Pre-launch Review
TJET LAW
Scanned pages: 1460-1469
# Copyright: Public domain.# Filename: TJET_LAW.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: 1460-1469# Mod history: 2009-05-27 RSB Adapted from the corresponding# Luminary131 file, using page# images from Luminary 1A.# 2009-06-06 RSB Eliminated a stray instruction that had crept# in somehow.## 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 1460# PROGRAM DESCRIPTION# DESIGNED BY: R. D. GOSS AND P. S. WEISSMAN# CODED BY: P. S. WEISSMAN, 28 FEBRUARY 1968## TJETLAW IS CALLED AS A SUBROUTINE WHEN THE LEM IS NOT DOCKED AND THE AUTOPILOT IS IN THE AUTOMATIC OR# ATTITUDE-HOLD MODE TO CALCULATE THE JET-FIRING-TIME (TJET) REQUIRED FOR THE AXIS INDICATED BY AXISCTR:# -1 INDICATES THE P-AXIS# +0 INDICATES THE U-AXIS# +1 INDICATES THE V-AXIS# THE REGISTERS E AND EDOT CONTAIN THE APPROPRIATE ATTITUDE ERROR AND ERROR RATE AND SENSETYP SHOWS WHETHER# UNBALANCED COUPLES ARE PREFERRED. TJETLAW ALSO USES VARIOUS FUNCTIONS OF ACCELERATION AND DEADBAND WHICH ARE# COMPUTED IN THE 1/ACCONT SECTION OF 1/ACCS AND ARE STORED IN SUCH AN ORDER THAT THEY CAN BE CONVENIENTLY# ACCESSED BY INDEXING.## THE SIGN OF THE REQUIRED ROTATION IS CARRIED THROUGH TJETLAW AS ROTSENSE AND IS FINALLY APPLIED TO TJET JUST# PREVIOUS TO ITS STORAGE IN THE LOCATION CORRESPONDING TO THE AXIS (TJP, TJU, OR TJV). THE NUMBER OF JETS THAT# TJETLAW ASSUMES WILL BE USED AS INDICATED BY THE SETTING OF NUMBERT FOR THE U- OR V-AXIS. TWO JETS ARE ALWAYS# ASSUMED FOR THE P-AXIS ALTHOUGH FOUR JETS WILL BE FIRED WHEN FIREFCT IS MORE NEGATIVE THAN -4.0 DEGREES# (FIREFCT IS THE DISTANCE TO A SWITCH CURVE IN THE PHASE PLANE) AND A LONG FIRING IS CALLED FOR.## IN ORDER TO AVOID SCALING DIFFICULTIES, SIMPLE ALGORITHMS TAGGED RUFLAW1, -2 AND -3 ARE RESORTED TO WHEN THE# ERROR AND/OR ERROR RATE ARE LARGE.## CALLING SEQUENCE:# TC TJETLAW # (MUST BE IN JASK)# OR# INHINT # (MUST BE IN JASK)# TC IBNKCALL# CADR TJETLAW# RELINT## EXIT: RETURN TO Q.## INPUT:# FROM THE CALLER: E, EDOT, AXISCTR, SENSETYP, TJP, -U, -V.# FROM 1/ACCONT: 48 ERASABLES BEGINNING AT BLOCKTOP (INCLUDING FLAT, ZONE3LIM AND ACCSWU, -V).## OUTPUT:# TJP, -U OR -V, NUMBERT (DAPTEMP5), FIREFCT (DAPTEMP3).## DEBRIS:# A, L, Q, E, EDOT, DAPTEMP1-6, DAPTEMP1-4.## ALARM: NONE
BANK 17 SETLOC DAPS2 BANK EBANK= TJP# Page 1461 COUNT* $$/DAPTJ
TJETLAW EXTEND # SAVE Q FOR RETURN. QXCH HOLDQ
# SET INDEXERS TO CORRESPOND TO THE AXIS AND TO THE SIGN OF EDOT
INDEX AXISCTR # AXISDIFF(-1)=NO OF LOCATIONS BET P AND U CAF AXISDIFF # AXISDIFF(0)=0 TS ADRSDIF1 # AXISDIFF(+1)=NO OF LOCATIONS BET V AND U
CAE EDOT # IF EDOT NEGATIVE, PICK UP SET OF VALUES EXTEND # THAT ALLOW USE OF SAME CODING AS FOR BZMF NEGEDOT # POSITIVE EDOT. CAE ADRSDIF1 # SET A SECOND INDEXER WHICH MAY BE TS ADRSDIF2 # MODIFIED BY A DECISION FOR MAX JETS. CAF SENSOR # FOR POSITIVE EDOT, ROTSENSE IS TCF SETSENSE # INITIALIZED POSITIVE.
NEGEDOT CS E # IN ORDER FOR NEG EDOT CASE TO USE CODING TS E # OF POS EDOT, MUST MODIFY AS FOLLOWS: CS EDOT # 1. COMPLEMENT E AND EDOT. TS EDOT # 2. SET SENSE OF ROTATION TO NEGATIVE CAF BIT1 # (REVERSED LATER IF NECESSARY). ADS ADRSDIF1 # 3. INCREMENT INDEXERS BY ONE SO THAT TS ADRSDIF2 # THE PROPER PARAMETERS ARE ACCESSED. CS SENSORSETSENSE TS ROTSENSE
# TEST MAGNITUDE OF E (ATTITUDE ERROR, SINGLE-PRECISION, SCALED AT PI RADIANS):# IF GREATER THAN (OR EQUAL TO) PI/16 RADIANS, GO TO THE SIMPLIFIED TJET ROUTINE.# IF LESS THAN PI/16 RADIANS, RESCALE TO PI/4
CAE E # PICK UP ATTITUDE ERROR FOR THIS AXIS EXTEND MP BIT5 # SHIFT RIGHT TEN BITS: IF A-REGISTER IS CCS A # ZERO, RESCALE AND TEST EDOT. TCF RUFLAW2 TCF SCALEE TCF RUFLAW1SCALEE CAF BIT13 # ERROR IS IN L SCALED AT PI/16. RESCALE EXTEND # IT TO PI/4 AND SAVE IT. MP L TS E
# TEST MAGNITUDE OF EDOT (ERROR RATE SCALED AT PI/4 RADIANS/SECOND)# IF GREATER THAN (OR EQUAL TO) PI/32 RADIANS/SECOND, GO TO THE SIMPLIFIED TJET ROUTINE.# IF LESS THAN PI/32 RADIANS/SECOND, THEN RESCALE TO PI/32 RADIANS/SECOND.
CAE EDOT # PICK UP SINGLE-PRECISION ERROR-RATE# Page 1462 EXTEND # FOR THIS AXIS= MP BIT4 # SHIFT RIGHT ELEVEN BITS, IF THE A-REG IS EXTEND # ZERO, THEN RESCALE AND USE FINELAW. BZF SCALEDOT TCF RUFLAW3
# *** FINELAW STARTS HERE ***
SCALEDOT LXCH EDOT # EDOT IS SCALED AT PI/32 RADIANS/SECOND.
CAE EDOT # COMPUTE (EDOT)(EDOT) EXTEND SQUARE # PRODUCT SCALED AT PI(2)/2(10) RAD/SEC. EXTEND MP BIT13 # SHIFT RIGHT TWO BITS TO RESCALE TO EDOTSQ TS EDOTSQ # TO PI(2)/2(8) RAD(2)/SEC(2).
ERRTEST CCS E # DOES BIG ERROR (THREE DEG BEYOND THE AD -3DEG # DEADBAND) REQUIRE MAXIMUM JETS? TCF +2 AD -3DEG EXTEND INDEX ADRSDIF1 SU FIREDB EXTEND BZMF SENSTEST # IF NOT: ARE UNBALANCED JETS PREFERRED?MAXJETS CAF TWO # IF YES: INCREMENT ADDRESS LOCATOR AND ADS ADRSDIF2 # SET SWITCH FOR JET SELECT LOGIC TO 4. CAF FOUR # (ALWAYS DO THIS FOR P-AXIS) TCF TJCALCSENSTEST CCS SENSETYP # DOES TRANSLATION PREFER MIN JETS. TCF TJCALC # YES. USE MIN-JET PARAMETERS TCF MAXJETS # NO. GET THE MAX-JET PARAMETERS.TJCALC TS NUMBERT # SET TO +0,1,4 FOR (U,V-AXES) JET SELECT.
# BEGINNING OF TJET CALCULATIONS:
CS EDOTSQ # SCALED AT PI(2)/2(8). EXTEND INDEX ADRSDIF2 MP 1/ANET1 # .5/ACC SCALED AT 2(6)/PI SEC(2)/RADIAN. INDEX ADRSDIF1 AD FIREDB # DEADBAND SCALED AT PI/4 RADIAN. EXTEND SU E # ATTITUDE ERROR SCALED AT PI/4 RADIAN. TS FIREFCT # -E-.5(EDOTSQ)/ACC-DB AT PI/4 RADIAN. EXTEND BZMF ZON1,2,3
ZONE4,5 INDEX ADRSDIF1 CAE 1/ACOAST # .5/ACC SCALED AT 2(6)/PI WHERE# Page 1463 EXTEND # ACC = MAX(AMIN, AOS-). MP EDOTSQ # SCALED AT PI/2(8). AD E # SCALED AT PI/4 INDEX ADRSDIF1 AD COASTDB # SCALED AT PI/4 POS. FOR NEG. INTERCEPT. EXTEND # TEST E+.5(EDOTSQ)/ACC+DB AT PI/4 RADIAN. BZMF ZONE5 # IF FUNCTION NEGATIVE, FIND TJET. # IF FUNCTION POSITIVE, IN ZONE 4.
# ZONE 4 IS THE COAST REGION. HOWEVER, IF THE JETS ARE ON AND DRIVING TOWARD# A. THE AXIS WITHIN + OR - (DB + FLAT) FOR DRIFTING FLIGHT, OR# B. THE USUAL TARGET PARABOLA FOR POWERED FLIGHT# THEN THE THRUSTERS ARE KEPT ON.
ZONE4 INDEX AXISCTR # IS THE CURRENT VALUE IN TJET NON-ZERO CS TJETU # WITH SENSE OPPOSITE TO EDOT, EXTEND # (I.E., ARE JETS ON AND FIRING TOWARD MP ROTSENSE # THE DESIRABLE STATE). EXTEND BZMF COASTTJ # NO. COAST.
JETSON CCS FLAT # YES. IS THIS DRIFTING OR POWERED FLIGHT? TCF DRIFT/ON # DRIFTING. GO MAKE FURTHER TEST.
CS FIREFCT # POWERED (OR ULLAGE). CAN TARGET PARABOLA INDEX ADRSDIF1 # BE REACHED FROM THIS POINT IN THE AD AXISDIST # PHASE PLANE? EXTEND BZMF COASTTJ # NO. SET TJET = 0. TC Z123COMP # YES. CALCULATE TJET AS THOUGH IN ZONE 1 CAE FIREFCT # AFTER COMPUTING THE REQUIRED TCF ZONE1 # PARAMETERS.
DRIFT/ON INDEX ADRSDIF1 # CAN TARGET STRIP OF AXIS BE REACHED FROM CS FIREDB # THIS POINT IN THE PHASE PLANE? DOUBLE AD FIREFCT EXTEND BZMF +3COASTTJ CAF ZERO # NO. SET TJET = 0. TCF RETURNTJ
TC Z123COMP # YES. CALCULATE TJET AS THOUGH IN ZONE 2 TCF ZONE2,3 # OR 3 AFTER COMPUTING REQUIRED VALUES.
ZONE5 TS L # TEMPORARILY STORE FUNCTION IN L. CCS ROTSENSE # MODIFY ADRSDIF2 FOR ACCESSING 1/ANET2 TCF +4 # AND ACCFCTZ5, WHICH MUST BE PICKED UP TC CCSHOLE # FROM THE NEXT LOWER REGISTER IF THE CS TWO # (ACTUAL) ERROR RATE IS NEGATIVE.# Page 1464 ADS ADRSDIF2
+4 CAE L EXTEND INDEX ADRSDIF2 # TTOAXIS AND HH ARE THE PARAMETERS UPON MP ACCFCTZ5 # WHICH THE APPROXIMATIONS TO TJET ARE DDOUBL # ABASED. DDOUBL DXCH HH # DOUBLE PRECISION H SCALED AT 8 SEC(2). INDEX ADRSDIF2 CAE 1/ANET2 # SCALED AT 2(7)/PI SEC(2)/RAD. EXTEND MP EDOT # SCALED AT PI/2(5) TS TTOAXIS # SCALED AT 4 SEC.
# TEST WHETHER TJET GREATER THAN 50 MSEC.
EXTEND MP -.05AT2 # H - .05 TTOAXIS - .00125 G.T. ZERO AD HH # (SCALED AT 8 SEC(2) ). AD NEG2 EXTEND BZMF FORMULA1
# TEST WHETHER TJET GREATER THAN 150 MSEC.
CAE TTOAXIS EXTEND MP -.15AT2 # H - .15 TTOAXIS - .01125 G.T. ZERO AD HH # (SCALED AT 8 SEC(2) ) AD -.0112A8 EXTEND BZMF FORMULA2
# IF TJET GREATER THAN 150 MSEC, ASSIGN IT VALUE OF 250 MSEC, SINCE THIS# IS ENOUGH TO ASSURE NO SKIP NEXT CSP (100 MSEC).
FULLTIME CAF BIT11 # 250 MSEC SCALED AT 4 SEC.
# RETURN TO CALLING PROGRAM WITH JET TIME SCALED AS TIME6 AND SIGNED.
RETURNTJ EXTEND # ALL BRANCHES TERMINATE HERE WITH TJET MP ROTSENSE # (SCALED AT 4 SEC) IN THE ACCUMULATOR. INDEX AXISCTR # ROTSENSE APPLIES SIGN AND CHANGES SCALE. TS TJETU EXTEND INDEX AXISCTR MP ACCSWU # SET SWITCH FOR JET SELECT IF ROTATION IS CAE L EXTEND # IN A SENSE FOR WHICH 1/ACCS HAS FORCED BZMF +3 # A MAX-JET CALCULATION. CAF FOUR# Page 1465 TS NUMBERT TC HOLDQ # RETURN VIA SAVED Q.
# TJET = H/(.025 + TTOAXIS) FOR TJET LESS THAN 50 MSEC.
FORMULA1 CS -.025AT4 # .025 SEC SCALED AT 4. AD TTOAXIS # SCALED AT 4 SECONDS. DXCH HH # STORE DENOMINATOR IN FIRST WORD OF H, EXTEND # WHICH NEED NOT BE PRESERVED. PICK UP DV HH # DP H AND DIVIDE BY DENOMINATOR. EXTEND MP BIT14 # RESCALE TJET FROM 2 TO USUAL 4 SEC. TCF CHKMINTJ # CHECK THAT TJET IS NOT LESS THAN MINIMUM
# TJET = (H + .00375)/(0.1 + TTOAXIS) FOR TJET GREATER THAN 50 MSEC.
FORMULA2 EXTEND DCA .00375A8 # .00375 SEC(2) SCALED AT 8. DAS HH # STORE NUMERATOR IN DP H, WHICH NEED NOT # BE PRESERVED. CAE TTOAXIS # SCALED AT 4 SEC. AD .1AT4 # 0.1 SEC SCALED AT 4. DXCH HH # STORE DENOMINATOR IN FIRST WORD OF H, EXTEND # WHICH NEED NOT BE PRESERVED. PICK UP DV HH # DP NUMERATOR AND DIVIDE BY DENOMINATOR EXTEND MP BIT14 # RESCALE TJET FROM 2 TO USUAL 4 SEC. TCF RETURNTJ # END SUBROUTINE.
# SUBROUTINIZED COMPUTATIONS REQUIRED FOR ALL ENTRIES INTO CODING FOR ZONES 1, 2, AND 3.# REACHED BY TC FROM 3 POINTS IN TJETLAW.
Z123COMP CS ROTSENSE # USED IN RETURNTJ SECTION TO RESCALE TJET TS ROTSENSE # AS TIME6 AND GIVE IT PROPER SIGN. CAE EDOT # SCALED AT PI/2(5) RAD/SEC. EXTEND INDEX ADRSDIF2 MP 1/ANET1 # SCALED AT 2(7)/PI SEC(2)/RAD. TS TTOAXIS # STORE TIME-TO-AXIS SCALED AT 4 SECONDS. AD -TJMAX EXTEND # IS TIME TO AXIS LESS THAN 150 MSEC. BZMF +2 TCF FULLTIME # NO. FIRE JETS, DO NOT CALCULATE TJET. RETURN # YES. GO ON TO FIND TJET
ZON1,2,3 TC Z123COMP # SUBROUTINIZED PREPARATION FOR ZONE1,2,3.
# IF THE (NEG) DISTANCE BEYOND PARABOLA IS LESS THAN FLAT, USE SPECIAL# LOGIC TO ACQUIRE MINIMUM IMPULSE LIMIT CYCLE. DURING POWERED FLIGHT# Page 1466# OR ULLAGE, FLAT = 0
CAE FIREFCT # SCALED AT PI/4 RAD. AD FLAT EXTEND BZMF ZONE1 # NOT IN SPECIAL ZONES.
# FIRE FOR AXIS OR, IF CLOSE, FIRE MINIMUM IMPULSE. IF ON AXIS, COAST.
ZONE2,3 CS ZONE3LIM # HEIGHT OF MIN-IMPULSE ZONE SET BY 1/ACCS AD TTOAXIS # 35 MSEC IN DRIFTING FLIGHT EXTEND # ZERO WHEN TRYING TO ENTER GTS CONTROL. BZMF ZONE3ZONE2 CAE TTOAXIS # FIRE TO AXIS. TCF RETURNTJZONE3 CCS EDOT # CHECK IF EDOT IS ZERO. CAF BIT6 # FIRE A ONE-JET MINIMUM IMPULSE. TCF RETURNTJ # TJET = +0. TC CCSHOLE # CANNOT BE BECAUSE NEG EDOT COMPLEMENTED. TCF RETURNTJ # TJET = +0.
ZONE1 EXTEND INDEX ADRSDIF1 SU AXISDIST # SCALED AT PI/4 RAD. EXTEND INDEX ADRSDIF2 MP ACCFCTZ1 # SCALED AT 2(7)/PI SEC(2)/RAD. DDOUBL DDOUBL DXCH HH # DOUBLE PRECISION H SCALED AT 8 SEC(2).
# TEST WHETHER TOTAL TIME REQUIRED GREATER THAN 150 MSEC:# 2 2# IS .5(.150 - TTOAXIS) - H NEGATIVE (SCALED AT 8 SECONDS )
CAE TTOAXIS # TTOAXIS SCALED AT 4 SECONDS. AD -TJMAX # -.150 SECOND SCALED AT 4. EXTEND SQUARE EXTEND SU HH # HIGH WORD OF H SCALED AT 8 SEC(2). EXTEND BZMF FULLTIME # YES. NEED NOT CALCULATE TJET.
# TEST WHETHER TIME BEYOND AXIS GREATER THAN 50 MSEC TO DETERMINE WHICH APPROXIMATION TO USE.
CAE HH AD NEG2 EXTEND BZMF FORMULA3
# Page 1467# TJET = H/0.1 + TTOAXIS + .0375 FOR APPROXIMATION OVER MORE THAN 50 MSEC.
CAF .1AT2 # STORE .1 SEC SCALED AT 2 FOR DIVISION. DXCH HH # DP H SCALED AT 8 SEC(2) NEED NOT BE EXTEND # PRESERVED. DV HH # QUOTIENT SCALED AT 4 SECONDS. AD TTOAXIS # SCALED AT 4 SEC. AD .0375AT4 # .0375 SEC SCALED AT 4. TCF RETURNTJ # END COMPUTATION.
# TJET - H/.O25 + TTOAXIS FOR APPROXIMATION OVER LESS THAN 50 MSEC.
FORMULA3 CS -.025AT2 # STORE +.25 SEC SCALED AT 2 FOR DIVISION DXCH HH # PICK UP DP H AT 8, WHICH NEED NOT BE EXTEND # PRESERVED. DV HH # QUOTIENT SCALED AT 4 SECONDS. AD TTOAXIS # SCALED AT 4 SEC.
# IF COMPUTED JET TIME IS LESS THAN TJMIN, TJET IS SET TO ZERO.# MINIMUM IMPULSES REQUIRED IN ZONE 3 ARE NOT SUBJECT TO THIS CONSTRAINT, NATURALLY.
CHKMINTJ AD -TJMIN # IS COMPUTED TIME LESS THAN THE MINIMUM. EXTEND BZMF COASTTJ # YES, SET TIME TO ZERO. AD TJMIN # NO, RESTORE COMPUTED TIME. TCF RETURNTJ # END COMPUTATION.
# Page 1468# *** ROUGHLAW ***## BEFORE ENTRY TO RUFLAW:# 1. INDEXERS ADRSDIF1 AND ADRSDIF2 ARE SET ON BASIS OF AXIS, AND SIGN OF EDOT.# 2. IF EDOT WAS NEGATIVE, E AND EDOT ARE ROTATED INTO UPPER HALF-PLANE AND ROTSENSE IS MADE NEGATIVE.# 3. E IS SCALED AT PI RADIANS AND EDOT AT PI/4 RAD/SEC.# (EXCEPT THE RUFLAW3 ENTRY WHEN E IS AT PI/4)## RUFLAW1: ERROR MORE NEGATIVE THAN PI/16 RAD. FIRE TO A RATE OF 6.5 DEG/SEC (IF JET TIME EXCEEDS 20 MSEC.).# RUFLAW2: ERROR MORE POSITIVE THAN PI/16 RAD. FIRE TO AN OPPOSING RATE OF 6.5 DEG/SEC.# RUFLAW3: ERROR RATE GREATER THAN PI/32 RAD/SEC AND ERROR WITHIN BOUNDS. COAST IF BELOW FIREFCT, FIRE IF ABOVE
RUFLAW1 CS RUFRATE # DECREMENT EDOT BY .1444 RAD/SEC AT PI/4 ADS EDOT # WHICH IS THE TARGET RATE EXTEND BZMF SMALRATE # BRANCH IF RATE LESS THAN TARGET. TC RUFSETUP # REVERSE ROTSENSE AND INDICATE MAX JETS. CAE EDOT # PICK UP DESIRED RATE CHANGE.
RUFLAW12 EXTEND # COMPUTE TJET INDEX ADRSDIF2 # = (DESIRED RATE CHANGE)/(2-JET ACCEL.) MP 1/ANET1 +2 AD -1/8 # IF TJET, SCALED AT 32 SEC, EXCEEDS EXTEND # 4 SECONDS, SET TJET TO TJMAX. BZMF +2 TCF FULLTIME EXTEND BZF FULLTIME AD BIT12 # RESTORE COMPUTED TJET TO ACCUMULATOR DAS A DAS A DAS A # RESCALED TJET AT 4 SECONDS. TCF CHKMINTJ # RETURN AS FROM FINELAW.
SMALRATE TC RUFSETUP +2 # SET NUMBERT AND FIREFCT FOR MAXIMUM JETS CCS ROTSENSE CAF ONE # MODIFY INDEXER TO POINT TO 1/ANET TCF +2 # CORRESPONDING TO THE PROPER SENSE. CAF NEGONE ADS ADRSDIF2
CS EDOT # (.144 AT PI/4 - EDOT) = DESIRED RATE CHNG. TCF RUFLAW12
RUFLAW2 TC RUFSETUP # REVERSE ROTSENSE AND INDICATE MAX JETS. CAF RUFRATE AD EDOT # (.144 AT PI/4 + EDOT) = DESIRED RATE CHNG. TS A # IF OVERFLOW SKIP, FIRE FOR FULL TIME. TCF RUFLAW12 # OTHERWISE, COMPUTE JET TIME. TCF FULLTIME
# Page 1469RUFLAW3 TC RUFSETUP # EXECUTE COMMON RUFLAW SUBROUTINE. INDEX ADRSDIF1 CS FIREDB # CALCULATE DISTANCE FROM SWITCH CURVE AD E # 1/ANET1*EDOT*EDOT +E - FIREDB = 0 EXTEND # SCALED AT 4 PI RADIANS MP BIT11 XCH EDOT EXTEND SQUARE EXTEND INDEX ADRSDIF1 MP 1/ANET1 +2 AD EDOT EXTEND BZMF COASTTJ # COAST IF BELOW IT. TCF FULLTIME # FIRE FOR FULL PERIOD IF ABOVE IT.
# SUBROUTINE USED IN ALL ENTRIES TO ROUGHLAW.
RUFSETUP CS ROTSENSE # REVERSE ROTSENSE WHEN ENTER HERE. TS ROTSENSE +2 CAF FOUR # REQUIRE MAXIMUM (2) JETS IN U,V-AXES. TS NUMBERT CAF NEGMAX # SUGGEST MAXIMUM (4) JETS IN P-AXIS. TS FIREFCT TC Q
# CONSTANTS FOR TJETLAW
DEC -16 # AXISDIFF(INDEX) = NUMBER OF REGISTERSAXISDIFF DEC +0 # BETWEEN STORED 1/ACCS PARAMETERS FOR DEC 16 # THE INDEXED AXIS AND THE U-AXIS.SENSOR OCT 14400 # RATIO OF TJET SCALING WITHIN TJETLAW # (4 SEC) TO SCALING FOR T6 (10.24 SEC).-3DEG DEC -.06667 # -3.0 DEGREES SCALED AT 45.-.0112A8 DEC -.00141 # -.01125 SEC(2) SCALED AT 8..1AT4 DEC .025 # 0.1 SECOND SCALED AT 4..1AT2 DEC .05 # .1 SEC SCALED AT 2..0375AT4 DEC .00938 # .0375 SEC SCALED AT 4.-.025AT2 DEC -.0125 # -.025 SEC SCALED AT 2.-.025AT4 DEC -.00625-.05AT2 DEC -.025-.15AT2 DEC -.075.00375A8 2DEC .00375 B-3
-TJMAX DEC -.0375 # LARGEST CALCULATED TIME. .150 SEC AT 4.TJMIN DEC .005 # SMALLEST ALLOWABLE TIME. .020 SEC AT 4.-TJMIN DEC -.005RUFRATE DEC .1444 # CORRESPONDS TO TARGET RATE OF 6.5 DEG/S.