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. |
020292,000002: ## Copyright: Public domain.
020293,000003: ## Filename: R60_R62.agc
020294,000004: ## Purpose: Part of the source code for Luminary 1A build 099.
020295,000005: ## It is part of the source code for the Lunar Module's (LM)
020296,000006: ## Apollo Guidance Computer (AGC), for Apollo 11.
020297,000007: ## Assembler: yaYUL
020298,000008: ## Contact: Ron Burkey <info@sandroid.org>.
020299,000009: ## Website: www.ibiblio.org/apollo.
020300,000010: ## Pages: 472-485
020301,000011: ## Mod history: 2009-05-17 RSB Adapted from the corresponding
020302,000012: ## Luminary131 file, using page
020303,000013: ## images from Luminary 1A.
020304,000014: ## 2016-12-13 RSB GOTOP00H -> GOTOPOOH
020305,000015: ## 2016-12-14 RSB Proofed text comments with octopus/ProoferComments
020306,000016: ## and corrected the errors found.
020307,000017: ## 2017-01-27 RSB Back-ported a comment-text fix identified in Luminary 69.
020308,000018: ## 2017-03-09 RSB Comment text fixes noted in proofing Luminary 116.
020309,000019:
020310,000020: ## This source code has been transcribed or otherwise adapted from
020311,000021: ## digitized images of a hardcopy from the MIT Museum. The digitization
020312,000022: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
020313,000023: ## the Museum. Many thanks to both. The images (with suitable reduction
020314,000024: ## in storage size and consequent reduction in image quality as well) are
020315,000025: ## available online at www.ibiblio.org/apollo. If for some reason you
020316,000026: ## find that the images are illegible, contact me at info@sandroid.org
020317,000027: ## about getting access to the (much) higher-quality images which Paul
020318,000028: ## actually created.
020319,000029: ##
020320,000030: ## Notations on the hardcopy document read, in part:
020321,000031: ##
020322,000032: ## Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
020323,000033: ## 16:27 JULY 14, 1969
020324,000034:
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Page 472 |
020326,000036: # MOD NO: 0 DATE: 1 MAY 1968
020327,000037: # MOD BY: DIGITAL DEVEL GROUP LOG SECTION R60,R62
020328,000038:
020329,000039: # FUNCTIONAL DESCRIPTION:
020330,000040:
020331,000041: # CALLED AS A GENERAL SUBROUTINE TO MANEUVER THE LM TO A SPECIFIED
020332,000042: # ATTITUDE.
020333,000043:
020334,000044: # 1. IF THE 3-AXIS FLAG IS NOT SET THE FINAL CDU ANGLES ARE
020335,000045: # CALCULATED (VECPOINT).
020336,000046:
020337,000047: # 2. THE FDAI BALL ANGLES (NOUN 18) ARE CALCULATED (BALLANGS).
020338,000048:
020339,000049: # 3. REQUEST FLASHING DISPLAY V50 N18 PLEASE PERFORM AUTO MANEUVER.
020340,000050:
020341,000051: # 4. IF PRIORITY DISPLAY FLAG IS SET DO A PHASECHANGE. THEN AWAIT
020342,000052: # ASTRONAUT RESPONSE.
020343,000053:
020344,000054: # 5. DISPLAY RESPONSE RETURNS:
020345,000055:
020346,000056: # A. ENTER - RESET 3-AXIS FLAG AND RETURN TO CLIENT.
020347,000057:
020348,000058: # B. TERMINATE - IF IN P00 GO TO STEP 5A. OTHERWISE CHECK IF R61 IS
020349,000059: # THE CALLING PROGRAM. IF IN R61 AN EXIT IS MADE TO GOTOV56. IF
020350,000060: # NOT IN R61 AN EXIT IS DONE VIA GOTOP00H.
020351,000061:
020352,000062: # C. PROCEED - CONTINUE WITH PROGRAM AT STEP 6.
020353,000063:
020354,000064: # 6. IF THE 3-AXISFLAG IS NOT SET, THE FINAL CDU ANGLES ARE CALCULATED
020355,000065: # (VECPOINT).
020356,000066:
020357,000067: # 7. THE FDAI BALL ANGLES (NOUN 18) ARE CALCULATED (BALLANGS).
020358,000068:
020359,000069: # 8. IF THE G+N SWITCH IS NOT SET GO BACK TO STEP 3.
020360,000070: #
020361,000071: # 9. IF THE AUTO SWITCH IS NOT SET GO BACK TO STEP 3.
020362,000072:
020363,000073: # 10. NONFLASHING DISPLAY V06N18 (FDAI ANGLES).
020364,000074:
020365,000075: # 11. DO A PHASECHANGE.
020366,000076:
020367,000077: # 12. DO A MANEUVER CALCULATION AND ICDU DRIVE ROUTINE TO ACHIEVE FINAL
020368,000078: # GIMBAL ANGLES (GOMANUR).
020369,000079:
020370,000080: # 13. AT END OF MANEUVER GO TO STEP 3.
020371,000081:
020372,000082: # IF SATISFACTORY MANEUVER STEP 5A EXITS R60.
020373,000083: # FOR FURTHER ADJUSTMENT OF THE VEHICLE ATTITUDE ABOUT THE
020374,000084: # DESIRED VECTOR, THE ROUTINE MAY BE PERFORMED AGAIN STARTING AT
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Page 473 |
020376,000086: # STEP 5C.
020377,000087:
020378,000088: # CALLING SEQUENCE: TC BANKCALL
020379,000089: # CADR R60LEM
020380,000090:
020381,000091: # ERASABLE INITIALIZATION REQUIRED: SCAXIS, POINTVSM (FOR VECPOINT)
020382,000092: # 3AXISFLG.
020383,000093:
020384,000094: # SUBROUTINES CALLED: VECPOINT, BALLANGS, GOPERF2R, LINUS, GODSPER,
020385,000095: # GOMANUR, DOWNFLAG, PHASCHNG, UPFLAG
020386,000096:
020387,000097: # NORMAL EXIT MODES: CAE TEMPR60 (CALLERS RETURN ADDRESS)
020388,000098: # TC BANKJUMP
020389,000099:
020390,000100: # ALARMS: NONE
020391,000101:
020392,000102: # OUTPUT: NONE
020393,000103:
020394,000104: # DEBRIS: CPHI, CTHETA, CPSI, 3AXISFLG, TBASE2
020395,000105:
020396,000106: 34,2000 BANK 34
020397,000107: 26,2000 SETLOC MANUVER
020398,000108: 26,2000 BANK
020399,000109:
020400,000110: 26,2123 1164 EBANK= TEMPR60
020401,000111:
020402,000112: 26,2123 COUNT* $$/R06
020403,000113: 26,2123 04645 R60LEM TC MAKECADR
020404,000114: 26,2124 55164 TS TEMPR60
020405,000115:
020406,000116: 26,2125 34746 REDOMANN CAF 3AXISBIT
020407,000117: 26,2126 70101 MASK FLAGWRD5 # IS 3-AXIS FLAG SET
020408,000118: 26,2127 10000 CCS A
020409,000119: 26,2130 12136 TCF TOBALL # YES
020410,000120: 26,2131 06037 TC INTPRET
020411,000121: 26,2132 77624 CALL
020412,000122: 26,2133 56040 VECPOINT # TO COMPUTE FINAL ANGLES
020413,000123: 26,2134 00322 STORE CPHI # STORE FINAL ANGLES - CPHI, CTHETA, CPSI
020414,000124: 26,2135 77776 EXIT
020415,000125:
020416,000126: 26,2136 04616 TOBALL TC BANKCALL
020417,000127: 26,2137 54266 CADR BALLANGS # TO CONVERT ANGLES TO FDAI
020418,000128: 26,2140 32254 TOBALLA CAF V06N18
020419,000129: 26,2141 04616 TC BANKCALL
020420,000130: 26,2142 20710 CADR GOPERF2R # DISPLAY PLEASE PERFORM AUTO MANEUVER
020421,000131: 26,2143 02242 TC R61TEST
020422,000132: 26,2144 02150 TC REDOMANC # PROCEED
020423,000133: 26,2145 02175 TC ENDMANU1 # ENTER I.E. FINISHED WITH R60
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Page 474 |
020425,000135: 26,2146 02201 TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
020426,000136: 26,2147 05155 TC ENDOFJOB
020427,000137:
020428,000138: 26,2150 34746 REDOMANC CAF 3AXISBIT
020429,000139: 26,2151 70101 MASK FLAGWRD5 # IS 3-AXIS FLAG SET
020430,000140: 26,2152 10000 CCS A
020431,000141: 26,2153 12161 TCF TOBALLC # YES
020432,000142: 26,2154 06037 TC INTPRET
020433,000143: 26,2155 77624 CALL
020434,000144: 26,2156 56040 VECPOINT # TO COMPUTE FINAL ANGLES
020435,000145: 26,2157 00322 STORE CPHI # STORE ANGLES
020436,000146: 26,2160 77776 EXIT
020437,000147:
020438,000148: 26,2161 04616 TOBALLC TC BANKCALL
020439,000149: 26,2162 54266 CADR BALLANGS # TO CONVERT ANGLES TO FDAI
020440,000150: 26,2163 02255 TC G+N,AUTO # CHECK AUTO MODE
020441,000151: 26,2164 10000 CCS A
020442,000152: 26,2165 12140 TCF TOBALLA # NOT AUTO, GO REREQUEST AUTO MANEUVER.
020443,000153:
020444,000154: 26,2166 32254 AUTOMANV CAF V06N18 # STATIC DISPLAY DURING AUTO MANEUVER
020445,000155: 26,2167 04616 TC BANKCALL # -
020446,000156: 26,2170 20451 CADR GODSPR # -
020447,000157: 26,2171 02201 TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
020448,000158:
020449,000159: 26,2172 04616 STARTMNV TC BANKCALL # PERFORM MANEUVER VIA KALCMANU
020450,000160: 26,2173 17750 CADR GOMANUR
020451,000161:
020452,000162: 26,2174 12140 ENDMANUV TCF TOBALLA # FINISHED MANEUVER.
020453,000163: 26,2175 05516 ENDMANU1 TC DOWNFLAG # RESET 3-AXIS FLAG
020454,000164: 26,2176 00124 ADRES 3AXISFLG
020455,000165: 26,2177 31164 CAE TEMPR60 # -
020456,000166: 26,2200 04640 TC BANKJUMP # -
020457,000167:
020458,000168: 26,2201 40100 CHKLINUS CS FLAGWRD4
020459,000169: 26,2202 74740 MASK PDSPFBIT # IS PRIORITY DISPLAY FLAG SET?
020460,000170: 26,2203 10000 CCS A # -
020461,000171: 26,2204 00002 TC Q # NO - EXIT
020462,000172: 26,2205 30002 CA Q
020463,000173: 26,2206 54156 TS MPAC +2 # SAVE RETURN
020464,000174: 26,2207 46245 CS THREE # OBTAIN LOCATION FOR RESTART
020465,000175: 26,2210 60133 AD BUF2 # HOLDS Q OF LAST DISPLAY
020466,000176: 26,2211 55055 TS TBASE2
020467,000177:
020468,000178: 26,2212 05353 TC PHASCHNG
020469,000179: 26,2213 00132 OCT 00132
020470,000180:
020471,000181: 26,2214 34745 CAF BIT7
020472,000182: 26,2215 05464 TC LINUS # GO SET BITS FOR PRIORITY DISPLAY -
020473,000183: 26,2216 00156 TC MPAC +2
020474,000184:
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Page 475 |
020476,000186: 26,2217 37714 RELINUS CAF PRIO26 # RESTORE ORIGINAL PRIORITY
020477,000187: 26,2220 05146 TC PRIOCHNG
020478,000188:
020479,000189: 26,2221 34747 CAF TRACKBIT # DON'T CONTINUE R60 UNLESS TRACKFLAG ON.
020480,000190: 26,2222 70075 MASK FLAGWRD1
020481,000191: 26,2223 10000 CCS A
020482,000192: 26,2224 12237 TCF RER60
020483,000193:
020484,000194: 26,2225 34745 CAF RNDVZBIT # IS IT P20?
020485,000195: 26,2226 70074 MASK FLAGWRD0
020486,000196: 26,2227 10000 CCS A
020487,000197: 26,2230 02234 TC +4 # YES
020488,000198: 26,2231 05353 TC PHASCHNG # NO, MUST BE P25, SET 2.11 SPOT
020489,000199: 26,2232 40112 OCT 40112
020490,000200:
020491,000201: 26,2233 05155 TC ENDOFJOB
020492,000202:
020493,000203: 26,2234 05353 TC PHASCHNG # SET 2.7 SPOT FOR P20
020494,000204: 26,2235 40072 OCT 40072
020495,000205:
020496,000206: 26,2236 05155 TC ENDOFJOB
020497,000207:
020498,000208: 26,2237 05504 RER60 TC UPFLAG # SET PRIO DISPLAY FLAG AFTER RESTART
020499,000209: 26,2240 00077 ADRES PDSPFLAG
020500,000210:
020501,000211: 26,2241 01055 TC TBASE2
020502,000212:
020503,000213: 26,2242 31011 R61TEST CA MODREG # IF WE ARE IN P00 IT MUST BE V49 OR V89
020504,000214: 26,2243 00006 EXTEND
020505,000215: 26,2244 12175 BZF ENDMANU1 # THUS WE GO TO ENDEXT VIA USER
020506,000216:
020507,000217: 26,2245 30100 CA FLAGWRD4 # ARE WE IN R61 (P20 OR P25)
020508,000218: 26,2246 74740 MASK PDSPFBIT
020509,000219: 26,2247 00006 EXTEND
020510,000220: 26,2250 16001 BZF GOTOPOOH # NO
020511,000221: 26,2251 06022 TC GOTOV56 # YES
020512,000222:
020513,000223: 26,2252 20100 BIT14+7 OCT 20100 # -
020514,000224: 26,2253 00203 OCT203 OCT 203
020515,000225: 26,2254 01422 V06N18 VN 0618
020516,000226:
020517,000227: # SUBROUTINE TO CHECK FOR G+N CONTROL, AUTO STABILIZATION
020518,000228:
020519,000229: # RETURNS WITH C(A) = + IF NOT SET FOR G+N, AUTO
020520,000230: # RETURNS WITH C(A) = +0 IF SWITCHES ARE SET
020521,000231:
020522,000232: 26,2255 00006 G+N,AUTO EXTEND
020523,000233: 26,2256 00030 READ CHAN30
020524,000234: 26,2257 74742 MASK BIT10
020525,000235: 26,2260 10000 CCS A
020526,000236: 26,2261 00002 TC Q # NOT IN G+N C(A) = +
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Page 476 |
020528,000238: 26,2262 00006 ISITAUTO EXTEND # CHECK FOR AUTO MODE
020529,000239: 26,2263 00031 READ CHAN31
020530,000240: 26,2264 74736 MASK BIT14
020531,000241: 26,2265 00002 TC Q # (+) = NOT IN AUTO, (+0) = AOK
020532,000242:
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Page 477 |
020534,000244: # PROGRAM DESCRIPTION BALLANGS
020535,000245: # MOD NO. LOG SECTION R60,R62
020536,000246:
020537,000247: # WRITTEN BY RAMA M. AIYAWAR
020538,000248:
020539,000249: # FUNCTIONAL DESCRIPTION
020540,000250:
020541,000251: # COMPUTES LM FDAI BALL DISPLAY ANGLES
020542,000252:
020543,000253: # CALLING SEQUENCE
020544,000254:
020545,000255: # TC BALLANGS
020546,000256:
020547,000257: # NORMAL EXIT MODE
020548,000258:
020549,000259: # TC BALLEXIT (SAVED Q)
020550,000260:
020551,000261: # ALARM OR EXIT MODE NIL
020552,000262:
020553,000263: # SUBROUTINES CALLED
020554,000264:
020555,000265: # CD*TR*G
020556,000266: # ARCTAN
020557,000267:
020558,000268: # INPUT
020559,000269:
020560,000270: # CPHI,CTHETA,CPSI ARE THE ANGLES CORRESPONDING TO AOG, AIG, AMG. THEY ARE
020561,000271: # SP,2S COMPLIMENT SCALED TO HALF REVOLUTION.
020562,000272:
020563,000273: # OUTPUT
020564,000274:
020565,000275: # FDAIX, FDAIY, FDAIZ ARE THE REQUIRED BALL ANGLES SCALED TO HALF REVOLUTION
020566,000276: # SP,2S COMPLIMENT.
020567,000277:
020568,000278: # THESE ANGLES WILL BE DISPLAYED AS DEGREES AND HUNDREDTHS, IN THE ORDER ROLL, PITCH, YAW, USING NOUNS 18 & 19.
020569,000279:
020570,000280: # ERASABLE INITIALIZATION REQUIRED
020571,000281:
020572,000282: # CPHI, CTHETA, CPSI EACH A SP REGISTER
020573,000283:
020574,000284: # DEBRIS
020575,000285:
020576,000286: # A,L,Q,MPAC,SINCDU,COSCDU,PUSHLIST,BALLEXIT
020577,000287:
020578,000288: # NOMENCLATURE: CPHI, CTHETA, & CPSI REPRESENT THE OUTER, INNER, & MIDDLE GIMBAL ANGLES, RESPECTIVELY; OR
020579,000289: # EQUIVALENTLY, CDUX, CDUY, & CDUZ.
020580,000290:
020581,000291: # NOTE: ARCTAN CHECKS FOR OVERFLOW AND SHOULD BE ABLE TO HANDLE ANY SINGULARITIES.
020582,000292:
020583,000293: 26,2000 SETLOC BAWLANGS
020584,000294: 26,2000 BANK
020585,000295:
020586,000296: 26,2266 COUNT* $$/BALL
020587,000297: 26,2266 04645 BALLANGS TC MAKECADR
020588,000298: 26,2267 55342 TS BALLEXIT
020589,000299: 26,2270 30321 CA CPHI
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Page 478 |
020591,000301: 26,2271 54772 TS CDUSPOT +4
020592,000302: 26,2272 30322 CA CTHETA
020593,000303: 26,2273 54766 TS CDUSPOT
020594,000304: 26,2274 30323 CA CPSI
020595,000305: 26,2275 54770 TS CDUSPOT +2
020596,000306:
020597,000307: 26,2276 06037 TC INTPRET
020598,000308: 26,2277 45001 SETPD CALL
020599,000309: 26,2300 00001 0D
020600,000310: 26,2301 47543 CD*TR*G
020601,000311:
020602,000312: 26,2302 41345 DLOAD DMP
020603,000313: 26,2303 00743 SINCDUX # SIN (OGA)
020604,000314: 26,2304 00747 COSCDUZ # COS (MGA)
020605,000315:
020606,000316: 26,2305 57552 SL1 DCOMP # SCALE
020607,000317: 26,2306 65336 ARCSIN PDDL # YAW = ARCSIN(-SXCZ) INTO 0 PD
020608,000318: 26,2307 00741 SINCDUZ
020609,000319: 26,2310 14023 STODL SINTH # (SINTH = 18D IN PD)
020610,000320: 26,2311 00747 COSCDUZ
020611,000321: 26,2312 72405 DMP SL1 # RESCALE
020612,000322: 26,2313 00751 COSCDUX
020613,000323: 26,2314 34021 STCALL COSTH # (COSTH = 16D IN PD)
020614,000324: 26,2315 26510 ARCTAN
020615,000325: 26,2316 41325 PDDL DMP # ROLL = ARCTAN(SZ/CZCX) INTO 2 PD
020616,000326: 26,2317 00741 SINCDUZ
020617,000327: 26,2320 00743 SINCDUX
020618,000328: 26,2321 41512 SL2 PUSH # SXSZ INTO 4 PD
020619,000329: 26,2322 65205 DMP PDDL # SXSZCY INTO 4 PD
020620,000330: 26,2323 00745 COSCDUY
020621,000331: 26,2324 65205 DMP PDDL # SXSZSY INTO 6 PD
020622,000332: 26,2325 00737 SINCDUY
020623,000333: 26,2326 00751 COSCDUX
020624,000334: 26,2327 72405 DMP SL1 # CXCY
020625,000335: 26,2330 00745 COSCDUY
020626,000336: 26,2331 45425 DSU STADR # PULL UP FROM 6 PD
020627,000337: 26,2332 63756 STODL COSTH # COSTH = CXCY - SXSZSY
020628,000338: 26,2333 00737 SINCDUY
020629,000339: 26,2334 72405 DMP SL1
020630,000340: 26,2335 00751 COSCDUX # CXSY
020631,000341: 26,2336 45415 DAD STADR # PULL UP FROM 4 PD
020632,000342: 26,2337 43754 STCALL SINTH # SINTH = CXSY + SXSZCY
020633,000343: 26,2340 26510 ARCTAN # RETURNS WITH D(MPAC) = PITCH
020634,000344: 26,2341 55525 PDDL VDEF # PITCH INTO 2 PD, ROLL INTO MPAC FROM 2 PD
020635,000345: 26,2342 77634 RTB # VDEF MAKES V(MPAC) = ROLL, PITCH, YAW
020636,000346: 26,2343 21620 V1STO2S
020637,000347: 26,2344 02345 STORE FDAIX # MODE IS TP
020638,000348: 26,2345 77776 EXIT
020639,000349:
020640,000350: 26,2346 31342 ENDBALL CA BALLEXIT
020641,000351:
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Page 479 |
020643,000353: 26,2347 04640 TC BANKJUMP
020644,000354:
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Page 480 |
020646,000356: # PROGRAM DESCRIPTION - VECPOINT
020647,000357:
020648,000358: # THIS INTERPRETIVE SUBROUTINE MAY BE USED TO POINT A SPACECRAFT AXIS IN A DESIRED DIRECTION. THE AXIS
020649,000359: # TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN SUCCESSIVE LOCATIONS OF ERASABLE MEMORY
020650,000360: # BEGINNING WITH THE LOCATION CALLED SCAXIS. THE COMPONENTS OF THIS VECTOR ARE GIVEN IN SPACECRAFT COORDINATES.
020651,000361: # THE DIRECTION IN WHICH THIS AXIS IS TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN
020652,000362: # SUCCESSIVE LOCATIONS OF ERASABLE MEMORY BEGINNING WITH THE ADDRESS CALLED POINTVSM. THE COMPONENTS OF THIS
020653,000363: # VECTOR ARE GIVEN IN STABLE MEMBER COORDINATES. WITH THIS INFORMATION VECPOINT COMPUTES A SET OF THREE GIMBAL
020654,000364: # ANGLES (2S COMPLEMENT) CORESPONDING TO THE CROSS-PRODUCT ROTATION BETWEEN SCAXIS AND POINTVSM AND STORES THEM
020655,000365: # IN T(MPAC) BEFORE RETURNING TO THE CALLER.
020656,000366:
020657,000367: # THIS ROTATION, HOWEVER, MAY BRING THE S/C INTO GIMBAL LOCK. WHEN POINTING A VECTOR IN THE Y-Z PLANE,
020658,000368: # THE TRANSPONDER AXIS, OR THE AOT FOR THE LEM, THE PROGRAM WILL CORRECT THIS PROBLEM BY ROTATING THE CROSS-
020659,000369: # PRODUCT ATTITUDE ABOUT POINTVSM BY A FIXED AMOUNT SUFFICIENT TO ROTATE THE DESIRED S/C ATTITUDE OUT OF GIMBAL
020660,000370: # LOCK. IF THE AXIS TO BE POINTED IS MORE THAN 40.6 DEGREES BUT LESS THAN 60.5 DEG FROM THE +X (OR -X) AXIS,
020661,000371: # THE ADDITIONAL ROTATION TO AVOID GIMAL LOCK IS 35 DEGREES. IF THE AXIS IS MORE THAN 60.5 DEGEES FROM +X (OR -X)
020662,000372: # THE ADDITIONAL ROTATION IS 35 DEGREES. THE GIMBAL ANGLES CORRESPONDING TO THIS ATTITUDE ARE THEN COMPUTED AND
020663,000373: # STORED AS 2S COMPLIMENT ANGLES IN T(MPAC) BEFORE RETURNING TO THE CALLER.
020664,000374:
020665,000375: # WHEN POINTING THE X-AXIS, OR THE THRUST VECTOR, OR ANY VECTOR WITHIN 40.6 DEG OF THE X-AXIS, VECPOINT
020666,000376: # CANNOT CORRECT FOR A CROSS-PRODUCT ROTATION INTO GIMBAL LOCK. IN THIS CASE A PLATFORM REALIGNMENT WOULD BE
020667,000377: # REQUIRED TO POINT THE VECTOR IN THE DESIRED DIRECTION. AT PRESENT NO INDICATION IS GIVEN FOR THIS SITUATION
020668,000378: # EXCEPT THAT THE FINAL MIDDLE GIMBAL ANGLE IN MPAC +2 IS GREATER THAN 59 DEGREES.
020669,000379:
020670,000380: # CALLING SEQUENCE -
020671,000381:
020672,000382: # 1) LOAD SCAXIS, POINTVSM
020673,000383: # 2) CALL
020674,000384: # VECPOINT
020675,000385:
020676,000386: # RETURNS WITH
020677,000387:
020678,000388: # 1) DESIRED OUTER GIMBAL ANGLE IN MPAC
020679,000389: # 2) DESIRED INNER GIMBAL ANGLE IN MPAC +1
020680,000390: # 3) DESIRED MIDDLE GIMBAL ANGLE IN MPAC +2
020681,000391:
020682,000392: # ERASABLES USED -
020683,000393:
020684,000394: # 1) SCAXIS 6
020685,000395: # 2) POINTVSM 6
020686,000396: # 3) MIS 18
020687,000397: # 4) DEL 18
020688,000398: # 5) COF 6
020689,000399: # 6) VECQTEMP 1
020690,000400: # 7) ALL OF VAC AREA 43
020691,000401:
020692,000402: # TOTAL 99
020693,000403:
020694,000404: 27,2000 SETLOC VECPT
020695,000405: 27,2000 BANK
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Page 481 |
020697,000407: 27,2032 COUNT* $$/VECPT
020698,000408:
020699,000409: 27,2032 E6,1676 EBANK= BCDU
020700,000410:
020701,000411: 27,2032 40020 VECPNT1 STQ BOV # THIS ENTRY USES DESIRED CDUS
020702,000412: 27,2033 03325 VECQTEMP # NOT PRESENT - ENTER WITH CDUD'S IN MPAC
020703,000413: 27,2034 56035 VECPNT2
020704,000414: 27,2035 52164 VECPNT2 AXC,2 GOTO
020705,000415: 27,2036 03246 MIS
020706,000416: 27,2037 56046 STORANG
020707,000417: 27,2040 40020 VECPOINT STQ BOV # SAVE RETURN ADDRESS
020708,000418: 27,2041 03325 VECQTEMP
020709,000419: 27,2042 56043 VECLEAR # AND CLEAR OVFIND
020710,000420: 27,2043 47164 VECLEAR AXC,2 RTB
020711,000421: 27,2044 03246 MIS # READ THE PRESENT CDU ANGLES AND
020712,000422: 27,2045 44403 READCDUK # STORE THEM IN PD25, 26, 27
020713,000423: 27,2046 34032 STORANG STCALL 25D
020714,000424: 27,2047 44410 CDUTODCM # S/C AXES TO STABLE MEMBER AXES (MIS)
020715,000425: 27,2050 61375 VLOAD VXM
020716,000426: 27,2051 03773 POINTVSM # RESOLVE THE POINTING DIRECTION VF INTO
020717,000427: 27,2052 03247 MIS # INITIAL S/C AXES (VF = POINTVSM)
020718,000428: 27,2053 77656 UNIT
020719,000429: 27,2054 00035 STORE 28D
020720,000430: # PD 28 29 30 31 32 33
020721,000431: 27,2055 53435 VXV UNIT # TAKE THE CROSS PRODUCT VF X VI
020722,000432: 27,2056 03765 SCAXIS # WHERE VI = SCAXIS
020723,000433: 27,2057 57400 BOV VCOMP
020724,000434: 27,2060 56170 PICKAXIS
020725,000435: 27,2061 17271 STODL COF # CHECK MAGNITUDE
020726,000436: 27,2062 00045 36D # OF CROSS PRODUCT
020727,000437: 27,2063 50025 DSU BMN # VECTOR, IF LESS
020728,000438: 27,2064 14411 DPB-14 # THAN B-14 ASSUME
020729,000439: 27,2065 56170 PICKAXIS # UNIT OPERATION
020730,000440: 27,2066 50375 VLOAD DOT # INVALID.
020731,000441: 27,2067 03765 SCAXIS
020732,000442: 27,2070 00035 28D
020733,000443: 27,2071 65552 SL1 ARCCOS
020734,000444: 27,2072 77624 COMPMATX CALL # NOW COMPUTE THE TRANSFORMATION FROM
020735,000445: 27,2073 44527 DELCOMP # FINAL S/C AXES TO INITIAL S/C AXES MFI
020736,000446: 27,2074 75160 AXC,1 AXC,2
020737,000447: 27,2075 03246 MIS # COMPUTE THE TRANSFORMATION FROM FINAL
020738,000448: 27,2076 02230 KEL # S/C AXES TO STABLE MEMBER AXES
020739,000449: 27,2077 77624 CALL # MFS = MIS MFI
020740,000450: 27,2100 44312 MXM3 # (IN PD LIST)
020741,000451:
020742,000452: 27,2101 51545 DLOAD ABS
020743,000453: 27,2102 00007 6 # MFS6 = SIN(CPSI) $2
020744,000454: 27,2103 50025 DSU BMN
020745,000455: 27,2104 14376 SINGIMLC # = SIN(59 DEGS) $2
020746,000456: 27,2105 56160 FINDGIMB # /CPSI/ LESS THAN 59 DEGS
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Page 482 |
020748,000458: # I.E. DESIRED ATTITUDE NOT IN GIMBAL LOCK
020749,000459:
020750,000460: 27,2106 51545 DLOAD ABS # CHECK TO SEE IF WE ARE POINTING
020751,000461: 27,2107 03765 SCAXIS # THE THRUST AXIS
020752,000462: 27,2110 51025 DSU BPL
020753,000463: 27,2111 14400 SINVEC1 # SIN 49.4 DEGS $2
020754,000464: 27,2112 56160 FINDGIMB # IF SO, WE ARE TRYING TO POINT IT INTO
020755,000465: 27,2113 77775 VLOAD # GIMBAL LOCK, ABORT COULD GO HERE
020756,000466: 27,2114 77626 STADR
020757,000467: 27,2115 50514 STOVL MIS +12D
020758,000468: 27,2116 77626 STADR # STORE MFS (IN PD LIST) IN MIS
020759,000469: 27,2117 50522 STOVL MIS +6
020760,000470: 27,2120 77626 STADR
020761,000471: 27,2121 50530 STOVL MIS
020762,000472: 27,2122 03255 MIS +6 # INNER GIMBAL AXIS IN FINAL S/C AXES
020763,000473: 27,2123 57444 BPL VCOMP # LOCATE THE IG AXIS DIRECTION CLOSEST TO
020764,000474: 27,2124 56125 IGSAMEX # FINAL X S/C AXIS
020765,000475:
020766,000476: 27,2125 50035 IGSAMEX VXV BMN # FIND THE SHORTEST WAY OF ROTATING THE
020767,000477: 27,2126 03765 SCAXIS # S/C OUT OF GIMBAL LOCK BY A ROTATION
020768,000478: 27,2127 56134 U=SCAXIS # ABOUT +- SCAXIS, I.E. IF (IG (SGN MFS3)
020769,000479: # X SCAXIS . XF) LESS THAN 0, U = SCAXIS
020770,000480: # OTHERWISE U = -SCAXIS
020771,000481:
020772,000482: 27,2130 57575 VLOAD VCOMP
020773,000483: 27,2131 03765 SCAXIS
020774,000484: 27,2132 37271 STCALL COF # ROTATE ABOUT -SCAXIS
020775,000485: 27,2133 56137 CHEKAXIS
020776,000486: 27,2134 77775 U=SCAXIS VLOAD
020777,000487: 27,2135 03765 SCAXIS
020778,000488: 27,2136 03271 STORE COF # ROTATE ABOUT + SCAXIS
020779,000489: 27,2137 51545 CHEKAXIS DLOAD ABS
020780,000490: 27,2140 03765 SCAXIS # SEE IF WE ARE POINTING THE AOT
020781,000491: 27,2141 51025 DSU BPL
020782,000492: 27,2142 14402 SINVEC2 # SIN 29.5 DEGS $2
020783,000493: 27,2143 56147 PICKANG1 # IF SO, ROTATE 50 DEGS ABOUT +- SCAXIS
020784,000494: 27,2144 52145 DLOAD GOTO # IF NOT, MUST BE POINTING THE TRANSPONDER
020785,000495: 27,2145 14406 VECANG2 # OR SOME VECTOR IN THE Y, OR Z PLANE
020786,000496: 27,2146 56151 COMPMFSN # IN THIS CASE ROTATE 35 DEGS TO GET OUT
020787,000497: # OF GIMBAL LOCK (VECANG2 $360)
020788,000498: 27,2147 77745 PICKANG1 DLOAD
020789,000499: 27,2150 14404 VECANG1 # = 50 DEGS $360
020790,000500: 27,2151 77624 COMPMFSN CALL
020791,000501: 27,2152 44527 DELCOMP # COMPUTE THE ROTATION ABOUT SCAXIS TO
020792,000502: 27,2153 75160 AXC,1 AXC,2 # BRING MFS OUT OF GIMBAL LOCK
020793,000503: 27,2154 03246 MIS
020794,000504: 27,2155 02230 KEL
020795,000505: 27,2156 77624 CALL # COMPUTE THE NEW TRANSFORMATION FROM
020796,000506: 27,2157 44312 MXM3 # DESIRED S/C AXES TO STABLE MEMBER AXES
020797,000507: # WHICH WILL ALIGN VI WITH VF AND AVOID
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Page 483 |
020799,000509: # GIMBAL LOCK
020800,000510: 27,2160 45160 FINDGIMB AXC,1 CALL
020801,000511: 27,2161 00000 0 # EXTRACT THE COMMANDED CDU ANGLES FROM
020802,000512: 27,2162 44654 DCMTOCDU # THIS MATRIX
020803,000513: 27,2163 40234 RTB SETPD
020804,000514: 27,2164 21620 V1STO2S # CONVERT TO 2:S COMPLEMENT
020805,000515: 27,2165 00001 0
020806,000516: 27,2166 77650 GOTO
020807,000517: 27,2167 03325 VECQTEMP # RETURN TO CALLER
020808,000518:
020809,000519: 27,2170 50375 PICKAXIS VLOAD DOT # IF VF X VI = 0, FIND VF . VI
020810,000520: 27,2171 00035 28D
020811,000521: 27,2172 03765 SCAXIS
020812,000522: 27,2173 72240 BMN TLOAD
020813,000523: 27,2174 54350 ROT180
020814,000524: 27,2175 00032 25D
020815,000525: 27,2176 77650 GOTO # IF VF = VI, CDU DESIRED = PRESENT CDU
020816,000526: 27,2177 03325 VECQTEMP # PRESENT CDU ANGLES
020817,000527:
020818,000528: 35,2000 BANK 35
020819,000529: 26,2000 SETLOC MANUVER1
020820,000530: 26,2000 BANK
020821,000531: 26,2350 47375 ROT180 VLOAD VXV # IF VF, VI ANTIPARALLEL, 108 DEG ROTATION
020822,000532: 26,2351 03255 MIS +6 # IS REQUIRED. Y STABLE MEMBER AXIS IN
020823,000533: 26,2352 06520 HIDPHALF # INITIAL S/C AXES.
020824,000534: 26,2353 47256 UNIT VXV # FIND Y(SM) X X(I)
020825,000535: 26,2354 03765 SCAXIS # FIND UNIT(VI X UNIT(Y(SM) X X(I)))
020826,000536: 26,2355 40056 UNIT BOV # I.E. PICK A VECTOR IN THE PLANE OF X(I),
020827,000537: 26,2356 54372 PICKX # Y(SM) PERPENDICULAR TO VI
020828,000538: 26,2357 17271 STODL COF
020829,000539: 26,2360 00045 36D # CHECK MAGNITUDE
020830,000540: 26,2361 50025 DSU BMN # OF THIS VECTOR.
020831,000541: 26,2362 14411 DPB-14 # IF LESS THAN B-14,
020832,000542: 26,2363 54372 PICKX # PICK X-AXIS.
020833,000543: 26,2364 77775 VLOAD
020834,000544: 26,2365 03271 COF
020835,000545: 26,2366 17271 XROT STODL COF
020836,000546: 26,2367 06520 HIDPHALF
020837,000547: 26,2370 77650 GOTO
020838,000548: 26,2371 56072 COMPMATX
020839,000549: 26,2372 52175 PICKX VLOAD GOTO # PICK THE XAXIS IN THIS CASE
020840,000550: 26,2373 06520 HIDPHALF
020841,000551: 26,2374 54366 XROT
020842,000552: 26,2375 15555 35172 SINGIMLC 2DEC .4285836003 # = SIN(59) $2
020843,000553:
020844,000554: 26,2377 14113 36326 SINVEC1 2DEC .3796356537 # = SIN(49.4) $2
020845,000555:
020846,000556: 26,2401 07701 35703 SINVEC2 2DEC .2462117800 # = SIN(29.5) $2
020847,000557:
020848,000558: 26,2403 04343 21616 VECANG1 2DEC .1388888889 # = 50 DEGREES $360
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Page 484 |
020850,000560: 26,2405 03070 34344 VECANG2 2DEC .09722222222 # = 35 DEGREES $360
020851,000561:
020852,000562: 26,2407 00000 1BITDP OCT 0 # KEEP THIS BEFORE DPB(-14) *********
020853,000563: 26,2410 00001 DPB-14 OCT 00001
020854,000564: 26,2411 00000 OCT 00000
020855,000565:
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Page 485 |
020857,000567: # ROUTINE FOR INITIATING AUTOMATIC MANEUVER VIA KEYBOARD (V49)
020858,000568:
020859,000569: 34,2000 BANK 34
020860,000570: 23,2000 SETLOC R62
020861,000571: 23,2000 BANK
020862,000572: 23,2103 E6,1676 EBANK= BCDU
020863,000573:
020864,000574: 23,2103 COUNT* $$/R62
020865,000575:
020866,000576: 23,2103 23,2103 R62DISP EQUALS R62FLASH
020867,000577:
020868,000578: 23,2103 35010 R62FLASH CAF V06N22 # FLASH V06N22 AND
020869,000579: 23,2104 04616 TC BANKCALL # ICDU ANGLES
020870,000580: 23,2105 20476 CADR GOFLASH
020871,000581: 23,2106 15472 TCF ENDEXT # TERMINATE
020872,000582: 23,2107 12111 TCF GOMOVE # PROCEED
020873,000583: 23,2110 12103 TCF R62FLASH # ENTER
020874,000584:
020875,000585: # ASTRONAUT MAY LOAD NEW ICDUS AT THIS
020876,000586: # POINT
020877,000587: 23,2111 05504 GOMOVE TC UPFLAG # SET FOR 3-AXIS MANEUVER
020878,000588: 23,2112 00124 ADRES 3AXISFLG
020879,000589:
020880,000590: 23,2113 04616 TC BANKCALL
020881,000591: 23,2114 54123 CADR R60LEM
020882,000592: 23,2115 15472 TCF ENDEXT # END R62
020883,000593:
End of include-file R60,R62.agc. Parent file is MAIN.agc