PULSES) X 2 (+14)
CCS GCOMPSW # ARE GYRO COMMANDS GREATER THAN 2 PULSES
TCF 1/GYRO # YES
TCF ENDOFJOB # NO
## Page 810
FBIASSUB XCH Q
TS BUF +1
CA Q # NBD SCALED (GYRO PULSES)/(CS) X 2(-5)
EXTEND
MP MPAC # DELTAT SCALED (CS) X 2(+19)
INDEX BUF
DAS GCOMP # HI(NBD)(DELTAT) (GYRO PULSES) X 2(+14)
CA Q # NOW FRACTIONAL PART
EXTEND
MP MPAC +1
TS L
CAF ZERO
INDEX BUF
DAS GCOMP # (NBD)(DELTAT) (GYRO PULSES) X 2(+14)
TCF DRFTSUB2 # CHECK MAGNITUDE OF COMPENSATION
LASTBIAS CCS GCOMPSW # BYPASS IF GCOMPSW NEGATIVE
TCF +3
TCF +2
TCF ENDOFJOB
CAF PRIO31 # 2 SECONDS SCALED (CS) X 2(+14)
XCH 1/PIPADT
COM
AD PIPTIME +1 # TIME AT PIPAI = 0
TCF NBD2
GCOMPZER CAF LGCOMP # ROUTINE TO ZERO GCOMP BEFORE FIRST
XCH EBANK # CALL TO 1/PIPA
TS MODE
CAF ZERO
TS GCOMPSW
TS GCOMP
TS GCOMP +1
TS GCOMP +2
TS GCOMP +3
TS GCOMP +4
TS GCOMP +5
## Page 811
CA MODE
TS EBANK
TCF SWRETURN # RETURN TO CALLER
