Source Code
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These source-code files derive from a printout of Luminary 210 (Apollo 15-17
Lunar Module guidance computer program), from the personal library of
original AGC developer Don Eyles, digitally photographed at archive.org,
financially sponsored by Jim Lawton, and transcribed to source code by a
team of volunteers. This colorized, syntax-highlighted form was created
by assembling that transcribed source code. Note that the full page images
are available on the
Virtual AGC project page at archive.org, while reduced-size images
are presented at the VirtualAGC project website. Report or fix any
transcription errors at
the Virtual AGC project code repository. Notations on the program listing read, in part: GAP: ASSEMBLE REVISION 210 OF AGC PROGRAM LUMINARY BY NASA 2021112-161 17:11 MAR. 19,1971Note that the date is the date of the printout, not the date of the program revision. |
063834,000002: ## Copyright: Public domain.
063835,000003: ## Filename: TRIM_GIMBAL_CONTROL_SYSTEM.agc
063836,000004: ## Purpose: A section of Luminary revision 210.
063837,000005: ## It is part of the source code for the Lunar Module's (LM)
063838,000006: ## Apollo Guidance Computer (AGC) for Apollo 15-17.
063839,000007: ## This file is intended to be a faithful transcription, except
063840,000008: ## that the code format has been changed to conform to the
063841,000009: ## requirements of the yaYUL assembler rather than the
063842,000010: ## original YUL assembler.
063843,000011: ## Reference: pp. 1470-1482
063844,000012: ## Assembler: yaYUL
063845,000013: ## Contact: Ron Burkey <info@sandroid.org>.
063846,000014: ## Website: www.ibiblio.org/apollo/index.html
063847,000015: ## Mod history: 2016-11-17 JL Created from Luminary131 version.
063848,000016: ## 2016-12-26 RSB Comment-text proofed using ProoferComments
063849,000017: ## and corrected errors found.
063850,000018:
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Page 1470 |
063852,000020: 21,3027 BANK 21
063853,000021: 21,3027 E6,1450 EBANK= QDIFF
063854,000022: 21,2000 SETLOC DAPS4
063855,000023: 21,2000 BANK
063856,000024:
063857,000025: 21,3027 COUNT* $$/DAPGT
063858,000026:
063859,000027: # CONTROL REACHES THIS POINT UNDER EITHER OF THE FOLLOWING TWO CONDITIONS ONCE THE DESCENT ENGINE AND THE DIGITAL
063860,000028: # AUTOPILOT ARE BOTH ON:
063861,000029: # A) THE TRIM GIMBAL CONTROL LAW WAS ON DURING THE PREVIOUS Q,R-AXIS TIME5 INTERRUPT (OR THE DAPIDLER
063862,000030: # INITIALIZATION WAS SET FOR TRIM GIMBAL CONTROL AND THIS IS THE FIRST PASS), OR
063863,000031: # B) THE Q,R-AXES RCS AUTOPILOT DETERMINED THAT THE VEHICLE WAS ENTERING (OR HAD JUST ENTERED) A COAST
063864,000032: # ZONE WITH A SMALL OFFSET ANGULAR ACCELERATION.
063865,000033:
063866,000034: # GTS IS THE ENTRY TO THE GIMBAL TRIM SYSTEM FOR CONTROLLING ATTITUDE ERRORS AND RATES AS WELL AS ACCELERATIONS.
063867,000035:
063868,000036: 21,3027 37770 GTS CAF NEGONE # MAKE THE NEXT PASS THROUGH THE DAP BE
063869,000037: 21,3030 55630 TS COTROLER # THROUGH RCS CONTROL,
063870,000038: 21,3031 34742 CAF FOUR # AND ENSURE THAT IT IS NOT A SKIP.
063871,000039: 21,3032 55534 TS SKIPU
063872,000040: 21,3033 55535 TS SKIPV
063873,000041:
063874,000042: 21,3034 34743 CAF TWO
063875,000043: 21,3035 55632 TS INGTS # SET INDICATOR OF GTS CONTROL POSITIVE.
063876,000044: 21,3036 55631 TS QGIMTIMR # SET TIMERS TO 200 MSEC TO AVOID BOTH
063877,000045: 21,3037 55633 TS RGIMTIMR # RUNAWAY AND INTERFERENCE BY NULLING.
063878,000046:
063879,000047: # THE DRIVE SETTING ALGORITHM
063880,000048:
063881,000049: # DEL = SGN(OMEGA + ALPHA*ABS(ALPHA)/(2*K))
063882,000050:
063883,000051: # 2 1/2 2 3/2
063884,000052: # NEGUSUM = ERROR*K + ALPHA*(DEL*OMEGA + ALPHA /(3*K)) + DEL*K (DEL*OMEGA + ALPHA /(2*K))
063885,000053:
063886,000054: # DRIVE = -SGN(NEGUSUM)
063887,000055:
063888,000056: 21,3040 30021 CA SR # SAVE THE SR. SHIFT IT LEFT TO CORRECT
063889,000057: 21,3041 60000 AD A # FOR THE RIGHT SHIFT DUE TO EDITING.
063890,000058: 21,3042 55505 TS SAVESR
063891,000059:
063892,000060: 21,3043 34743 GTSGO+DN CAF TWO # SET INDEXER FOR R-AXIS CALCULATIONS.
063893,000061: 21,3044 13046 TCF GOQTRIMG +1
063894,000062:
063895,000063: 21,3045 34746 GOQTRIMG CAF ZERO # SET INDEXER FOR Q-AXIS CALCULATIONS
063896,000064: 21,3046 55747 TS QRCNTR
063897,000065:
063898,000066: 21,3047 51747 INDEX QRCNTR # AOS SCALED AT PI/2
063899,000067: 21,3050 31536 CA AOSQ
063900,000068: 21,3051 00006 EXTEND
063901,000069: 21,3052 74743 MP BIT2 # RESCALE AOS TO PI/4
063902,000070:
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Page 1471 |
063904,000072: 21,3053 00006 EXTEND
063905,000073: 21,3054 13060 BZF GTSQAXIS -3 # USE FULL SCALE FOR LARGER AOS ESTIMATES.
063906,000074:
063907,000075: 21,3055 50000 INDEX A
063908,000076: 21,3056 44725 CS LIMITS # LIMITS +1 CONTAINS NEGMAX.
063909,000077: 21,3057 56001 XCH L # LIMITS -1 CONTAINS POSMAX.
063910,000078:
063911,000079: 21,3060 11747 CCS QRCNTR # PICK UP RATE FOR THIS AXIS. RATE CELLS
063912,000080: 21,3061 50000 INDEX A # ARE ADJACENT, NOT SEPARATED. AT PI/4
063913,000081: 21,3062 31436 CA EDOTQ
063914,000082: 21,3063 53743 GTSQAXIS DXCH WCENTRAL
063915,000083:
063916,000084: 21,3064 51747 INDEX QRCNTR # COLLECT K FOR THIS AXIS
063917,000085: 21,3065 31504 CA KQ
063918,000086: 21,3066 55740 TS KCENTRAL
063919,000087:
063920,000088: 21,3067 00006 EXTEND # CONTROL AUTHORITY ZERO. AVOID DRIVING
063921,000089: 21,3070 13526 BZF POSDRIVE +1 # ENGINE BELL TO THE STOPS.
063922,000090:
063923,000091: 21,3071 51747 INDEX QRCNTR # QDIFF, RDIFF ARE STORED IN D.P.
063924,000092: 21,3072 31450 CAE QDIFF
063925,000093:
063926,000094: 21,3073 00006 ALGORTHM EXTEND # Q(R)DIFF IS THETA (ERROR) SCALED AT PI.
063927,000095: 21,3074 71740 MP KCENTRAL # FORM K*ERROR AT PI(2)/2(8), IN D.P.
063928,000096: 21,3075 23736 LXCH K2THETA
063929,000097: 21,3076 00006 EXTEND
063930,000098: 21,3077 74740 MP BIT5 # RESCALE TO 4*PI(2)
063931,000099: 21,3100 53737 DXCH K2THETA
063932,000100: 21,3101 00006 EXTEND
063933,000101: 21,3102 74740 MP BIT5 # FIRST TERM OF NEGUSUM IN K2THETA.
063934,000102: 21,3103 27737 ADS K2THETA +1 # NO CARRY NEEDED D.P. AT 4*PI(2)
063935,000103:
063936,000104: 21,3104 41743 CS ACENTRAL # FORM ALPHA(2)/(2*K) AT 16*PI, IN D.P.,
063937,000105: 21,3105 00006 EXTEND # LIMITING QUOTIENT TO AVOID OVERFLOW.
063938,000106: 21,3106 74727 MP BIT14 # -ALPHA/2 IN A, SCALED AT PI/4
063939,000107: 21,3107 00006 EXTEND
063940,000108: 21,3110 71743 MP ACENTRAL # -ALPHA(2)/2 IN A,L, SCALED AT PI(2)/16
063941,000109: 21,3111 61740 AD KCENTRAL
063942,000110: 21,3112 00006 EXTEND
063943,000111: 21,3113 63130 BZMF HUGEQUOT # K-ALPHA(2)/2 SHOULD BE PNZ FO DIVISION
063944,000112:
063945,000113: 21,3114 00006 EXTEND
063946,000114: 21,3115 40001 DCS A # ALPHA(2)/2 - K
063947,000115: 21,3116 61740 AD KCENTRAL
063948,000116: 21,3117 00006 EXTEND
063949,000117: 21,3120 11740 DV KCENTRAL # HIGH ORDER OF QUOTIENT.
063950,000118: 21,3121 57745 XCH A2CNTRAL
063951,000119: 21,3122 30001 CA L # SHIFT UP THE REMAINDER.
063952,000120: 21,3123 22007 LXCH 7 # ZERO LOW-ORDER DIVIDEND.
063953,000121: 21,3124 00006 EXTEND
063954,000122:
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Page 1472 |
063956,000124: 21,3125 11740 DV KCENTRAL
063957,000125: 21,3126 57746 XCH A2CNTRAL +1 # QUOTIENT STORED AT 16*PI, D.P.
063958,000126: 21,3127 13133 TCF HAVEQUOT
063959,000127:
063960,000128: 21,3130 34724 HUGEQUOT CA POSMAX
063961,000129: 21,3131 54001 TS L
063962,000130: 21,3132 53746 DXCH A2CNTRAL # LIMITED QUOTIENT STORED AT 16*PI, D.P.
063963,000131:
063964,000132: 21,3133 31742 HAVEQUOT CA WCENTRAL
063965,000133: 21,3134 00006 EXTEND
063966,000134: 21,3135 74734 MP BIT9 # RESCALE OMEGA AT 16*PI IN D.P.
063967,000135: 21,3136 53742 DXCH K2CNTRAL # LOWER WORD OVERLAYS OMEGA IN WCENTRAL
063968,000136:
063969,000137: 21,3137 00006 EXTEND
063970,000138: 21,3140 31742 DCA K2CNTRAL
063971,000139: 21,3141 53751 DXCH FUNCTION
063972,000140:
063973,000141: 21,3142 31743 CA ACENTRAL # GET ALPHA*ABS(ALPHA)/(2*K)
063974,000142: 21,3143 00006 EXTEND
063975,000143: 21,3144 63150 BZMF +4
063976,000144:
063977,000145: 21,3145 00006 EXTEND
063978,000146: 21,3146 31746 DCA A2CNTRAL
063979,000147: 21,3147 13152 TCF +3
063980,000148:
063981,000149: 21,3150 00006 EXTEND
063982,000150: 21,3151 41746 DCS A2CNTRAL
063983,000151:
063984,000152: 21,3152 21751 DAS FUNCTION # OMEGA + ALPHA*ABS(ALPHA)/2*K) AT 16*PI
063985,000153:
063986,000154: 21,3153 11750 CCS FUNCTION # DEL = +1 FOR FUNCT1 GREATER THAN ZERO.
063987,000155: 21,3154 13160 TCF POSFNCT1 # OTHERWISE DEL = -1
063988,000156: 21,3155 13157 TCF +2
063989,000157: 21,3156 13162 TCF NEGFNCT1
063990,000158:
063991,000159: 21,3157 11751 CCS FUNCTION +1 # USE LOW ORDER WORD SINCE HIGH IS ZERO
063992,000160: 21,3160 34744 POSFNCT1 CAF BIT1
063993,000161: 21,3161 13163 TCF +2
063994,000162: 21,3162 44744 NEGFNCT1 CS BIT1
063995,000163: 21,3163 55744 TS DEL
063996,000164:
063997,000165: 21,3164 11744 CCS DEL # REPLACE OMEGA BY DEL*OMEGA
063998,000166: 21,3165 13177 TCF FUNCT2 # POSITIVE DEL VALUE. PROCEED.
063999,000167: 21,3166 13170 TCF DEFUNCT
064000,000168: 21,3167 13174 TCF NEGFNCT2
064001,000169:
064002,000170: 21,3170 55741 DEFUNCT TS K2CNTRAL
064003,000171: 21,3171 55742 TS K2CNTRAL +1
064004,000172: 21,3172 13177 TCF FUNCT2
064005,000173:
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Page 1473 |
064007,000175: 21,3173 65252 NEG1/3 DEC -.33333
064008,000176:
064009,000177: 21,3174 00006 NEGFNCT2 EXTEND
064010,000178: 21,3175 41742 DCS K2CNTRAL
064011,000179: 21,3176 53742 DXCH K2CNTRAL
064012,000180:
064013,000181: 21,3177 00006 FUNCT2 EXTEND
064014,000182: 21,3200 31746 DCA A2CNTRAL
064015,000183: 21,3201 21742 DAS K2CNTRAL # DEL*OMEGA + ALPHA(2)/(2*K) AT 16*PI, D.P.
064016,000184:
064017,000185: 21,3202 31745 FUNCT3 CA A2CNTRAL
064018,000186: 21,3203 00006 EXTEND
064019,000187: 21,3204 73173 MP NEG1/3
064020,000188: 21,3205 53746 DXCH A2CNTRAL
064021,000189: 21,3206 30001 CA L
064022,000190: 21,3207 00006 EXTEND
064023,000191: 21,3210 73173 MP NEG1/3
064024,000192: 21,3211 27746 ADS A2CNTRAL +1
064025,000193: 21,3212 54001 TS L
064026,000194: 21,3213 13215 TCF +2 # A2CNTRAL NOW CONTAINS -ALPHA(2)/(6*K),
064027,000195: 21,3214 27745 ADS A2CNTRAL # SCALED AT 16*PI, IN D.P.
064028,000196:
064029,000197: 21,3215 00006 EXTEND
064030,000198: 21,3216 31742 DCA K2CNTRAL # DEL*OMEGA + ALPHA(2)/(3*K) IN A2CNTRAL,
064031,000199: 21,3217 21746 DAS A2CNTRAL # SCALED AT 16*PI, D.P.
064032,000200:
064033,000201: 21,3220 31745 CA A2CNTRAL
064034,000202: 21,3221 00006 EXTEND
064035,000203: 21,3222 71743 MP ACENTRAL
064036,000204: 21,3223 21737 DAS K2THETA
064037,000205: 21,3224 31746 CA A2CNTRAL +1
064038,000206: 21,3225 00006 EXTEND
064039,000207: 21,3226 71743 MP ACENTRAL # ACENTRAL MAY NOW BE OVERLAID.
064040,000208: 21,3227 27737 ADS K2THETA +1
064041,000209: 21,3230 54001 TS L
064042,000210: 21,3231 13233 TCF +2 # TWO TERMS OF NEGUSUM ACCUMULATED, SO FAR
064043,000211: 21,3232 27736 ADS K2THETA # SCALED AT 4*PI(2), IN D.P.
064044,000212:
064045,000213: 21,3233 31741 GETROOT CA K2CNTRAL # K*(DEL*OMEGA + ALPHA(2)/(2*K)) IS THE
064046,000214: 21,3234 00006 EXTEND # TERM FOR WHICH A SQUARE ROOT IS NEEDED.
064047,000215: 21,3235 71740 MP KCENTRAL # K AT PI/2(8)
064048,000216: 21,3236 53751 DXCH FUNCTION
064049,000217: 21,3237 31742 CA K2CNTRAL +1
064050,000218: 21,3240 00006 EXTEND
064051,000219: 21,3241 71740 MP KCENTRAL
064052,000220: 21,3242 27751 ADS FUNCTION +1
064053,000221: 21,3243 54001 TS L
064054,000222: 21,3244 13246 TCF +2
064055,000223: 21,3245 27750 ADS FUNCTION # DESIRED TERM IN FUNCTION, AT PI(2)/16
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Page 1474 |
064057,000225: 21,3246 11744 CCS DEL
064058,000226: 21,3247 13454 TCF RSTOFGTS
064059,000227: 21,3250 13516 TCF NEGUSUM
064060,000228: 21,3251 13253 TCF NEGATE
064061,000229: 21,3252 13516 TCF NEGUSUM
064062,000230:
064063,000231: 21,3253 00006 NEGATE EXTEND
064064,000232: 21,3254 41742 DCS K2CNTRAL
064065,000233: 21,3255 53742 DXCH K2CNTRAL
064066,000234: 21,3256 13454 TCF RSTOFGTS
064067,000235:
064068,000236: 16,3736 BANK 16
064069,000237: 16,3736 E6,1501 EBANK= NEGUQ
064070,000238: 16,2000 SETLOC DAPS1
064071,000239: 16,2000 BANK
064072,000240:
064073,000241: # THE WRCHN12 SUBROUTINE SETS BITS 9,10,11,12 OF CHANNEL 12 ON THE BASIS OF THE CONTENTS OF NEGUQ,NEGUR WHICH ARE
064074,000242: # THE NEGATIVES OF THE DESIRED ACCELERATION CHANGES. ACDT+C12 SETS Q(R)ACCDOT TO REFLECT THE NEW DRIVES.
064075,000243:
064076,000244: # WARNING: ACDT+C12 AND WRCHN12 MUST BE CALLED WITH INTERRUPT INHIBITED.
064077,000245:
064078,000246: 16,3736 07400 BGIM OCTAL 07400
064079,000247: 16,3737 0066 CHNL12 EQUALS ITEMP6
064080,000248: 16,3737 41501 ACDT+C12 CS NEGUQ
064081,000249: 16,3740 00006 EXTEND # GIMBAL DRIVE REQUESTS.
064082,000250: 16,3741 71507 MP ACCDOTQ
064083,000251: 16,3742 23510 LXCH QACCDOT
064084,000252: 16,3743 41503 CS NEGUR
064085,000253: 16,3744 00006 EXTEND
064086,000254: 16,3745 71511 MP ACCDOTR
064087,000255: 16,3746 23512 LXCH RACCDOT
064088,000256:
064089,000257: 16,3747 11501 CCS NEGUQ
064090,000258: 16,3750 34733 CAF BIT10
064091,000259: 16,3751 13753 TCF +2
064092,000260: 16,3752 34734 CAF BIT9
064093,000261: 16,3753 54066 TS CHNL12
064094,000262:
064095,000263: 16,3754 11503 CCS NEGUR
064096,000264: 16,3755 34731 CAF BIT12
064097,000265: 16,3756 13760 TCF +2
064098,000266: 16,3757 34732 CAF BIT11
064099,000267: 16,3760 26066 ADS CHNL12 # (STORED RESULT NOT USED AT PRESENT)
064100,000268:
064101,000269: 16,3761 43736 CS BGIM
064102,000270: 16,3762 00006 EXTEND
064103,000271: 16,3763 02012 RAND CHAN12
064104,000272: 16,3764 60066 AD CHNL12
064105,000273: 16,3765 00006 EXTEND
064106,000274: 16,3766 01012 WRITE CHAN12
064107,000275:
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Page 1475 |
064109,000277: 16,3767 44740 CS CALLGMBL # TURN OFF REQUEST FOR ACDT+C12 EXECUTION.
064110,000278: 16,3770 71774 MASK RCSFLAGS
064111,000279: 16,3771 55774 TS RCSFLAGS
064112,000280:
064113,000281: 16,3772 00002 TC Q # RETURN TO CALLER.
064114,000282:
064115,000283: 21,3257 BANK 21
064116,000284: 21,3257 E6,1450 EBANK= QDIFF
064117,000285: 21,2000 SETLOC DAPS4
064118,000286: 21,2000 BANK
064119,000287:
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Page 1476 |
064121,000289: # SUBROUTINE TIMEGMBL: MOD 0, OCTOBER 1967, CRAIG WORK
064122,000290:
064123,000291: # TIMEGMBL COMPUTES THE DRIVE TIME NEEDED FOR THE TRIM GIMBAL TO POSITION THE DESCENT ENGINE NOZZLE SO AS TO NULL
064124,000292: # THE OFFSET ANGULAR ACCELERATION ABOUT THE Q (OR R) AXIS. INSTEAD OF USING AOSQ(R), TIMEGMBL USES .4*AOSQ(R),
064125,000293: # SCALED AT PI/8. FOR EACH AXIS, THE DRIVE TIME IS COMPUTED AS ABS(ALPHA/ACCDOT). A ZERO
064126,000294: # ALPHA OR ACCDOT OR A ZERO QUOTIENT TURNS OFF THE GIMBAL DRIVE IMMEDIATELY. OTHERWISE, THE GIMBAL IS TURNED ON
064127,000295: # DRIVING IN THE CORRECT DIRECTION. THE Q(R)GIMTIMR IS SET TO TERMINATE THE DRIVE AND Q(R)ACCDOT
064128,000296: # IS STORED TO REFLECT THE NEW ACCELERATION DERIVATIVE. NEGUQ(R) WILL CONTAIN +1,+0,-1 FOR A Q(R)ACCDOT VALUE
064129,000297: # WHICH IS NEGATIVE, ZERO, OR POSITIVE.
064130,000298:
064131,000299: # INPUTS: AOSQ,AOSR, SCALED AT P1/2, AND ACCDOTQ, ACCDOTR AT PI/2(7). PI/2(7).
064132,000300:
064133,000301: # OUTPUTS: NEW GIMBAL DRIVE BITS IN CHANNEL 12,NEGUQ,NEGUR,QACCDOT AND RACCDOT, THE LAST SCALED AT PI/2(7).
064134,000302: # Q(R)GIMTIMR WILL BE SET TO TIME AND TERMINATE GIMBAL DRIVE(S)
064135,000303:
064136,000304: # DEBRIS: A,L,Q, ITEMPS 2,3,6, RUPTREG2 AND ACDT+C12 DEBRIS.
064137,000305:
064138,000306: # EXITS: VIA TC Q.
064139,000307:
064140,000308: # ALARMS, ABORTS, : NONE
064141,000309:
064142,000310: # SUBROUTINES: ACDT+C12, IBNKCALL
064143,000311:
064144,000312: # WARNING: THIS SUBROUTINE WRITES INTO CHANNEL 12 AND USES THE ITEMPS. THEREFORE IT MAY ONLY BE CALLED WITH
064145,000313: # INTERRUPT INHIBITED.
064146,000314:
064147,000315: # ERASABLE STORAGE CONFIGURATION (NEEDED BY THE INDEXING METHODS):
064148,000316:
064149,000317: # NEGUQ ERASE +2 NEGATIVE OF Q-AXIS GIMBAL DRIVE
064150,000318: # (SPWORD) EQUALS NEGUQ +1 ANY S.P. ERASABLE NUMBER, NOW THRSTCMD
064151,000319: # NEGUR EQUALS NEGUQ +2 NEGATIVE OF R-AXIS GIMBAL DRIVE
064152,000320:
064153,000321: # ACCDOTQ ERASE +2 Q-JERK TERM SCALED AT PI/2(7) RAD/SEC(3)
064154,000322: # (SPWORD) EQUALS ACCDOTQ +1 ANY S.P. ERASABLE NUMBER NOW QACCDOT
064155,000323: # ACCDOTR EQUALS ACCDOTQ +2 R-JERK TERM SCALED AT PI/2(7) RAD/SEC(3)
064156,000324: # ACCDOTQ,ACCDOTR ARE MAGNITUDES.
064157,000325: # AOSQ ERASE +4 Q-AXIS ACC.,D.P. AT PI/2 R/SEC(2)
064158,000326: # AOSR EQUALS AOSQ +2 R-AXIS ACCELERATION SCALED AT PI/2 R/S2
064159,000327:
064160,000328: 21,3257 0066 QRNDXER EQUALS ITEMP6
064161,000329: 21,3257 23146 OCT23146 OCTAL 23146 # DECIMAL .6
064162,000330: 21,3260 0063 NZACCDOT EQUALS ITEMP3
064163,000331:
064164,000332: 21,3260 34744 TIMEGMBL CAF ONE # INITIALIZE ALLOWGTS.
064165,000333: 21,3261 55502 TS ALLOWGTS
064166,000334:
064167,000335: 21,3262 34743 CAF TWO # SET UP LOOP FOR R AXIS.
064168,000336: 21,3263 22002 LXCH Q # SAVE RETURN ADDRESS.
064169,000337: 21,3264 22071 LXCH RUPTREG2
064170,000338:
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Page 1477 |
064172,000340: 21,3265 13267 TCF +2
064173,000341: 21,3266 34746 TIMQGMBL CAF ZERO # NOW DO THE Q-AXIS
064174,000342: 21,3267 54066 TS QRNDXER
064175,000343: 21,3270 50066 INDEX QRNDXER
064176,000344: 21,3271 31507 CA ACCDOTQ # ACCDOT IS PRESUMED TO BE AT PI/2(7).
064177,000345: 21,3272 00006 EXTEND
064178,000346: 21,3273 63343 BZMF TGOFFNOW # IS ACCDOT LESS THAN OR EQUAL TO 0?
064179,000347: 21,3274 54063 TS NZACCDOT # NO. STORE NON-ZERO, POSITIVE ACCDOT.
064180,000348:
064181,000349: 21,3275 50066 ALPHATRY INDEX QRNDXER
064182,000350: 21,3276 41536 CS AOSQ
064183,000351: 21,3277 00006 EXTEND
064184,000352: 21,3300 13343 BZF TGOFFNOW # IS ALPHA ZERO?
064185,000353:
064186,000354: 21,3301 54002 TS Q # SAVE A COPY OF -AOS.
064187,000355: 21,3302 00006 EXTEND # NO. RESCALE FOR TIMEGMBL USE.
064188,000356: 21,3303 73257 MP OCT23146 # OCTAL 23146 IS DECIMAL .6
064189,000357: 21,3304 60002 AD Q # -1.6*AOS AT PI/2 = -.4*AOS AT PI/8.
064190,000358: 21,3305 54001 TS L # WAS THERE OVERFLOW?
064191,000359: 21,3306 13313 TCF SETNEGU # NO. COMPUTE DRIVE TIME.
064192,000360:
064193,000361: 21,3307 40000 CS A # RECOVER -SGN(AOS) IN THE A REGISTER.
064194,000362: 21,3310 50066 INDEX QRNDXER # YES. START DRIVE WITHOUT WAITLIST.
064195,000363: 21,3311 57501 XCH NEGUQ
064196,000364: 21,3312 13347 TCF NOTALLOW # KNOCK DOWN THE ALLOWGTS FLAG.
064197,000365:
064198,000366: 21,3313 00006 SETNEGU EXTEND
064199,000367: 21,3314 63321 BZMF POSALPH
064200,000368:
064201,000369: 21,3315 40000 COM
064202,000370: 21,3316 54062 TS ITEMP2 # STORE -ABS(.4*AOS) SCALED AT PI/8.
064203,000371: 21,3317 44744 CS BIT1
064204,000372: 21,3320 13323 TCF POSALPH +2
064205,000373: 21,3321 54062 POSALPH TS ITEMP2 # STORE -ABS(.4*AOS) SCALED AT PI/8.
064206,000374: 21,3322 34744 CA BIT1
064207,000375: 21,3323 50066 +2 INDEX QRNDXER # SGN(AOS) INTO NEGU
064208,000376: 21,3324 55501 TS NEGUQ # STORE SGN(APLHA) AS NEGU
064209,000377:
064210,000378: 21,3325 30063 CA NZACCDOT
064211,000379: 21,3326 00006 EXTEND
064212,000380: 21,3327 74731 MP BIT12 # 2*ACCDOT, SCALED AT PI/8.
064213,000381: 21,3330 60062 AD ITEMP2 # -ABS(ALPHA) + 2*ACCDOT, AT PI/8.
064214,000382: 21,3331 00006 EXTEND
064215,000383: 21,3332 63347 BZMF NOTALLOW # IS DRIVE TIME MORE THAN TWO SECONDS?
064216,000384: 21,3333 40062 CS ITEMP2 # NO. COMPUTE DRIVE TIME.
064217,000385: 21,3334 00006 EXTEND # ABS(ALPHA) AT PI/8.
064218,000386: 21,3335 73370 MP OCT00240 # DECIMAL 10/1024
064219,000387: 21,3336 00006 EXTEND # QUOTIENT IS DRIVE TIME AT WAITLIST.
064220,000388: 21,3337 10063 DV NZACCDOT # ABS(ALPHA)/ACCDOT AT 2(14)/100
064221,000389:
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Page 1478 |
064223,000391: 21,3340 00006 EXTEND
064224,000392: 21,3341 13343 BZF TGOFFNOW # DRIVE TIME MUST BE GREATER THAN ZERO.
064225,000393:
064226,000394: 21,3342 13355 TCF DRIVEON
064227,000395:
064228,000396: 21,3343 34746 TGOFFNOW CAF ZERO # TURN OFF GIMBAL NOW.
064229,000397: 21,3344 50066 INDEX QRNDXER
064230,000398: 21,3345 55501 TS NEGUQ
064231,000399:
064232,000400: 21,3346 13357 TCF DONEYET
064233,000401:
064234,000402: 21,3347 36010 NOTALLOW CAF OCT31
064235,000403: 21,3350 50066 INDEX QRNDXER
064236,000404: 21,3351 55631 TS QGIMTIMR
064237,000405: 21,3352 34746 CAF ZERO # DRIVE TIME IS MORE THAN 2 SECONDS, SO
064238,000406: 21,3353 55502 TS ALLOWGTS # DO NOT PERMIT FURTHER GTS ATTITUDE-RATE
064239,000407: # CONTROL UNTIL AOSTASK APPROVES.
064240,000408: 21,3354 13357 TCF DONEYET # NO WAITLIST CALL IS MADE.
064241,000409:
064242,000410: 21,3355 50066 DRIVEON INDEX QRNDXER
064243,000411: 21,3356 55631 TS QGIMTIMR # CHOOSE Q OR R AXIS.
064244,000412:
064245,000413: 21,3357 10066 DONEYET CCS QRNDXER
064246,000414: 21,3360 13266 TCF TIMQGMBL
064247,000415:
064248,000416: 21,3361 52073 DXCH RUPTREG3 # PROTECT IBNKCALL ERASABLES. ACDT+C12
064249,000417: 21,3362 52063 DXCH ITEMP2 # LEAVES ITEMPS2,3 ALONE.
064250,000418:
064251,000419: 21,3363 04665 TC IBNKCALL # TURN OF CHANNEL BITS, SET Q(R)ACCDOTS.
064252,000420: 21,3364 35737 CADR ACDT+C12
064253,000421:
064254,000422: 21,3365 52063 DXCH ITEMP2 # RESTORE ERASABLES FOR IBNKCALL.
064255,000423: 21,3366 52073 DXCH RUPTREG3
064256,000424:
064257,000425: 21,3367 00071 TC RUPTREG2 # RETURN TO CALLER.
064258,000426:
064259,000427: 21,3370 00240 OCT00240 OCTAL 00240 # DECIMAL 10/1024
064260,000428:
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Page 1479 |
064262,000430: # THE FOLLOWING SECTION IS A CONTINUATION OF THE TRIM GIMBAL CONTROL FROM THE LAST GTS ENTRY. THE QUANTITY NEGUSUM
064263,000431: # IS COMPUTED FOR EACH AXIS (Q,R), .707*DEL*FUNCTION(3/2) + K2THETA = NEGUSUM. NEW DRIVES ARE ENTERED TO CH 12.
064264,000432:
064265,000433: # THE SUBROUTINE GTSQRT ACCEPTS A DOUBLE PRECISION VALUE IN FUNCTION, FUNCTION +1 AND RETURNS A SINGLE-PRECISION
064266,000434: # SQUARE ROOT OF THE FOURTEEN MOST SIGNIFICANT BITS OF THE ARGUMENT. ALSO, THE CELL SHFTFLAG CONTAINS A BINARY
064267,000435: # EXPONENT S, SUCH THAT THE SQUARE ROOT (RETURNED IN THE A REGISTER) MUST BE SHIFTED RIGHT (MULTIPLIED BY 2 TO THE
064268,000436: # POWER (-S)) IN ORDER TO BE THE TRUE SQUARE ROOT OF THE FOURTEEN MOST SIGNIFICANT BITS OF FUNCTION, FUNCTION +1.
064269,000437: # SQUARE ROOT ERROR IS NOT MORE THAN 2 IN THE 14TH SIGNIFICANT BIT. CELLS CLOBBERED ARE A,L,SHFTFLAG,ININDEX,
064270,000438: # HALFARG,SCRATCH,SR,FUNCTION, FUNCTION +1. GTSQRT IS CALLED BY TC GTSQRT AND RETURNS VIA TC Q OR TC FUNCTION +1.
064271,000439: # ZERO OR NEGATIVE ARGUMENTS YIELD ZERO FOR SQUARE ROOTS.
064272,000440:
064273,000441: 21,3371 11750 GTSQRT CCS FUNCTION
064274,000442: 21,3372 13410 TCF GOODARG # FUNCTION IS POSITIVE. TAKE SQUARE ROOT.
064275,000443: 21,3373 13375 TCF +2 # HIGH ORDER WORD IS ZERO. TRY THE LOWER.
064276,000444: 21,3374 13401 TCF ZEROOT # NEGATIVE. USE ZERO FOR 1/2 POWER.
064277,000445:
064278,000446: 21,3375 31751 CA FUNCTION +1
064279,000447: 21,3376 00006 EXTEND
064280,000448: 21,3377 63401 BZMF ZEROOT
064281,000449:
064282,000450: 21,3400 13404 TCF ZEROHIGH # PROCEED.
064283,000451: 21,3401 34746 ZEROOT CA ZERO
064284,000452: 21,3402 55740 TS SHFTFLAG
064285,000453: 21,3403 00002 TC Q
064286,000454:
064287,000455: 21,3404 57750 ZEROHIGH XCH FUNCTION # 14 MOST SIGNIFICANT BITS ARE IN THE
064288,000456: 21,3405 57751 XCH FUNCTION +1 # LOWER WORD. EXCHANGE THEM.
064289,000457: 21,3406 34750 CA SEVEN
064290,000458: 21,3407 13411 TCF GOODARG +1
064291,000459:
064292,000460: 21,3410 34746 GOODARG CA ZERO
064293,000461: 21,3411 55740 TS SHFTFLAG
064294,000462: 21,3412 35745 CA TWELVE # INITIALIZE THE SCALING LOOP.
064295,000463: 21,3413 55743 TS ININDEX
064296,000464: 21,3414 13423 TCF SCALLOOP
064297,000465:
064298,000466: 21,3415 31750 SCALSTRT CA FUNCTION
064299,000467: 21,3416 13437 TCF SCALDONE
064300,000468:
064301,000469: 21,3417 37767 MULBUSH CA NEG2 # IF ARG IS NOT LESS THAN 1/4, INDEX IS
064302,000470: 21,3420 27743 ADS ININDEX # ZERO, INDICATING NO SHIFT NEEDED.
064303,000471: 21,3421 00006 EXTEND # BRANCH IF ARG IS NOT LESS THAN 1/4.
064304,000472: 21,3422 63415 BZMF SCALSTRT # OTHERWISE COMPARE ARG WITH A REFERENCE
064305,000473: # WHICH IS 4 TIMES LARGER THAN THE LAST.
064306,000474: 21,3423 41750 SCALLOOP CS FUNCTION
064307,000475: 21,3424 51743 INDEX ININDEX
064308,000476: 21,3425 64726 AD BIT15 # REFERENCE MAGNITUDE LESS OR EQUAL TO 1/4
064309,000477: 21,3426 00006 EXTEND
064310,000478: 21,3427 63417 BZMF MULBUSH # IF ARG IS NOT LESS THAN REFERENCE, GO
064311,000479: # AROUND THE MULBERRY BUSH ONCE MORE.
064312,000480:
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Page 1480 |
064314,000482: 21,3430 51743 INDEX ININDEX
064315,000483: 21,3431 34726 CA BIT15 # THIS IS THE SCALE MAGNITUDE
064316,000484: 21,3432 57746 XCH HALFARG # 2**(-ININDEX) IS THE SHIFT DIVISOR.
064317,000485: 21,3433 00006 EXTEND # RESCALE ARGUMENT.
064318,000486: 21,3434 31751 DCA FUNCTION
064319,000487: 21,3435 00006 EXTEND
064320,000488: 21,3436 11746 DV HALFARG
064321,000489: # ININDEX AND SHFTFLAG PRESERVE INFO FOR
064322,000490:
064323,000491: # RESCALING AFTER ROOT PROCESS.
064324,000492: 21,3437 00006 SCALDONE EXTEND
064325,000493: 21,3440 23751 QXCH FUNCTION +1 # SAVE Q FOR RETURN
064326,000494: 21,3441 00006 EXTEND
064327,000495: 21,3442 74727 MP BIT14
064328,000496: 21,3443 55746 TS HALFARG
064329,000497: 21,3444 74730 MASK BIT13
064330,000498: 21,3445 10000 CCS A
064331,000499: 21,3446 33564 CA OCT11276
064332,000500: 21,3447 63562 AD ROOTHALF # INITIAL GUESS IS ROOT 1/2 OR POSMAX
064333,000501:
064334,000502: 21,3450 03566 TC ROOTCYCL
064335,000503: 21,3451 03566 TC ROOTCYCL
064336,000504: 21,3452 03566 TC ROOTCYCL
064337,000505:
064338,000506: 21,3453 01751 TC FUNCTION +1
064339,000507:
064340,000508: # ****************************************************************************************************************
064341,000509:
064342,000510:
064343,000511: 21,3454 03371 RSTOFGTS TC GTSQRT
064344,000512: 21,3455 57741 PRODUCT XCH K2CNTRAL
064345,000513: 21,3456 00006 EXTEND
064346,000514: 21,3457 71741 MP K2CNTRAL
064347,000515: 21,3460 53742 DXCH K2CNTRAL
064348,000516: 21,3461 00006 EXTEND # THE PRODUCT OF
064349,000517: 21,3462 70001 MP L # 1/2 2 1/2
064350,000518: 21,3463 27742 ADS K2CNTRAL +1 # K *(DEL*OMEGA + ALPHA /(2*K))
064351,000519: 21,3464 54001 TS L # AND
064352,000520: 21,3465 13467 TCF +2 # 2
064353,000521: 21,3466 27741 ADS K2CNTRAL # DEL*(DEL*OMEGA + ALPHA /(2*K)) NOW IN
064354,000522: # K2CNTRAL
064355,000523:
064356,000524: 21,3467 31743 DOSHIFT CA ININDEX
064357,000525: 21,3470 00006 EXTEND # MULTIPLY IN THE FACTOR 2(-S), RETURNED
064358,000526: 21,3471 74727 MP BIT14 # BY THE GTSQRT SUBROUTINE
064359,000527: 21,3472 27740 ADS SHFTFLAG
064360,000528: 21,3473 00006 EXTEND
064361,000529: 21,3474 13513 BZF ADDITIN
064362,000530: 21,3475 51740 INDEX SHFTFLAG
064363,000531: 21,3476 34726 CA BIT15
064364,000532:
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Page 1481 |
064366,000534: 21,3477 57741 XCH K2CNTRAL
064367,000535: 21,3500 00006 EXTEND
064368,000536: 21,3501 71741 MP K2CNTRAL
064369,000537: 21,3502 21737 DAS K2THETA
064370,000538: 21,3503 57741 XCH K2CNTRAL
064371,000539: 21,3504 00006 EXTEND
064372,000540: 21,3505 71742 MP K2CNTRAL +1
064373,000541: 21,3506 27737 ADS K2THETA +1
064374,000542: 21,3507 54001 TS L
064375,000543: 21,3510 13512 TCF +2
064376,000544: 21,3511 27736 ADS K2THETA
064377,000545:
064378,000546: 21,3512 13516 TCF NEGUSUM
064379,000547:
064380,000548: 21,3513 00006 ADDITIN EXTEND
064381,000549: 21,3514 31742 DCA K2CNTRAL
064382,000550: 21,3515 21737 DAS K2THETA # NOW ADD IN THE K2THETA TERM.
064383,000551: 21,3516 11736 NEGUSUM CCS K2THETA # TEST SIGN OF HIGH ORDER PART.
064384,000552: 21,3517 13523 TCF NEGDRIVE
064385,000553: 21,3520 13522 TCF +2
064386,000554: 21,3521 13525 TCF POSDRIVE
064387,000555:
064388,000556: 21,3522 11737 CCS K2THETA +1 # SIGN TEST FOR LOW ORDER PART.
064389,000557: 21,3523 34744 NEGDRIVE CA BIT1
064390,000558: 21,3524 13526 TCF +2 # STOP GIMBAL DRIVE FOR A ZERO NEGUSUM.
064391,000559: 21,3525 44744 POSDRIVE CS BIT1
064392,000560: 21,3526 54001 TS L # SAVE FOR DRIVE REVERSAL TEST.
064393,000561: 21,3527 51747 INDEX QRCNTR
064394,000562: 21,3530 57501 XCH NEGUQ
064395,000563:
064396,000564: 21,3531 00006 EXTEND
064397,000565: 21,3532 70001 MP L # MULTIPLY OLD NEGU AND NEW NEGU.
064398,000566: 21,3533 10001 CCS L
064399,000567: 21,3534 13551 TCF LOUPE # NON-ZERO GIMBAL DRIVE BEING CONTINUED.
064400,000568:
064401,000569: 21,3535 13546 TCF ZEROLOUP # NO REVERSAL PROBLEM HERE.
064402,000570:
064403,000571: 21,3536 13540 TCF REVERSAL # NON-ZERO GIMBAL DRIVE BEING REVERSED.
064404,000572: 21,3537 13546 TCF ZEROLOUP # NO REVERSAL PROBLEM HERE.
064405,000573:
064406,000574: 21,3540 51747 REVERSAL INDEX QRCNTR # A ZERO-DRIVE PAUSE IS NEEDED HERE. ZERO
064407,000575: 21,3541 55510 TS QACCDOT # IS IN A REGISTER FROM CCS ON (-1).
064408,000576: 21,3542 51747 INDEX QRCNTR
064409,000577: 21,3543 43563 CS GMBLBITA
064410,000578: 21,3544 00006 EXTEND
064411,000579: 21,3545 03012 WAND CHAN12
064412,000580:
064413,000581: 21,3546 41774 ZEROLOUP CS RCSFLAGS # SET UP REQUEST FOR ACDT+C12 CALL.
064414,000582: 21,3547 74740 MASK CALLGMBL
064415,000583: 21,3550 27774 ADS RCSFLAGS
064416,000584:
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Page 1482 |
064418,000586: 21,3551 11747 LOUPE CCS QRCNTR # HAVE BOTH AXES BEEN PROCESSED?
064419,000587: 21,3552 13045 TCF GOQTRIMG # NO. DO Q AXIS NEXT.
064420,000588:
064421,000589: 21,3553 31505 CA SAVESR # RESTORE THE SR
064422,000590: 21,3554 54021 TS SR
064423,000591:
064424,000592: 21,3555 00006 GOCLOSE EXTEND # TERMINATE THE JASK.
064425,000593: 21,3556 33561 DCA CLOSEADR
064426,000594: 21,3557 52006 DTCB
064427,000595:
064428,000596: 21,3560 E6,1536 EBANK= AOSQ
064429,000597: 21,3560 03270 36106 CLOSEADR 2CADR CLOSEOUT # TERMINATE THE JASK.
064430,000598:
064431,000599: 21,3562 5745 TWELVE EQUALS OCT14
064432,000600: 21,3562 26501 ROOTHALF OCTAL 26501 # SQUARE ROOT OF 1/2
064433,000601: 21,3563 01400 GMBLBITA OCTAL 01400 # INDEXED WRT GMBLBITB DO NOT MOVE******
064434,000602: 21,3564 11276 OCT11276 OCTAL 11276 # POSMAX - ROOTHALF
064435,000603: 21,3565 06000 GMBLBITB OCTAL 06000 # INDEXED WRT GMBLBITA DO NOT MOVE******
064436,000604:
064437,000605: # SUBROUTINE ROOTCYCL: BY CRAIG WORK,3 APRIL 68
064438,000606: # ROOTCYCL IS A SUBROUTINE WHICH EXECUTES ONE NEWTON SQUARE ROOT ALGORITHM ITERATION. THE INITIAL GUESS AT THE
064439,000607: # SQUARE ROOT IS PRESUMED TO BE IN THE A REGISTER AND ONE-HALF THE SQUARE IS TAKEN FROM HALFARG. THE NEW APPROXI-
064440,000608: # MATION TO THE SQUARE ROOT IS RETURNED IN THE A REGISTER. DEBRIS: A,L,SR,SCRATCH. ROOTCYCL IS CALLED FROM
064441,000609: # LOCATION (LOC) BY A TC ROOTCYCL, AND RETURNS (TC Q) TO LOC +1.
064442,000610:
064443,000611: # WARNING: IF THE INITIAL GUESS IS NOT GREATER THAN THE SQUARE, DIVIDE OR ADD OVERFLOW IS A REAL POSSIBILITY.
064444,000612:
064445,000613: 21,3566 55745 ROOTCYCL TS SCRATCH # STORE X
064446,000614: 21,3567 54021 TS SR # X/2 NOW IN SR
064447,000615: 21,3570 31746 CA HALFARG # ARG/2 IN THE A REG
064448,000616: 21,3571 22007 ZL # PREPARE FOR DIVISION
064449,000617: 21,3572 00006 EXTEND
064450,000618: 21,3573 11745 DV SCRATCH # (ARG/X)/2
064451,000619: 21,3574 60021 AD SR # (X + ARG/X)/2 IN THE A REG
064452,000620: 21,3575 00002 TC Q
End of include-file TRIM_GIMBAL_CONTROL_SYSTEM.agc. Parent file is MAIN.agc