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. |
020177,000002: ## Copyright: Public domain.
020178,000003: ## Filename: R60_R62.agc
020179,000004: ## Purpose: Part of the source code for Luminary 1A build 099.
020180,000005: ## It is part of the source code for the Lunar Module's (LM)
020181,000006: ## Apollo Guidance Computer (AGC), for Apollo 11.
020182,000007: ## Assembler: yaYUL
020183,000008: ## Contact: Ron Burkey <info@sandroid.org>.
020184,000009: ## Website: www.ibiblio.org/apollo.
020185,000010: ## Pages: 472-485
020186,000011: ## Mod history: 2009-05-17 RSB Adapted from the corresponding
020187,000012: ## Luminary131 file, using page
020188,000013: ## images from Luminary 1A.
020189,000014: ##
020190,000015: ## This source code has been transcribed or otherwise adapted from
020191,000016: ## digitized images of a hardcopy from the MIT Museum. The digitization
020192,000017: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
020193,000018: ## the Museum. Many thanks to both. The images (with suitable reduction
020194,000019: ## in storage size and consequent reduction in image quality as well) are
020195,000020: ## available online at www.ibiblio.org/apollo. If for some reason you
020196,000021: ## find that the images are illegible, contact me at info@sandroid.org
020197,000022: ## about getting access to the (much) higher-quality images which Paul
020198,000023: ## actually created.
020199,000024: ##
020200,000025: ## Notations on the hardcopy document read, in part:
020201,000026: ##
020202,000027: ## Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
020203,000028: ## 16:27 JULY 14, 1969
020204,000029:
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Page 472 |
020206,000031: # MOD NO: 0 DATE: 1 MAY 1968
020207,000032: # MOD BY: DIGITAL DEVEL GROUP LOG SECTION R60,R62
020208,000033:
020209,000034: # FUNCTIONAL DESCRIPTION:
020210,000035:
020211,000036: # CALLED AS A GENERAL SUBROUTINE TO MANEUVER THE LM TO A SPECIFIED
020212,000037: # ATTITUDE.
020213,000038:
020214,000039: # 1. IF THE 3-AXIS FLAG IS NOT SET THE FINAL CDU ANGLES ARE
020215,000040: # CALCULATED (VECPOINT).
020216,000041:
020217,000042: # 2. THE FDAI BALL ANGLES (NOUN 18) ARE CALCULATED (BALLANGS).
020218,000043:
020219,000044: # 3. REQUEST FLASHING DISPLAY V50 N18 PLEASE PERFORM AUTO MANEUVER.
020220,000045:
020221,000046: # 4. IF PRIORITY DISPLAY FLAG IS SET DO A PHASECHANGE. THEN AWAIT
020222,000047: # ASTRONAUT RESPONSE.
020223,000048:
020224,000049: # 5. DISPLAY RESPONSE RETURNS.
020225,000050:
020226,000051: # A. ENTER -- RESET 3-AXIS FLAG AND RETURN TO CLIENT.
020227,000052:
020228,000053: # B. TERMINATE -- IF IN P00 GO TO STEP 5A. OTHERWISE CHECK IF R61 IS
020229,000054: # THE CALLING PROGRAM. IF IN R61 AN EXIT IS MADE TO GOTOV56. IF
020230,000055: # NOT IN R61 AN EXIT IS DONE VIA GOTOP00H.
020231,000056:
020232,000057: # C. PROCEED -- CONTINUE WITH PROGRAM AT STEP 6.
020233,000058:
020234,000059: # 6. IF THE 3-AXISFLAG IS NOT SET, THE FINAL CDU ANGLES ARE CALCULATED
020235,000060: # (VECPOINT).
020236,000061:
020237,000062: # 7. THE FDAI BALL ANGLES (NOUN 18) ARE CALCULATED (BALLANGS).
020238,000063:
020239,000064: # 8. IF THE G+N SWITCH IS NOT SET GO BACK TO STEP 3.
020240,000065: #
020241,000066: # 9. IF THE AUTO SWITCH IS NOT SET GO BACK TO STEP 3.
020242,000067:
020243,000068: # 10. NON-FLASHING DISPLAY V06N18 (FDAI ANGLES).
020244,000069:
020245,000070: # 11. DO A PHASE-CHANGE.
020246,000071:
020247,000072: # 12. DO A MANEUVER CALCULATION AND ICDU DRIVE ROUTINE TO ACHIEVE FINAL
020248,000073: # GIMBAL ANGLES (GOMANUR).
020249,000074:
020250,000075: # 13. AT END OF MANEUVER TO TO STEP 3.
020251,000076:
020252,000077: # IF SATISFACTORY MANEUVER STEP 5A EXITS R60.
020253,000078: # FOR FURTHER ADJUSTMENT OF THE VEHICLE ATTITUDE ABOUT THE
020254,000079: # DESIRED VECTOR, THE ROUTINE MAY BE PERFORMED AGAIN STARTING AT
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Page 473 |
020256,000081: # STEP 5C.
020257,000082:
020258,000083: # CALLING SEQUENCE: TC BANKCALL
020259,000084: # CADR R60LEM
020260,000085:
020261,000086: # ERASABLE INITIALIZATION REQUIRED: SCAXIS, POINTVSM (FOR VECPOINT)
020262,000087: # 3AXISFLG.
020263,000088:
020264,000089: # SUBROUTINES CALLED: VECPOINT, BALLANGS, GOPERF24, LINUS, GODSPER,
020265,000090: # GOMANUR, DOWNFLAG, PHASCHNG, UPFLAG
020266,000091:
020267,000092: # NORMAL EXIT MODES: CAE TEMPR60 (CALLER'S RETURN ADDRESS)
020268,000093: # TC BANKJUMP
020269,000094:
020270,000095: # ALARMS: NONE
020271,000096:
020272,000097: # OUTPUT: NONE
020273,000098:
020274,000099: # DEBRIS: CPHI, CTHETA, CPSI, 3AXISFLG, TBASE2
020275,000100:
020276,000101: 34,2000 BANK 34
020277,000102: 26,2000 SETLOC MANUVER
020278,000103: 26,2000 BANK
020279,000104:
020280,000105: 26,2123 1164 EBANK= TEMPR60
020281,000106:
020282,000107: 26,2123 COUNT* $$/R06
020283,000108: 26,2123 04645 R60LEM TC MAKECADR
020284,000109: 26,2124 55164 TS TEMPR60
020285,000110:
020286,000111: 26,2125 34746 REDOMANN CAF 3AXISBIT
020287,000112: 26,2126 70101 MASK FLAGWRD5 # IS 3-AXIS FLAG SET
020288,000113: 26,2127 10000 CCS A
020289,000114: 26,2130 12136 TCF TOBALL # YES
020290,000115: 26,2131 06037 TC INTPRET
020291,000116: 26,2132 77624 CALL
020292,000117: 26,2133 56040 VECPOINT # TO COMPUTE FINAL ANGLES
020293,000118: 26,2134 00322 STORE CPHI # STORE FINAL ANGLES -- CPHI, CTHETA, CPSI
020294,000119: 26,2135 77776 EXIT
020295,000120:
020296,000121: 26,2136 04616 TOBALL TC BANKCALL
020297,000122: 26,2137 54266 CADR BALLANGS # TO CONVERT ANGLES TO FDAI
020298,000123: 26,2140 32254 TOBALLA CAF V06N18
020299,000124: 26,2141 04616 TC BANKCALL
020300,000125: 26,2142 20710 CADR GOPERF2R # DISPLAY PLEASE PERFORM AUTO MANEUVER
020301,000126: 26,2143 02242 TC R61TEST
020302,000127: 26,2144 02150 TC REDOMANC # PROCEED
020303,000128: 26,2145 02175 TC ENDMANU1 # ENTER I.E., FINISHED WITH R60
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020305,000130: 26,2146 02201 TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
020306,000131: 26,2147 05155 TC ENDOFJOB
020307,000132:
020308,000133: 26,2150 34746 REDOMANC CAF 3AXISBIT
020309,000134: 26,2151 70101 MASK FLAGWRD5 # IS 3-AXIS FLAG SET
020310,000135: 26,2152 10000 CCS A
020311,000136: 26,2153 12161 TCF TOBALLC # YES
020312,000137: 26,2154 06037 TC INTPRET
020313,000138: 26,2155 77624 CALL
020314,000139: 26,2156 56040 VECPOINT # TO COMPUTE FINAL ANGLES
020315,000140: 26,2157 00322 STORE CPHI # STORE ANGLES
020316,000141: 26,2160 77776 EXIT
020317,000142:
020318,000143: 26,2161 04616 TOBALLC TC BANKCALL
020319,000144: 26,2162 54266 CADR BALLANGS # TO CONVERT ANGLES TO FDAI
020320,000145: 26,2163 02255 TC G+N,AUTO # CHECK AUTO MODE
020321,000146: 26,2164 10000 CCS A
020322,000147: 26,2165 12140 TCF TOBALLA # NOT AUTO, GO REREQUEST AUTO MANEUVER.
020323,000148:
020324,000149: 26,2166 32254 AUTOMANV CAF V06N18 # STATIC DISPLAY DURING AUTO MANEUVER
020325,000150: 26,2167 04616 TC BANKCALL
020326,000151: 26,2170 20451 CADR GODSPR
020327,000152: 26,2171 02201 TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
020328,000153:
020329,000154: 26,2172 04616 STARTMNV TC BANKCALL # PERFORM MANEUVER VIA KALCMANU
020330,000155: 26,2173 17750 CADR GOMANUR
020331,000156:
020332,000157: 26,2174 12140 ENDMANUV TCF TOBALLA # FINISHED MANEUVER.
020333,000158: 26,2175 05516 ENDMANU1 TC DOWNFLAG # RESET 3-AXIS FLAG
020334,000159: 26,2176 00124 ADRES 3AXISFLG
020335,000160: 26,2177 31164 CAE TEMPR60
020336,000161: 26,2200 04640 TC BANKJUMP
020337,000162:
020338,000163: 26,2201 40100 CHKLINUS CS FLAGWRD4
020339,000164: 26,2202 74740 MASK PDSPFBIT # IS PRIORITY DISPLAY FLAG SET?
020340,000165: 26,2203 10000 CCS A
020341,000166: 26,2204 00002 TC Q # NO -- EXIT
020342,000167: 26,2205 30002 CA Q
020343,000168: 26,2206 54156 TS MPAC +2 # SAVE RETURN
020344,000169: 26,2207 46245 CS THREE # OBTAIN LOCATION FOR RESTART
020345,000170: 26,2210 60133 AD BUF2 # HOLD Q OF LAST DISPLAY
020346,000171: 26,2211 55055 TS TBASE2
020347,000172:
020348,000173: 26,2212 05353 TC PHASCHNG
020349,000174: 26,2213 00132 OCT 00132
020350,000175:
020351,000176: 26,2214 34745 CAF BIT7
020352,000177: 26,2215 05464 TC LINUS # GO SET BITS FOR PRIORITY DISPLAY
020353,000178: 26,2216 00156 TC MPAC +2
020354,000179:
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020356,000181: 26,2217 37714 RELINUS CAF PRIO26 # RESTORE ORIGINAL PRIORITY
020357,000182: 26,2220 05146 TC PRIOCHNG
020358,000183:
020359,000184: 26,2221 34747 CAF TRACKBIT # DON'T CONTINUE R60 UNLESS TRACKFLAG ON.
020360,000185: 26,2222 70075 MASK FLAGWRD1
020361,000186: 26,2223 10000 CCS A
020362,000187: 26,2224 12237 TCF RER60
020363,000188:
020364,000189: 26,2225 34745 CAF RNDVZBIT # IS IT P20?
020365,000190: 26,2226 70074 MASK FLAGWRD0
020366,000191: 26,2227 10000 CCS A
020367,000192: 26,2230 02234 TC +4 # YES
020368,000193: 26,2231 05353 TC PHASCHNG # NO, MUST BE P25, SET 2.11 SPOT
020369,000194: 26,2232 40112 OCT 40112
020370,000195:
020371,000196: 26,2233 05155 TC ENDOFJOB
020372,000197:
020373,000198: 26,2234 05353 TC PHASCHNG # SET 2.7 SPOT FOR P20
020374,000199: 26,2235 40072 OCT 40072
020375,000200:
020376,000201: 26,2236 05155 TC ENDOFJOB
020377,000202:
020378,000203: 26,2237 05504 RER60 TC UPFLAG # SET PRIO DISPLAY FLAG AFTER RESTART
020379,000204: 26,2240 00077 ADRES PDSPFLAG
020380,000205:
020381,000206: 26,2241 01055 TC TBASE2
020382,000207:
020383,000208: 26,2242 31011 R61TEST CA MODREG # IF WE ARE IN P00 IT MUST BE V49 OR V89
020384,000209: 26,2243 00006 EXTEND
020385,000210: 26,2244 12175 BZF ENDMANU1 # THUS WE GO TO ENDEXT VIA USER
020386,000211:
020387,000212: 26,2245 30100 CA FLAGWRD4 # ARE WE IN R61 (P20 OR P25)
020388,000213: 26,2246 74740 MASK PDSPFBIT
020389,000214: 26,2247 00006 EXTEND
020390,000215: 26,2250 16001 BZF GOTOP00H # NO
020391,000216: 26,2251 06022 TC GOTOV56 # YES
020392,000217:
020393,000218: 26,2252 20100 BIT14+7 OCT 20100
020394,000219: 26,2253 00203 OCT203 OCT 203
020395,000220: 26,2254 01422 V06N18 VN 0618
020396,000221:
020397,000222: # SUBROUTINE TO CHECK FOR G+N CONTROL, AUTO STABILIZATION
020398,000223:
020399,000224: # RETURNS WITH C(A) = + IF NOT SET FOR G+N, AUTO
020400,000225: # RETURNS WITH C(A) = +0 IF SWITCHES ARE SET
020401,000226:
020402,000227: 26,2255 00006 G+N,AUTO EXTEND
020403,000228: 26,2256 00030 READ CHAN30
020404,000229: 26,2257 74742 MASK BIT10
020405,000230: 26,2260 10000 CCS A
020406,000231: 26,2261 00002 TC Q # NOT IN G+N C(A) = +
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020408,000233: 26,2262 00006 ISITAUTO EXTEND # CHECK FOR AUTO MODE
020409,000234: 26,2263 00031 READ CHAN31
020410,000235: 26,2264 74736 MASK BIT14
020411,000236: 26,2265 00002 TC Q # (+) = NOT IN AUTO, (+0) = AOK
020412,000237:
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Page 477 |
020414,000239: # PROGRAM DESCRIPTION BALLANGS
020415,000240: # MOD NO. LOG SECTION R60,R62
020416,000241:
020417,000242: # WRITTEN BY RAMA M. AIYAWAR
020418,000243:
020419,000244: # FUNCTIONAL DESCRIPTION
020420,000245:
020421,000246: # COMPUTES LM FDAI BALL DISPLAY ANGLES
020422,000247:
020423,000248: # CALLING SEQUENCE
020424,000249:
020425,000250: # TC BALLANGS
020426,000251:
020427,000252: # NORMAL EXIT MODE
020428,000253:
020429,000254: # TC BALLEXIT # (SAVED Q)
020430,000255:
020431,000256: # ALARM OR EXIT MODE: NIL
020432,000257:
020433,000258: # SUBROUTINES CALLED
020434,000259:
020435,000260: # CD*TR*G
020436,000261: # ARCTAN
020437,000262:
020438,000263: # INPUT
020439,000264:
020440,000265: # CPHI,CTHETA,CPSI ARE THE ANGLES CORRESPONDING TO AOG, AIG, AMG. THEY ARE
020441,000266: # SP,2'S COMPLEMENT SCALED TO HALF REVOLUTION.
020442,000267:
020443,000268: # OUTPUT
020444,000269:
020445,000270: # FDAIX, FDAIY, FDAIZ ARE THE REQUIRED BALL ANGLES SCALED TO HALF REVOLUTION
020446,000271: # SP,2'S COMPEMENT.
020447,000272:
020448,000273: # THESE ANGLES WILL BE DISPLAYED AS DEGREES AND HUNDREDTHS, IN THE ORDER ROLL, PITCH, YAW, USING NOUNS 18 & 19.
020449,000274:
020450,000275: # ERASABLE INITIALIZATION REQUIRED
020451,000276:
020452,000277: # CPHI, CTHETA, CPSI EACH AN SP REGISTER
020453,000278:
020454,000279: # DEBRIS
020455,000280:
020456,000281: # A,L,Q,MPAC,SINCDU,COSCDU,PUSHLIST,BALLEXIT
020457,000282:
020458,000283: # NOMENCLATURE: CPHI, CTHETA, & CPSI REPRESENT THE OUTER, INNER, AND MIDDLE GIMBAL ANGLES, RESPECTIVELY; OR
020459,000284: # EQUIVALENTLY, CDUX, CDUY, AND CDUZ.
020460,000285:
020461,000286: # NOTE: ARCTAN CHECKS FOR OVERFLOW AND SHOULD BE ABLE TO HANDLE ANY SINGULARITIES.
020462,000287:
020463,000288: 26,2000 SETLOC BAWLANGS
020464,000289: 26,2000 BANK
020465,000290:
020466,000291: 26,2266 COUNT* $$/BALL
020467,000292: 26,2266 04645 BALLANGS TC MAKECADR
020468,000293: 26,2267 55342 TS BALLEXIT
020469,000294: 26,2270 30321 CA CPHI
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020471,000296: 26,2271 54772 TS CDUSPOT +4
020472,000297: 26,2272 30322 CA CTHETA
020473,000298: 26,2273 54766 TS CDUSPOT
020474,000299: 26,2274 30323 CA CPSI
020475,000300: 26,2275 54770 TS CDUSPOT +2
020476,000301:
020477,000302: 26,2276 06037 TC INTPRET
020478,000303: 26,2277 45001 SETPD CALL
020479,000304: 26,2300 00001 0D
020480,000305: 26,2301 47543 CD*TR*G
020481,000306:
020482,000307: 26,2302 41345 DLOAD DMP
020483,000308: 26,2303 00743 SINCDUX # SIN (OGA)
020484,000309: 26,2304 00747 COSCDUZ # COS (MGA)
020485,000310:
020486,000311: 26,2305 57552 SL1 DCOMP # SCALE
020487,000312: 26,2306 65336 ARCSIN PDDL # YAW = ARCSIN(-SXCZ) INTO 0 PD
020488,000313: 26,2307 00741 SINCDUZ
020489,000314: 26,2310 14023 STODL SINTH # (SINTH = 18D IN PD)
020490,000315: 26,2311 00747 COSCDUZ
020491,000316: 26,2312 72405 DMP SL1 # RESCALE
020492,000317: 26,2313 00751 COSCDUX
020493,000318: 26,2314 34021 STCALL COSTH # (COSTH = 16D IN PD)
020494,000319: 26,2315 26510 ARCTAN
020495,000320: 26,2316 41325 PDDL DMP # ROLL = ARCTAN(SZ/CZCX) INTO 2 PD
020496,000321: 26,2317 00741 SINCDUZ
020497,000322: 26,2320 00743 SINCDUX
020498,000323: 26,2321 41512 SL2 PUSH # SXSZ INTO 4 PD
020499,000324: 26,2322 65205 DMP PDDL # SXSZCY INTO 4 PD
020500,000325: 26,2323 00745 COSCDUY
020501,000326: 26,2324 65205 DMP PDDL # SXSZSY INTO 6 PD
020502,000327: 26,2325 00737 SINCDUY
020503,000328: 26,2326 00751 COSCDUX
020504,000329: 26,2327 72405 DMP SL1 # CXCY
020505,000330: 26,2330 00745 COSCDUY
020506,000331: 26,2331 45425 DSU STADR # PULL UP FORM 6 PD
020507,000332: 26,2332 63756 STODL COSTH # COSTH = CXCY - SXSZSY
020508,000333: 26,2333 00737 SINCDUY
020509,000334: 26,2334 72405 DMP SL1
020510,000335: 26,2335 00751 COSCDUX # CXSY
020511,000336: 26,2336 45415 DAD STADR # PULL UP FORM 4 PD
020512,000337: 26,2337 43754 STCALL SINTH # SINTH = CXSY + SXSZCY
020513,000338: 26,2340 26510 ARCTAN # RETURNS WITH D(MPAC) = PITCH
020514,000339: 26,2341 55525 PDDL VDEF # PITCH INTO 2 PD, ROLL INTO MPAC FROM 2 PD
020515,000340: 26,2342 77634 RTB # VDEF MAKES V(MPAC) = ROLL, PITCH, YAW
020516,000341: 26,2343 21620 V1STO2S
020517,000342: 26,2344 02345 STORE FDAIX # MODE IS TP
020518,000343: 26,2345 77776 EXIT
020519,000344:
020520,000345: 26,2346 31342 ENDBALL CA BALLEXIT
020521,000346:
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020523,000348: 26,2347 04640 TC BANKJUMP
020524,000349:
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020526,000351: # PROGRAM DESCRIPTION -- VECPOINT
020527,000352:
020528,000353: # THIS INTERPRETIVE SUBROUTINE MAY BE USED TO POINT A SPACECRAFT AXIS IN A DESIRED DIRECTION. THE AXIS
020529,000354: # TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN SUCCESSIVE LOCATIONS OF ERASABLE MEMORY
020530,000355: # BEGINNING WITH THE LOCATION CALLED SCAXIS. THE COMPONENTS OF THIS VECTOR ARE GIVEN IN SPACECRAFT COORDINATES.
020531,000356: # THE DIRECTION IN WHICH THIS AXIS IS TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN
020532,000357: # SUCCESSIVE LOCATIONS OF ERASABLE MEMORY BEGINNING WITH THE ADDRESS CALLED POINTVSM. THE COMPONENTS OF THIS
020533,000358: # VECTOR ARE GIVEN IN STABLE MEMBER COORDINATES. WITH THIS INFORMTION VECPOINT COMPUTES A SET OF THREE GIMBAL
020534,000359: # ANGLES (2'S COMPLEMENT) CORRESPONDING TO THE CROSS-PRODUCT ROTATION BETWEEN SCAXIS AND POINTVSM AND STORES THEM
020535,000360: # IN T(MPAC) BEFORE RETURNING TO THE CALLER.
020536,000361:
020537,000362: # THIS ROTATION, HOWEVER, MAY BRING THE S/C INTO GIMBAL LOCK. WHEN POINTING A VECTOR IN THE Y-Z PLANE,
020538,000363: # THE TRANSPONDER AXIS, OR THE AOT FOR THE LEM, THE PROGRAM WILL CORRECT THIS PROBLEM BY ROTATING THE CROSS-
020539,000364: # PRODUCT ATTITUDE ABOUT POINTVSM BY A FIXED AMOUNT SUFFICIENT TO ROTATE THE DESIRED S/C ATTITUDE OUT OF GIMBAL
020540,000365: # 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,
020541,000366: # THE ADDITIONAL ROTATION TO AVOID GIMBAL LOCK IS 35 DEGREES. IF THE AXIS IS MORE THAN 60.5 DEGREES FROM +X (OR -X)
020542,000367: # THE ADDITIONAL ROTATION IS 35 DEGREES. THE GIMBAL ANGLES CORRESPONDING TO THIS ATTITUDE ARE THEN COMPUTED AND
020543,000368: # STORED AS 2'S COMPLEMENT ANGLES IN T(MPAC) BEFORE RETURNING TO THE CALLER.
020544,000369:
020545,000370: # WHEN POINTING THE X-AXIS, OR THE THRUST VECTOR, OR ANY VECTOR WITHIN 40.6 DEG OF THE X-AXIS, VECPOINT
020546,000371: # CANNOT CORRECT FOR A CROSS-PRODUCT ROTATION INTO GIMBAL LOCK. IN THIS CASE A PLATFORM REALIGNMENT WOULD BE
020547,000372: # REQUIRED TO POINT THE VECTOR IN THE DESIRED DIRECTION. AT PRESENT NO INDICATION IS GIVEN FOR THIS SITUATION
020548,000373: # EXCEPT THAT THE FINAL MIDDLE GIMBAL ANGLE IN MPAC +2 IS GREATER THAN 59 DEGREES.
020549,000374:
020550,000375: # CALLING SEQUENCE
020551,000376:
020552,000377: # 1) LOAD SCAXIS, POINTVSM
020553,000378: # 2) CALL
020554,000379: # VECPOINT
020555,000380:
020556,000381: # RETURNS WITH
020557,000382:
020558,000383: # 1) DESIRED OUTER GIMBAL ANGLE IN MPAC
020559,000384: # 2) DESIRED INNER GIMBAL ANGLE IN MPAC +1
020560,000385: # 3) DESIRED MIDDLE GIMBAL ANGLE IN MPAC +2
020561,000386:
020562,000387: # ERASABLES USED --
020563,000388:
020564,000389: # 1) SCAXIS 6
020565,000390: # 2) POINTVSM 6
020566,000391: # 3) MIS 18
020567,000392: # 4) DEL 18
020568,000393: # 5) COF 6
020569,000394: # 6) VECQTEMP 1
020570,000395: # 7) ALL OF VAC AREA 43
020571,000396:
020572,000397: # TOTAL 99
020573,000398:
020574,000399: 27,2000 SETLOC VECPT
020575,000400: 27,2000 BANK
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020577,000402: 27,2032 COUNT* $$/VECPT
020578,000403:
020579,000404: 27,2032 E6,1676 EBANK= BCDU
020580,000405:
020581,000406: 27,2032 40020 VECPNT1 STQ BOV # THIS ENTRY USES DESIRED CDUS
020582,000407: 27,2033 03325 VECQTEMP # NOT PRESENT -- ENTER WITH CDUD'S IN MPAC
020583,000408: 27,2034 56035 VECPNT2
020584,000409: 27,2035 52164 VECPNT2 AXC,2 GOTO
020585,000410: 27,2036 03246 MIS
020586,000411: 27,2037 56046 STORANG
020587,000412: 27,2040 40020 VECPOINT STQ BOV # SAVE RETURN ADDRESS
020588,000413: 27,2041 03325 VECQTEMP
020589,000414: 27,2042 56043 VECLEAR # AND CLEAR OVFIND
020590,000415: 27,2043 47164 VECLEAR AXC,2 RTB
020591,000416: 27,2044 03246 MIS # READ THE PRESENT CDU ANGLES AND
020592,000417: 27,2045 44403 READCDUK # STORE THEM IN PD25, 26, 27
020593,000418: 27,2046 34032 STORANG STCALL 25D
020594,000419: 27,2047 44410 CDUTODCM # S/C AXES TO STABLE MEMBER AXES (MIS)
020595,000420: 27,2050 61375 VLOAD VXM
020596,000421: 27,2051 03773 POINTVSM # RESOLVE THE POINTING DIRECTION VF INTO
020597,000422: 27,2052 03247 MIS # INITIAL S/C AXES (VF = POINTVSM)
020598,000423: 27,2053 77656 UNIT
020599,000424: 27,2054 00035 STORE 28D
020600,000425: # PD 28 29 30 31 32 33
020601,000426: 27,2055 53435 VXV UNIT # TAKE THE CROSS PRODUCT VF X VI
020602,000427: 27,2056 03765 SCAXIS # WHERE VI = SCAXIS
020603,000428: 27,2057 57400 BOV VCOMP
020604,000429: 27,2060 56170 PICKAXIS
020605,000430: 27,2061 17271 STODL COF # CHECK MAGNITUDE
020606,000431: 27,2062 00045 36D # OF CROSS PRODUCT
020607,000432: 27,2063 50025 DSU BMN # VECTOR, IF LESS
020608,000433: 27,2064 14411 DPB-14 # THAN B-14 ASSUME
020609,000434: 27,2065 56170 PICKAXIS # UNIT OPERATION
020610,000435: 27,2066 50375 VLOAD DOT # INVALID.
020611,000436: 27,2067 03765 SCAXIS
020612,000437: 27,2070 00035 28D
020613,000438: 27,2071 65552 SL1 ARCCOS
020614,000439: 27,2072 77624 COMPMATX CALL # NOW COMPUTE THE TRANSFORMATION FROM
020615,000440: 27,2073 44527 DELCOMP # FINAL S/C AXES TO INITIAL S/C AXES MFI
020616,000441: 27,2074 75160 AXC,1 AXC,2
020617,000442: 27,2075 03246 MIS # COMPUTE THE TRANSFORMATION FROM FINAL
020618,000443: 27,2076 02230 KEL # S/C AXES TO STABLE MEMBER AXES
020619,000444: 27,2077 77624 CALL # MFS = MIS MFI
020620,000445: 27,2100 44312 MXM3 # (IN PD LIST)
020621,000446:
020622,000447: 27,2101 51545 DLOAD ABS
020623,000448: 27,2102 00007 6 # MFS6 = SIN(CPSI) $2
020624,000449: 27,2103 50025 DSU BMN
020625,000450: 27,2104 14376 SINGIMLC # = SIN(59 DEGS) $2
020626,000451: 27,2105 56160 FINDGIMB # /CPSI/ LESS THAN 59 DEGS.
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Page 482 |
020628,000453: # I.E., DESIRED ATTITUDE NOT IN GIMBAL LOCK
020629,000454:
020630,000455: 27,2106 51545 DLOAD ABS # CHECK TO SEE IF WE ARE POINTING
020631,000456: 27,2107 03765 SCAXIS # THE THRUST AXIS
020632,000457: 27,2110 51025 DSU BPL
020633,000458: 27,2111 14400 SINVEC1 # SIN 49.4 DEGS $2
020634,000459: 27,2112 56160 FINDGIMB # IF SO, WE ARE TRYING TO POINT IT INTO
020635,000460: 27,2113 77775 VLOAD # GIMBAL LOCK, ABORT COULD GO HERE
020636,000461: 27,2114 77626 STADR
020637,000462: 27,2115 50514 STOVL MIS +12D
020638,000463: 27,2116 77626 STADR # STORE MFS (IN PD LIST) IN MIS
020639,000464: 27,2117 50522 STOVL MIS +6
020640,000465: 27,2120 77626 STADR
020641,000466: 27,2121 50530 STOVL MIS
020642,000467: 27,2122 03255 MIS +6 # INNER GIMBAL AXIS IN FINAL S/C AXES
020643,000468: 27,2123 57444 BPL VCOMP # LOCATE THE IG AXIS DIRECTION CLOSEST TO
020644,000469: 27,2124 56125 IGSAMEX # FINAL X S/C AXIS
020645,000470:
020646,000471: 27,2125 50035 IGSAMEX VXV BMN # FIND THE SHORTEST WAY OF ROTATING THE
020647,000472: 27,2126 03765 SCAXIS # S/C OUT OF GIMBAL LOCK BY A ROTATION
020648,000473: 27,2127 56134 U=SCAXIS # ABOUT +- SCAXIS, I.E., IF (IG (SGN MFS3)
020649,000474: # X SCAXIS . XF) LESS THAN 0, U = SCAXIS
020650,000475: # OTHERWISE U = -SCAXIS.
020651,000476:
020652,000477: 27,2130 57575 VLOAD VCOMP
020653,000478: 27,2131 03765 SCAXIS
020654,000479: 27,2132 37271 STCALL COF # ROTATE ABOUT -SCAXIS
020655,000480: 27,2133 56137 CHEKAXIS
020656,000481: 27,2134 77775 U=SCAXIS VLOAD
020657,000482: 27,2135 03765 SCAXIS
020658,000483: 27,2136 03271 STORE COF # ROTATE ABOUT + SCAXIS
020659,000484: 27,2137 51545 CHEKAXIS DLOAD ABS
020660,000485: 27,2140 03765 SCAXIS # SEE IF WE ARE POINTING THE AOT
020661,000486: 27,2141 51025 DSU BPL
020662,000487: 27,2142 14402 SINVEC2 # SIN 29.5 DEGS $2
020663,000488: 27,2143 56147 PICKANG1 # IF SO, ROTATE 50 DEGS ABOUT +- SCAXIS
020664,000489: 27,2144 52145 DLOAD GOTO # IF NOT, MUST BE POINTING THE TRANSPONDER
020665,000490: 27,2145 14406 VECANG2 # OR SOME VECTOR IN THE Y, OR Z PLANE
020666,000491: 27,2146 56151 COMPMFSN # IN THIS CASE ROTATE 35 DEGS TO GET OUT
020667,000492: # OF GIMBAL LOCK (VECANG2 $360)
020668,000493: 27,2147 77745 PICKANG1 DLOAD
020669,000494: 27,2150 14404 VECANG1 # = 50 DEGS. $360
020670,000495: 27,2151 77624 COMPMFSN CALL
020671,000496: 27,2152 44527 DELCOMP # COMPUTE THE ROTATION ABOUT SCAXIS TO
020672,000497: 27,2153 75160 AXC,1 AXC,2 # BRING MFS OUT OF GIMBAL LOCK
020673,000498: 27,2154 03246 MIS
020674,000499: 27,2155 02230 KEL
020675,000500: 27,2156 77624 CALL # COMPUTE THE NEW TRANSFORMATION FROM
020676,000501: 27,2157 44312 MXM3 # DESIRED S/C AXES TO STABLE MEMBER AXES
020677,000502: # WHICH WILL ALIGN VI WITH VF AND AVOID
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020679,000504: # GIMBAL LOCK
020680,000505: 27,2160 45160 FINDGIMB AXC,1 CALL
020681,000506: 27,2161 00000 0 # EXTRACT THE COMMANDED CDU ANGLES FROM
020682,000507: 27,2162 44654 DCMTOCDU # THIS MATRIX
020683,000508: 27,2163 40234 RTB SETPD
020684,000509: 27,2164 21620 V1STO2S # CONVERT TO 2'S COMPLEMENT
020685,000510: 27,2165 00001 0
020686,000511: 27,2166 77650 GOTO
020687,000512: 27,2167 03325 VECQTEMP # RETURN TO CALLER
020688,000513:
020689,000514: 27,2170 50375 PICKAXIS VLOAD DOT # IF VF X VI = 0, FIND VF, VI
020690,000515: 27,2171 00035 28D
020691,000516: 27,2172 03765 SCAXIS
020692,000517: 27,2173 72240 BMN TLOAD
020693,000518: 27,2174 54350 ROT180
020694,000519: 27,2175 00032 25D
020695,000520: 27,2176 77650 GOTO # IF VF = VI, CDU DESIRED = PRESENT CDU
020696,000521: 27,2177 03325 VECQTEMP # PRESENT CDU ANGLES
020697,000522:
020698,000523: 35,2000 BANK 35
020699,000524: 26,2000 SETLOC MANUVER1
020700,000525: 26,2000 BANK
020701,000526: 26,2350 47375 ROT180 VLOAD VXV # IF VF, VI ANTIPARALLEL, 180 DEG ROTATION
020702,000527: 26,2351 03255 MIS +6 # IS REQUIRED. Y STABLE MEMBER AXIS IN
020703,000528: 26,2352 06520 HIDPHALF # INITIAL S/C AXES.
020704,000529: 26,2353 47256 UNIT VXV # FIND Y(SM) X X(I)
020705,000530: 26,2354 03765 SCAXIS # FIND UNIT(VI X UNIT(Y(SM) X X(I)))
020706,000531: 26,2355 40056 UNIT BOV # I.E., PICK A VECTOR IN THE PLANE OF X(I),
020707,000532: 26,2356 54372 PICKX # Y(SM) PERPENDICULAR TO VI
020708,000533: 26,2357 17271 STODL COF
020709,000534: 26,2360 00045 36D # CHECK MAGNITUDE
020710,000535: 26,2361 50025 DSU BMN # OF THIS VECTOR.
020711,000536: 26,2362 14411 DPB-14 # IF LESS THAN B-14,
020712,000537: 26,2363 54372 PICKX # PICK X-AXIS.
020713,000538: 26,2364 77775 VLOAD
020714,000539: 26,2365 03271 COF
020715,000540: 26,2366 17271 XROT STODL COF
020716,000541: 26,2367 06520 HIDPHALF
020717,000542: 26,2370 77650 GOTO
020718,000543: 26,2371 56072 COMPMATX
020719,000544: 26,2372 52175 PICKX VLOAD GOTO # PICK THE XAXIS IN THIS CASE
020720,000545: 26,2373 06520 HIDPHALF
020721,000546: 26,2374 54366 XROT
020722,000547: 26,2375 15555 35172 SINGIMLC 2DEC .4285836003 # = SIN(59) $2
020723,000548:
020724,000549: 26,2377 14113 36326 SINVEC1 2DEC .3796356537 # = SIN(49.4) $2
020725,000550:
020726,000551: 26,2401 07701 35703 SINVEC2 2DEC .2462117800 # = SIN(29.5) $2
020727,000552:
020728,000553: 26,2403 04343 21616 VECANG1 2DEC .1388888889 # = 50 DEGREES $360
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Page 484 |
020730,000555: 26,2405 03070 34344 VECANG2 2DEC .09722222222 # = 35 DEGREES $360
020731,000556:
020732,000557: 26,2407 00000 1BITDP OCT 0 # KEEP THIS BEFORE DPB(-14) ************
020733,000558: 26,2410 00001 DPB-14 OCT 00001
020734,000559: 26,2411 00000 OCT 00000
020735,000560:
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Page 485 |
020737,000562: # ROUTINE FOR INITIATING AUTOMATIC MANEUVER VIA KEYBOARD (V49)
020738,000563:
020739,000564: 34,2000 BANK 34
020740,000565: 23,2000 SETLOC R62
020741,000566: 23,2000 BANK
020742,000567: 23,2103 E6,1676 EBANK= BCDU
020743,000568:
020744,000569: 23,2103 COUNT* $$/R62
020745,000570:
020746,000571: 23,2103 23,2103 R62DISP EQUALS R62FLASH
020747,000572:
020748,000573: 23,2103 35010 R62FLASH CAF V06N22 # FLASH V06N22 AND
020749,000574: 23,2104 04616 TC BANKCALL # ICDU ANGLES
020750,000575: 23,2105 20476 CADR GOFLASH
020751,000576: 23,2106 15472 TCF ENDEXT # TERMINATE
020752,000577: 23,2107 12111 TCF GOMOVE # PROCEED
020753,000578: 23,2110 12103 TCF R62FLASH # ENTER
020754,000579:
020755,000580: # ASTRONAUT MAY LOAD NEW ICDUS AT THIS
020756,000581: # POINT.
020757,000582: 23,2111 05504 GOMOVE TC UPFLAG # SET FOR 3-AXIS MANEUVER
020758,000583: 23,2112 00124 ADRES 3AXISFLG
020759,000584:
020760,000585: 23,2113 04616 TC BANKCALL
020761,000586: 23,2114 54123 CADR R60LEM
020762,000587: 23,2115 15472 TCF ENDEXT # END R62
020763,000588:
End of include-file R60_62.agc. Parent file is MAIN.agc