Source Code
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These source-code files were derived originally from the scan from MIT's Dibner Institute's
now-discontinued website titled "History of Recent Science and Technology". It is believed
that the original listing was preserved by AGC developer Don Eyles, copied/reduced by
AGC developer Hugh Blair-Smith, passed by AGC developer James Kernan to collector David Craig,
scanned by Gary Neff, and then passed to the Dibner Institute
where unfortunately the high-quality scans were reduced in legibility as part of the
online-presentation process, and the original scans discarded.
The source code was transcribed from
those images by Ron Burkey. The images from the Dibner Institute website, and unfortunately not
the discarded original high-quality scans, though with a few high-quality replacement scans
provided directly by Gary Neff, are now available
at the Virtual AGC project website.
Report any conversion errors to info@sandroid.org.
Notations on the program listing read, in part:GAP: ASSEMBLE REVISION 131 OF AGC PROGRAM LUMINARY BY NASA 2021112-091 17:53 DEC. 19, 1969Note that the date is the date of the printout, not the date of the program revision. |
061467,000002: ## Copyright: Public domain.
061468,000003: ## Filename: TRIM_GIMBAL_CNTROL_SYSTEM.agc
061469,000004: ## Purpose: A section of Luminary 1C, revision 131.
061470,000005: ## It is part of the source code for the Lunar Module's (LM)
061471,000006: ## Apollo Guidance Computer (AGC) for Apollo 13 and Apollo 14.
061472,000007: ## This file is intended to be a faithful transcription, except
061473,000008: ## that the code format has been changed to conform to the
061474,000009: ## requirements of the yaYUL assembler rather than the
061475,000010: ## original YUL assembler.
061476,000011: ## Reference: pp. 1469-1481 of 1729.pdf.
061477,000012: ## Contact: Ron Burkey <info@sandroid.org>.
061478,000013: ## Website: www.ibiblio.org/apollo/index.html
061479,000014: ## Mod history: 06/08/03 RSB. Began transcribing.
061480,000015: ## 05/14/05 RSB Corrected website reference above.
061481,000016: ## 2010-10-25 JL Indentation fixes.
061482,000017:
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Page 1469 |
061484,000019: 21,3076 BANK 21
061485,000020: 21,3076 E6,1450 EBANK= QDIFF
061486,000021: 21,2000 SETLOC DAPS4
061487,000022: 21,2000 BANK
061488,000023:
061489,000024: 21,3076 COUNT* $$/DAPGT
061490,000025:
061491,000026: # CONTROL REACHES THIS POINT UNDER EITHER OF THE FOLLOWING TWO CONDITIONS ONCE THE DESCENT ENGINE AND THE DIGITAL
061492,000027: # AUTOPILOT ARE BOTH ON:
061493,000028: # A) THE TRIM GIMBAL CONTROL LAW WAS ON DURING THE PREVIOUS Q,R-AXIS TIME5 INTERRUP1 (OR THE DAPIDLER
061494,000029: # INITIALIZATION WAS SET FOR TRIM GIMBAL CONTROL AND THIS IS THE FIRST PASS), OR
061495,000030: # B) THE Q,R-AXES RCS AUTOPILOT DETERMINED THAT THE VEHICLE WAS ENTERING (OR HAD JUST ENTERED) A COAST
061496,000031: # ZONE WITH A SMALL OFFSET ANGULAR ACCELERATION.
061497,000032: # GTS IS THE ENTRY TO THE GIMBAL TRIM SYSTEM FOR CONTROLLING ATTITUDE ERRORS AND RATES AS WELL AS ACCELERATIONS.
061498,000033:
061499,000034: 21,3076 37752 GTS CAF NEGONE # MAKE THE NEXT PASS THROUGH THE DAP BE
061500,000035: 21,3077 55630 TS COTROLER # THROUGH RCS CONTROL,
061501,000036: 21,3100 34751 CAF FOUR # AND ENSURE THAT IT IS NOT A SKIP.
061502,000037: 21,3101 55534 TS SKIPU
061503,000038: 21,3102 55535 TS SKIPV
061504,000039:
061505,000040: 21,3103 34752 CAF TWO
061506,000041: 21,3104 55632 TS INGTS # SET INDICATOR OF GTS CONTROL POSITIVE.
061507,000042: 21,3105 55631 TS QGIMTIMR # SET TIMERS TO 200 MSEC TO AVOID BOTH
061508,000043: 21,3106 55633 TS RGIMTIMR # RUNAWAY AND INTERFERENCE BY NULLING.
061509,000044:
061510,000045: # THE DRIVE SETTING ALGORITHM
061511,000046: # DEL = SGN(OMEGA + ALPHA*ABS(ALPHA)/(2*K)) 2 1/2 2 3/2
061512,000047: # NEGUSUM = ERROR*K + ALPHA*(DEL*OMETA + ALPHA /(3*K)) + DEL*K (DEL*OMEGA + ALPHA /(2*K))
061513,000048: # DRIVE = -SGN(NEGUSUM)
061514,000049:
061515,000050: 21,3107 30021 CA SR # SAVE THE SR. SHIFT IT LEFT TO CORRECT
061516,000051: 21,3110 60000 AD A # FOR THE RIGHT SHIFT DUE TO EDITING.
061517,000052: 21,3111 55505 TS SAVESR
061518,000053:
061519,000054: 21,3112 34752 GTSGO+DN CAF TWO # SET INDEXER FOR R-AXIS CALCULATIONS.
061520,000055: 21,3113 13115 TCF GOQTRIMG +1
061521,000056:
061522,000057: 21,3114 34755 GOQTRIMG CAF ZERO # SET INDEXER FOR Q-AXIS CALCULATIONS
061523,000058: 21,3115 55747 TS QRCNTR
061524,000059:
061525,000060: 21,3116 51747 INDEX QRCNTR # AOS SCALED AT PI/2
061526,000061: 21,3117 31536 CA AOSQ
061527,000062: 21,3120 00006 EXTEND
061528,000063: 21,3121 74752 MP BIT2 # RESCALE AOS TO PI/4
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Page 1470 |
061530,000065: 21,3122 00006 EXTEND
061531,000066: 21,3123 13127 BZF GTSQAXIS -3 # USE FULL SCALE FOR LARGER AOS ESTIMATES.
061532,000067:
061533,000068: 21,3124 50000 INDEX A
061534,000069: 21,3125 44734 CS LIMITS # LIMITS +1 CONTAINS NEGMAX.
061535,000070: 21,3126 56001 XCH L # LIMITS -1 CONTAINS POSMAX.
061536,000071:
061537,000072: 21,3127 11747 CCS QRCNTR # PICK UP RATE FOR THIS AXIS. RATE CELLS
061538,000073: 21,3130 50000 INDEX A # USE ADJACENT, NOT SEPARATED. AT PI/4
061539,000074: 21,3131 31436 CA EDOTQ
061540,000075: 21,3132 53743 GTSQAXIS DXCH WCENTRAL
061541,000076:
061542,000077: 21,3133 51747 INDEX QRCNTR # COLLECT K FOR THIS AXIS
061543,000078: 21,3134 31504 CA KQ
061544,000079: 21,3135 55740 TS KCENTRAL
061545,000080:
061546,000081: 21,3136 00006 EXTEND # CONTROL AUTHORITY ZERO. AVOID DRIVING
061547,000082: 21,3137 13575 BZF POSDRIVE +1 # ENGINE BELL TO THE STOPS.
061548,000083:
061549,000084: 21,3140 51747 INDEX QRCNTR # QDIFF, RDIFF ARE STORED IN D.P.
061550,000085: 21,3141 31450 CAE QDIFF
061551,000086:
061552,000087: 21,3142 00006 ALGORTHM EXTEND # Q(R)DIFF IS THETA (ERROR) SCALED AT PI.
061553,000088: 21,3143 71740 MP KCENTRAL # FORM K*ERROR AT PI(2)/2(8), IN D.P.
061554,000089: 21,3144 23736 LXCH K2THETA
061555,000090: 21,3145 00006 EXTEND
061556,000091: 21,3146 74747 MP BIT5 # RESCALE TO 4*PI(2)
061557,000092: 21,3147 53737 DXCH K2THETA
061558,000093: 21,3150 00006 EXTEND
061559,000094: 21,3151 74747 MP BIT5 # FIRST TERM OF NEGUSUM IN K2THETA.
061560,000095: 21,3152 27737 ADS K2THETA +1 # NO CARRY NEEDED D.P. AT 4*PI(2)
061561,000096:
061562,000097: 21,3153 41743 CS ACENTRAL # FORM ALPHA(2)/(2*K) AT 16*PI, IN D.P.,
061563,000098: 21,3154 00006 EXTEND # LIMITING QUOTIENT TO AVOID OVERFLOW.
061564,000099: 21,3155 74736 MP BIT14 # -ALPHA/2 IN A, SCALED AT PI/4
061565,000100: 21,3156 00006 EXTEND
061566,000101: 21,3157 71743 MP ACENTRAL # -ALPHA(2)/2 IN A,L, SCALED AT PI(2)/16)
061567,000102: 21,3160 61740 AD KCENTRAL
061568,000103: 21,3161 00006 EXTEND
061569,000104: 21,3162 63177 BZMF HUGEQUOT # K-ALPHA(2)/2 SHOULD BE PNZ FO DIVISION
061570,000105:
061571,000106: 21,3163 00006 EXTEND
061572,000107: 21,3164 40001 DCS A # ALPHA(2)/2 - K
061573,000108: 21,3165 61740 AD KCENTRAL
061574,000109: 21,3166 00006 EXTEND
061575,000110: 21,3167 11740 DV KCENTRAL # HIGH ORDER OF QUOTIENT.
061576,000111: 21,3170 57745 XCH A2CNTRAL
061577,000112: 21,3171 30001 CA L # SHIFT UP THE REMAINDER.
061578,000113: 21,3172 22007 LXCH 7 # ZERO LOW-ORDER DIVIDEND.
061579,000114: 21,3173 00006 EXTEND
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Page 1471 |
061581,000116: 21,3174 11740 DV KCENTRAL
061582,000117: 21,3175 57746 XCH A2CNTRAL +1 # QUOTIENT STORED AT 16*PI, D.P.
061583,000118: 21,3176 13202 TCF HAVEQUOT
061584,000119:
061585,000120: 21,3177 34733 HUGEQUOT CA POSMAX
061586,000121: 21,3200 54001 TS L
061587,000122: 21,3201 53746 DXCH A2CNTRAL # LIMITED QUOTIENT STORED AT 16*PI, D.P.
061588,000123:
061589,000124: 21,3202 31742 HAVEQUOT CA WCENTRAL
061590,000125: 21,3203 00006 EXTEND
061591,000126: 21,3204 74743 MP BIT9 # RESCALE OMEGA AT 16*PI IN D.P.
061592,000127: 21,3205 53742 DXCH K2CNTRAL # LOWER WORD OVERLAYS OMEGA IN WCENTRAL
061593,000128:
061594,000129: 21,3206 00006 EXTEND
061595,000130: 21,3207 31742 DCA K2CNTRAL
061596,000131: 21,3210 53751 DXCH FUNCTION
061597,000132:
061598,000133: 21,3211 31743 CA ACENTRAL # GET ALPHA*ABS(ALPHA)/(2*K)
061599,000134: 21,3212 00006 EXTEND
061600,000135: 21,3213 63217 BZMF +4
061601,000136:
061602,000137: 21,3214 00006 EXTEND
061603,000138: 21,3215 31746 DCA A2CNTRAL
061604,000139: 21,3216 13221 TCF +3
061605,000140:
061606,000141: 21,3217 00006 EXTEND
061607,000142: 21,3220 41746 DCS A2CNTRAL
061608,000143:
061609,000144: 21,3221 21751 DAS FUNCTION # OMEGA + ALPHA*ABS(ALPHA)/(2*K) AT 16*PI
061610,000145:
061611,000146: 21,3222 11750 CCS FUNCTION # DEL = +1 FOR FUNCT1 GREATER THAN ZERO.
061612,000147: 21,3223 13227 TCF POSFNCT1 # OTHERWISE DEL = -1
061613,000148: 21,3224 13226 TCF +2
061614,000149: 21,3225 13231 TCF NEGFNCT1
061615,000150:
061616,000151: 21,3226 11751 CCS FUNCTION +1 # USE LOW ORDER WORD SINCE HIGH IS ZERO
061617,000152: 21,3227 34753 POSFNCT1 CAF BIT1
061618,000153: 21,3230 13232 TCF +2
061619,000154: 21,3231 44753 NEGFNCT1 CS BIT1
061620,000155: 21,3232 55744 TS DEL
061621,000156:
061622,000157: 21,3233 11744 CCS DEL # REPLACE OMEGA BY DEL*OMEGA
061623,000158: 21,3234 13246 TCF FUNCT2 # POSITIVE DEL VALUE. PROCEED.
061624,000159: 21,3235 13237 TCF DEFUNCT
061625,000160: 21,3236 13243 TCF NEGFNCT2
061626,000161:
061627,000162: 21,3237 55741 DEFUNCT TS K2CNTRAL
061628,000163: 21,3240 55742 TS K2CNTRAL +1
061629,000164: 21,3241 13246 TCF FUNCT2
061630,000165:
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Page 1472 |
061632,000167: 21,3242 65252 NEG1/3 DEC -.33333
061633,000168:
061634,000169: 21,3243 00006 NEGFNCT2 EXTEND
061635,000170: 21,3244 41742 DCS K2CNTRAL
061636,000171: 21,3245 53742 DXCH K2CNTRAL
061637,000172:
061638,000173: 21,3246 00006 FUNCT2 EXTEND
061639,000174: 21,3247 31746 DCA A2CNTRAL
061640,000175: 21,3250 21742 DAS K2CNTRAL # DEL*OMEGA + ALPHA(2)/(2*K) AT 16*PI, D.P.
061641,000176:
061642,000177: 21,3251 31745 FUNCT3 CA A2CNTRAL
061643,000178: 21,3252 00006 EXTEND
061644,000179: 21,3253 73242 MP NEG1/3
061645,000180: 21,3254 53746 DXCH A2CNTRAL
061646,000181: 21,3255 30001 CA L
061647,000182: 21,3256 00006 EXTEND
061648,000183: 21,3257 73242 MP NEG1/3
061649,000184: 21,3260 27746 ADS A2CNTRAL +1
061650,000185: 21,3261 54001 TS L
061651,000186: 21,3262 13264 TCF +2 # A2CNTRAL NOW CONTAINS -ALPHA(2)/(6*K),
061652,000187: 21,3263 27745 ADS A2CNTRAL # SCALED AT 16*PI, IN D.P.
061653,000188:
061654,000189: 21,3264 00006 EXTEND
061655,000190: 21,3265 31742 DCA K2CNTRAL # DEL*OMEGA + ALPHA(2)/(3*K) IN A2CNTRAL,
061656,000191: 21,3266 21746 DAS A2CNTRAL # SCALED AT 16*PI, D.P.
061657,000192:
061658,000193: 21,3267 31745 CA A2CNTRAL
061659,000194: 21,3270 00006 EXTEND
061660,000195: 21,3271 71743 MP ACENTRAL
061661,000196: 21,3272 21737 DAS K2THETA
061662,000197: 21,3273 31746 CA A2CNTRAL +1
061663,000198: 21,3274 00006 EXTEND
061664,000199: 21,3275 71743 MP ACENTRAL # ACENTRAL MAY NOW BE OVERLAID.
061665,000200: 21,3276 27737 ADS K2THETA +1
061666,000201: 21,3277 54001 TS L
061667,000202: 21,3300 13302 TCF +2 # TWO TERMS OF NEGUSUM ACCUMULATED, SO FAR
061668,000203: 21,3301 27736 ADS K2THETA # SCALED AT 4*PI(2), IN D.P.
061669,000204:
061670,000205: 21,3302 31741 GETROOT CA K2CNTRAL # K*(DEL*OMEGA + ALPHA(2)/(2*K)) IS THE
061671,000206: 21,3303 00006 EXTEND # TERM FOR WHICH A SQUARE ROOT IS NEEDED.
061672,000207: 21,3304 71740 MP KCENTRAL # K AT PI/2(8)
061673,000208: 21,3305 53751 DXCH FUNCTION
061674,000209: 21,3306 31742 CA K2CNTRAL +1
061675,000210: 21,3307 00006 EXTEND
061676,000211: 21,3310 71740 MP KCENTRAL
061677,000212: 21,3311 27751 ADS FUNCTION +1
061678,000213: 21,3312 54001 TS L
061679,000214: 21,3313 13315 TCF +2
061680,000215: 21,3314 27750 ADS FUNCTION # DESIRED TERM IN FUNCTION, AT PI(2)/16
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Page 1473 |
061682,000217: 21,3315 11744 CCS DEL
061683,000218: 21,3316 13523 TCF RSTOFGTS
061684,000219: 21,3317 13565 TCF NEGUSUM
061685,000220: 21,3320 13322 TCF NEGATE
061686,000221: 21,3321 13565 TCF NEGUSUM
061687,000222:
061688,000223: 21,3322 00006 NEGATE EXTEND
061689,000224: 21,3323 41742 DCS K2CNTRAL
061690,000225: 21,3324 53742 DXCH K2CNTRAL
061691,000226: 21,3325 13523 TCF RSTOFGTS
061692,000227:
061693,000228: 16,3741 BANK 16
061694,000229: 16,3741 E6,1501 EBANK= NEGUQ
061695,000230: 16,2000 SETLOC DAPS1
061696,000231: 16,2000 BANK
061697,000232:
061698,000233: # THE WRCHN12 SUBROUTINE SETS BITS 9,10,11,12 OF CHANNEL 12 ON THE BASIS OF THE CONTENTS OF NEGUQ,NEGUR WHICH ARE
061699,000234: # THE NEGATIVES OF THE DESIRED ACCELERTION CHANGES. ACDT+C12 SETS Q(R)ACCDOT TO REFLECT TEH NEW DRIVES.
061700,000235:
061701,000236: # WARNING: ACDT+C12 AND WHCHN12 MUST BE CALLED WITH INTERRUPT INHIBITED.
061702,000237:
061703,000238: 16,3741 07400 BGIM OCTAL 07400
061704,000239: 16,3742 0066 CHNL12 EQUALS ITEMP6
061705,000240: 16,3742 41501 ACDT+C12 CS NEGUQ
061706,000241: 16,3743 00006 EXTEND # GIMBAL DRIVE REQUESTS.
061707,000242: 16,3744 71507 MP ACCDOTQ
061708,000243: 16,3745 23510 LXCH QACCDOT
061709,000244: 16,3746 41503 CS NEGUR
061710,000245: 16,3747 00006 EXTEND
061711,000246: 16,3750 71511 MP ACCDOTR
061712,000247: 16,3751 23512 LXCH RACCDOT
061713,000248:
061714,000249: 16,3752 11501 CCS NEGUQ
061715,000250: 16,3753 34742 CAF BIT10
061716,000251: 16,3754 13756 TCF +2
061717,000252: 16,3755 34743 CAF BIT9
061718,000253: 16,3756 54066 TS CHNL12
061719,000254:
061720,000255: 16,3757 11503 CCS NEGUR
061721,000256: 16,3760 34740 CAF BIT12
061722,000257: 16,3761 13763 TCF +2
061723,000258: 16,3762 34741 CAF BIT11
061724,000259: 16,3763 26066 ADS CHNL12 # (STORED RESULT NOT USED AT PRESENT)
061725,000260:
061726,000261: 16,3764 43741 CS BGIM
061727,000262: 16,3765 00006 EXTEND
061728,000263: 16,3766 02012 RAND CHAN12
061729,000264: 16,3767 60066 AD CHNL12
061730,000265: 16,3770 00006 EXTEND
061731,000266: 16,3771 01012 WRITE CHAN12
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Page 1474 |
061733,000268: 16,3772 44747 CS CALLGMBL # TURN OFF REQUEST FOR ACDT+C12 EXECUTION.
061734,000269: 16,3773 71262 MASK RCSFLAGS
061735,000270: 16,3774 55262 TS RCSFLAGS
061736,000271:
061737,000272: 16,3775 00002 TC Q # RETURN TO CALLER.
061738,000273:
061739,000274: 21,3326 BANK 21
061740,000275: 21,3326 E6,1450 EBANK= QDIFF
061741,000276: 21,2000 SETLOC DAPS4
061742,000277: 21,2000 BANK
061743,000278:
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Page 1475 |
061745,000280: # SUBROUTINE TIMEGMBL: MOD 0, OCTOBER 1967, CRAIG WORK
061746,000281:
061747,000282: # TIMEGMBL COMPUTES THE DRIVE TIME NEEDED FOR TEH TRIM GIMBAL TO POSITION THE DESCENT ENGINE NOZZLE SO AS TO NULL
061748,000283: # THE OFFSET ANGULAR ACCELERATION ABOUT THE Q (OR R) AXIS. INSTEAD OF USING AOSQ(R), TIMEBMBL USES .4*AOSQ(R),
061749,000284: # SCALED AT PI/8. FOR EACH AXIS, THE DRIVE TIME IS COMPUTED AS ABS(ALPHA/ACCDOT). AT ZERO
061750,000285: # ALPHA OR ACCDOT OR A ZERO QUOTIENT TURNS OFF THE GIMBAL DRIVE IMMEDIATELY. OTHERWISE, THE GIMBAL IS TURNED ON
061751,000286: # DRIVING IN THE CORRECT DIRECTION. THE Q(R)GIMTIMR IS SET TO TERMINATE THE DRIVE AND Q(R)ACCDOT
061752,000287: # IS STORED TO REFLECT THE NEW ACCELERATION DERIVATIVE. NEGUQ(R) WILL CONTAIN +1,+0,-1 FOR A Q(R)ACCDOT VALUE
061753,000288: # WHICH IS NEGATIVE, ZERO, OR POSITIVE.
061754,000289:
061755,000290: # INPUTS: AOSQ,AOSR, SCALED AT P1/2, AND ACCDOTQ, ACCDOTR AT PI/2(7). PI/2(7).
061756,000291:
061757,000292: # OUTPUTS: NEW GIMBAL DRIVE BITS IN CHANNEL 12, NEGUQ, NEGUR, QACCDOT, AND RACCDOT, THE LAST SCALED AT PI/2(7).
061758,000293: # Q(R)GIMTIMR WILL BE SET TO TIME AND TERMINATE GIMBAL DRIVE(S).
061759,000294:
061760,000295: # DEBRIS: A, L, Q, TEMPS 2, 3, 6, AND RUPTREG2 AND ACDT+C12 DEBRIS.
061761,000296:
061762,000297: # EXITS: VIA TC Q.
061763,000298:
061764,000299: # ALARMS, ABORTS: NONE.
061765,000300:
061766,000301: # SUBROUTINES: ACDT+C12, IBNKCALL
061767,000302:
061768,000303: # WARNING: THIS SUBROUTINE WRITES INTO CHANNEL 12 AND USES THE ITEMPS. THEREFORE IT MAY ONLY BE CALLED WITH
061769,000304: # INTERRUPT INHIBITED.
061770,000305:
061771,000306: # ERASABLE STORAGE CONFIGURATION (NEEDED BY THE INDEXING METHODS):
061772,000307: # NEGUQ ERASE +2 # NEGATIVE OF Q-AXIS GIMBAL DRIVE
061773,000308: # (SPWORD) EQUALS NEGUQ +1 # ANY S.P. ERASABLE NUMBER, NOW THRSTCMD
061774,000309: # NEGUR EQUALS NEGUQ +2 # NEGATIVE OF R-AXIS GIMBAL DRIVE
061775,000310: # ACCDOTQ ERASE +2 # Q-JERK TERM SCALED AT PI/2(7) RAD/SEC(3)
061776,000311: # (SPWORD) EQUALS ACCDOTQ +1 # ANY S.P. ERASABLE NUMBER NOW QACCDOT
061777,000312: # ACCDOTR EQUALS ACCDOTQ +2 # R-JERK TERM SCALED AT PI/2(7) RAD/SEC(3)
061778,000313: # # ACCDOTQ, ACCDOTR ARE MAGNITUDES.
061779,000314: # AOSQ ERASE +4 # Q-AXIS ACC., D.P. AT PI/2 R/SEC(2)
061780,000315: # AOSR EQUALS AOSQ +2 # R-AXIS ACCELERATION SCALED AT PI/2 R/S2
061781,000316:
061782,000317: 21,3326 0066 QRNDXER EQUALS ITEMP6
061783,000318: 21,3326 23146 OCT23146 OCTAL 23146 # DECIMAL .6
061784,000319: 21,3327 0063 NZACCDOT EQUALS ITEMP3
061785,000320:
061786,000321: 21,3327 34753 TIMEGMBL CAF ONE # INITIALZE ALLOWGTS.
061787,000322: 21,3330 55502 TS ALLOWGTS
061788,000323:
061789,000324: 21,3331 34752 CAF TWO # SET UP LOOP FOR R AXIS.
061790,000325: 21,3332 22002 LXCH Q # SAVE RETURN ADDRESS.
061791,000326: 21,3333 22071 LXCH RUPTREG2
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Page 1476 |
061793,000328: 21,3334 13336 TCF +2
061794,000329: 21,3335 34755 TIMQGMBL CAF ZERO # NOW DO THE Q-AXIS
061795,000330: 21,3336 54066 TS QRNDXER
061796,000331: 21,3337 50066 INDEX QRNDXER
061797,000332: 21,3340 31507 CA ACCDOTQ # ACCDOT IS PRESUMED TO BE AT PI/2(7).
061798,000333: 21,3341 00006 EXTEND
061799,000334: 21,3342 63412 BZMF TGOFFNOW # IS ACCDOT LESS THAN OR EQUAL TO 0?
061800,000335: 21,3343 54063 TS NZACCDOT # NO. STORE NON-ZERO, POSITIVE ACCDOT.
061801,000336:
061802,000337: 21,3344 50066 ALPHATRY INDEX QRNDXER
061803,000338: 21,3345 41536 CS AOSQ
061804,000339: 21,3346 00006 EXTEND
061805,000340: 21,3347 13412 BZF TGOFFNOW # IS ALPHA ZERO?
061806,000341:
061807,000342: 21,3350 54002 TS Q # SAVE A COPY OF -ACS.
061808,000343: 21,3351 00006 EXTEND # NO. RESCALE FOR TIMEGMBL USE.
061809,000344: 21,3352 73326 MP OCT23146 # OCTAL 23146 IS DECIMAL .6
061810,000345: 21,3353 60002 AD Q # -1.6*AOS AT PI/2 = -.4*AOS AT PI/8
061811,000346: 21,3354 54001 TS L # WAS THERE OVERFLOW?
061812,000347: 21,3355 13362 TCF SETNEGU # NO. COMPUTE DRIVE TIME.
061813,000348:
061814,000349: 21,3356 40000 CS A # RECOVER -SGN(AOS) IN THE A REGISTER.
061815,000350: 21,3357 50066 INDEX QRNDXER # YES. START DRIVE WITHOUT WAITLIST.
061816,000351: 21,3360 57501 XCH NEGUQ
061817,000352: 21,3361 13416 TCF NOTALLOW # KNOCK DOWN THE ALLOWGTS FLAG.
061818,000353:
061819,000354: 21,3362 00006 SETNEGU EXTEND
061820,000355: 21,3363 63370 BZMF POSALPH
061821,000356:
061822,000357: 21,3364 40000 COM
061823,000358: 21,3365 54062 TS ITEMP2 # STORE -ABS(.4*AOS) SCALED AT PI/8.
061824,000359: 21,3366 44753 CS BIT1
061825,000360: 21,3367 13372 TCF POSALPH +2
061826,000361: 21,3370 54062 POSALPH TS ITEMP2 # STORE -ABS(.4*AOS) SCALED AT PI/8.
061827,000362: 21,3371 34753 CA BIT1
061828,000363: 21,3372 50066 +2 INDEX QRNDXER # SGN(AOS) INTO NEGU
061829,000364: 21,3373 55501 TS NEGUQ # STORE SGN(ALPHA) AS NEGU
061830,000365:
061831,000366: 21,3374 30063 CA NZACCDOT
061832,000367: 21,3375 00006 EXTEND
061833,000368: 21,3376 74740 MP BIT12 # 2*ACCDOT, SCALED AT PI/8.
061834,000369: 21,3377 60062 AD ITEMP2 # -ABS(ALPHS) + 2*ACCDOT, AT PI/8.
061835,000370: 21,3400 00006 EXTEND
061836,000371: 21,3401 63416 BZMF NOTALLOW # IS DRIVE TIME MORE THAN TWO SECONDS?
061837,000372: 21,3402 40062 CS ITEMP2 # NO. COMPUTE DRIVE TIME.
061838,000373: 21,3403 00006 EXTEND # ABS(ALPHA) AT PI/8.
061839,000374: 21,3404 73437 MP OCT00240 # DECIMAL 10/1024
061840,000375: 21,3405 00006 EXTEND # QUOTIENT IS DRIVE TIME AT WAITLIST.
061841,000376: 21,3406 10063 DV NZACCDOT # ABS(ALPHA)/ACCDOT AT 2(14)/100
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Page 1477 |
061843,000378: 21,3407 00006 EXTEND
061844,000379: 21,3410 13412 BZF TGOFFNOW # DRIVE TIME MUST BE GREATER THAN ZERO.
061845,000380:
061846,000381: 21,3411 13424 TCF DRIVEON
061847,000382:
061848,000383: 21,3412 34755 TGOFFNOW CAF ZERO # TURN OFF GIMBAL NOW.
061849,000384: 21,3413 50066 INDEX QRNDXER
061850,000385: 21,3414 55501 TS NEGUQ
061851,000386:
061852,000387: 21,3415 13426 TCF DONEYET
061853,000388:
061854,000389: 21,3416 36010 NOTALLOW CAF OCT31
061855,000390: 21,3417 50066 INDEX QRNDXER
061856,000391: 21,3420 55631 TS QGIMTIMR
061857,000392: 21,3421 34755 CAF ZERO # DRIVE TIME IS MORE THAN 2 SECONDS, SO
061858,000393: 21,3422 55502 TS ALLOWGTS # DO NOT PERMIT FURTHER GTS ATTITUDE-RATE
061859,000394: # CONTROL UNTIL AOSTASK APPROVES.
061860,000395: 21,3423 13426 TCF DONEYET # NO WAITLIST CALL IS MADE.
061861,000396:
061862,000397: 21,3424 50066 DRIVEON INDEX QRNDXER
061863,000398: 21,3425 55631 TS QGIMTIMR # CHOOSE Q OR R AXIS.
061864,000399:
061865,000400: 21,3426 10066 DONEYET CCS QRNDXER
061866,000401: 21,3427 13335 TCF TIMQGMBL
061867,000402:
061868,000403: 21,3430 52073 DXCH RUPTREG3 # PROTECT IBNKCALL ERASABLES. ACDT+C12
061869,000404: 21,3431 52063 DXCH ITEMP2 # LEAVES ITEMPS2,3 ALONE.
061870,000405:
061871,000406: 21,3432 04674 TC IBNKCALL # TURN OFF CHANNEL BITS, SET Q(R)ACCDOTS.
061872,000407: 21,3433 35742 CADR ACDT+C12
061873,000408:
061874,000409: 21,3434 52063 DXCH ITEMP2 # RESTORE ERASABLES FOR IBNKCALL.
061875,000410: 21,3435 52073 DXCH RUPTREG3
061876,000411:
061877,000412: 21,3436 00071 TC RUPTREG2 # RETURN TO CALLER.
061878,000413:
061879,000414: 21,3437 00240 OCT00240 OCTAL 00240 # DECIMAL 10/1024
061880,000415:
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Page 1478 |
061882,000417: # THE FOLLOWING SECTION IS A CONTINUATION OF THE TRIM GIMBAL CONTROL FROM THE LAST GTS ENTRY. THE QUANTITY NEGUSUM
061883,000418: # IS COMPUTED FOR EACH AXIS (Q,R), .707*DEL*FUNCTION(3/2) + K2THETA = NEGUSUM. NEW DRIVES ARE ENTERED TO CH 12.
061884,000419:
061885,000420: # THE SUBROUTIEN GTSQRT ACCEPTS A DOUBLE PRECISION VALUE IN FUNCTION, FUNCTION +1 AND RETURNS A SINGLE-PRECISION
061886,000421: # SQUARE ROOT OF THE FOURTEEN MOST SIGNIFICATN BITS OF THE ARGUMENT. ALSO, TEH CELL SHFTFLAG CONTAINS A BINARY
061887,000422: # EXPONENT S, SUCH THAT THE SQUARE ROOT (RETURNED IN THE A REGISTER) MUST BE SHIFTED RIGHT (MULTIPLIED BY 2 TO THE
061888,000423: # POWER (-S)) IN ORDER TO BE THE TRUE SQUARE ROOT OF TEH FOURTEEN MOST SIGNIFICANT BITS OF FUNCTION, FUNCTION +1.
061889,000424: # SQUARE ROOT ERROR IS NOT MORE THAN 2 IN THE 14TH SIGNIFICANT BIT. CELLS CLOBBERED ARE A, L, SHFTFLAG, ININDEX,
061890,000425: # HALFARG, SCRATCH, SR, FUNCTION, FUNCTION +1. GTSQRT IS CALLED BY TC GTSQRT AND RETURNS VIA TC Q OR TC FUNCTION +1.
061891,000426: # ZERO OR NEGATIVE ARGUMENTS YIELD ZERO FOR SQUARE ROOTS.
061892,000427:
061893,000428: 21,3440 11750 GTSQRT CCS FUNCTION
061894,000429: 21,3441 13457 TCF GOODARG # FUNCTION IS POSITIVE. TAKE SQUARE ROOT.
061895,000430: 21,3442 13444 TCF +2 # HIGH ORDER WORD IS ZERO. TRY THE LOWER.
061896,000431: 21,3443 13450 TCF ZEROOT
061897,000432:
061898,000433: 21,3444 31751 CA FUNCTION +1
061899,000434: 21,3445 00006 EXTEND
061900,000435: 21,3446 63450 BZMF ZEROOT
061901,000436:
061902,000437: 21,3447 13453 TCF ZEROHIGH # PROCEED.
061903,000438: 21,3450 34755 ZEROOT CA ZERO
061904,000439: 21,3451 55740 TS SHFTFLAG
061905,000440: 21,3452 00002 TC Q
061906,000441:
061907,000442: 21,3453 57750 ZEROHIGH XCH FUNCTION # 14 MOST SIGNIFICANT BITS ARE IN THE
061908,000443: 21,3454 57751 XCH FUNCTION +1 # LOWER WORD. EXCHANGE THEM.
061909,000444: 21,3455 34757 CA SEVEN
061910,000445: 21,3456 13460 TCF GOODARG +1
061911,000446:
061912,000447: 21,3457 34755 GOODARG CA ZERO
061913,000448: 21,3460 55740 TS SHFTFLAG
061914,000449: 21,3461 35741 CA TWELVE # INITIALIZE THE SCALING LOOP.
061915,000450: 21,3462 55743 TS ININDEX
061916,000451: 21,3463 13472 TCF SCALLOOP
061917,000452:
061918,000453: 21,3464 31750 SCALSTRT CA FUNCTION
061919,000454: 21,3465 13506 TCF SCALDONE
061920,000455:
061921,000456: 21,3466 37751 MULBUSH CA NEG2 # IF ARG IS NOT LESS THAN 1/4, INDEX IS
061922,000457: 21,3467 27743 ADS ININDEX # ZERO, INDICATING NO SHIFT NEEDED.
061923,000458: 21,3470 00006 EXTEND # BRANCH IF ARG IS NOT LESS THAN 1/4.
061924,000459: 21,3471 63464 BZMF SCALSTRT # OTHERWISE COMPARE ARG WITH A REFERENCE
061925,000460: # WHICH IS 4 TIMES LARGER THAN THE LAST.
061926,000461: 21,3472 41750 SCALLOOP CS FUNCTION
061927,000462: 21,3473 51743 INDEX ININDEX
061928,000463: 21,3474 64735 AD BIT15 # REFERENCE MAGNITUDE LESS OR EQUAL TO 1/4
061929,000464: 21,3475 00006 EXTEND
061930,000465: 21,3476 63466 BZMF MULBUSH # IF ARG IS NOT LESS THAN REFERENCE, GO
061931,000466: # AROUND THE MULBERRY BUSH ONCE MORE.
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Page 1479 |
061933,000468: 21,3477 51743 INDEX ININDEX
061934,000469: 21,3500 34735 CA BIT15 # THIS IS THE SCALE MAGNITUDE
061935,000470: 21,3501 57746 XCH HALFARG # 2**(-ININDEX) IS THE SHIFT DIVISOR.
061936,000471: 21,3502 00006 EXTEND # RESCALE ARGUMENT.
061937,000472: 21,3503 31751 DCA FUNCTION
061938,000473: 21,3504 00006 EXTEND
061939,000474: 21,3505 11746 DV HALFARG
061940,000475: # ININDEX AND SHFTFLAG PRESERVE INFO FOR
061941,000476: # RESCALING AFTER ROOT PROCESS.
061942,000477: 21,3506 00006 SCALDONE EXTEND
061943,000478: 21,3507 23751 QXCH FUNCTION +1 # SAVE Q FOR RETURN
061944,000479: 21,3510 00006 EXTEND
061945,000480: 21,3511 74736 MP BIT14
061946,000481: 21,3512 55746 TS HALFARG
061947,000482: 21,3513 74737 MASK BIT13
061948,000483: 21,3514 10000 CCS A
061949,000484: 21,3515 33633 CA OCT11276
061950,000485: 21,3516 63631 AD ROOTHALF # INITIAL GUESS IS ROOT 1/2 OR POSMAX
061951,000486: 21,3517 03635 TC ROOTCYCL
061952,000487: 21,3520 03635 TC ROOTCYCL
061953,000488: 21,3521 03635 TC ROOTCYCL
061954,000489: 21,3522 01751 TC FUNCTION +1
061955,000490:
061956,000491: # ***************************************************************************
061957,000492:
061958,000493: 21,3523 03440 RSTOFGTS TC GTSQRT
061959,000494: 21,3524 57741 PRODUCT XCH K2CNTRAL
061960,000495: 21,3525 00006 EXTEND
061961,000496: 21,3526 71741 MP K2CNTRAL
061962,000497: 21,3527 53742 DXCH K2CNTRAL
061963,000498: 21,3530 00006 EXTEND # THE PRODUCT OF
061964,000499: 21,3531 70001 MP L # 1/2 2 1/2
061965,000500: 21,3532 27742 ADS K2CNTRAL +1 # K *(DEL*OMEGA + ALPHA /(2*K))
061966,000501: 21,3533 54001 TS L # AND
061967,000502: 21,3534 13536 TCF +2 # 2
061968,000503: 21,3535 27741 ADS K2CNTRAL # DEL*(DEL*OMEGA + ALPHA /(2*K)) NOW IN K2CNTRAL
061969,000504:
061970,000505: 21,3536 31743 DOSHIFT CA ININDEX
061971,000506: 21,3537 00006 EXTEND # MULTIPLY IN THE FACTOR 2(-S), RETURNED
061972,000507: 21,3540 74736 MP BIT14 # BY THE GTSQRT SUBROUTINE
061973,000508: 21,3541 27740 ADS SHFTFLAG
061974,000509: 21,3542 00006 EXTEND
061975,000510: 21,3543 13562 BZF ADDITIN
061976,000511: 21,3544 51740 INDEX SHFTFLAG
061977,000512: 21,3545 34735 CA BIT15
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Page 1480 |
061979,000514: 21,3546 57741 XCH K2CNTRAL
061980,000515: 21,3547 00006 EXTEND
061981,000516: 21,3550 71741 MP K2CNTRAL
061982,000517: 21,3551 21737 DAS K2THETA
061983,000518: 21,3552 57741 XCH K2CNTRAL
061984,000519: 21,3553 00006 EXTEND
061985,000520: 21,3554 71742 MP K2CNTRAL +1
061986,000521: 21,3555 27737 ADS K2THETA +1
061987,000522: 21,3556 54001 TS L
061988,000523: 21,3557 13561 TCF +2
061989,000524: 21,3560 27736 ADS K2THETA
061990,000525:
061991,000526: 21,3561 13565 TCF NEGUSUM
061992,000527:
061993,000528: 21,3562 00006 ADDITIN EXTEND
061994,000529: 21,3563 31742 DCA K2CNTRAL
061995,000530: 21,3564 21737 DAS K2THETA # NO ADD IN THE K2THETA TERM.
061996,000531: 21,3565 11736 NEGUSUM CCS K2THETA # TEST SIGN OF HIGH ORDER PART.
061997,000532: 21,3566 13572 TCF NEGDRIVE
061998,000533: 21,3567 13571 TCF +2
061999,000534: 21,3570 13574 TCF POSDRIVE
062000,000535:
062001,000536: 21,3571 11737 CCS K2THETA +1 # SIGN TEST FOR LOW ORDER PART.
062002,000537: 21,3572 34753 NEGDRIVE CA BIT1
062003,000538: 21,3573 13575 TCF +2 # STOP GIMBAL DRIVE FOR A ZERO NEGUSUM.
062004,000539: 21,3574 44753 POSDRIVE CS BIT1
062005,000540: 21,3575 54001 TS L # SAVE FOR DRIVE REVERSAL TEST.
062006,000541: 21,3576 51747 INDEX QRCNTR
062007,000542: 21,3577 57501 XCH NEGUQ
062008,000543:
062009,000544: 21,3600 00006 EXTEND
062010,000545: 21,3601 70001 MP L # MULTIPLY OLD NEGU AND NEW NEGU.
062011,000546: 21,3602 10001 CCS L
062012,000547: 21,3603 13620 TCF LOUPE # NON-ZERO GIMBAL DRIVE BEING CONTINUED.
062013,000548:
062014,000549: 21,3604 13615 TCF ZEROLOUP # NO REVERSAL PROBLEM HERE.
062015,000550:
062016,000551: 21,3605 13607 TCF REVERSAL # NON-ZERO GIMBAL DRIVE BEING REVERSED.
062017,000552: 21,3606 13615 TCF ZEROLOUP # NO REVERSAL PROBLEM HERE.
062018,000553:
062019,000554: 21,3607 51747 REVERSAL INDEX QRCNTR # A ZERO-DRIVE PAUSE IS NEEDED HERE. ZERO
062020,000555: 21,3610 55510 TS QACCDOT # IS IN A REGISTER FROM CCS ON (-1).
062021,000556: 21,3611 51747 INDEX QRCNTR
062022,000557: 21,3612 43632 CS GMBLBITA
062023,000558: 21,3613 00006 EXTEND
062024,000559: 21,3614 03012 WAND CHAN12
062025,000560:
062026,000561: 21,3615 41262 ZEROLOUP CS RCSFLAGS # SET UP REQUEST FOR ACDT+C12 CALL.
062027,000562: 21,3616 74747 MASK CALLGMBL
062028,000563: 21,3617 27262 ADS RCSFLAGS
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Page 1481 |
062030,000565: 21,3620 11747 LOUPE CCS QRCNTR # HAVE BOTH AXES BEEN PROCESSED?
062031,000566: 21,3621 13114 TCF GOQTRIMG # NO. DO Q AXIS NEXT.
062032,000567:
062033,000568: 21,3622 31505 CA SAVESR # RESTORE THE SR
062034,000569: 21,3623 54021 TS SR
062035,000570:
062036,000571: 21,3624 00006 GOCLOSE EXTEND # TERMINATE THE JASK.
062037,000572: 21,3625 33630 DCA CLOSEADR
062038,000573: 21,3626 52006 DTCB
062039,000574:
062040,000575: 21,3627 E6,1536 EBANK= AOSQ
062041,000576: 21,3627 03270 36106 CLOSEADR 2CADR CLOSEOUT # TERMINATE THE JASK.
062042,000577:
062043,000578: 21,3631 5741 TWELVE EQUALS OCT14
062044,000579: 21,3631 26501 ROOTHALF OCTAL 26501 # SQUARE ROOT OF 1/2
062045,000580: 21,3632 01400 GMBLBITA OCTAL 01400 # INDEXED WRT GMBLBITB DO NOT MOVE *******
062046,000581: 21,3633 11276 OCT11276 OCTAL 11276 # POSMAX -- ROOTHALF
062047,000582: 21,3634 06000 GMBLBITB OCTAL 06000 # INDEXED WRT GMBLBITA DO NOT MOVE *******
062048,000583:
062049,000584: # SUBROUTINE ROOTCYCL: BY CRAIG WORK, 3 APRIL 68
062050,000585:
062051,000586: # ROOTCYCL IS A SUBROUTINE WHICH EXECUTS ONE NEWTON SQUARE ALGORITHM ITERATION. THE INITIAL GUESS AT THE
062052,000587: # SQUARE ROOT IS PRESUMED TO BE IN THE A REGISTER AND ONE-HALF THE SQUARE IS TAKEN FROM HALFARG. THE NEW APPROXIMATION
062053,000588: # TO THE SQUARE ROOT IS RETURNED IN THE A REGISTER. DEBRIS: A, L, SR, SCRATCH. ROOTCYCL IS CALLED FROM
062054,000589: # LOCATION (LOC) BY A TC ROOTCYCL, AND RETURNS (TC Q) TO LOC +1.
062055,000590:
062056,000591: # WARNING: IF THE INITIAL GUESS IS NOT GREATER THAN THE SQUARE, DIVIDE OR ADD OVERFLOW IS A REAL POSSIBILITY.
062057,000592:
062058,000593: 21,3635 55745 ROOTCYCL TS SCRATCH # STORE X
062059,000594: 21,3636 54021 TS SR # X/2 NOW IN SR
062060,000595: 21,3637 31746 CA HALFARG # ARG/2 IN THE A REG
062061,000596: 21,3640 22007 ZL # PREPARE FOR DIVISION
062062,000597: 21,3641 00006 EXTEND
062063,000598: 21,3642 11745 DV SCRATCH # (ARG/X)/2
062064,000599: 21,3643 60021 AD SR # (X + ARG/X)/2 IN THE A REG
062065,000600: 21,3644 00002 TC Q
062066,000601:
062067,000602:
End of include-file TRIM_GIMBAL_CNTROL_SYSTEM.agc. Parent file is MAIN.agc