Source Code
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These source-code files were from the printout at the MIT Museum, with many thanks
to Deborah Douglas, the Museum's Curator of Science and Technology, for releasing
it to us. The printout was digitally photographed by Paul Fjeld. A team of
volunteers transcribed the source code manually from these images or, where
appropriate, modified already-transcribed but similar source Luminary 131 (Apollo 13)
source code to agree with the images from the printout. Note that the page images
presented online are of reduced quality, and that higher-quality images
are available. Report any conversion errors or legibility
problems in page images to info@sandroid.org.
Notations on the program listing read, in part:GAP: ASSEMBLE REVISION 001 OF AGC PROGRAM LMY99 BY NASA 2021112-061 20'35 OCT. 28,1968Note that the date is the date of the printout, not the date of the program revision. |
063617,000002: ## Copyright: Public domain.
063618,000003: ## Filename: TRIM_GIMBAL_CNTROL_SYSTEM.agc
063619,000004: ## Purpose: Part of the source code for Luminary 1A build 099.
063620,000005: ## It is part of the source code for the Lunar Module's (LM)
063621,000006: ## Apollo Guidance Computer (AGC), for Apollo 11.
063622,000007: ## Assembler: yaYUL
063623,000008: ## Contact: Ron Burkey <info@sandroid.org>.
063624,000009: ## Website: www.ibiblio.org/apollo.
063625,000010: ## Pages: 1472-1485
063626,000011: ## Mod history: 2009-05-27 RSB Adapted from the corresponding
063627,000012: ## Luminary131 file, using page
063628,000013: ## images from Luminary 1A.
063629,000014: ## 2011-01-06 JL Fixed pseudo-label indentation.
063630,000015: ## 2016-12-18 RSB Proofed text comments with octopus/ProoferComments
063631,000016: ## and corrected the errors found.
063632,000017: ## 2017-03-14 RSB Comment-text fixes noted in proofing Luminary 116.
063633,000018:
063634,000019: ## This source code has been transcribed or otherwise adapted from
063635,000020: ## digitized images of a hardcopy from the MIT Museum. The digitization
063636,000021: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
063637,000022: ## the Museum. Many thanks to both. The images (with suitable reduction
063638,000023: ## in storage size and consequent reduction in image quality as well) are
063639,000024: ## available online at www.ibiblio.org/apollo. If for some reason you
063640,000025: ## find that the images are illegible, contact me at info@sandroid.org
063641,000026: ## about getting access to the (much) higher-quality images which Paul
063642,000027: ## actually created.
063643,000028: ##
063644,000029: ## Notations on the hardcopy document read, in part:
063645,000030: ##
063646,000031: ## Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
063647,000032: ## 16:27 JULY 14, 1969
063648,000033:
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Page 1472 |
063650,000035: 21,3077 BANK 21
063651,000036: 21,3077 E6,1450 EBANK= QDIFF
063652,000037: 21,2000 SETLOC DAPS4
063653,000038: 21,2000 BANK
063654,000039:
063655,000040: 21,3077 COUNT* $$/DAPGT
063656,000041:
063657,000042: # CONTROL REACHES THIS POINT UNDER EITHER OF THE FOLLOWING TWO CONDITIONS ONCE THE DESCENT ENGINE AND THE DIGITAL
063658,000043: # AUTOPILOT ARE BOTH ON:
063659,000044: # A) THE TRIM GIMBAL CONTROL LAW WAS ON DURING THE PREVIOUS Q,R-AXIS TIME5 INTERRUPT (OR THE DAPIDLER
063660,000045: # INITIALIZATION WAS SET FOR TRIM GIMBAL CONTROL AND THIS IS THE FIRST PASS), OR
063661,000046: # B) THE Q,R-AXES RCS AUTOPILOT DETERMINED THAT THE VEHICLE WAS ENTERING (OR HAD JUST ENTERED) A COAST
063662,000047: # ZONE WITH A SMALL OFFSET ANGULAR ACCELERATION.
063663,000048: # GTS IS THE ENTRY TO THE GIMBAL TRIM SYSTEM FOR CONTROLLING ATTITUDE ERRORS AND RATES AS WELL AS ACCELERATIONS.
063664,000049:
063665,000050: 21,3077 37747 GTS CAF NEGONE # MAKE THE NEXT PASS THROUGH THE DAP BE
063666,000051: 21,3100 55631 TS COTROLER # THROUGH RCS CONTROL,
063667,000052: 21,3101 34751 CAF FOUR # AND ENSURE THAT IT IS NOT A SKIP.
063668,000053: 21,3102 55535 TS SKIPU
063669,000054: 21,3103 55536 TS SKIPV
063670,000055:
063671,000056: 21,3104 34752 CAF TWO
063672,000057: 21,3105 55633 TS INGTS # SET INDICATOR OF GTS CONTROL POSITIVE.
063673,000058: 21,3106 55632 TS QGIMTIMR # SET TIMERS TO 200 MSEC TO AVOID BOTH
063674,000059: 21,3107 55634 TS RGIMTIMR # RUNAWAY AND INTERFERENCE BY NULLING.
063675,000060:
063676,000061: # THE DRIVE SETTING ALGORITHM
063677,000062:
063678,000063: # DEL = SGN(OMEGA + ALPHA*ABS(ALPHA)/(2*K))
063679,000064: # 2 1/2 2 3/2
063680,000065: # NEGUSUM = ERROR*K + ALPHA*(DEL*OMEGA + ALPHA /(3*K)) + DEL*K (DEL*OMEGA + ALPHA /(2*K))
063681,000066:
063682,000067: # DRIVE = -SGN(NEGUSUM)
063683,000068:
063684,000069: 21,3110 30021 CA SR # SAVE THE SR. SHIFT IT LEFT TO CORRECT
063685,000070: 21,3111 60000 AD A # FOR THE RIGHT SHIFT DUE TO EDITING.
063686,000071: 21,3112 55505 TS SAVESR
063687,000072:
063688,000073: 21,3113 34752 GTSGO+DN CAF TWO # SET INDEXER FOR R-AXIS CALCULATIONS.
063689,000074: 21,3114 13116 TCF GOQTRIMG +1
063690,000075:
063691,000076: 21,3115 34755 GOQTRIMG CAF ZERO # SET INDEXER FOR Q-AXIS CALCULATIONS
063692,000077: 21,3116 55750 TS QRCNTR
063693,000078:
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RSB 2016 — Everything between this line and the corresponding line below was missing in the Luminary 099 print-out from the MIT Museum (from which the remainder of the source-code was transcribed), presumably due to some problem with the printer. It has been filled in from snapshots of page 1472 and 1473 of a different Luminary 99 print-out, thoughtfully made for us by Don Eyles. |
063700,000085: 21,3117 51750 INDEX QRCNTR # AOS SCALED AT PI/2
063701,000086: 21,3120 31537 CA AOSQ
063702,000087: 21,3121 00006 EXTEND
063703,000088: 21,3122 74752 MP BIT2 # RESCALE AOS TO PI/4
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Page 1473 |
063705,000090: 21,3123 00006 EXTEND
063706,000091: 21,3124 13130 BZF GTSQAXIS -3 # USE FULL SCALE FOR LARGER AOS ESTIMATES.
063707,000092:
063708,000093: 21,3125 50000 INDEX A
063709,000094: 21,3126 44734 CS LIMITS # LIMITS +1 CONTAINS NEGMAX.
063710,000095: 21,3127 56001 XCH L # LIMITS -1 CONTAINS POSMAX.
063711,000096:
063712,000097: 21,3130 11750 CCS QRCNTR # PICK UP RATE FOR THIS AXIS. RATE CELLS
063713,000098: 21,3131 50000 INDEX A # ARE ADJACENT, NOT SEPARATED. AT PI/4
063714,000099: 21,3132 31436 CA EDOTQ
063715,000100: 21,3133 53744 GTSQAXIS DXCH WCENTRAL
063716,000101:
063717,000102: 21,3134 51750 INDEX QRCNTR # COLLECT K FOR THIS AXIS
063718,000103: 21,3135 31504 CA KQ
063719,000104: 21,3136 55741 TS KCENTRAL
063720,000105:
063721,000106: 21,3137 00006 EXTEND # CONTROL AUTHORITY ZERO. AVOID DRIVING
063722,000107: 21,3140 13576 BZF POSDRIVE +1 # ENGINE BELL TO THE STOPS.
063723,000108:
063724,000109: 21,3141 51750 INDEX QRCNTR # QDIFF, RDIFF ARE STORED IN D.P.
063725,000110: 21,3142 31450 CAE QDIFF
063726,000111:
063727,000112: 21,3143 00006 ALGORTHM EXTEND # Q(R)DIFF IS THETA (ERROR) SCALED AT PI.
063728,000113: 21,3144 71741 MP KCENTRAL # FORM K*ERROR AT PI(2)/2(8), IN D.P.
063729,000114: 21,3145 23737 LXCH K2THETA
063730,000115: 21,3146 00006 EXTEND
063731,000116: 21,3147 74747 MP BIT5 # RESCALE TO 4*PI(2)
063732,000117: 21,3150 53740 DXCH K2THETA
063733,000118: 21,3151 00006 EXTEND
063734,000119: 21,3152 74747 MP BIT5 # FIRST TERM OF NEGUSUM IN K2THETA.
063735,000120: 21,3153 27740 ADS K2THETA +1 # NO CARRY NEEDED D.P. AT 4*PI(2)
063736,000121:
063737,000122: 21,3154 41744 CS ACENTRAL # FORM ALPHA(2)/(2*K) AT 16*PI, IN D.P.,
063738,000123: 21,3155 00006 EXTEND # LIMITING QUOTIENT TO AVOID OVERFLOW.
063739,000124: 21,3156 74736 MP BIT14 # -ALPHA/2 IN A, SCALED AT PI/4
063740,000125: 21,3157 00006 EXTEND
063741,000126: 21,3160 71744 MP ACENTRAL # -ALPHA(2)/2 IN A,L, SCALED AT PI(2)/16
063742,000127: 21,3161 61741 AD KCENTRAL
063743,000128: 21,3162 00006 EXTEND
063744,000129: 21,3163 63200 BZMF HUGEQUOT # K-ALPHA(2)/2 SHOULD BE PNZ FO DIVISION
063745,000130:
063746,000131: 21,3164 00006 EXTEND
063747,000132: 21,3165 40001 DCS A # ALPHA(2)/2 - K
063748,000133: 21,3166 61741 AD KCENTRAL
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RSB 2016 — End of material from Don Eyles's printout. The non-blank portion of page 1473 continues below: |
063751,000136: 21,3167 00006 EXTEND
063752,000137: 21,3170 11741 DV KCENTRAL # HIGH ORDER OF QUOTIENT.
063753,000138: 21,3171 57746 XCH A2CNTRAL
063754,000139: 21,3172 30001 CA L # SHIFT UP THE REMAINDER.
063755,000140: 21,3173 22007 LXCH 7 # ZERO LOW-ORDER DIVIDEND.
063756,000141: 21,3174 00006 EXTEND
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Page 1474 |
063758,000143: 21,3175 11741 DV KCENTRAL
063759,000144: 21,3176 57747 XCH A2CNTRAL +1 # QUOTIENT STORED AT 16*PI, D.P.
063760,000145: 21,3177 13203 TCF HAVEQUOT
063761,000146:
063762,000147: 21,3200 34733 HUGEQUOT CA POSMAX
063763,000148: 21,3201 54001 TS L
063764,000149: 21,3202 53747 DXCH A2CNTRAL # LIMITED QUOTIENT STORED AT 16*PI, D.P.
063765,000150:
063766,000151: 21,3203 31743 HAVEQUOT CA WCENTRAL
063767,000152: 21,3204 00006 EXTEND
063768,000153: 21,3205 74743 MP BIT9 # RESCALE OMEGA AT 16*PI IN D.P.
063769,000154: 21,3206 53743 DXCH K2CNTRAL # LOWER WORD OVERLAYS OMEGA IN WCENTRAL
063770,000155:
063771,000156: 21,3207 00006 EXTEND
063772,000157: 21,3210 31743 DCA K2CNTRAL
063773,000158: 21,3211 53752 DXCH FUNCTION
063774,000159:
063775,000160: 21,3212 31744 CA ACENTRAL # GET ALPHA*ABS(ALPHA)/(2*K)
063776,000161: 21,3213 00006 EXTEND
063777,000162: 21,3214 63220 BZMF +4
063778,000163:
063779,000164: 21,3215 00006 EXTEND
063780,000165: 21,3216 31747 DCA A2CNTRAL
063781,000166: 21,3217 13222 TCF +3
063782,000167:
063783,000168: 21,3220 00006 EXTEND
063784,000169: 21,3221 41747 DCS A2CNTRAL
063785,000170:
063786,000171: 21,3222 21752 DAS FUNCTION # OMEGA + ALPHA*ABS(ALPHA)/2*K) AT 16*PI
063787,000172:
063788,000173: 21,3223 11751 CCS FUNCTION # DEL = +1 FOR FUNCT1 GREATER THAN ZERO.
063789,000174: 21,3224 13230 TCF POSFNCT1 # OTHERWISE DEL = -1
063790,000175: 21,3225 13227 TCF +2
063791,000176: 21,3226 13232 TCF NEGFNCT1
063792,000177:
063793,000178: 21,3227 11752 CCS FUNCTION +1 # USE LOW ORDER WORD SINCE HIGH IS ZERO
063794,000179: 21,3230 34753 POSFNCT1 CAF BIT1
063795,000180: 21,3231 13233 TCF +2
063796,000181: 21,3232 44753 NEGFNCT1 CS BIT1
063797,000182: 21,3233 55745 TS DEL
063798,000183:
063799,000184: 21,3234 11745 CCS DEL # REPLACE OMEGA BY DEL*OMEGA
063800,000185: 21,3235 13247 TCF FUNCT2 # POSITIVE DEL VALUE. PROCEED.
063801,000186: 21,3236 13240 TCF DEFUNCT
063802,000187: 21,3237 13244 TCF NEGFNCT2
063803,000188:
063804,000189: 21,3240 55742 DEFUNCT TS K2CNTRAL
063805,000190: 21,3241 55743 TS K2CNTRAL +1
063806,000191: 21,3242 13247 TCF FUNCT2
063807,000192:
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Page 1475 |
063809,000194: 21,3243 65252 NEG1/3 DEC -.33333
063810,000195:
063811,000196: 21,3244 00006 NEGFNCT2 EXTEND
063812,000197: 21,3245 41743 DCS K2CNTRAL
063813,000198: 21,3246 53743 DXCH K2CNTRAL
063814,000199:
063815,000200: 21,3247 00006 FUNCT2 EXTEND
063816,000201: 21,3250 31747 DCA A2CNTRAL
063817,000202: 21,3251 21743 DAS K2CNTRAL # DEL*OMEGA + ALPHA(2)/(2*K) AT 16*PI, D.P.
063818,000203:
063819,000204: 21,3252 31746 FUNCT3 CA A2CNTRAL
063820,000205: 21,3253 00006 EXTEND
063821,000206: 21,3254 73243 MP NEG1/3
063822,000207: 21,3255 53747 DXCH A2CNTRAL
063823,000208: 21,3256 30001 CA L
063824,000209: 21,3257 00006 EXTEND
063825,000210: 21,3260 73243 MP NEG1/3
063826,000211: 21,3261 27747 ADS A2CNTRAL +1
063827,000212: 21,3262 54001 TS L
063828,000213: 21,3263 13265 TCF +2 # A2CNTRAL NOW CONTAINS -ALPHA(2)/(6*K),
063829,000214: 21,3264 27746 ADS A2CNTRAL # SCALED AT 16*PI, IN D.P.
063830,000215:
063831,000216: 21,3265 00006 EXTEND
063832,000217: 21,3266 31743 DCA K2CNTRAL # DEL*OMEGA + ALPHA(2)/(3*K) IN A2CNTRAL,
063833,000218: 21,3267 21747 DAS A2CNTRAL # SCALED AT 16*PI, D.P.
063834,000219:
063835,000220: 21,3270 31746 CA A2CNTRAL
063836,000221: 21,3271 00006 EXTEND
063837,000222: 21,3272 71744 MP ACENTRAL
063838,000223: 21,3273 21740 DAS K2THETA
063839,000224: 21,3274 31747 CA A2CNTRAL +1
063840,000225: 21,3275 00006 EXTEND
063841,000226: 21,3276 71744 MP ACENTRAL # ACENTRAL MAY NOW BE OVERLAID.
063842,000227: 21,3277 27740 ADS K2THETA +1
063843,000228: 21,3300 54001 TS L
063844,000229: 21,3301 13303 TCF +2 # TWO TERMS OF NEGUSUM ACCUMULATED, SO FAR
063845,000230: 21,3302 27737 ADS K2THETA # SCALED AT 4*PI(2), IN D.P.
063846,000231:
063847,000232: 21,3303 31742 GETROOT CA K2CNTRAL # K*(DEL*OMEGA + ALPHA(2)/(2*K)) IS THE
063848,000233: 21,3304 00006 EXTEND # TERM FOR WHICH A SQUARE ROOT IS NEEDED.
063849,000234: 21,3305 71741 MP KCENTRAL # K AT PI/2(8)
063850,000235: 21,3306 53752 DXCH FUNCTION
063851,000236: 21,3307 31743 CA K2CNTRAL +1
063852,000237: 21,3310 00006 EXTEND
063853,000238: 21,3311 71741 MP KCENTRAL
063854,000239: 21,3312 27752 ADS FUNCTION +1
063855,000240: 21,3313 54001 TS L
063856,000241: 21,3314 13316 TCF +2
063857,000242: 21,3315 27751 ADS FUNCTION # DESIRED TERM IN FUNCTION, AT PI(2)/16
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Page 1476 |
063859,000244: 21,3316 11745 CCS DEL
063860,000245: 21,3317 13524 TCF RSTOFGTS
063861,000246: 21,3320 13566 TCF NEGUSUM
063862,000247: 21,3321 13323 TCF NEGATE
063863,000248: 21,3322 13566 TCF NEGUSUM
063864,000249:
063865,000250: 21,3323 00006 NEGATE EXTEND
063866,000251: 21,3324 41743 DCS K2CNTRAL
063867,000252: 21,3325 53743 DXCH K2CNTRAL
063868,000253: 21,3326 13524 TCF RSTOFGTS
063869,000254:
063870,000255: 16,3735 BANK 16
063871,000256: 16,3735 E6,1501 EBANK= NEGUQ
063872,000257: 16,2000 SETLOC DAPS1
063873,000258: 16,2000 BANK
063874,000259:
063875,000260: # THE WRCHN12 SUBROUTINE SETS BITS 9,10,11,12 OF CHANNEL 12 ON THE BASIS OF THE CONTENTS OF NEGUQ,NEGUR WHICH ARE
063876,000261: # THE NEGATIVES OF THE DESIRED ACCELERATION CHANGES. ACDT+C12 SETS Q(R)ACCDOT TO REFLECT THE NEW DRIVES.
063877,000262:
063878,000263: # WARNING: ACDT+C12 AND WRCHN12 MUST BE CALLED WITH INTERRUPT INHIBITED.
063879,000264:
063880,000265: 16,3735 07400 BGIM OCTAL 07400
063881,000266: 16,3736 0066 CHNL12 EQUALS ITEMP6
063882,000267: 16,3736 41501 ACDT+C12 CS NEGUQ
063883,000268: 16,3737 00006 EXTEND # GIMBAL DRIVE REQUESTS.
063884,000269: 16,3740 71507 MP ACCDOTQ
063885,000270: 16,3741 23510 LXCH QACCDOT
063886,000271: 16,3742 41503 CS NEGUR
063887,000272: 16,3743 00006 EXTEND
063888,000273: 16,3744 71511 MP ACCDOTR
063889,000274: 16,3745 23512 LXCH RACCDOT
063890,000275:
063891,000276: 16,3746 11501 CCS NEGUQ
063892,000277: 16,3747 34742 CAF BIT10
063893,000278: 16,3750 13752 TCF +2
063894,000279: 16,3751 34743 CAF BIT9
063895,000280: 16,3752 54066 TS CHNL12
063896,000281:
063897,000282: 16,3753 11503 CCS NEGUR
063898,000283: 16,3754 34740 CAF BIT12
063899,000284: 16,3755 13757 TCF +2
063900,000285: 16,3756 34741 CAF BIT11
063901,000286: 16,3757 26066 ADS CHNL12 # (STORED RESULT NOT USED AT PRESENT)
063902,000287:
063903,000288: 16,3760 43735 CS BGIM
063904,000289: 16,3761 00006 EXTEND
063905,000290: 16,3762 02012 RAND CHAN12
063906,000291: 16,3763 60066 AD CHNL12
063907,000292: 16,3764 00006 EXTEND
063908,000293: 16,3765 01012 WRITE CHAN12
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Page 1477 |
063910,000295: 16,3766 44747 CS CALLGMBL # TURN OFF REQUEST FOR ACDT+C12 EXECUTION.
063911,000296: 16,3767 71273 MASK RCSFLAGS
063912,000297: 16,3770 55273 TS RCSFLAGS
063913,000298:
063914,000299: 16,3771 00002 TC Q # RETURN TO CALLER.
063915,000300:
063916,000301: 21,3327 BANK 21
063917,000302: 21,3327 E6,1450 EBANK= QDIFF
063918,000303: 21,2000 SETLOC DAPS4
063919,000304: 21,2000 BANK
063920,000305:
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Page 1478 |
063922,000307: # SUBROUTINE TIMEGMBL: MOD 0, OCTOBER 1967, CRAIG WORK
063923,000308:
063924,000309: # TIMEGMBL COMPUTES THE DRIVE TIME NEEDED FOR THE TRIM GIMBAL TO POSITION THE DESCENT ENGINE NOZZLE SO AS TO NULL
063925,000310: # THE OFFSET ANGULAR ACCELERATION ABOUT THE Q (OR R) AXIS. INSTEAD OF USING AOSQ(R), TIMEGMBL USES .4*AOSQ(R),
063926,000311: # SCALED AT PI/8. FOR EACH AXIS, THE DRIVE TIME IS COMPUTED AS ABS(ALPHA/ACCDOT). A ZERO
063927,000312: # ALPHA OR ACCDOT OR A ZERO QUOTIENT TURNS OFF THE GIMBAL DRIVE IMMEDIATELY. OTHERWISE, THE GIMBAL IS TURNED ON
063928,000313: # DRIVING IN THE CORRECT DIRECTION. THE Q(R)GIMTIMR IS SET TO TERMINATE THE DRIVE AND Q(R)ACCDOT
063929,000314: # IS STORED TO REFLECT THE NEW ACCELERATION DERIVATIVE. NEGUQ(R) WILL CONTAIN +1,+0,-1 FOR A Q(R)ACCDOT VALUE
063930,000315: # WHICH IS NEGATIVE, ZERO, OR POSITIVE.
063931,000316:
063932,000317: # INPUTS: AOSQ,AOSR, SCALED AT P1/2, AND ACCDOTQ, ACCDOTR AT PI/2(7). PI/2(7).
063933,000318:
063934,000319: # OUTPUTS: NEW GIMBAL DRIVE BITS IN CHANNEL 12, NEGUQ, NEGUR, QACCDOT AND RACCDOT, THE LAST SCALED AT PI/2(7).
063935,000320: # Q(R)GIMTIMR WILL BE SET TO TIME AND TERMINATE GIMBAL DRIVE(S)
063936,000321:
063937,000322: # DEBRIS: A, L, Q, ITEMPS 2, 3, 6, RUPTREG2 AND ACDT+C12 DEBRIS.
063938,000323:
063939,000324: # EXITS: VIA TC Q.
063940,000325:
063941,000326: # ALARMS, ABORTS, : NONE
063942,000327:
063943,000328: # SUBROUTINES: ACDT+C12, IBNKCALL
063944,000329:
063945,000330: # WARNING: THIS SUBROUTINE WRITES INTO CHANNEL 12 AND USES THE ITEMPS. THEREFORE IT MAY ONLY BE CALLED WITH
063946,000331: # INTERRUPT INHIBITED.
063947,000332:
063948,000333: # ERASABLE STORAGE CONFIGURATION (NEEDED BY THE INDEXING METHODS):
063949,000334: # NEGUQ ERASE +2 NEGATIVE OF Q-AXIS GIMBAL DRIVE
063950,000335: # (SPWORD) EQUALS NEGUQ +1 ANY S.P. ERASABLE NUMBER, NOW THRSTCMD
063951,000336: # NEGUR EQUALS NEGUQ +2 NEGATIVE OF R-AXIS GIMBAL DRIVE
063952,000337: # ACCDOTQ ERASE +2 Q-JERK TERM SCALED AT PI/2(7) RAD/SEC(3)
063953,000338: # (SPWORD) EQUALS ACCDOTQ +1 ANY S.P. ERASABLE NUMBER NOW QACCDOT
063954,000339: # ACCDOTR EQUALS ACCDOTQ +2 R-JERK TERM SCALED AT PI/2(7) RAD/SEC(3)
063955,000340: # ACCDOTQ, ACCDOTR ARE MAGNITUDES.
063956,000341: # AOSQ ERASE +4 Q-AXIS ACC., D.P. AT PI/2 R/SEC(2)
063957,000342: # AOSR EQUALS AOSQ +2 R-AXIS ACCELERATION SCALED AT PI/2 R/S2
063958,000343:
063959,000344: 21,3327 0066 QRNDXER EQUALS ITEMP6
063960,000345: 21,3327 23146 OCT23146 OCTAL 23146 # DECIMAL .6
063961,000346: 21,3330 0063 NZACCDOT EQUALS ITEMP3
063962,000347:
063963,000348: 21,3330 34753 TIMEGMBL CAF ONE # INITIALIZE ALLOWGTS.
063964,000349: 21,3331 55502 TS ALLOWGTS
063965,000350:
063966,000351: 21,3332 34752 CAF TWO # SET UP LOOP FOR R AXIS.
063967,000352: 21,3333 22002 LXCH Q # SAVE RETURN ADDRESS.
063968,000353: 21,3334 22071 LXCH RUPTREG2
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Page 1479 |
063970,000355: 21,3335 13337 TCF +2
063971,000356: 21,3336 34755 TIMQGMBL CAF ZERO # NOW DO THE Q-AXIS
063972,000357: 21,3337 54066 TS QRNDXER
063973,000358: 21,3340 50066 INDEX QRNDXER
063974,000359: 21,3341 31507 CA ACCDOTQ # ACCDOT IS PRESUMED TO BE AT PI/2(7).
063975,000360: 21,3342 00006 EXTEND
063976,000361: 21,3343 63413 BZMF TGOFFNOW # IS ACCDOT LESS THAN OR EQUAL TO 0?
063977,000362: 21,3344 54063 TS NZACCDOT # NO. STORE NON-ZERO, POSITIVE ACCDOT.
063978,000363:
063979,000364: 21,3345 50066 ALPHATRY INDEX QRNDXER
063980,000365: 21,3346 41537 CS AOSQ
063981,000366: 21,3347 00006 EXTEND
063982,000367: 21,3350 13413 BZF TGOFFNOW # IS ALPHA ZERO?
063983,000368:
063984,000369: 21,3351 54002 TS Q # SAVE A COPY OF -AOS.
063985,000370: 21,3352 00006 EXTEND # NO. RESCALE FOR TIMEGMBL USE.
063986,000371: 21,3353 73327 MP OCT23146 # OCTAL 23146 IS DECIMAL .6
063987,000372: 21,3354 60002 AD Q # -1.6*AOS AT PI/2 = -.4*AOS AT PI/8.
063988,000373: 21,3355 54001 TS L # WAS THERE OVERFLOW?
063989,000374: 21,3356 13363 TCF SETNEGU # NO. COMPUTE DRIVE TIME.
063990,000375:
063991,000376: 21,3357 40000 CS A # RECOVER -SGN(AOS) IN THE A REGISTER.
063992,000377: 21,3360 50066 INDEX QRNDXER # YES. START DRIVE WITHOUT WAITLIST.
063993,000378: 21,3361 57501 XCH NEGUQ
063994,000379: 21,3362 13417 TCF NOTALLOW # KNOCK DOWN THE ALLOWGTS FLAG.
063995,000380:
063996,000381: 21,3363 00006 SETNEGU EXTEND
063997,000382: 21,3364 63371 BZMF POSALPH
063998,000383:
063999,000384: 21,3365 40000 COM
064000,000385: 21,3366 54062 TS ITEMP2 # STORE -ABS(.4*AOS) SCALED AT PI/8.
064001,000386: 21,3367 44753 CS BIT1
064002,000387: 21,3370 13373 TCF POSALPH +2
064003,000388: 21,3371 54062 POSALPH TS ITEMP2 # STORE -ABS(.4*AOS) SCALED AT PI/8.
064004,000389: 21,3372 34753 CA BIT1
064005,000390: 21,3373 50066 +2 INDEX QRNDXER # SGN(AOS) INTO NEGU
064006,000391: 21,3374 55501 TS NEGUQ # STORE SGN(APLHA) AS NEGU
064007,000392:
064008,000393: 21,3375 30063 CA NZACCDOT
064009,000394: 21,3376 00006 EXTEND
064010,000395: 21,3377 74740 MP BIT12 # 2*ACCDOT, SCALED AT PI/8.
064011,000396: 21,3400 60062 AD ITEMP2 # -ABS(ALPHA) + 2*ACCDOT, AT PI/8.
064012,000397: 21,3401 00006 EXTEND
064013,000398: 21,3402 63417 BZMF NOTALLOW # IS DRIVE TIME MORE THAN TWO SECONDS?
064014,000399: 21,3403 40062 CS ITEMP2 # NO. COMPUTE DRIVE TIME.
064015,000400: 21,3404 00006 EXTEND # ABS(ALPHA) AT PI/8.
064016,000401: 21,3405 73440 MP OCT00240 # DECIMAL 10/1024
064017,000402: 21,3406 00006 EXTEND # QUOTIENT IS DRIVE TIME AT WAITLIST.
064018,000403: 21,3407 10063 DV NZACCDOT # ABS(ALPHA)/ACCDOT AT 2(14)/100
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Page 1480 |
064020,000405: 21,3410 00006 EXTEND
064021,000406: 21,3411 13413 BZF TGOFFNOW # DRIVE TIME MUST BE GREATER THAN ZERO.
064022,000407:
064023,000408: 21,3412 13425 TCF DRIVEON
064024,000409:
064025,000410: 21,3413 34755 TGOFFNOW CAF ZERO # TURN OFF GIMBAL NOW.
064026,000411: 21,3414 50066 INDEX QRNDXER
064027,000412: 21,3415 55501 TS NEGUQ
064028,000413:
064029,000414: 21,3416 13427 TCF DONEYET
064030,000415:
064031,000416: 21,3417 36010 NOTALLOW CAF OCT31
064032,000417: 21,3420 50066 INDEX QRNDXER
064033,000418: 21,3421 55632 TS QGIMTIMR
064034,000419: 21,3422 34755 CAF ZERO # DRIVE TIME IS MORE THAN 2 SECONDS, SO
064035,000420: 21,3423 55502 TS ALLOWGTS # DO NOT PERMIT FURTHER GTS ATTITUDE-RATE
064036,000421: # CONTROL UNTIL AOSTASK APPROVES.
064037,000422: 21,3424 13427 TCF DONEYET # NO WAITLIST CALL IS MADE.
064038,000423:
064039,000424: 21,3425 50066 DRIVEON INDEX QRNDXER
064040,000425: 21,3426 55632 TS QGIMTIMR # CHOOSE Q OR R AXIS.
064041,000426:
064042,000427: 21,3427 10066 DONEYET CCS QRNDXER
064043,000428: 21,3430 13336 TCF TIMQGMBL
064044,000429:
064045,000430: 21,3431 52073 DXCH RUPTREG3 # PROTECT IBNKCALL ERASABLES. ACDT+C12
064046,000431: 21,3432 52063 DXCH ITEMP2 # LEAVES ITEMPS2,3 ALONE.
064047,000432:
064048,000433: 21,3433 04674 TC IBNKCALL # TURN OF CHANNEL BITS, SET Q(R)ACCDOTS.
064049,000434: 21,3434 35736 CADR ACDT+C12
064050,000435:
064051,000436: 21,3435 52063 DXCH ITEMP2 # RESTORE ERASABLES FOR IBNKCALL.
064052,000437: 21,3436 52073 DXCH RUPTREG3
064053,000438:
064054,000439: 21,3437 00071 TC RUPTREG2 # RETURN TO CALLER.
064055,000440:
064056,000441: 21,3440 00240 OCT00240 OCTAL 00240 # DECIMAL 10/1024
064057,000442:
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Page 1481 |
064059,000444: # THE FOLLOWING SECTION IS A CONTINUATION OF THE TRIM GIMBAL CONTROL FROM THE LAST GTS ENTRY. THE QUANTITY NEGUSUM
064060,000445: # IS COMPUTED FOR EACH AXIS (Q,R), .707*DEL*FUNCTION(3/2) + K2THETA = NEGUSUM. NEW DRIVES ARE ENTERED TO CH 12.
064061,000446:
064062,000447: # THE SUBROUTINE GTSQRT ACCEPTS A DOUBLE PRECISION VALUE IN FUNCTION, FUNCTION +1 AND RETURNS A SINGLE-PRECISION
064063,000448: # SQUARE ROOT OF THE FOURTEEN MOST SIGNIFICANT BITS OF THE ARGUMENT. ALSO, THE CELL SHFTFLAG CONTAINS A BINARY
064064,000449: # EXPONENT S, SUCH THAT THE SQUARE ROOT (RETURNED IN THE A REGISTER) MUST BE SHIFTED RIGHT (MULTIPLIED BY 2 TO THE
064065,000450: # POWER (-S)) IN ORDER TO BE THE TRUE SQUARE ROOT OF THE FOURTEEN MOST SIGNIFICANT BITS OF FUNCTION, FUNCTION +1.
064066,000451: # SQUARE ROOT ERROR IS NOT MORE THAN 2 IN THE 14TH SIGNIFICANT BIT. CELLS CLOBBERED ARE A, L, SHFTFLAG, ININDEX,
064067,000452: # HALFARG, SCRATCH, SR, FUNCTION, FUNCTION +1. GTSQRT IS CALLED BY TC GTSQRT AND RETURNS VIA TC Q OR TC FUNCTION +1.
064068,000453: # ZERO OR NEGATIVE ARGUMENTS YIELD ZERO FOR SQUARE ROOTS.
064069,000454:
064070,000455: 21,3441 11751 GTSQRT CCS FUNCTION
064071,000456: 21,3442 13460 TCF GOODARG # FUNCTION IS POSITIVE. TAKE SQUARE ROOT.
064072,000457: 21,3443 13445 TCF +2 # HIGH ORDER WORD IS ZERO. TRY THE LOWER.
064073,000458: 21,3444 13451 TCF ZEROOT # NEGATIVE. USE ZERO FOR 1/2 POWER.
064074,000459:
064075,000460: 21,3445 31752 CA FUNCTION +1
064076,000461: 21,3446 00006 EXTEND
064077,000462: 21,3447 63451 BZMF ZEROOT
064078,000463:
064079,000464: 21,3450 13454 TCF ZEROHIGH # PROCEED.
064080,000465: 21,3451 34755 ZEROOT CA ZERO
064081,000466: 21,3452 55741 TS SHFTFLAG
064082,000467: 21,3453 00002 TC Q
064083,000468:
064084,000469: 21,3454 57751 ZEROHIGH XCH FUNCTION # 14 MOST SIGNIFICANT BITS ARE IN THE
064085,000470: 21,3455 57752 XCH FUNCTION +1 # LOWER WORD. EXCHANGE THEM.
064086,000471: 21,3456 34757 CA SEVEN
064087,000472: 21,3457 13461 TCF GOODARG +1
064088,000473:
064089,000474: 21,3460 34755 GOODARG CA ZERO
064090,000475: 21,3461 55741 TS SHFTFLAG
064091,000476: 21,3462 35751 CA TWELVE # INITIALIZE THE SCALING LOOP.
064092,000477: 21,3463 55744 TS ININDEX
064093,000478: 21,3464 13473 TCF SCALLOOP
064094,000479:
064095,000480: 21,3465 31751 SCALSTRT CA FUNCTION
064096,000481: 21,3466 13507 TCF SCALDONE
064097,000482:
064098,000483: 21,3467 37746 MULBUSH CA NEG2 # IF ARG IS NOT LESS THAN 1/4, INDEX IS
064099,000484: 21,3470 27744 ADS ININDEX # ZERO, INDICATING NO SHIFT NEEDED.
064100,000485: 21,3471 00006 EXTEND # BRANCH IF ARG IS NOT LESS THAN 1/4.
064101,000486: 21,3472 63465 BZMF SCALSTRT # OTHERWISE COMPARE ARG WITH A REFERENCE
064102,000487: # WHICH IS 4 TIMES LARGER THAN THE LAST.
064103,000488: 21,3473 41751 SCALLOOP CS FUNCTION
064104,000489: 21,3474 51744 INDEX ININDEX
064105,000490: 21,3475 64735 AD BIT15 # REFERENCE MAGNITUDE LESS OR EQUAL TO 1/4
064106,000491: 21,3476 00006 EXTEND
064107,000492: 21,3477 63467 BZMF MULBUSH # IF ARG IS NOT LESS THAN REFERENCE, GO
064108,000493: # AROUND THE MULBERRY BUSH ONCE MORE.
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Page 1482 |
064110,000495: 21,3500 51744 INDEX ININDEX
064111,000496: 21,3501 34735 CA BIT15 # THIS IS THE SCALE MAGNITUDE
064112,000497: 21,3502 57747 XCH HALFARG # 2**(-ININDEX) IS THE SHIFT DIVISOR.
064113,000498: 21,3503 00006 EXTEND # RESCALE ARGUMENT.
064114,000499: 21,3504 31752 DCA FUNCTION
064115,000500: 21,3505 00006 EXTEND
064116,000501: 21,3506 11747 DV HALFARG
064117,000502: # ININDEX AND SHFTFLAG PRESERVE INFO FOR
064118,000503: # RESCALING AFTER ROOT PROCESS.
064119,000504: 21,3507 00006 SCALDONE EXTEND
064120,000505: 21,3510 23752 QXCH FUNCTION +1 # SAVE Q FOR RETURN
064121,000506: 21,3511 00006 EXTEND
064122,000507: 21,3512 74736 MP BIT14
064123,000508: 21,3513 55747 TS HALFARG
064124,000509: 21,3514 74737 MASK BIT13
064125,000510: 21,3515 10000 CCS A
064126,000511: 21,3516 33634 CA OCT11276
064127,000512: 21,3517 63632 AD ROOTHALF # INITIAL GUESS IS ROOT 1/2 OR POSMAX
064128,000513: 21,3520 03636 TC ROOTCYCL
064129,000514: 21,3521 03636 TC ROOTCYCL
064130,000515: 21,3522 03636 TC ROOTCYCL
064131,000516: 21,3523 01752 TC FUNCTION +1
064132,000517:
064133,000518: # ****************************************************************************************************************
064134,000519:
064135,000520: 21,3524 03441 RSTOFGTS TC GTSQRT
064136,000521: 21,3525 57742 PRODUCT XCH K2CNTRAL
064137,000522: 21,3526 00006 EXTEND
064138,000523: 21,3527 71742 MP K2CNTRAL
064139,000524: 21,3530 53743 DXCH K2CNTRAL
064140,000525: 21,3531 00006 EXTEND # THE PRODUCT OF
064141,000526: 21,3532 70001 MP L # 1/2 2 1/2
064142,000527: 21,3533 27743 ADS K2CNTRAL +1 # K *(DEL*OMEGA + ALPHA /(2*K))
064143,000528: 21,3534 54001 TS L # AND
064144,000529: 21,3535 13537 TCF +2 # 2
064145,000530: 21,3536 27742 ADS K2CNTRAL # DEL*(DEL*OMEGA + ALPHA /(2*K)) NOW IN
064146,000531: # K2CNTRAL
064147,000532:
064148,000533: 21,3537 31744 DOSHIFT CA ININDEX
064149,000534: 21,3540 00006 EXTEND # MULTIPLY IN THE FACTOR 2(-S), RETURNED
064150,000535: 21,3541 74736 MP BIT14 # BY THE GTSQRT SUBROUTINE
064151,000536: 21,3542 27741 ADS SHFTFLAG
064152,000537: 21,3543 00006 EXTEND
064153,000538: 21,3544 13563 BZF ADDITIN
064154,000539: 21,3545 51741 INDEX SHFTFLAG
064155,000540: 21,3546 34735 CA BIT15
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Page 1483 |
064157,000542: 21,3547 57742 XCH K2CNTRAL
064158,000543: 21,3550 00006 EXTEND
064159,000544: 21,3551 71742 MP K2CNTRAL
064160,000545: 21,3552 21740 DAS K2THETA
064161,000546: 21,3553 57742 XCH K2CNTRAL
064162,000547: 21,3554 00006 EXTEND
064163,000548: 21,3555 71743 MP K2CNTRAL +1
064164,000549: 21,3556 27740 ADS K2THETA +1
064165,000550: 21,3557 54001 TS L
064166,000551: 21,3560 13562 TCF +2
064167,000552: 21,3561 27737 ADS K2THETA
064168,000553:
064169,000554: 21,3562 13566 TCF NEGUSUM
064170,000555:
064171,000556: 21,3563 00006 ADDITIN EXTEND
064172,000557: 21,3564 31743 DCA K2CNTRAL
064173,000558: 21,3565 21740 DAS K2THETA # NOW ADD IN THE K2THETA TERM.
064174,000559: 21,3566 11737 NEGUSUM CCS K2THETA # TEST SIGN OF HIGH ORDER PART.
064175,000560: 21,3567 13573 TCF NEGDRIVE
064176,000561: 21,3570 13572 TCF +2
064177,000562: 21,3571 13575 TCF POSDRIVE
064178,000563:
064179,000564: 21,3572 11740 CCS K2THETA +1 # SIGN TEST FOR LOW ORDER PART.
064180,000565: 21,3573 34753 NEGDRIVE CA BIT1
064181,000566: 21,3574 13576 TCF +2 # STOP GIMBAL DRIVE FOR A ZERO NEGUSUM.
064182,000567: 21,3575 44753 POSDRIVE CS BIT1
064183,000568: 21,3576 54001 TS L # SAVE FOR DRIVE REVERSAL TEST.
064184,000569: 21,3577 51750 INDEX QRCNTR
064185,000570: 21,3600 57501 XCH NEGUQ
064186,000571:
064187,000572: 21,3601 00006 EXTEND
064188,000573: 21,3602 70001 MP L # MULTIPLY OLD NEGU AND NEW NEGU.
064189,000574: 21,3603 10001 CCS L
064190,000575: 21,3604 13621 TCF LOUPE # NON-ZERO GIMBAL DRIVE BEING CONTINUED.
064191,000576:
064192,000577: 21,3605 13616 TCF ZEROLOUP # NO REVERSAL PROBLEM HERE.
064193,000578:
064194,000579: 21,3606 13610 TCF REVERSAL # NON-ZERO GIMBAL DRIVE BEING REVERSED.
064195,000580: 21,3607 13616 TCF ZEROLOUP # NO REVERSAL PROBLEM HERE.
064196,000581:
064197,000582: 21,3610 51750 REVERSAL INDEX QRCNTR # A ZERO-DRIVE PAUSE IS NEEDED HERE. ZERO
064198,000583: 21,3611 55510 TS QACCDOT # IS IN A REGISTER FROM CCS ON (-1).
064199,000584: 21,3612 51750 INDEX QRCNTR
064200,000585: 21,3613 43633 CS GMBLBITA
064201,000586: 21,3614 00006 EXTEND
064202,000587: 21,3615 03012 WAND CHAN12
064203,000588:
064204,000589: 21,3616 41273 ZEROLOUP CS RCSFLAGS # SET UP REQUEST FOR ACDT+C12 CALL.
064205,000590: 21,3617 74747 MASK CALLGMBL
064206,000591: 21,3620 27273 ADS RCSFLAGS
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Page 1484 |
064208,000593: 21,3621 11750 LOUPE CCS QRCNTR # HAVE BOTH AXES BEEN PROCESSED?
064209,000594: 21,3622 13115 TCF GOQTRIMG # NO. DO Q AXIS NEXT.
064210,000595:
064211,000596: 21,3623 31505 CA SAVESR # RESTORE THE SR
064212,000597: 21,3624 54021 TS SR
064213,000598:
064214,000599: 21,3625 00006 GOCLOSE EXTEND # TERMINATE THE JASK.
064215,000600: 21,3626 33631 DCA CLOSEADR
064216,000601: 21,3627 52006 DTCB
064217,000602:
064218,000603: 21,3630 E6,1537 EBANK= AOSQ
064219,000604: 21,3630 03236 36106 CLOSEADR 2CADR CLOSEOUT # TERMINATE THE JASK.
064220,000605:
064221,000606: 21,3632 5751 TWELVE EQUALS OCT14
064222,000607: 21,3632 26501 ROOTHALF OCTAL 26501 # SQUARE ROOT OF 1/2
064223,000608: 21,3633 01400 GMBLBITA OCTAL 01400 # INDEXED WRT GMBLBITB DO NOT MOVE ******
064224,000609: 21,3634 11276 OCT11276 OCTAL 11276 # POSMAX - ROOTHALF
064225,000610: 21,3635 06000 GMBLBITB OCTAL 06000 # INDEXED WRT GMBLBITA DO NOT MOVE ******
064226,000611:
064227,000612: # SUBROUTINE ROOTCYCL: BY CRAIG WORK, 3 APRIL 68
064228,000613:
064229,000614: # ROOTCYCL IS A SUBROUTINE WHICH EXECUTES ONE NEWTON SQUARE ROOT ALGORITHM ITERATION. THE INITIAL GUESS AT THE
064230,000615: # SQUARE ROOT IS PRESUMED TO BE IN THE A REGISTER AND ONE-HALF THE SQUARE IS TAKEN FROM HALFARG. THE NEW APPROXI-
064231,000616: # MATION TO THE SQUARE ROOT IS RETURNED IN THE A REGISTER. DEBRIS: A, L, SR, SCRATCH. ROOTCYCL IS CALLED FROM
064232,000617: # LOCATION (LOC) BY A TC ROOTCYCL, AND RETURNS (TC Q) TO LOC +1.
064233,000618:
064234,000619: # WARNING: IF THE INITIAL GUESS IS NOT GREATER THAN THE SQUARE, DIVIDE OR ADD OVERFLOW IS A REAL POSSIBILITY.
064235,000620:
064236,000621: 21,3636 55746 ROOTCYCL TS SCRATCH # STORE X
064237,000622: 21,3637 54021 TS SR # X/2 NOW IN SR
064238,000623: 21,3640 31747 CA HALFARG # ARG/2 IN THE A REG
064239,000624: 21,3641 22007 ZL # PREPARE FOR DIVISION
064240,000625: 21,3642 00006 EXTEND
064241,000626: 21,3643 11746 DV SCRATCH # (ARG/X)/2
064242,000627: 21,3644 60021 AD SR # (X + ARG/X)/2 IN THE A REG
064243,000628: 21,3645 00002 TC Q
064244,000629:
064245,000630:
End of include-file TRIM_GIMBAL_CONTROL_SYSTEM.agc. Parent file is MAIN.agc