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. |
020230,000002: ## Copyright: Public domain.
020231,000003: ## Filename: R60,R62.agc
020232,000004: ## Purpose: A section of Luminary revision 116.
020233,000005: ## It is part of the source code for the Lunar Module's (LM)
020234,000006: ## Apollo Guidance Computer (AGC) for Apollo 12.
020235,000007: ## This file is intended to be a faithful transcription, except
020236,000008: ## that the code format has been changed to conform to the
020237,000009: ## requirements of the yaYUL assembler rather than the
020238,000010: ## original YUL assembler.
020239,000011: ## Reference: pp. 474-487
020240,000012: ## Assembler: yaYUL
020241,000013: ## Contact: Ron Burkey <info@sandroid.org>.
020242,000014: ## Website: www.ibiblio.org/apollo/index.html
020243,000015: ## Mod history: 2017-01-22 MAS Created from Luminary 99.
020244,000016: ## 2017-01-27 RSB Back-ported a comment-text fix identified in Luminary 69.
020245,000017: ## 2017-03-09 RSB Transcribed, and then proofed comment-text using
020246,000018: ## 3-way diff vs Luminary 99 and Luminary 131.
020247,000019: ## (Admittedly, the former is more for detecting errors
020248,000020: ## in Luminary 99 than the other way around.)
020249,000021:
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Page 474 |
020251,000023: # MOD NO: 0 DATE: 1 MAY 1968
020252,000024: # MOD BY: DIGITAL DEVEL GROUP LOG SECTION R60,R62
020253,000025:
020254,000026: # FUNCTIONAL DESCRIPTION:
020255,000027:
020256,000028: # CALLED AS A GENERAL SUBROUTINE TO MANEUVER THE LM TO A SPECIFIED
020257,000029: # ATTITUDE.
020258,000030:
020259,000031: # 1. IF THE 3-AXIS FLAG IS NOT SET THE FINAL CDU ANGLES ARE
020260,000032: # CALCULATED (VECPOINT).
020261,000033:
020262,000034: # 2. THE FDAI BALL ANGLES (NOUN 18) ARE CALCULATED (BALLANGS).
020263,000035:
020264,000036: # 3. REQUEST FLASHING DISPLAY V50 N18 PLEASE PERFORM AUTO MANEUVER.
020265,000037:
020266,000038: # 4. IF PRIORITY DISPLAY FLAG IS SET DO A PHASECHANGE. THEN AWAIT
020267,000039: # ASTRONAUT RESPONSE.
020268,000040:
020269,000041: # 5. DISPLAY RESPONSE RETURNS:
020270,000042:
020271,000043: # A. ENTER - RESET 3-AXIS FLAG AND RETURN TO CLIENT.
020272,000044:
020273,000045: # B. TERMINATE - IF IN P00 GO TO STEP 5A. OTHERWISE CHECK IF R61 IS
020274,000046: # THE CALLING PROGRAM. IF IN R61 AN EXIT IS MADE TO GOTOV56. IF
020275,000047: # NOT IN R61 AN EXIT IS DONE VIA GOTOP00H.
020276,000048:
020277,000049: # C. PROCEED - CONTINUE WITH PROGRAM AT STEP 6.
020278,000050:
020279,000051: # 6. IF THE 3-AXISFLAG IS NOT SET, THE FINAL CDU ANGLES ARE CALCULATED
020280,000052: # (VECPOINT).
020281,000053:
020282,000054: # 7. THE FDAI BALL ANGLES (NOUN 18) ARE CALCULATED (BALLANGS).
020283,000055:
020284,000056: # 8. IF THE G+N SWITCH IS NOT SET GO BACK TO STEP 3.
020285,000057: #
020286,000058: # 9. IF THE AUTO SWITCH IS NOT SET GO BACK TO STEP 3.
020287,000059:
020288,000060: # 10. NONFLASHING DISPLAY V06N18 (FDAI ANGLES).
020289,000061:
020290,000062: # 11. DO A PHASECHANGE.
020291,000063:
020292,000064: # 12. DO A MANEUVER CALCULATION AND ICDU DRIVE ROUTINE TO ACHIEVE FINAL
020293,000065:
020294,000066: # GIMBAL ANGLES (GOMANUR).
020295,000067: # 13. AT END OF MANEUVER GO TO STEP 3.
020296,000068:
020297,000069: # IF SATISFACTORY MANEUVER STEP 5A EXITS R60.
020298,000070: # FOR FURTHER ADJUSTMENT OF THE VEHICLE ATTITUDE ABOUT THE
020299,000071: # DESIRED VECTOR, THE ROUTINE MAY BE PERFORMED AGAIN STARTING AT
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020301,000073: # STEP 5C.
020302,000074:
020303,000075: # CALLING SEQUENCE: TC BANKCALL
020304,000076: # CADR R60LEM
020305,000077:
020306,000078: # ERASABLE INITIALIZATION REQUIRED: SCAXIS, POINTVSM (FOR VECPOINT)
020307,000079: # 3AXISFLG.
020308,000080:
020309,000081: # SUBROUTINES CALLED: VECPOINT, BALLANGS, GOPERF2R, LINUS, GODSPER,
020310,000082: # GOMANUR, DOWNFLAG, PHASCHNG, UPFLAG
020311,000083:
020312,000084: # NORMAL EXIT MODES: CAE TEMPR60 (CALLERS RETURN ADDRESS)
020313,000085: # TC BANKJUMP
020314,000086:
020315,000087: # ALARMS: NONE
020316,000088:
020317,000089: # OUTPUT: NONE
020318,000090:
020319,000091: # DEBRIS: CPHI, CTHETA, CPSI, 3AXISFLG, TBASE2
020320,000092:
020321,000093: 34,2000 BANK 34
020322,000094: 26,2000 SETLOC MANUVER
020323,000095: 26,2000 BANK
020324,000096:
020325,000097: 26,2123 1163 EBANK= TEMPR60
020326,000098:
020327,000099: 26,2123 COUNT* $$/R06
020328,000100: 26,2123 04645 R60LEM TC MAKECADR
020329,000101: 26,2124 55163 TS TEMPR60
020330,000102:
020331,000103: 26,2125 05504 TC UPFLAG # INSURE THAT TOTAL ATTITUDE ERRORS ARE
020332,000104: 26,2126 00013 ADRES NEEDLFLG # DISPLAYED ON FDAI ERROR NEEDLES.
020333,000105: 26,2127 05516 TC DOWNFLAG
020334,000106: 26,2130 00000 ADRES NEED2FLG
020335,000107:
020336,000108: 26,2131 34746 REDOMANN CAF 3AXISBIT
020337,000109: 26,2132 70101 MASK FLAGWRD5 # IS 3-AXIS FLAG SET
020338,000110: 26,2133 10000 CCS A
020339,000111: 26,2134 12142 TCF TOBALL # YES
020340,000112: 26,2135 06042 TC INTPRET
020341,000113: 26,2136 77624 CALL
020342,000114: 26,2137 56040 VECPOINT # TO COMPUTE FINAL ANGLES
020343,000115: 26,2140 00322 STORE CPHI # STORE FINAL ANGLES - CPHI, CTHETA, CPSI
020344,000116: 26,2141 77776 EXIT
020345,000117:
020346,000118: 26,2142 04616 TOBALL TC BANKCALL
020347,000119: 26,2143 54272 CADR BALLANGS # TO CONVERT ANGLES TO FDAI
020348,000120: 26,2144 32260 TOBALLA CAF V06N18
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020350,000122: 26,2145 04616 TC BANKCALL
020351,000123: 26,2146 20711 CADR GOPERF2R # DISPLAY PLEASE PERFORM AUTO MANEUVER
020352,000124: 26,2147 02246 TC R61TEST
020353,000125: 26,2150 02154 TC REDOMANC # PROCEED
020354,000126: 26,2151 02201 TC ENDMANU1 # ENTER I.E. FINISHED WITH R60
020355,000127: 26,2152 02205 TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
020356,000128: 26,2153 05155 TC ENDOFJOB
020357,000129:
020358,000130: 26,2154 34746 REDOMANC CAF 3AXISBIT
020359,000131: 26,2155 70101 MASK FLAGWRD5 # IS 3-AXIS FLAG SET
020360,000132: 26,2156 10000 CCS A
020361,000133: 26,2157 12165 TCF TOBALLC # YES
020362,000134: 26,2160 06042 TC INTPRET
020363,000135: 26,2161 77624 CALL
020364,000136: 26,2162 56040 VECPOINT # TO COMPUTE FINAL ANGLES
020365,000137: 26,2163 00322 STORE CPHI # STORE ANGLES
020366,000138: 26,2164 77776 EXIT
020367,000139:
020368,000140: 26,2165 04616 TOBALLC TC BANKCALL
020369,000141: 26,2166 54272 CADR BALLANGS # TO CONVERT ANGLES TO FDAI
020370,000142: 26,2167 02261 TC G+N,AUTO # CHECK AUTO MODE
020371,000143: 26,2170 10000 CCS A
020372,000144: 26,2171 12144 TCF TOBALLA # NOT AUTO, GO REREQUEST AUTO MANEUVER.
020373,000145:
020374,000146: 26,2172 32260 AUTOMANV CAF V06N18 # STATIC DISPLAY DURING AUTO MANEUVER
020375,000147: 26,2173 04616 TC BANKCALL # -
020376,000148: 26,2174 20452 CADR GODSPR # -
020377,000149: 26,2175 02205 TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
020378,000150:
020379,000151: 26,2176 04616 STARTMNV TC BANKCALL # PERFORM MANEUVER VIA KALCMANU
020380,000152: 26,2177 17742 CADR GOMANUR
020381,000153:
020382,000154: 26,2200 12144 ENDMANUV TCF TOBALLA # FINISHED MANEUVER.
020383,000155: 26,2201 05516 ENDMANU1 TC DOWNFLAG # RESET 3-AXIS FLAG
020384,000156: 26,2202 00124 ADRES 3AXISFLG
020385,000157: 26,2203 31163 CAE TEMPR60 # -
020386,000158: 26,2204 04640 TC BANKJUMP # -
020387,000159:
020388,000160: 26,2205 40100 CHKLINUS CS FLAGWRD4
020389,000161: 26,2206 74740 MASK PDSPFBIT # IS PRIORITY DISPLAY FLAG SET?
020390,000162: 26,2207 10000 CCS A # -
020391,000163: 26,2210 00002 TC Q # NO - EXIT
020392,000164: 26,2211 30002 CA Q
020393,000165: 26,2212 54156 TS MPAC +2 # SAVE RETURN
020394,000166: 26,2213 46250 CS THREE # OBTAIN LOCATION FOR RESTART
020395,000167: 26,2214 60133 AD BUF2 # HOLDS Q OF LAST DISPLAY
020396,000168: 26,2215 55054 TS TBASE2
020397,000169:
020398,000170: 26,2216 05353 TC PHASCHNG
020399,000171: 26,2217 00132 OCT 00132
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020401,000173:
020402,000174: 26,2220 34745 CAF BIT7
020403,000175: 26,2221 05464 TC LINUS # GO SET BITS FOR PRIORITY DISPLAY -
020404,000176: 26,2222 00156 TC MPAC +2
020405,000177:
020406,000178: 26,2223 37717 RELINUS CAF PRIO26 # RESTORE ORIGINAL PRIORITY
020407,000179: 26,2224 05146 TC PRIOCHNG
020408,000180:
020409,000181: 26,2225 34747 CAF TRACKBIT # DON'T CONTINUE R60 UNLESS TRACKFLAG ON.
020410,000182: 26,2226 70075 MASK FLAGWRD1
020411,000183: 26,2227 10000 CCS A
020412,000184: 26,2230 12243 TCF RER60
020413,000185:
020414,000186: 26,2231 34745 CAF RNDVZBIT # IS IT P20?
020415,000187: 26,2232 70074 MASK FLAGWRD0
020416,000188: 26,2233 10000 CCS A
020417,000189: 26,2234 02240 TC +4 # YES
020418,000190: 26,2235 05353 TC PHASCHNG # NO, MUST BE P25, SET 2.11 SPOT
020419,000191: 26,2236 40112 OCT 40112
020420,000192:
020421,000193: 26,2237 05155 TC ENDOFJOB
020422,000194:
020423,000195: 26,2240 05353 TC PHASCHNG # SET 2.7 SPOT FOR P20
020424,000196: 26,2241 40072 OCT 40072
020425,000197:
020426,000198: 26,2242 05155 TC ENDOFJOB
020427,000199:
020428,000200: 26,2243 05504 RER60 TC UPFLAG # SET PRIO DISPLAY FLAG AFTER RESTART
020429,000201: 26,2244 00077 ADRES PDSPFLAG
020430,000202:
020431,000203: 26,2245 01054 TC TBASE2
020432,000204:
020433,000205: 26,2246 31010 R61TEST CA MODREG # IF WE ARE IN P00 IT MUST BE V49 OR V89
020434,000206: 26,2247 00006 EXTEND
020435,000207: 26,2250 12201 BZF ENDMANU1 # THUS WE GO TO ENDEXT VIA USER
020436,000208:
020437,000209: 26,2251 30100 CA FLAGWRD4 # ARE WE IN R61 (P20 OR P25)
020438,000210: 26,2252 74740 MASK PDSPFBIT
020439,000211: 26,2253 00006 EXTEND
020440,000212: 26,2254 16001 BZF GOTOPOOH # NO
020441,000213: 26,2255 06025 TC GOTOV56 # YES
020442,000214:
020443,000215: 26,2256 20100 BIT14+7 OCT 20100 # -
020444,000216: 26,2257 00203 OCT203 OCT 203
020445,000217: 26,2260 01422 V06N18 VN 0618
020446,000218: # SUBROUTINE TO CHECK FOR G+N CONTROL, AUTO STABILIZATION
020447,000219:
020448,000220: # RETURNS WITH C(A) = + IF NOT SET FOR G+N, AUTO
020449,000221: # RETURNS WITH C(A) = +0 IF SWITCHES ARE SET
020450,000222:
020451,000223: 26,2261 00006 G+N,AUTO EXTEND
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020453,000225: 26,2262 00030 READ CHAN30
020454,000226: 26,2263 74742 MASK BIT10
020455,000227: 26,2264 10000 CCS A
020456,000228: 26,2265 00002 TC Q # NOT IN G+N C(A) = +
020457,000229: 26,2266 00006 ISITAUTO EXTEND # CHECK FOR AUTO MODE
020458,000230: 26,2267 00031 READ CHAN31
020459,000231: 26,2270 74736 MASK BIT14
020460,000232: 26,2271 00002 TC Q # (+) = NOT IN AUTO, (+0) = AOK
020461,000233:
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020463,000235: # PROGRAM DESCRIPTION BALLANGS
020464,000236: # MOD NO. LOG SECTION R60,R62
020465,000237:
020466,000238: # WRITTEN BY RAMA M. AIYAWAR
020467,000239:
020468,000240: # FUNCTIONAL DESCRIPTION
020469,000241:
020470,000242: # COMPUTES LM FDAI BALL DISPLAY ANGLES
020471,000243:
020472,000244: # CALLING SEQUENCE
020473,000245:
020474,000246: # TC BALLANGS
020475,000247:
020476,000248: # NORMAL EXIT MODE
020477,000249:
020478,000250: # TC BALLEXIT (SAVED Q)
020479,000251:
020480,000252: # ALARM OR EXIT MODE NIL
020481,000253:
020482,000254: # SUBROUTINES CALLED
020483,000255:
020484,000256: # CD*TR*G
020485,000257: # ARCTAN
020486,000258:
020487,000259: # INPUT
020488,000260:
020489,000261: # CPHI,CTHETA,CPSI ARE THE ANGLES CORRESPONDING TO AOG, AIG, AMG. THEY ARE
020490,000262: # SP,2S COMPLIMENT SCALED TO HALF REVOLUTION.
020491,000263:
020492,000264: # OUTPUT
020493,000265:
020494,000266: # FDAIX, FDAIY, FDAIZ ARE THE REQUIRED BALL ANGLES SCALED TO HALF REVOLUTION
020495,000267: # SP,2S COMPLIMENT.
020496,000268:
020497,000269: # THESE ANGLES WILL BE DISPLAYED AS DEGREES AND HUNDREDTHS, IN THE ORDER ROLL, PITCH, YAW, USING NOUNS 18 & 19.
020498,000270:
020499,000271: # ERASABLE INITIALIZATION REQUIRED
020500,000272:
020501,000273: # CPHI, CTHETA, CPSI EACH A SP REGISTER
020502,000274:
020503,000275: # DEBRIS
020504,000276:
020505,000277: # A,L,Q,MPAC,SINCDU,COSCDU,PUSHLIST,BALLEXIT
020506,000278:
020507,000279: # NOMENCLATURE: CPHI, CTHETA, & CPSI REPRESENT THE OUTER, INNER, & MIDDLE GIMBAL ANGLES, RESPECTIVELY; OR
020508,000280: # EQUIVALENTLY, CDUX, CDUY, & CDUZ.
020509,000281:
020510,000282: # NOTE: ARCTAN CHECKS FOR OVERFLOW AND SHOULD BE ABLE TO HANDLE ANY SINGULARITIES.
020511,000283:
020512,000284: 26,2000 SETLOC BAWLANGS
020513,000285: 26,2000 BANK
020514,000286:
020515,000287: 26,2272 COUNT* $$/BALL
020516,000288: 26,2272 04645 BALLANGS TC MAKECADR
020517,000289: 26,2273 55337 TS BALLEXIT
020518,000290: 26,2274 30321 CA CPHI
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020520,000292: 26,2275 54771 TS CDUSPOT +4
020521,000293: 26,2276 30322 CA CTHETA
020522,000294: 26,2277 54765 TS CDUSPOT
020523,000295: 26,2300 30323 CA CPSI
020524,000296: 26,2301 54767 TS CDUSPOT +2
020525,000297:
020526,000298: 26,2302 06042 TC INTPRET
020527,000299: 26,2303 45001 SETPD CALL
020528,000300: 26,2304 00001 0D
020529,000301: 26,2305 47545 CD*TR*G
020530,000302:
020531,000303: 26,2306 41345 DLOAD DMP
020532,000304: 26,2307 00742 SINCDUX # SIN (OGA)
020533,000305: 26,2310 00746 COSCDUZ # COS (MGA)
020534,000306:
020535,000307: 26,2311 57552 SL1 DCOMP # SCALE
020536,000308: 26,2312 65336 ARCSIN PDDL # YAW = ARCSIN(-SXCZ) INTO 0 PD
020537,000309: 26,2313 00740 SINCDUZ
020538,000310: 26,2314 14023 STODL SINTH # (SINTH = 18D IN PD)
020539,000311: 26,2315 00746 COSCDUZ
020540,000312: 26,2316 72405 DMP SL1 # RESCALE
020541,000313: 26,2317 00750 COSCDUX
020542,000314: 26,2320 34021 STCALL COSTH # (COSTH = 16D IN PD)
020543,000315: 26,2321 26510 ARCTAN
020544,000316: 26,2322 41325 PDDL DMP # ROLL = ARCTAN(SZ/CZCX) INTO 2 PD
020545,000317: 26,2323 00740 SINCDUZ
020546,000318: 26,2324 00742 SINCDUX
020547,000319: 26,2325 41512 SL2 PUSH # SXSZ INTO 4 PD
020548,000320: 26,2326 65205 DMP PDDL # SXSZCY INTO 4 PD
020549,000321: 26,2327 00744 COSCDUY
020550,000322: 26,2330 65205 DMP PDDL # SXSZSY INTO 6 PD
020551,000323: 26,2331 00736 SINCDUY
020552,000324: 26,2332 00750 COSCDUX
020553,000325: 26,2333 72405 DMP SL1 # CXCY
020554,000326: 26,2334 00744 COSCDUY
020555,000327: 26,2335 45425 DSU STADR # PULL UP FROM 6 PD
020556,000328: 26,2336 63756 STODL COSTH # COSTH = CXCY - SXSZSY
020557,000329: 26,2337 00736 SINCDUY
020558,000330: 26,2340 72405 DMP SL1
020559,000331: 26,2341 00750 COSCDUX # CXSY
020560,000332: 26,2342 45415 DAD STADR # PULL UP FROM 4 PD
020561,000333: 26,2343 43754 STCALL SINTH # SINTH = CXSY + SXSZCY
020562,000334: 26,2344 26510 ARCTAN # RETURNS WITH D(MPAC) = PITCH
020563,000335: 26,2345 55525 PDDL VDEF # PITCH INTO 2 PD, ROLL INTO MPAC FROM 2 PD
020564,000336: 26,2346 77634 RTB # VDEF MAKES V(MPAC) = ROLL, PITCH, YAW
020565,000337: 26,2347 21621 V1STO2S
020566,000338: 26,2350 02345 STORE FDAIX # MODE IS TP
020567,000339: 26,2351 77776 EXIT
020568,000340:
020569,000341: 26,2352 31337 ENDBALL CA BALLEXIT
020570,000342:
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020572,000344: 26,2353 04640 TC BANKJUMP
020573,000345:
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020575,000347: # PROGRAM DESCRIPTION - VECPOINT
020576,000348:
020577,000349: # THIS INTERPRETIVE SUBROUTINE MAY BE USED TO POINT A SPACECRAFT AXIS IN A DESIRED DIRECTION. THE AXIS
020578,000350: # TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN SUCCESSIVE LOCATIONS OF ERASABLE MEMORY
020579,000351: # BEGINNING WITH THE LOCATION CALLED SCAXIS. THE COMPONENTS OF THIS VECTOR ARE GIVEN IN SPACECRAFT COORDINATES.
020580,000352: # THE DIRECTION IN WHICH THIS AXIS IS TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN
020581,000353: # SUCCESSIVE LOCATIONS OF ERASABLE MEMORY BEGINNING WITH THE ADDRESS CALLED POINTVSM. THE COMPONENTS OF THIS
020582,000354: # VECTOR ARE GIVEN IN STABLE MEMBER COORDINATES. WITH THIS INFORMATION VECPOINT COMPUTES A SET OF THREE GIMBAL
020583,000355: # ANGLES (2S COMPLEMENT) CORESPONDING TO THE CROSS-PRODUCT ROTATION BETWE EN SCAXIS AND POINTVSM AND STORES THEM
020584,000356: # IN T(MPAC) BEFORE RETURNING TO THE CALLER.
020585,000357:
020586,000358: # THIS ROTATION, HOWEVER, MAY BRING THE S/C INTO GIMBAL LOCK. WHEN POINTING A VECTOR IN THE Y-Z PLANE,
020587,000359: # THE TRANSPONDER AXIS, OR THE AOT FOR THE LEM, THE PROGRAM WILL CORRECT THIS PROBLEM BY ROTATING THE CROSS-
020588,000360: # PRODUCT ATTITUDE ABOUT POINTVSM BY A FIXED AMOUNT SUFFICIENT TO ROTATE THE DESIRED S/C ATTITUDE OUT OF GIMBAL
020589,000361: # 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,
020590,000362: # THE ADDITIONAL ROTATION TO AVOID GIMAL LOCK IS 35 DEGREES. IF THE AXIS IS MORE THAN 60.5 DEGEES FROM +X (OR -X)
020591,000363: # THE ADDITIONAL ROTATION IS 35 DEGREES. THE GIMBAL ANGLES CORRESPONDING TO THIS ATTITUDE ARE THEN COMPUTED AND
020592,000364: # STORED AS 2S COMPLIMENT ANGLES IN T(MPAC) BEFORE RETURNING TO THE CALLER.
020593,000365:
020594,000366: # WHEN POINTING THE X-AXIS, OR THE THRUST VECTOR, OR ANY VECTOR WITHIN 40.6 DEG OF THE X-AXIS, VECPOINT
020595,000367: # CANNOT CORRECT FOR A CROSS-PRODUCT ROTATION INTO GIMBAL LOCK. IN THIS CASE A PLATFORM REALIGNMENT WOULD BE
020596,000368: # REQUIRED TO POINT THE VECTOR IN THE DESIRED DIRECTION. AT PRESENT NO INDICATION IS GIVEN FOR THIS SITUATION
020597,000369: # EXCEPT THAT THE FINAL MIDDLE GIMBAL ANGLE IN MPAC +2 IS GREATER THAN 59 DEGREES.
020598,000370:
020599,000371: # CALLING SEQUENCE -
020600,000372:
020601,000373: # 1) LOAD SCAXIS, POINTVSM
020602,000374: # 2) CALL
020603,000375: # VECPOINT
020604,000376:
020605,000377: # RETURNS WITH
020606,000378:
020607,000379: # 1) DESIRED OUTER GIMBAL ANGLE IN MPAC
020608,000380: # 2) DESIRED INNER GIMBAL ANGLE IN MPAC +1
020609,000381: # 3) DESIRED MIDDLE GIMBAL ANGLE IN MPAC +2
020610,000382:
020611,000383: # ERASABLES USED -
020612,000384:
020613,000385: # 1) SCAXIS 6
020614,000386: # 2) POINTVSM 6
020615,000387: # 3) MIS 18
020616,000388: # 4) DEL 18
020617,000389: # 5) COF 6
020618,000390: # 6) VECQTEMP 1
020619,000391: # 7) ALL OF VAC AREA 43
020620,000392:
020621,000393: # TOTAL 99
020622,000394:
020623,000395: 27,2000 SETLOC VECPT
020624,000396: 27,2000 BANK
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Page 483 |
020626,000398: 27,2032 COUNT* $$/VECPT
020627,000399:
020628,000400: 27,2032 E6,1676 EBANK= BCDU
020629,000401:
020630,000402: 27,2032 40020 VECPNT1 STQ BOV # THIS ENTRY USES DESIRED CDUS
020631,000403: 27,2033 03325 VECQTEMP # NOT PRESENT - ENTER WITH CDUD'S IN MPAC
020632,000404: 27,2034 56035 VECPNT2
020633,000405: 27,2035 52164 VECPNT2 AXC,2 GOTO
020634,000406: 27,2036 03246 MIS
020635,000407: 27,2037 56046 STORANG
020636,000408: 27,2040 40020 VECPOINT STQ BOV # SAVE RETURN ADDRESS
020637,000409: 27,2041 03325 VECQTEMP
020638,000410: 27,2042 56043 VECLEAR # AND CLEAR OVFIND
020639,000411: 27,2043 47164 VECLEAR AXC,2 RTB
020640,000412: 27,2044 03246 MIS # READ THE PRESENT CDU ANGLES AND
020641,000413: 27,2045 44403 READCDUK # STORE THEM IN PD25, 26, 27
020642,000414: 27,2046 34032 STORANG STCALL 25D
020643,000415: 27,2047 44410 CDUTODCM # S/C AXES TO STABLE MEMBER AXES (MIS)
020644,000416: 27,2050 61375 VLOAD VXM
020645,000417: 27,2051 03773 POINTVSM # RESOLVE THE POINTING DIRECTION VF INTO
020646,000418: 27,2052 03247 MIS # INITIAL S/C AXES (VF = POINTVSM)
020647,000419: 27,2053 77656 UNIT
020648,000420: 27,2054 00035 STORE 28D
020649,000421: # PD 28 29 30 31 32 33
020650,000422: 27,2055 53435 VXV UNIT # TAKE THE CROSS PRODUCT VF X VI
020651,000423: 27,2056 03765 SCAXIS # WHERE VI = SCAXIS
020652,000424: 27,2057 57400 BOV VCOMP
020653,000425: 27,2060 56170 PICKAXIS
020654,000426: 27,2061 17271 STODL COF # CHECK MAGNITUDE
020655,000427: 27,2062 00045 36D # OF CROSS PRODUCT
020656,000428: 27,2063 50025 DSU BMN # VECTOR, IF LESS
020657,000429: 27,2064 14415 DPB-14 # THAN B-14 ASSUME
020658,000430: 27,2065 56170 PICKAXIS # UNIT OPERATION
020659,000431: 27,2066 50375 VLOAD DOT # INVALID.
020660,000432: 27,2067 03765 SCAXIS
020661,000433: 27,2070 00035 28D
020662,000434: 27,2071 65552 SL1 ARCCOS
020663,000435: 27,2072 77624 COMPMATX CALL # NOW COMPUTE THE TRANSFORMATION FROM
020664,000436: 27,2073 44527 DELCOMP # FINAL S/C AXES TO INITIAL S/C AXES MFI
020665,000437: 27,2074 75160 AXC,1 AXC,2
020666,000438: 27,2075 03246 MIS # COMPUTE THE TRANSFORMATION FROM FINAL
020667,000439: 27,2076 02230 KEL # S/C AXES TO STABLE MEMBER AXES
020668,000440: 27,2077 77624 CALL # MFS = MIS MFI
020669,000441: 27,2100 44312 MXM3 # (IN PD LIST)
020670,000442:
020671,000443: 27,2101 51545 DLOAD ABS
020672,000444: 27,2102 00007 6 # MFS6 = SIN(CPSI) $2
020673,000445: 27,2103 50025 DSU BMN
020674,000446: 27,2104 14402 SINGIMLC # = SIN(59 DEGS) $2
020675,000447: 27,2105 56160 FINDGIMB # /CPSI/ LESS THAN 59 DEGS
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Page 484 |
020677,000449: # I.E. DESIRED ATTITUDE NOT IN GIMBAL LOCK
020678,000450:
020679,000451: 27,2106 51545 DLOAD ABS # CHECK TO SEE IF WE ARE POINTING
020680,000452: 27,2107 03765 SCAXIS # THE THRUST AXIS
020681,000453: 27,2110 51025 DSU BPL
020682,000454: 27,2111 14404 SINVEC1 # SIN 49.4 DEGS $2
020683,000455: 27,2112 56160 FINDGIMB # IF SO, WE ARE TRYING TO POINT IT INTO
020684,000456: 27,2113 77775 VLOAD # GIMBAL LOCK, ABORT COULD GO HERE
020685,000457: 27,2114 77626 STADR
020686,000458: 27,2115 50514 STOVL MIS +12D
020687,000459: 27,2116 77626 STADR # STORE MFS (IN PD LIST) IN MIS
020688,000460: 27,2117 50522 STOVL MIS +6
020689,000461: 27,2120 77626 STADR
020690,000462: 27,2121 50530 STOVL MIS
020691,000463: 27,2122 03255 MIS +6 # INNER GIMBAL AXIS IN FINAL S/C AXES
020692,000464: 27,2123 57444 BPL VCOMP # LOCATE THE IG AXIS DIRECTION CLOSEST TO
020693,000465: 27,2124 56125 IGSAMEX # FINAL X S/C AXIS
020694,000466:
020695,000467: 27,2125 50035 IGSAMEX VXV BMN # FIND THE SHORTEST WAY OF ROTATING THE
020696,000468: 27,2126 03765 SCAXIS # S/C OUT OF GIMBAL LOCK BY A ROTATION
020697,000469: 27,2127 56134 U=SCAXIS # ABOUT +- SCAXIS, I.E. IF (IG (SGN MFS3)
020698,000470: # X SCAXIS . XF) LESS THAN 0, U = SCAXIS
020699,000471: # OTHERWISE U = -SCAXIS
020700,000472:
020701,000473: 27,2130 57575 VLOAD VCOMP
020702,000474: 27,2131 03765 SCAXIS
020703,000475: 27,2132 37271 STCALL COF # ROTATE ABOUT -SCAXIS
020704,000476: 27,2133 56137 CHEKAXIS
020705,000477: 27,2134 77775 U=SCAXIS VLOAD
020706,000478: 27,2135 03765 SCAXIS
020707,000479: 27,2136 03271 STORE COF # ROTATE ABOUT + SCAXIS
020708,000480: 27,2137 51545 CHEKAXIS DLOAD ABS
020709,000481: 27,2140 03765 SCAXIS # SEE IF WE ARE POINTING THE AOT
020710,000482: 27,2141 51025 DSU BPL
020711,000483: 27,2142 14406 SINVEC2 # SIN 29.5 DEGS $2
020712,000484: 27,2143 56147 PICKANG1 # IF SO, ROTATE 50 DEGS ABOUT +- SCAXIS
020713,000485: 27,2144 52145 DLOAD GOTO # IF NOT, MUST BE POINTING THE TRANSPONDER
020714,000486: 27,2145 14412 VECANG2 # OR SOME VECTOR IN THE Y, OR Z PLANE
020715,000487: 27,2146 56151 COMPMFSN # IN THIS CASE ROTATE 35 DEGS TO GET OUT
020716,000488: # OF GIMBAL LOCK (VECANG2 $360)
020717,000489: 27,2147 77745 PICKANG1 DLOAD
020718,000490: 27,2150 14410 VECANG1 # = 50 DEGS $360
020719,000491: 27,2151 77624 COMPMFSN CALL
020720,000492: 27,2152 44527 DELCOMP # COMPUTE THE ROTATION ABOUT SCAXIS TO
020721,000493: 27,2153 75160 AXC,1 AXC,2 # BRING MFS OUT OF GIMBAL LOCK
020722,000494: 27,2154 03246 MIS
020723,000495: 27,2155 02230 KEL
020724,000496: 27,2156 77624 CALL # COMPUTE THE NEW TRANSFORMATION FROM
020725,000497: 27,2157 44312 MXM3 # DESIRED S/C AXES TO STABLE MEMBER AXES
020726,000498: # WHICH WILL ALIGN VI WITH VF AND AVOID
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020728,000500: # GIMBAL LOCK
020729,000501: 27,2160 45160 FINDGIMB AXC,1 CALL
020730,000502: 27,2161 00000 0 # EXTRACT THE COMMANDED CDU ANGLES FROM
020731,000503: 27,2162 44654 DCMTOCDU # THIS MATRIX
020732,000504: 27,2163 40234 RTB SETPD
020733,000505: 27,2164 21621 V1STO2S # CONVERT TO 2:S COMPLEMENT
020734,000506: 27,2165 00001 0
020735,000507: 27,2166 77650 GOTO
020736,000508: 27,2167 03325 VECQTEMP # RETURN TO CALLER
020737,000509:
020738,000510: 27,2170 50375 PICKAXIS VLOAD DOT # IF VF X VI = 0, FIND VF . VI
020739,000511: 27,2171 00035 28D
020740,000512: 27,2172 03765 SCAXIS
020741,000513: 27,2173 72240 BMN TLOAD
020742,000514: 27,2174 54354 ROT180
020743,000515: 27,2175 00032 25D
020744,000516: 27,2176 77650 GOTO # IF VF = VI, CDU DESIRED = PRESENT CDU
020745,000517: 27,2177 03325 VECQTEMP # PRESENT CDU ANGLES
020746,000518:
020747,000519: 35,2000 BANK 35
020748,000520: 26,2000 SETLOC MANUVER1
020749,000521: 26,2000 BANK
020750,000522: 26,2354 47375 ROT180 VLOAD VXV # IF VF, VI ANTIPARALLEL, 108 DEG ROTATION
020751,000523: 26,2355 03255 MIS +6 # IS REQUIRED. Y STABLE MEMBER AXIS IN
020752,000524: 26,2356 06522 HIDPHALF # INITIAL S/C AXES.
020753,000525: 26,2357 47256 UNIT VXV # FIND Y(SM) X X(I)
020754,000526: 26,2360 03765 SCAXIS # FIND UNIT(VI X UNIT(Y(SM) X X(I)))
020755,000527: 26,2361 40056 UNIT BOV # I.E. PICK A VECTOR IN THE PLANE OF X(I),
020756,000528: 26,2362 54376 PICKX # Y(SM) PERPENDICULAR TO VI
020757,000529: 26,2363 17271 STODL COF
020758,000530: 26,2364 00045 36D # CHECK MAGNITUDE
020759,000531: 26,2365 50025 DSU BMN # OF THIS VECTOR.
020760,000532: 26,2366 14415 DPB-14 # IF LESS THAN B-14,
020761,000533: 26,2367 54376 PICKX # PICK X-AXIS.
020762,000534: 26,2370 77775 VLOAD
020763,000535: 26,2371 03271 COF
020764,000536: 26,2372 17271 XROT STODL COF
020765,000537: 26,2373 06522 HIDPHALF
020766,000538: 26,2374 77650 GOTO
020767,000539: 26,2375 56072 COMPMATX
020768,000540: 26,2376 52175 PICKX VLOAD GOTO # PICK THE XAXIS IN THIS CASE
020769,000541: 26,2377 06522 HIDPHALF
020770,000542: 26,2400 54372 XROT
020771,000543: 26,2401 15555 35172 SINGIMLC 2DEC .4285836003 # = SIN(59) $2
020772,000544:
020773,000545: 26,2403 14113 36326 SINVEC1 2DEC .3796356537 # = SIN(49.4) $2
020774,000546:
020775,000547: 26,2405 07701 35703 SINVEC2 2DEC .2462117800 # = SIN(29.5) $2
020776,000548:
020777,000549: 26,2407 04343 21616 VECANG1 2DEC .1388888889 # = 50 DEGREES $360
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Page 486 |
020779,000551: 26,2411 03070 34344 VECANG2 2DEC .09722222222 # = 35 DEGREES $360
020780,000552:
020781,000553: 26,2413 00000 1BITDP OCT 0 # KEEP THIS BEFORE DPB(-14) *********
020782,000554: 26,2414 00001 DPB-14 OCT 00001
020783,000555: 26,2415 00000 OCT 00000
020784,000556:
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Page 487 |
020786,000558: # ROUTINE FOR INITIATING AUTOMATIC MANEUVER VIA KEYBOARD (V49)
020787,000559:
020788,000560: 34,2000 BANK 34
020789,000561: 23,2000 SETLOC R62
020790,000562: 23,2000 BANK
020791,000563: 23,2103 E6,1676 EBANK= BCDU
020792,000564:
020793,000565: 23,2103 COUNT* $$/R62
020794,000566:
020795,000567: 23,2103 23,2103 R62DISP EQUALS R62FLASH
020796,000568:
020797,000569: 23,2103 35010 R62FLASH CAF V06N22 # FLASH V06N22 AND
020798,000570: 23,2104 04616 TC BANKCALL # ICDU ANGLES
020799,000571: 23,2105 20477 CADR GOFLASH
020800,000572: 23,2106 15472 TCF ENDEXT # TERMINATE
020801,000573: 23,2107 12111 TCF GOMOVE # PROCEED
020802,000574: 23,2110 12103 TCF R62FLASH # ENTER
020803,000575:
020804,000576: # ASTRONAUT MAY LOAD NEW ICDUS AT THIS
020805,000577: # POINT
020806,000578: 23,2111 05504 GOMOVE TC UPFLAG # SET FOR 3-AXIS MANEUVER
020807,000579: 23,2112 00124 ADRES 3AXISFLG
020808,000580:
020809,000581: 23,2113 04616 TC BANKCALL
020810,000582: 23,2114 54123 CADR R60LEM
020811,000583: 23,2115 15472 TCF ENDEXT # END R62
020812,000584:
End of include-file R60,R62.agc. Parent file is MAIN.agc