Source Code
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These source-code files derive from a printout of Luminary 116 (the Apollo 12
Lunar Module guidance computer program), from the personal library of
original AGC developer Don Eyles, digitally photographed at archive.org,
financially sponsored by Ron Burkey, and transcribed to source code by a
team of volunteers. This colorized, syntax-highlighted form was created
by assembling that transcribed source code. Note that the full page images
are available on the
Virtual AGC project page at archive.org, while reduced-size images
are presented at the VirtualAGC project website. Report or fix any
transcription errors at
the Virtual AGC project code repository. Notations on the program listing read, in part: GAP: ASSEMBLE REVISION 116 OF AGC PROGRAM LUMINARY BY NASA 2021112-071 19:09 AUG. 11,1969Note that the date is the date of the printout, not the date of the program revision. |
020232,000002: ## Copyright: Public domain.
020233,000003: ## Filename: R60,R62.agc
020234,000004: ## Purpose: A section of Luminary revision 116.
020235,000005: ## It is part of the source code for the Lunar Module's (LM)
020236,000006: ## Apollo Guidance Computer (AGC) for Apollo 12.
020237,000007: ## This file is intended to be a faithful transcription, except
020238,000008: ## that the code format has been changed to conform to the
020239,000009: ## requirements of the yaYUL assembler rather than the
020240,000010: ## original YUL assembler.
020241,000011: ## Reference: pp. 474-487
020242,000012: ## Assembler: yaYUL
020243,000013: ## Contact: Ron Burkey <info@sandroid.org>.
020244,000014: ## Website: www.ibiblio.org/apollo/index.html
020245,000015: ## Mod history: 2017-01-22 MAS Created from Luminary 99.
020246,000016: ## 2017-01-27 RSB Back-ported a comment-text fix identified in Luminary 69.
020247,000017: ## 2017-03-09 RSB Transcribed, and then proofed comment-text using
020248,000018: ## 3-way diff vs Luminary 99 and Luminary 131.
020249,000019: ## (Admittedly, the former is more for detecting errors
020250,000020: ## in Luminary 99 than the other way around.)
020251,000021:
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Page 474 |
020253,000023: # MOD NO: 0 DATE: 1 MAY 1968
020254,000024: # MOD BY: DIGITAL DEVEL GROUP LOG SECTION R60,R62
020255,000025:
020256,000026: # FUNCTIONAL DESCRIPTION:
020257,000027:
020258,000028: # CALLED AS A GENERAL SUBROUTINE TO MANEUVER THE LM TO A SPECIFIED
020259,000029: # ATTITUDE.
020260,000030:
020261,000031: # 1. IF THE 3-AXIS FLAG IS NOT SET THE FINAL CDU ANGLES ARE
020262,000032: # CALCULATED (VECPOINT).
020263,000033:
020264,000034: # 2. THE FDAI BALL ANGLES (NOUN 18) ARE CALCULATED (BALLANGS).
020265,000035:
020266,000036: # 3. REQUEST FLASHING DISPLAY V50 N18 PLEASE PERFORM AUTO MANEUVER.
020267,000037:
020268,000038: # 4. IF PRIORITY DISPLAY FLAG IS SET DO A PHASECHANGE. THEN AWAIT
020269,000039: # ASTRONAUT RESPONSE.
020270,000040:
020271,000041: # 5. DISPLAY RESPONSE RETURNS:
020272,000042:
020273,000043: # A. ENTER - RESET 3-AXIS FLAG AND RETURN TO CLIENT.
020274,000044:
020275,000045: # B. TERMINATE - IF IN P00 GO TO STEP 5A. OTHERWISE CHECK IF R61 IS
020276,000046: # THE CALLING PROGRAM. IF IN R61 AN EXIT IS MADE TO GOTOV56. IF
020277,000047: # NOT IN R61 AN EXIT IS DONE VIA GOTOP00H.
020278,000048:
020279,000049: # C. PROCEED - CONTINUE WITH PROGRAM AT STEP 6.
020280,000050:
020281,000051: # 6. IF THE 3-AXISFLAG IS NOT SET, THE FINAL CDU ANGLES ARE CALCULATED
020282,000052: # (VECPOINT).
020283,000053:
020284,000054: # 7. THE FDAI BALL ANGLES (NOUN 18) ARE CALCULATED (BALLANGS).
020285,000055:
020286,000056: # 8. IF THE G+N SWITCH IS NOT SET GO BACK TO STEP 3.
020287,000057: #
020288,000058: # 9. IF THE AUTO SWITCH IS NOT SET GO BACK TO STEP 3.
020289,000059:
020290,000060: # 10. NONFLASHING DISPLAY V06N18 (FDAI ANGLES).
020291,000061:
020292,000062: # 11. DO A PHASECHANGE.
020293,000063:
020294,000064: # 12. DO A MANEUVER CALCULATION AND ICDU DRIVE ROUTINE TO ACHIEVE FINAL
020295,000065:
020296,000066: # GIMBAL ANGLES (GOMANUR).
020297,000067: # 13. AT END OF MANEUVER GO TO STEP 3.
020298,000068:
020299,000069: # IF SATISFACTORY MANEUVER STEP 5A EXITS R60.
020300,000070: # FOR FURTHER ADJUSTMENT OF THE VEHICLE ATTITUDE ABOUT THE
020301,000071: # DESIRED VECTOR, THE ROUTINE MAY BE PERFORMED AGAIN STARTING AT
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020303,000073: # STEP 5C.
020304,000074:
020305,000075: # CALLING SEQUENCE: TC BANKCALL
020306,000076: # CADR R60LEM
020307,000077:
020308,000078: # ERASABLE INITIALIZATION REQUIRED: SCAXIS, POINTVSM (FOR VECPOINT)
020309,000079: # 3AXISFLG.
020310,000080:
020311,000081: # SUBROUTINES CALLED: VECPOINT, BALLANGS, GOPERF2R, LINUS, GODSPER,
020312,000082: # GOMANUR, DOWNFLAG, PHASCHNG, UPFLAG
020313,000083:
020314,000084: # NORMAL EXIT MODES: CAE TEMPR60 (CALLERS RETURN ADDRESS)
020315,000085: # TC BANKJUMP
020316,000086:
020317,000087: # ALARMS: NONE
020318,000088:
020319,000089: # OUTPUT: NONE
020320,000090:
020321,000091: # DEBRIS: CPHI, CTHETA, CPSI, 3AXISFLG, TBASE2
020322,000092:
020323,000093: 34,2000 BANK 34
020324,000094: 26,2000 SETLOC MANUVER
020325,000095: 26,2000 BANK
020326,000096:
020327,000097: 26,2123 1163 EBANK= TEMPR60
020328,000098:
020329,000099: 26,2123 COUNT* $$/R06
020330,000100: 26,2123 04645 R60LEM TC MAKECADR
020331,000101: 26,2124 55163 TS TEMPR60
020332,000102:
020333,000103: 26,2125 05504 TC UPFLAG # INSURE THAT TOTAL ATTITUDE ERRORS ARE
020334,000104: 26,2126 00013 ADRES NEEDLFLG # DISPLAYED ON FDAI ERROR NEEDLES.
020335,000105: 26,2127 05516 TC DOWNFLAG
020336,000106: 26,2130 00000 ADRES NEED2FLG
020337,000107:
020338,000108: 26,2131 34746 REDOMANN CAF 3AXISBIT
020339,000109: 26,2132 70101 MASK FLAGWRD5 # IS 3-AXIS FLAG SET
020340,000110: 26,2133 10000 CCS A
020341,000111: 26,2134 12142 TCF TOBALL # YES
020342,000112: 26,2135 06042 TC INTPRET
020343,000113: 26,2136 77624 CALL
020344,000114: 26,2137 56040 VECPOINT # TO COMPUTE FINAL ANGLES
020345,000115: 26,2140 00322 STORE CPHI # STORE FINAL ANGLES - CPHI, CTHETA, CPSI
020346,000116: 26,2141 77776 EXIT
020347,000117:
020348,000118: 26,2142 04616 TOBALL TC BANKCALL
020349,000119: 26,2143 54272 CADR BALLANGS # TO CONVERT ANGLES TO FDAI
020350,000120: 26,2144 32260 TOBALLA CAF V06N18
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020352,000122: 26,2145 04616 TC BANKCALL
020353,000123: 26,2146 20711 CADR GOPERF2R # DISPLAY PLEASE PERFORM AUTO MANEUVER
020354,000124: 26,2147 02246 TC R61TEST
020355,000125: 26,2150 02154 TC REDOMANC # PROCEED
020356,000126: 26,2151 02201 TC ENDMANU1 # ENTER I.E. FINISHED WITH R60
020357,000127: 26,2152 02205 TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
020358,000128: 26,2153 05155 TC ENDOFJOB
020359,000129:
020360,000130: 26,2154 34746 REDOMANC CAF 3AXISBIT
020361,000131: 26,2155 70101 MASK FLAGWRD5 # IS 3-AXIS FLAG SET
020362,000132: 26,2156 10000 CCS A
020363,000133: 26,2157 12165 TCF TOBALLC # YES
020364,000134: 26,2160 06042 TC INTPRET
020365,000135: 26,2161 77624 CALL
020366,000136: 26,2162 56040 VECPOINT # TO COMPUTE FINAL ANGLES
020367,000137: 26,2163 00322 STORE CPHI # STORE ANGLES
020368,000138: 26,2164 77776 EXIT
020369,000139:
020370,000140: 26,2165 04616 TOBALLC TC BANKCALL
020371,000141: 26,2166 54272 CADR BALLANGS # TO CONVERT ANGLES TO FDAI
020372,000142: 26,2167 02261 TC G+N,AUTO # CHECK AUTO MODE
020373,000143: 26,2170 10000 CCS A
020374,000144: 26,2171 12144 TCF TOBALLA # NOT AUTO, GO REREQUEST AUTO MANEUVER.
020375,000145:
020376,000146: 26,2172 32260 AUTOMANV CAF V06N18 # STATIC DISPLAY DURING AUTO MANEUVER
020377,000147: 26,2173 04616 TC BANKCALL # -
020378,000148: 26,2174 20452 CADR GODSPR # -
020379,000149: 26,2175 02205 TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
020380,000150:
020381,000151: 26,2176 04616 STARTMNV TC BANKCALL # PERFORM MANEUVER VIA KALCMANU
020382,000152: 26,2177 17742 CADR GOMANUR
020383,000153:
020384,000154: 26,2200 12144 ENDMANUV TCF TOBALLA # FINISHED MANEUVER.
020385,000155: 26,2201 05516 ENDMANU1 TC DOWNFLAG # RESET 3-AXIS FLAG
020386,000156: 26,2202 00124 ADRES 3AXISFLG
020387,000157: 26,2203 31163 CAE TEMPR60 # -
020388,000158: 26,2204 04640 TC BANKJUMP # -
020389,000159:
020390,000160: 26,2205 40100 CHKLINUS CS FLAGWRD4
020391,000161: 26,2206 74740 MASK PDSPFBIT # IS PRIORITY DISPLAY FLAG SET?
020392,000162: 26,2207 10000 CCS A # -
020393,000163: 26,2210 00002 TC Q # NO - EXIT
020394,000164: 26,2211 30002 CA Q
020395,000165: 26,2212 54156 TS MPAC +2 # SAVE RETURN
020396,000166: 26,2213 46250 CS THREE # OBTAIN LOCATION FOR RESTART
020397,000167: 26,2214 60133 AD BUF2 # HOLDS Q OF LAST DISPLAY
020398,000168: 26,2215 55054 TS TBASE2
020399,000169:
020400,000170: 26,2216 05353 TC PHASCHNG
020401,000171: 26,2217 00132 OCT 00132
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020403,000173:
020404,000174: 26,2220 34745 CAF BIT7
020405,000175: 26,2221 05464 TC LINUS # GO SET BITS FOR PRIORITY DISPLAY -
020406,000176: 26,2222 00156 TC MPAC +2
020407,000177:
020408,000178: 26,2223 37717 RELINUS CAF PRIO26 # RESTORE ORIGINAL PRIORITY
020409,000179: 26,2224 05146 TC PRIOCHNG
020410,000180:
020411,000181: 26,2225 34747 CAF TRACKBIT # DON'T CONTINUE R60 UNLESS TRACKFLAG ON.
020412,000182: 26,2226 70075 MASK FLAGWRD1
020413,000183: 26,2227 10000 CCS A
020414,000184: 26,2230 12243 TCF RER60
020415,000185:
020416,000186: 26,2231 34745 CAF RNDVZBIT # IS IT P20?
020417,000187: 26,2232 70074 MASK FLAGWRD0
020418,000188: 26,2233 10000 CCS A
020419,000189: 26,2234 02240 TC +4 # YES
020420,000190: 26,2235 05353 TC PHASCHNG # NO, MUST BE P25, SET 2.11 SPOT
020421,000191: 26,2236 40112 OCT 40112
020422,000192:
020423,000193: 26,2237 05155 TC ENDOFJOB
020424,000194:
020425,000195: 26,2240 05353 TC PHASCHNG # SET 2.7 SPOT FOR P20
020426,000196: 26,2241 40072 OCT 40072
020427,000197:
020428,000198: 26,2242 05155 TC ENDOFJOB
020429,000199:
020430,000200: 26,2243 05504 RER60 TC UPFLAG # SET PRIO DISPLAY FLAG AFTER RESTART
020431,000201: 26,2244 00077 ADRES PDSPFLAG
020432,000202:
020433,000203: 26,2245 01054 TC TBASE2
020434,000204:
020435,000205: 26,2246 31010 R61TEST CA MODREG # IF WE ARE IN P00 IT MUST BE V49 OR V89
020436,000206: 26,2247 00006 EXTEND
020437,000207: 26,2250 12201 BZF ENDMANU1 # THUS WE GO TO ENDEXT VIA USER
020438,000208:
020439,000209: 26,2251 30100 CA FLAGWRD4 # ARE WE IN R61 (P20 OR P25)
020440,000210: 26,2252 74740 MASK PDSPFBIT
020441,000211: 26,2253 00006 EXTEND
020442,000212: 26,2254 16001 BZF GOTOPOOH # NO
020443,000213: 26,2255 06025 TC GOTOV56 # YES
020444,000214:
020445,000215: 26,2256 20100 BIT14+7 OCT 20100 # -
020446,000216: 26,2257 00203 OCT203 OCT 203
020447,000217: 26,2260 01422 V06N18 VN 0618
020448,000218: # SUBROUTINE TO CHECK FOR G+N CONTROL, AUTO STABILIZATION
020449,000219:
020450,000220: # RETURNS WITH C(A) = + IF NOT SET FOR G+N, AUTO
020451,000221: # RETURNS WITH C(A) = +0 IF SWITCHES ARE SET
020452,000222:
020453,000223: 26,2261 00006 G+N,AUTO EXTEND
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020455,000225: 26,2262 00030 READ CHAN30
020456,000226: 26,2263 74742 MASK BIT10
020457,000227: 26,2264 10000 CCS A
020458,000228: 26,2265 00002 TC Q # NOT IN G+N C(A) = +
020459,000229: 26,2266 00006 ISITAUTO EXTEND # CHECK FOR AUTO MODE
020460,000230: 26,2267 00031 READ CHAN31
020461,000231: 26,2270 74736 MASK BIT14
020462,000232: 26,2271 00002 TC Q # (+) = NOT IN AUTO, (+0) = AOK
020463,000233:
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020465,000235: # PROGRAM DESCRIPTION BALLANGS
020466,000236: # MOD NO. LOG SECTION R60,R62
020467,000237:
020468,000238: # WRITTEN BY RAMA M. AIYAWAR
020469,000239:
020470,000240: # FUNCTIONAL DESCRIPTION
020471,000241:
020472,000242: # COMPUTES LM FDAI BALL DISPLAY ANGLES
020473,000243:
020474,000244: # CALLING SEQUENCE
020475,000245:
020476,000246: # TC BALLANGS
020477,000247:
020478,000248: # NORMAL EXIT MODE
020479,000249:
020480,000250: # TC BALLEXIT (SAVED Q)
020481,000251:
020482,000252: # ALARM OR EXIT MODE NIL
020483,000253:
020484,000254: # SUBROUTINES CALLED
020485,000255:
020486,000256: # CD*TR*G
020487,000257: # ARCTAN
020488,000258:
020489,000259: # INPUT
020490,000260:
020491,000261: # CPHI,CTHETA,CPSI ARE THE ANGLES CORRESPONDING TO AOG, AIG, AMG. THEY ARE
020492,000262: # SP,2S COMPLIMENT SCALED TO HALF REVOLUTION.
020493,000263:
020494,000264: # OUTPUT
020495,000265:
020496,000266: # FDAIX, FDAIY, FDAIZ ARE THE REQUIRED BALL ANGLES SCALED TO HALF REVOLUTION
020497,000267: # SP,2S COMPLIMENT.
020498,000268:
020499,000269: # THESE ANGLES WILL BE DISPLAYED AS DEGREES AND HUNDREDTHS, IN THE ORDER ROLL, PITCH, YAW, USING NOUNS 18 & 19.
020500,000270:
020501,000271: # ERASABLE INITIALIZATION REQUIRED
020502,000272:
020503,000273: # CPHI, CTHETA, CPSI EACH A SP REGISTER
020504,000274:
020505,000275: # DEBRIS
020506,000276:
020507,000277: # A,L,Q,MPAC,SINCDU,COSCDU,PUSHLIST,BALLEXIT
020508,000278:
020509,000279: # NOMENCLATURE: CPHI, CTHETA, & CPSI REPRESENT THE OUTER, INNER, & MIDDLE GIMBAL ANGLES, RESPECTIVELY; OR
020510,000280: # EQUIVALENTLY, CDUX, CDUY, & CDUZ.
020511,000281:
020512,000282: # NOTE: ARCTAN CHECKS FOR OVERFLOW AND SHOULD BE ABLE TO HANDLE ANY SINGULARITIES.
020513,000283:
020514,000284: 26,2000 SETLOC BAWLANGS
020515,000285: 26,2000 BANK
020516,000286:
020517,000287: 26,2272 COUNT* $$/BALL
020518,000288: 26,2272 04645 BALLANGS TC MAKECADR
020519,000289: 26,2273 55337 TS BALLEXIT
020520,000290: 26,2274 30321 CA CPHI
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020522,000292: 26,2275 54771 TS CDUSPOT +4
020523,000293: 26,2276 30322 CA CTHETA
020524,000294: 26,2277 54765 TS CDUSPOT
020525,000295: 26,2300 30323 CA CPSI
020526,000296: 26,2301 54767 TS CDUSPOT +2
020527,000297:
020528,000298: 26,2302 06042 TC INTPRET
020529,000299: 26,2303 45001 SETPD CALL
020530,000300: 26,2304 00001 0D
020531,000301: 26,2305 47545 CD*TR*G
020532,000302:
020533,000303: 26,2306 41345 DLOAD DMP
020534,000304: 26,2307 00742 SINCDUX # SIN (OGA)
020535,000305: 26,2310 00746 COSCDUZ # COS (MGA)
020536,000306:
020537,000307: 26,2311 57552 SL1 DCOMP # SCALE
020538,000308: 26,2312 65336 ARCSIN PDDL # YAW = ARCSIN(-SXCZ) INTO 0 PD
020539,000309: 26,2313 00740 SINCDUZ
020540,000310: 26,2314 14023 STODL SINTH # (SINTH = 18D IN PD)
020541,000311: 26,2315 00746 COSCDUZ
020542,000312: 26,2316 72405 DMP SL1 # RESCALE
020543,000313: 26,2317 00750 COSCDUX
020544,000314: 26,2320 34021 STCALL COSTH # (COSTH = 16D IN PD)
020545,000315: 26,2321 26510 ARCTAN
020546,000316: 26,2322 41325 PDDL DMP # ROLL = ARCTAN(SZ/CZCX) INTO 2 PD
020547,000317: 26,2323 00740 SINCDUZ
020548,000318: 26,2324 00742 SINCDUX
020549,000319: 26,2325 41512 SL2 PUSH # SXSZ INTO 4 PD
020550,000320: 26,2326 65205 DMP PDDL # SXSZCY INTO 4 PD
020551,000321: 26,2327 00744 COSCDUY
020552,000322: 26,2330 65205 DMP PDDL # SXSZSY INTO 6 PD
020553,000323: 26,2331 00736 SINCDUY
020554,000324: 26,2332 00750 COSCDUX
020555,000325: 26,2333 72405 DMP SL1 # CXCY
020556,000326: 26,2334 00744 COSCDUY
020557,000327: 26,2335 45425 DSU STADR # PULL UP FROM 6 PD
020558,000328: 26,2336 63756 STODL COSTH # COSTH = CXCY - SXSZSY
020559,000329: 26,2337 00736 SINCDUY
020560,000330: 26,2340 72405 DMP SL1
020561,000331: 26,2341 00750 COSCDUX # CXSY
020562,000332: 26,2342 45415 DAD STADR # PULL UP FROM 4 PD
020563,000333: 26,2343 43754 STCALL SINTH # SINTH = CXSY + SXSZCY
020564,000334: 26,2344 26510 ARCTAN # RETURNS WITH D(MPAC) = PITCH
020565,000335: 26,2345 55525 PDDL VDEF # PITCH INTO 2 PD, ROLL INTO MPAC FROM 2 PD
020566,000336: 26,2346 77634 RTB # VDEF MAKES V(MPAC) = ROLL, PITCH, YAW
020567,000337: 26,2347 21621 V1STO2S
020568,000338: 26,2350 02345 STORE FDAIX # MODE IS TP
020569,000339: 26,2351 77776 EXIT
020570,000340:
020571,000341: 26,2352 31337 ENDBALL CA BALLEXIT
020572,000342:
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020574,000344: 26,2353 04640 TC BANKJUMP
020575,000345:
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020577,000347: # PROGRAM DESCRIPTION - VECPOINT
020578,000348:
020579,000349: # THIS INTERPRETIVE SUBROUTINE MAY BE USED TO POINT A SPACECRAFT AXIS IN A DESIRED DIRECTION. THE AXIS
020580,000350: # TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN SUCCESSIVE LOCATIONS OF ERASABLE MEMORY
020581,000351: # BEGINNING WITH THE LOCATION CALLED SCAXIS. THE COMPONENTS OF THIS VECTOR ARE GIVEN IN SPACECRAFT COORDINATES.
020582,000352: # THE DIRECTION IN WHICH THIS AXIS IS TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN
020583,000353: # SUCCESSIVE LOCATIONS OF ERASABLE MEMORY BEGINNING WITH THE ADDRESS CALLED POINTVSM. THE COMPONENTS OF THIS
020584,000354: # VECTOR ARE GIVEN IN STABLE MEMBER COORDINATES. WITH THIS INFORMATION VECPOINT COMPUTES A SET OF THREE GIMBAL
020585,000355: # ANGLES (2S COMPLEMENT) CORESPONDING TO THE CROSS-PRODUCT ROTATION BETWE EN SCAXIS AND POINTVSM AND STORES THEM
020586,000356: # IN T(MPAC) BEFORE RETURNING TO THE CALLER.
020587,000357:
020588,000358: # THIS ROTATION, HOWEVER, MAY BRING THE S/C INTO GIMBAL LOCK. WHEN POINTING A VECTOR IN THE Y-Z PLANE,
020589,000359: # THE TRANSPONDER AXIS, OR THE AOT FOR THE LEM, THE PROGRAM WILL CORRECT THIS PROBLEM BY ROTATING THE CROSS-
020590,000360: # PRODUCT ATTITUDE ABOUT POINTVSM BY A FIXED AMOUNT SUFFICIENT TO ROTATE THE DESIRED S/C ATTITUDE OUT OF GIMBAL
020591,000361: # 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,
020592,000362: # THE ADDITIONAL ROTATION TO AVOID GIMAL LOCK IS 35 DEGREES. IF THE AXIS IS MORE THAN 60.5 DEGEES FROM +X (OR -X)
020593,000363: # THE ADDITIONAL ROTATION IS 35 DEGREES. THE GIMBAL ANGLES CORRESPONDING TO THIS ATTITUDE ARE THEN COMPUTED AND
020594,000364: # STORED AS 2S COMPLIMENT ANGLES IN T(MPAC) BEFORE RETURNING TO THE CALLER.
020595,000365:
020596,000366: # WHEN POINTING THE X-AXIS, OR THE THRUST VECTOR, OR ANY VECTOR WITHIN 40.6 DEG OF THE X-AXIS, VECPOINT
020597,000367: # CANNOT CORRECT FOR A CROSS-PRODUCT ROTATION INTO GIMBAL LOCK. IN THIS CASE A PLATFORM REALIGNMENT WOULD BE
020598,000368: # REQUIRED TO POINT THE VECTOR IN THE DESIRED DIRECTION. AT PRESENT NO INDICATION IS GIVEN FOR THIS SITUATION
020599,000369: # EXCEPT THAT THE FINAL MIDDLE GIMBAL ANGLE IN MPAC +2 IS GREATER THAN 59 DEGREES.
020600,000370:
020601,000371: # CALLING SEQUENCE -
020602,000372:
020603,000373: # 1) LOAD SCAXIS, POINTVSM
020604,000374: # 2) CALL
020605,000375: # VECPOINT
020606,000376:
020607,000377: # RETURNS WITH
020608,000378:
020609,000379: # 1) DESIRED OUTER GIMBAL ANGLE IN MPAC
020610,000380: # 2) DESIRED INNER GIMBAL ANGLE IN MPAC +1
020611,000381: # 3) DESIRED MIDDLE GIMBAL ANGLE IN MPAC +2
020612,000382:
020613,000383: # ERASABLES USED -
020614,000384:
020615,000385: # 1) SCAXIS 6
020616,000386: # 2) POINTVSM 6
020617,000387: # 3) MIS 18
020618,000388: # 4) DEL 18
020619,000389: # 5) COF 6
020620,000390: # 6) VECQTEMP 1
020621,000391: # 7) ALL OF VAC AREA 43
020622,000392:
020623,000393: # TOTAL 99
020624,000394:
020625,000395: 27,2000 SETLOC VECPT
020626,000396: 27,2000 BANK
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Page 483 |
020628,000398: 27,2032 COUNT* $$/VECPT
020629,000399:
020630,000400: 27,2032 E6,1676 EBANK= BCDU
020631,000401:
020632,000402: 27,2032 40020 VECPNT1 STQ BOV # THIS ENTRY USES DESIRED CDUS
020633,000403: 27,2033 03325 VECQTEMP # NOT PRESENT - ENTER WITH CDUD'S IN MPAC
020634,000404: 27,2034 56035 VECPNT2
020635,000405: 27,2035 52164 VECPNT2 AXC,2 GOTO
020636,000406: 27,2036 03246 MIS
020637,000407: 27,2037 56046 STORANG
020638,000408: 27,2040 40020 VECPOINT STQ BOV # SAVE RETURN ADDRESS
020639,000409: 27,2041 03325 VECQTEMP
020640,000410: 27,2042 56043 VECLEAR # AND CLEAR OVFIND
020641,000411: 27,2043 47164 VECLEAR AXC,2 RTB
020642,000412: 27,2044 03246 MIS # READ THE PRESENT CDU ANGLES AND
020643,000413: 27,2045 44403 READCDUK # STORE THEM IN PD25, 26, 27
020644,000414: 27,2046 34032 STORANG STCALL 25D
020645,000415: 27,2047 44410 CDUTODCM # S/C AXES TO STABLE MEMBER AXES (MIS)
020646,000416: 27,2050 61375 VLOAD VXM
020647,000417: 27,2051 03773 POINTVSM # RESOLVE THE POINTING DIRECTION VF INTO
020648,000418: 27,2052 03247 MIS # INITIAL S/C AXES (VF = POINTVSM)
020649,000419: 27,2053 77656 UNIT
020650,000420: 27,2054 00035 STORE 28D
020651,000421: # PD 28 29 30 31 32 33
020652,000422: 27,2055 53435 VXV UNIT # TAKE THE CROSS PRODUCT VF X VI
020653,000423: 27,2056 03765 SCAXIS # WHERE VI = SCAXIS
020654,000424: 27,2057 57400 BOV VCOMP
020655,000425: 27,2060 56170 PICKAXIS
020656,000426: 27,2061 17271 STODL COF # CHECK MAGNITUDE
020657,000427: 27,2062 00045 36D # OF CROSS PRODUCT
020658,000428: 27,2063 50025 DSU BMN # VECTOR, IF LESS
020659,000429: 27,2064 14415 DPB-14 # THAN B-14 ASSUME
020660,000430: 27,2065 56170 PICKAXIS # UNIT OPERATION
020661,000431: 27,2066 50375 VLOAD DOT # INVALID.
020662,000432: 27,2067 03765 SCAXIS
020663,000433: 27,2070 00035 28D
020664,000434: 27,2071 65552 SL1 ARCCOS
020665,000435: 27,2072 77624 COMPMATX CALL # NOW COMPUTE THE TRANSFORMATION FROM
020666,000436: 27,2073 44527 DELCOMP # FINAL S/C AXES TO INITIAL S/C AXES MFI
020667,000437: 27,2074 75160 AXC,1 AXC,2
020668,000438: 27,2075 03246 MIS # COMPUTE THE TRANSFORMATION FROM FINAL
020669,000439: 27,2076 02230 KEL # S/C AXES TO STABLE MEMBER AXES
020670,000440: 27,2077 77624 CALL # MFS = MIS MFI
020671,000441: 27,2100 44312 MXM3 # (IN PD LIST)
020672,000442:
020673,000443: 27,2101 51545 DLOAD ABS
020674,000444: 27,2102 00007 6 # MFS6 = SIN(CPSI) $2
020675,000445: 27,2103 50025 DSU BMN
020676,000446: 27,2104 14402 SINGIMLC # = SIN(59 DEGS) $2
020677,000447: 27,2105 56160 FINDGIMB # /CPSI/ LESS THAN 59 DEGS
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Page 484 |
020679,000449: # I.E. DESIRED ATTITUDE NOT IN GIMBAL LOCK
020680,000450:
020681,000451: 27,2106 51545 DLOAD ABS # CHECK TO SEE IF WE ARE POINTING
020682,000452: 27,2107 03765 SCAXIS # THE THRUST AXIS
020683,000453: 27,2110 51025 DSU BPL
020684,000454: 27,2111 14404 SINVEC1 # SIN 49.4 DEGS $2
020685,000455: 27,2112 56160 FINDGIMB # IF SO, WE ARE TRYING TO POINT IT INTO
020686,000456: 27,2113 77775 VLOAD # GIMBAL LOCK, ABORT COULD GO HERE
020687,000457: 27,2114 77626 STADR
020688,000458: 27,2115 50514 STOVL MIS +12D
020689,000459: 27,2116 77626 STADR # STORE MFS (IN PD LIST) IN MIS
020690,000460: 27,2117 50522 STOVL MIS +6
020691,000461: 27,2120 77626 STADR
020692,000462: 27,2121 50530 STOVL MIS
020693,000463: 27,2122 03255 MIS +6 # INNER GIMBAL AXIS IN FINAL S/C AXES
020694,000464: 27,2123 57444 BPL VCOMP # LOCATE THE IG AXIS DIRECTION CLOSEST TO
020695,000465: 27,2124 56125 IGSAMEX # FINAL X S/C AXIS
020696,000466:
020697,000467: 27,2125 50035 IGSAMEX VXV BMN # FIND THE SHORTEST WAY OF ROTATING THE
020698,000468: 27,2126 03765 SCAXIS # S/C OUT OF GIMBAL LOCK BY A ROTATION
020699,000469: 27,2127 56134 U=SCAXIS # ABOUT +- SCAXIS, I.E. IF (IG (SGN MFS3)
020700,000470: # X SCAXIS . XF) LESS THAN 0, U = SCAXIS
020701,000471: # OTHERWISE U = -SCAXIS
020702,000472:
020703,000473: 27,2130 57575 VLOAD VCOMP
020704,000474: 27,2131 03765 SCAXIS
020705,000475: 27,2132 37271 STCALL COF # ROTATE ABOUT -SCAXIS
020706,000476: 27,2133 56137 CHEKAXIS
020707,000477: 27,2134 77775 U=SCAXIS VLOAD
020708,000478: 27,2135 03765 SCAXIS
020709,000479: 27,2136 03271 STORE COF # ROTATE ABOUT + SCAXIS
020710,000480: 27,2137 51545 CHEKAXIS DLOAD ABS
020711,000481: 27,2140 03765 SCAXIS # SEE IF WE ARE POINTING THE AOT
020712,000482: 27,2141 51025 DSU BPL
020713,000483: 27,2142 14406 SINVEC2 # SIN 29.5 DEGS $2
020714,000484: 27,2143 56147 PICKANG1 # IF SO, ROTATE 50 DEGS ABOUT +- SCAXIS
020715,000485: 27,2144 52145 DLOAD GOTO # IF NOT, MUST BE POINTING THE TRANSPONDER
020716,000486: 27,2145 14412 VECANG2 # OR SOME VECTOR IN THE Y, OR Z PLANE
020717,000487: 27,2146 56151 COMPMFSN # IN THIS CASE ROTATE 35 DEGS TO GET OUT
020718,000488: # OF GIMBAL LOCK (VECANG2 $360)
020719,000489: 27,2147 77745 PICKANG1 DLOAD
020720,000490: 27,2150 14410 VECANG1 # = 50 DEGS $360
020721,000491: 27,2151 77624 COMPMFSN CALL
020722,000492: 27,2152 44527 DELCOMP # COMPUTE THE ROTATION ABOUT SCAXIS TO
020723,000493: 27,2153 75160 AXC,1 AXC,2 # BRING MFS OUT OF GIMBAL LOCK
020724,000494: 27,2154 03246 MIS
020725,000495: 27,2155 02230 KEL
020726,000496: 27,2156 77624 CALL # COMPUTE THE NEW TRANSFORMATION FROM
020727,000497: 27,2157 44312 MXM3 # DESIRED S/C AXES TO STABLE MEMBER AXES
020728,000498: # WHICH WILL ALIGN VI WITH VF AND AVOID
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020730,000500: # GIMBAL LOCK
020731,000501: 27,2160 45160 FINDGIMB AXC,1 CALL
020732,000502: 27,2161 00000 0 # EXTRACT THE COMMANDED CDU ANGLES FROM
020733,000503: 27,2162 44654 DCMTOCDU # THIS MATRIX
020734,000504: 27,2163 40234 RTB SETPD
020735,000505: 27,2164 21621 V1STO2S # CONVERT TO 2:S COMPLEMENT
020736,000506: 27,2165 00001 0
020737,000507: 27,2166 77650 GOTO
020738,000508: 27,2167 03325 VECQTEMP # RETURN TO CALLER
020739,000509:
020740,000510: 27,2170 50375 PICKAXIS VLOAD DOT # IF VF X VI = 0, FIND VF . VI
020741,000511: 27,2171 00035 28D
020742,000512: 27,2172 03765 SCAXIS
020743,000513: 27,2173 72240 BMN TLOAD
020744,000514: 27,2174 54354 ROT180
020745,000515: 27,2175 00032 25D
020746,000516: 27,2176 77650 GOTO # IF VF = VI, CDU DESIRED = PRESENT CDU
020747,000517: 27,2177 03325 VECQTEMP # PRESENT CDU ANGLES
020748,000518:
020749,000519: 35,2000 BANK 35
020750,000520: 26,2000 SETLOC MANUVER1
020751,000521: 26,2000 BANK
020752,000522: 26,2354 47375 ROT180 VLOAD VXV # IF VF, VI ANTIPARALLEL, 108 DEG ROTATION
020753,000523: 26,2355 03255 MIS +6 # IS REQUIRED. Y STABLE MEMBER AXIS IN
020754,000524: 26,2356 06522 HIDPHALF # INITIAL S/C AXES.
020755,000525: 26,2357 47256 UNIT VXV # FIND Y(SM) X X(I)
020756,000526: 26,2360 03765 SCAXIS # FIND UNIT(VI X UNIT(Y(SM) X X(I)))
020757,000527: 26,2361 40056 UNIT BOV # I.E. PICK A VECTOR IN THE PLANE OF X(I),
020758,000528: 26,2362 54376 PICKX # Y(SM) PERPENDICULAR TO VI
020759,000529: 26,2363 17271 STODL COF
020760,000530: 26,2364 00045 36D # CHECK MAGNITUDE
020761,000531: 26,2365 50025 DSU BMN # OF THIS VECTOR.
020762,000532: 26,2366 14415 DPB-14 # IF LESS THAN B-14,
020763,000533: 26,2367 54376 PICKX # PICK X-AXIS.
020764,000534: 26,2370 77775 VLOAD
020765,000535: 26,2371 03271 COF
020766,000536: 26,2372 17271 XROT STODL COF
020767,000537: 26,2373 06522 HIDPHALF
020768,000538: 26,2374 77650 GOTO
020769,000539: 26,2375 56072 COMPMATX
020770,000540: 26,2376 52175 PICKX VLOAD GOTO # PICK THE XAXIS IN THIS CASE
020771,000541: 26,2377 06522 HIDPHALF
020772,000542: 26,2400 54372 XROT
020773,000543: 26,2401 15555 35172 SINGIMLC 2DEC .4285836003 # = SIN(59) $2
020774,000544:
020775,000545: 26,2403 14113 36326 SINVEC1 2DEC .3796356537 # = SIN(49.4) $2
020776,000546:
020777,000547: 26,2405 07701 35703 SINVEC2 2DEC .2462117800 # = SIN(29.5) $2
020778,000548:
020779,000549: 26,2407 04343 21616 VECANG1 2DEC .1388888889 # = 50 DEGREES $360
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Page 486 |
020781,000551: 26,2411 03070 34344 VECANG2 2DEC .09722222222 # = 35 DEGREES $360
020782,000552:
020783,000553: 26,2413 00000 1BITDP OCT 0 # KEEP THIS BEFORE DPB(-14) *********
020784,000554: 26,2414 00001 DPB-14 OCT 00001
020785,000555: 26,2415 00000 OCT 00000
020786,000556:
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Page 487 |
020788,000558: # ROUTINE FOR INITIATING AUTOMATIC MANEUVER VIA KEYBOARD (V49)
020789,000559:
020790,000560: 34,2000 BANK 34
020791,000561: 23,2000 SETLOC R62
020792,000562: 23,2000 BANK
020793,000563: 23,2103 E6,1676 EBANK= BCDU
020794,000564:
020795,000565: 23,2103 COUNT* $$/R62
020796,000566:
020797,000567: 23,2103 23,2103 R62DISP EQUALS R62FLASH
020798,000568:
020799,000569: 23,2103 35010 R62FLASH CAF V06N22 # FLASH V06N22 AND
020800,000570: 23,2104 04616 TC BANKCALL # ICDU ANGLES
020801,000571: 23,2105 20477 CADR GOFLASH
020802,000572: 23,2106 15472 TCF ENDEXT # TERMINATE
020803,000573: 23,2107 12111 TCF GOMOVE # PROCEED
020804,000574: 23,2110 12103 TCF R62FLASH # ENTER
020805,000575:
020806,000576: # ASTRONAUT MAY LOAD NEW ICDUS AT THIS
020807,000577: # POINT
020808,000578: 23,2111 05504 GOMOVE TC UPFLAG # SET FOR 3-AXIS MANEUVER
020809,000579: 23,2112 00124 ADRES 3AXISFLG
020810,000580:
020811,000581: 23,2113 04616 TC BANKCALL
020812,000582: 23,2114 54123 CADR R60LEM
020813,000583: 23,2115 15472 TCF ENDEXT # END R62
020814,000584:
End of include-file R60,R62.agc. Parent file is MAIN.agc