Source Code
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This is a reconstruction of the AGC program Luminary 99 Rev 0. It was the third release
of the Lunar Module flight software targeted for use in Apollo 11, after Luminary 96 and 97.
A bug (which had been around since at least Apollo 10, Luminary 69) was
discovered in Rev 0 shortly before the Apollo 11 flight, resulting in a last minute
revision into Rev 1,
which is what actually flew rather than
the Rev 0 presented here. A hardcopy of Rev 0 is known to
exist — it belonged to AGC developer Allan Klumpp for many years — but
unfortunately the Virtual AGC Project has not had access to that hardcopy. Thus
the code you see here had been reconstructed (we believe accurately) rather than
transcribed. The first step of the reconstruction of the Rev 0 source code was
the transcription of the Rev 1 source code from a hardcopy in the MIT Museum collection.
The process of reverting the active portion of the source code (i.e., other than
program comments) from Rev 1 to Rev 0 was very minor, consisting
only of moving the position of the STARTSB1 label in
FRESH START AND RESTART. Allan had previously given
us the checksums of the memory banks of Rev 0, and we have verified the program presented here has checksums
identical to all banks of Allan's listing of Rev 0. The notations on Allan's Rev 0 program listing read,
in part:GAP: ASSEMBLE REVISION 099 OF AGC PROGRAM LUMINARY BY NASA 2021112-051 A single program comment is known to differ between Rev 0 and Rev 1, but these are harder to reconstruct and verify than changes to the active portion of the code. Thus it is possible that there are additional differences between the program comments in Rev 0 and Rev 1 that are unknown to us, and therefore are not reflected in the code presented here. |
020701,000002: ## Copyright: Public domain.
020702,000003: ## Filename: R60,R62.agc
020703,000004: ## Purpose: Part of the reconstructed source code for LMY99 Rev 0,
020704,000005: ## otherwise known as Luminary Rev 99, the third release
020705,000006: ## of the Apollo Guidance Computer (AGC) software for Apollo 11.
020706,000007: ## It differs from LMY99 Rev 1 (the flown version) only in the
020707,000008: ## placement of a single label. The corrections shown here have
020708,000009: ## been verified to have the same bank checksums as AGC developer
020709,000010: ## Allan Klumpp's copy of Luminary Rev 99, and so are believed
020710,000011: ## to be accurate. This file is intended to be a faithful
020711,000012: ## recreation, except that the code format has been changed to
020712,000013: ## conform to the requirements of the yaYUL assembler rather than
020713,000014: ## the original YUL assembler.
020714,000015: ##
020715,000016: ## Assembler: yaYUL
020716,000017: ## Contact: Ron Burkey <info@sandroid.org>.
020717,000018: ## Website: www.ibiblio.org/apollo.
020718,000019: ## Pages: 472-485
020719,000020: ## Mod history: 2009-05-17 RSB Adapted from the corresponding
020720,000021: ## Luminary131 file, using page
020721,000022: ## images from Luminary 1A.
020722,000023: ## 2016-12-13 RSB GOTOP00H -> GOTOPOOH
020723,000024: ## 2016-12-14 RSB Proofed text comments with octopus/ProoferComments
020724,000025: ## and corrected the errors found.
020725,000026: ## 2017-01-27 RSB Back-ported a comment-text fix identified in Luminary 69.
020726,000027: ## 2017-03-09 RSB Comment text fixes noted in proofing Luminary 116.
020727,000028: ## 2017-08-01 MAS Created from LMY99 Rev 1.
020728,000029:
020729,000030: ## This source code has been transcribed or otherwise adapted from
020730,000031: ## digitized images of a hardcopy from the MIT Museum. The digitization
020731,000032: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
020732,000033: ## the Museum. Many thanks to both. The images (with suitable reduction
020733,000034: ## in storage size and consequent reduction in image quality as well) are
020734,000035: ## available online at www.ibiblio.org/apollo. If for some reason you
020735,000036: ## find that the images are illegible, contact me at info@sandroid.org
020736,000037: ## about getting access to the (much) higher-quality images which Paul
020737,000038: ## actually created.
020738,000039: ##
020739,000040: ## The code has been modified to match LMY99 Revision 0, otherwise
020740,000041: ## known as Luminary Revision 99, the Apollo 11 software release preceeding
020741,000042: ## the listing from which it was transcribed. It has been verified to
020742,000043: ## contain the same bank checksums as AGC developer Allan Klumpp's listing
020743,000044: ## of Luminary Revision 99 (for which we do not have scans).
020744,000045: ##
020745,000046: ## Notations on Allan Klumpp's listing read, in part:
020746,000047: ##
020747,000048: ## ASSEMBLE REVISION 099 OF AGC PROGRAM LUMINARY BY NASA 2021112-51
020748,000049:
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020750,000051: # MOD NO: 0 DATE: 1 MAY 1968
020751,000052: # MOD BY: DIGITAL DEVEL GROUP LOG SECTION R60,R62
020752,000053:
020753,000054: # FUNCTIONAL DESCRIPTION:
020754,000055:
020755,000056: # CALLED AS A GENERAL SUBROUTINE TO MANEUVER THE LM TO A SPECIFIED
020756,000057: # ATTITUDE.
020757,000058:
020758,000059: # 1. IF THE 3-AXIS FLAG IS NOT SET THE FINAL CDU ANGLES ARE
020759,000060: # CALCULATED (VECPOINT).
020760,000061:
020761,000062: # 2. THE FDAI BALL ANGLES (NOUN 18) ARE CALCULATED (BALLANGS).
020762,000063:
020763,000064: # 3. REQUEST FLASHING DISPLAY V50 N18 PLEASE PERFORM AUTO MANEUVER.
020764,000065:
020765,000066: # 4. IF PRIORITY DISPLAY FLAG IS SET DO A PHASECHANGE. THEN AWAIT
020766,000067: # ASTRONAUT RESPONSE.
020767,000068:
020768,000069: # 5. DISPLAY RESPONSE RETURNS:
020769,000070:
020770,000071: # A. ENTER - RESET 3-AXIS FLAG AND RETURN TO CLIENT.
020771,000072:
020772,000073: # B. TERMINATE - IF IN P00 GO TO STEP 5A. OTHERWISE CHECK IF R61 IS
020773,000074: # THE CALLING PROGRAM. IF IN R61 AN EXIT IS MADE TO GOTOV56. IF
020774,000075: # NOT IN R61 AN EXIT IS DONE VIA GOTOP00H.
020775,000076:
020776,000077: # C. PROCEED - CONTINUE WITH PROGRAM AT STEP 6.
020777,000078:
020778,000079: # 6. IF THE 3-AXISFLAG IS NOT SET, THE FINAL CDU ANGLES ARE CALCULATED
020779,000080: # (VECPOINT).
020780,000081:
020781,000082: # 7. THE FDAI BALL ANGLES (NOUN 18) ARE CALCULATED (BALLANGS).
020782,000083:
020783,000084: # 8. IF THE G+N SWITCH IS NOT SET GO BACK TO STEP 3.
020784,000085: #
020785,000086: # 9. IF THE AUTO SWITCH IS NOT SET GO BACK TO STEP 3.
020786,000087:
020787,000088: # 10. NONFLASHING DISPLAY V06N18 (FDAI ANGLES).
020788,000089:
020789,000090: # 11. DO A PHASECHANGE.
020790,000091:
020791,000092: # 12. DO A MANEUVER CALCULATION AND ICDU DRIVE ROUTINE TO ACHIEVE FINAL
020792,000093: # GIMBAL ANGLES (GOMANUR).
020793,000094:
020794,000095: # 13. AT END OF MANEUVER GO TO STEP 3.
020795,000096:
020796,000097: # IF SATISFACTORY MANEUVER STEP 5A EXITS R60.
020797,000098: # FOR FURTHER ADJUSTMENT OF THE VEHICLE ATTITUDE ABOUT THE
020798,000099: # DESIRED VECTOR, THE ROUTINE MAY BE PERFORMED AGAIN STARTING AT
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020800,000101: # STEP 5C.
020801,000102:
020802,000103: # CALLING SEQUENCE: TC BANKCALL
020803,000104: # CADR R60LEM
020804,000105:
020805,000106: # ERASABLE INITIALIZATION REQUIRED: SCAXIS, POINTVSM (FOR VECPOINT)
020806,000107: # 3AXISFLG.
020807,000108:
020808,000109: # SUBROUTINES CALLED: VECPOINT, BALLANGS, GOPERF2R, LINUS, GODSPER,
020809,000110: # GOMANUR, DOWNFLAG, PHASCHNG, UPFLAG
020810,000111:
020811,000112: # NORMAL EXIT MODES: CAE TEMPR60 (CALLERS RETURN ADDRESS)
020812,000113: # TC BANKJUMP
020813,000114:
020814,000115: # ALARMS: NONE
020815,000116:
020816,000117: # OUTPUT: NONE
020817,000118:
020818,000119: # DEBRIS: CPHI, CTHETA, CPSI, 3AXISFLG, TBASE2
020819,000120:
020820,000121: 34,2000 BANK 34
020821,000122: 26,2000 SETLOC MANUVER
020822,000123: 26,2000 BANK
020823,000124:
020824,000125: 26,2123 1164 EBANK= TEMPR60
020825,000126:
020826,000127: 26,2123 COUNT* $$/R06
020827,000128: 26,2123 04645 R60LEM TC MAKECADR
020828,000129: 26,2124 55164 TS TEMPR60
020829,000130:
020830,000131: 26,2125 34746 REDOMANN CAF 3AXISBIT
020831,000132: 26,2126 70101 MASK FLAGWRD5 # IS 3-AXIS FLAG SET
020832,000133: 26,2127 10000 CCS A
020833,000134: 26,2130 12136 TCF TOBALL # YES
020834,000135: 26,2131 06037 TC INTPRET
020835,000136: 26,2132 77624 CALL
020836,000137: 26,2133 56040 VECPOINT # TO COMPUTE FINAL ANGLES
020837,000138: 26,2134 00322 STORE CPHI # STORE FINAL ANGLES - CPHI, CTHETA, CPSI
020838,000139: 26,2135 77776 EXIT
020839,000140:
020840,000141: 26,2136 04616 TOBALL TC BANKCALL
020841,000142: 26,2137 54266 CADR BALLANGS # TO CONVERT ANGLES TO FDAI
020842,000143: 26,2140 32254 TOBALLA CAF V06N18
020843,000144: 26,2141 04616 TC BANKCALL
020844,000145: 26,2142 20710 CADR GOPERF2R # DISPLAY PLEASE PERFORM AUTO MANEUVER
020845,000146: 26,2143 02242 TC R61TEST
020846,000147: 26,2144 02150 TC REDOMANC # PROCEED
020847,000148: 26,2145 02175 TC ENDMANU1 # ENTER I.E. FINISHED WITH R60
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020849,000150: 26,2146 02201 TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
020850,000151: 26,2147 05155 TC ENDOFJOB
020851,000152:
020852,000153: 26,2150 34746 REDOMANC CAF 3AXISBIT
020853,000154: 26,2151 70101 MASK FLAGWRD5 # IS 3-AXIS FLAG SET
020854,000155: 26,2152 10000 CCS A
020855,000156: 26,2153 12161 TCF TOBALLC # YES
020856,000157: 26,2154 06037 TC INTPRET
020857,000158: 26,2155 77624 CALL
020858,000159: 26,2156 56040 VECPOINT # TO COMPUTE FINAL ANGLES
020859,000160: 26,2157 00322 STORE CPHI # STORE ANGLES
020860,000161: 26,2160 77776 EXIT
020861,000162:
020862,000163: 26,2161 04616 TOBALLC TC BANKCALL
020863,000164: 26,2162 54266 CADR BALLANGS # TO CONVERT ANGLES TO FDAI
020864,000165: 26,2163 02255 TC G+N,AUTO # CHECK AUTO MODE
020865,000166: 26,2164 10000 CCS A
020866,000167: 26,2165 12140 TCF TOBALLA # NOT AUTO, GO REREQUEST AUTO MANEUVER.
020867,000168:
020868,000169: 26,2166 32254 AUTOMANV CAF V06N18 # STATIC DISPLAY DURING AUTO MANEUVER
020869,000170: 26,2167 04616 TC BANKCALL # -
020870,000171: 26,2170 20451 CADR GODSPR # -
020871,000172: 26,2171 02201 TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
020872,000173:
020873,000174: 26,2172 04616 STARTMNV TC BANKCALL # PERFORM MANEUVER VIA KALCMANU
020874,000175: 26,2173 17750 CADR GOMANUR
020875,000176:
020876,000177: 26,2174 12140 ENDMANUV TCF TOBALLA # FINISHED MANEUVER.
020877,000178: 26,2175 05516 ENDMANU1 TC DOWNFLAG # RESET 3-AXIS FLAG
020878,000179: 26,2176 00124 ADRES 3AXISFLG
020879,000180: 26,2177 31164 CAE TEMPR60 # -
020880,000181: 26,2200 04640 TC BANKJUMP # -
020881,000182:
020882,000183: 26,2201 40100 CHKLINUS CS FLAGWRD4
020883,000184: 26,2202 74740 MASK PDSPFBIT # IS PRIORITY DISPLAY FLAG SET?
020884,000185: 26,2203 10000 CCS A # -
020885,000186: 26,2204 00002 TC Q # NO - EXIT
020886,000187: 26,2205 30002 CA Q
020887,000188: 26,2206 54156 TS MPAC +2 # SAVE RETURN
020888,000189: 26,2207 46245 CS THREE # OBTAIN LOCATION FOR RESTART
020889,000190: 26,2210 60133 AD BUF2 # HOLDS Q OF LAST DISPLAY
020890,000191: 26,2211 55055 TS TBASE2
020891,000192:
020892,000193: 26,2212 05353 TC PHASCHNG
020893,000194: 26,2213 00132 OCT 00132
020894,000195:
020895,000196: 26,2214 34745 CAF BIT7
020896,000197: 26,2215 05464 TC LINUS # GO SET BITS FOR PRIORITY DISPLAY -
020897,000198: 26,2216 00156 TC MPAC +2
020898,000199:
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020900,000201: 26,2217 37714 RELINUS CAF PRIO26 # RESTORE ORIGINAL PRIORITY
020901,000202: 26,2220 05146 TC PRIOCHNG
020902,000203:
020903,000204: 26,2221 34747 CAF TRACKBIT # DON'T CONTINUE R60 UNLESS TRACKFLAG ON.
020904,000205: 26,2222 70075 MASK FLAGWRD1
020905,000206: 26,2223 10000 CCS A
020906,000207: 26,2224 12237 TCF RER60
020907,000208:
020908,000209: 26,2225 34745 CAF RNDVZBIT # IS IT P20?
020909,000210: 26,2226 70074 MASK FLAGWRD0
020910,000211: 26,2227 10000 CCS A
020911,000212: 26,2230 02234 TC +4 # YES
020912,000213: 26,2231 05353 TC PHASCHNG # NO, MUST BE P25, SET 2.11 SPOT
020913,000214: 26,2232 40112 OCT 40112
020914,000215:
020915,000216: 26,2233 05155 TC ENDOFJOB
020916,000217:
020917,000218: 26,2234 05353 TC PHASCHNG # SET 2.7 SPOT FOR P20
020918,000219: 26,2235 40072 OCT 40072
020919,000220:
020920,000221: 26,2236 05155 TC ENDOFJOB
020921,000222:
020922,000223: 26,2237 05504 RER60 TC UPFLAG # SET PRIO DISPLAY FLAG AFTER RESTART
020923,000224: 26,2240 00077 ADRES PDSPFLAG
020924,000225:
020925,000226: 26,2241 01055 TC TBASE2
020926,000227:
020927,000228: 26,2242 31011 R61TEST CA MODREG # IF WE ARE IN P00 IT MUST BE V49 OR V89
020928,000229: 26,2243 00006 EXTEND
020929,000230: 26,2244 12175 BZF ENDMANU1 # THUS WE GO TO ENDEXT VIA USER
020930,000231:
020931,000232: 26,2245 30100 CA FLAGWRD4 # ARE WE IN R61 (P20 OR P25)
020932,000233: 26,2246 74740 MASK PDSPFBIT
020933,000234: 26,2247 00006 EXTEND
020934,000235: 26,2250 16001 BZF GOTOPOOH # NO
020935,000236: 26,2251 06022 TC GOTOV56 # YES
020936,000237:
020937,000238: 26,2252 20100 BIT14+7 OCT 20100 # -
020938,000239: 26,2253 00203 OCT203 OCT 203
020939,000240: 26,2254 01422 V06N18 VN 0618
020940,000241:
020941,000242: # SUBROUTINE TO CHECK FOR G+N CONTROL, AUTO STABILIZATION
020942,000243:
020943,000244: # RETURNS WITH C(A) = + IF NOT SET FOR G+N, AUTO
020944,000245: # RETURNS WITH C(A) = +0 IF SWITCHES ARE SET
020945,000246:
020946,000247: 26,2255 00006 G+N,AUTO EXTEND
020947,000248: 26,2256 00030 READ CHAN30
020948,000249: 26,2257 74742 MASK BIT10
020949,000250: 26,2260 10000 CCS A
020950,000251: 26,2261 00002 TC Q # NOT IN G+N C(A) = +
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020952,000253: 26,2262 00006 ISITAUTO EXTEND # CHECK FOR AUTO MODE
020953,000254: 26,2263 00031 READ CHAN31
020954,000255: 26,2264 74736 MASK BIT14
020955,000256: 26,2265 00002 TC Q # (+) = NOT IN AUTO, (+0) = AOK
020956,000257:
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020958,000259: # PROGRAM DESCRIPTION BALLANGS
020959,000260: # MOD NO. LOG SECTION R60,R62
020960,000261:
020961,000262: # WRITTEN BY RAMA M. AIYAWAR
020962,000263:
020963,000264: # FUNCTIONAL DESCRIPTION
020964,000265:
020965,000266: # COMPUTES LM FDAI BALL DISPLAY ANGLES
020966,000267:
020967,000268: # CALLING SEQUENCE
020968,000269:
020969,000270: # TC BALLANGS
020970,000271:
020971,000272: # NORMAL EXIT MODE
020972,000273:
020973,000274: # TC BALLEXIT (SAVED Q)
020974,000275:
020975,000276: # ALARM OR EXIT MODE NIL
020976,000277:
020977,000278: # SUBROUTINES CALLED
020978,000279:
020979,000280: # CD*TR*G
020980,000281: # ARCTAN
020981,000282:
020982,000283: # INPUT
020983,000284:
020984,000285: # CPHI,CTHETA,CPSI ARE THE ANGLES CORRESPONDING TO AOG, AIG, AMG. THEY ARE
020985,000286: # SP,2S COMPLIMENT SCALED TO HALF REVOLUTION.
020986,000287:
020987,000288: # OUTPUT
020988,000289:
020989,000290: # FDAIX, FDAIY, FDAIZ ARE THE REQUIRED BALL ANGLES SCALED TO HALF REVOLUTION
020990,000291: # SP,2S COMPLIMENT.
020991,000292:
020992,000293: # THESE ANGLES WILL BE DISPLAYED AS DEGREES AND HUNDREDTHS, IN THE ORDER ROLL, PITCH, YAW, USING NOUNS 18 & 19.
020993,000294:
020994,000295: # ERASABLE INITIALIZATION REQUIRED
020995,000296:
020996,000297: # CPHI, CTHETA, CPSI EACH A SP REGISTER
020997,000298:
020998,000299: # DEBRIS
020999,000300:
021000,000301: # A,L,Q,MPAC,SINCDU,COSCDU,PUSHLIST,BALLEXIT
021001,000302:
021002,000303: # NOMENCLATURE: CPHI, CTHETA, & CPSI REPRESENT THE OUTER, INNER, & MIDDLE GIMBAL ANGLES, RESPECTIVELY; OR
021003,000304: # EQUIVALENTLY, CDUX, CDUY, & CDUZ.
021004,000305:
021005,000306: # NOTE: ARCTAN CHECKS FOR OVERFLOW AND SHOULD BE ABLE TO HANDLE ANY SINGULARITIES.
021006,000307:
021007,000308: 26,2000 SETLOC BAWLANGS
021008,000309: 26,2000 BANK
021009,000310:
021010,000311: 26,2266 COUNT* $$/BALL
021011,000312: 26,2266 04645 BALLANGS TC MAKECADR
021012,000313: 26,2267 55342 TS BALLEXIT
021013,000314: 26,2270 30321 CA CPHI
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021015,000316: 26,2271 54772 TS CDUSPOT +4
021016,000317: 26,2272 30322 CA CTHETA
021017,000318: 26,2273 54766 TS CDUSPOT
021018,000319: 26,2274 30323 CA CPSI
021019,000320: 26,2275 54770 TS CDUSPOT +2
021020,000321:
021021,000322: 26,2276 06037 TC INTPRET
021022,000323: 26,2277 45001 SETPD CALL
021023,000324: 26,2300 00001 0D
021024,000325: 26,2301 47543 CD*TR*G
021025,000326:
021026,000327: 26,2302 41345 DLOAD DMP
021027,000328: 26,2303 00743 SINCDUX # SIN (OGA)
021028,000329: 26,2304 00747 COSCDUZ # COS (MGA)
021029,000330:
021030,000331: 26,2305 57552 SL1 DCOMP # SCALE
021031,000332: 26,2306 65336 ARCSIN PDDL # YAW = ARCSIN(-SXCZ) INTO 0 PD
021032,000333: 26,2307 00741 SINCDUZ
021033,000334: 26,2310 14023 STODL SINTH # (SINTH = 18D IN PD)
021034,000335: 26,2311 00747 COSCDUZ
021035,000336: 26,2312 72405 DMP SL1 # RESCALE
021036,000337: 26,2313 00751 COSCDUX
021037,000338: 26,2314 34021 STCALL COSTH # (COSTH = 16D IN PD)
021038,000339: 26,2315 26510 ARCTAN
021039,000340: 26,2316 41325 PDDL DMP # ROLL = ARCTAN(SZ/CZCX) INTO 2 PD
021040,000341: 26,2317 00741 SINCDUZ
021041,000342: 26,2320 00743 SINCDUX
021042,000343: 26,2321 41512 SL2 PUSH # SXSZ INTO 4 PD
021043,000344: 26,2322 65205 DMP PDDL # SXSZCY INTO 4 PD
021044,000345: 26,2323 00745 COSCDUY
021045,000346: 26,2324 65205 DMP PDDL # SXSZSY INTO 6 PD
021046,000347: 26,2325 00737 SINCDUY
021047,000348: 26,2326 00751 COSCDUX
021048,000349: 26,2327 72405 DMP SL1 # CXCY
021049,000350: 26,2330 00745 COSCDUY
021050,000351: 26,2331 45425 DSU STADR # PULL UP FROM 6 PD
021051,000352: 26,2332 63756 STODL COSTH # COSTH = CXCY - SXSZSY
021052,000353: 26,2333 00737 SINCDUY
021053,000354: 26,2334 72405 DMP SL1
021054,000355: 26,2335 00751 COSCDUX # CXSY
021055,000356: 26,2336 45415 DAD STADR # PULL UP FROM 4 PD
021056,000357: 26,2337 43754 STCALL SINTH # SINTH = CXSY + SXSZCY
021057,000358: 26,2340 26510 ARCTAN # RETURNS WITH D(MPAC) = PITCH
021058,000359: 26,2341 55525 PDDL VDEF # PITCH INTO 2 PD, ROLL INTO MPAC FROM 2 PD
021059,000360: 26,2342 77634 RTB # VDEF MAKES V(MPAC) = ROLL, PITCH, YAW
021060,000361: 26,2343 21620 V1STO2S
021061,000362: 26,2344 02345 STORE FDAIX # MODE IS TP
021062,000363: 26,2345 77776 EXIT
021063,000364:
021064,000365: 26,2346 31342 ENDBALL CA BALLEXIT
021065,000366:
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021067,000368: 26,2347 04640 TC BANKJUMP
021068,000369:
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021070,000371: # PROGRAM DESCRIPTION - VECPOINT
021071,000372:
021072,000373: # THIS INTERPRETIVE SUBROUTINE MAY BE USED TO POINT A SPACECRAFT AXIS IN A DESIRED DIRECTION. THE AXIS
021073,000374: # TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN SUCCESSIVE LOCATIONS OF ERASABLE MEMORY
021074,000375: # BEGINNING WITH THE LOCATION CALLED SCAXIS. THE COMPONENTS OF THIS VECTOR ARE GIVEN IN SPACECRAFT COORDINATES.
021075,000376: # THE DIRECTION IN WHICH THIS AXIS IS TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN
021076,000377: # SUCCESSIVE LOCATIONS OF ERASABLE MEMORY BEGINNING WITH THE ADDRESS CALLED POINTVSM. THE COMPONENTS OF THIS
021077,000378: # VECTOR ARE GIVEN IN STABLE MEMBER COORDINATES. WITH THIS INFORMATION VECPOINT COMPUTES A SET OF THREE GIMBAL
021078,000379: # ANGLES (2S COMPLEMENT) CORESPONDING TO THE CROSS-PRODUCT ROTATION BETWEEN SCAXIS AND POINTVSM AND STORES THEM
021079,000380: # IN T(MPAC) BEFORE RETURNING TO THE CALLER.
021080,000381:
021081,000382: # THIS ROTATION, HOWEVER, MAY BRING THE S/C INTO GIMBAL LOCK. WHEN POINTING A VECTOR IN THE Y-Z PLANE,
021082,000383: # THE TRANSPONDER AXIS, OR THE AOT FOR THE LEM, THE PROGRAM WILL CORRECT THIS PROBLEM BY ROTATING THE CROSS-
021083,000384: # PRODUCT ATTITUDE ABOUT POINTVSM BY A FIXED AMOUNT SUFFICIENT TO ROTATE THE DESIRED S/C ATTITUDE OUT OF GIMBAL
021084,000385: # 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,
021085,000386: # THE ADDITIONAL ROTATION TO AVOID GIMAL LOCK IS 35 DEGREES. IF THE AXIS IS MORE THAN 60.5 DEGEES FROM +X (OR -X)
021086,000387: # THE ADDITIONAL ROTATION IS 35 DEGREES. THE GIMBAL ANGLES CORRESPONDING TO THIS ATTITUDE ARE THEN COMPUTED AND
021087,000388: # STORED AS 2S COMPLIMENT ANGLES IN T(MPAC) BEFORE RETURNING TO THE CALLER.
021088,000389:
021089,000390: # WHEN POINTING THE X-AXIS, OR THE THRUST VECTOR, OR ANY VECTOR WITHIN 40.6 DEG OF THE X-AXIS, VECPOINT
021090,000391: # CANNOT CORRECT FOR A CROSS-PRODUCT ROTATION INTO GIMBAL LOCK. IN THIS CASE A PLATFORM REALIGNMENT WOULD BE
021091,000392: # REQUIRED TO POINT THE VECTOR IN THE DESIRED DIRECTION. AT PRESENT NO INDICATION IS GIVEN FOR THIS SITUATION
021092,000393: # EXCEPT THAT THE FINAL MIDDLE GIMBAL ANGLE IN MPAC +2 IS GREATER THAN 59 DEGREES.
021093,000394:
021094,000395: # CALLING SEQUENCE -
021095,000396:
021096,000397: # 1) LOAD SCAXIS, POINTVSM
021097,000398: # 2) CALL
021098,000399: # VECPOINT
021099,000400:
021100,000401: # RETURNS WITH
021101,000402:
021102,000403: # 1) DESIRED OUTER GIMBAL ANGLE IN MPAC
021103,000404: # 2) DESIRED INNER GIMBAL ANGLE IN MPAC +1
021104,000405: # 3) DESIRED MIDDLE GIMBAL ANGLE IN MPAC +2
021105,000406:
021106,000407: # ERASABLES USED -
021107,000408:
021108,000409: # 1) SCAXIS 6
021109,000410: # 2) POINTVSM 6
021110,000411: # 3) MIS 18
021111,000412: # 4) DEL 18
021112,000413: # 5) COF 6
021113,000414: # 6) VECQTEMP 1
021114,000415: # 7) ALL OF VAC AREA 43
021115,000416:
021116,000417: # TOTAL 99
021117,000418:
021118,000419: 27,2000 SETLOC VECPT
021119,000420: 27,2000 BANK
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021121,000422: 27,2032 COUNT* $$/VECPT
021122,000423:
021123,000424: 27,2032 E6,1676 EBANK= BCDU
021124,000425:
021125,000426: 27,2032 40020 VECPNT1 STQ BOV # THIS ENTRY USES DESIRED CDUS
021126,000427: 27,2033 03325 VECQTEMP # NOT PRESENT - ENTER WITH CDUD'S IN MPAC
021127,000428: 27,2034 56035 VECPNT2
021128,000429: 27,2035 52164 VECPNT2 AXC,2 GOTO
021129,000430: 27,2036 03246 MIS
021130,000431: 27,2037 56046 STORANG
021131,000432: 27,2040 40020 VECPOINT STQ BOV # SAVE RETURN ADDRESS
021132,000433: 27,2041 03325 VECQTEMP
021133,000434: 27,2042 56043 VECLEAR # AND CLEAR OVFIND
021134,000435: 27,2043 47164 VECLEAR AXC,2 RTB
021135,000436: 27,2044 03246 MIS # READ THE PRESENT CDU ANGLES AND
021136,000437: 27,2045 44403 READCDUK # STORE THEM IN PD25, 26, 27
021137,000438: 27,2046 34032 STORANG STCALL 25D
021138,000439: 27,2047 44410 CDUTODCM # S/C AXES TO STABLE MEMBER AXES (MIS)
021139,000440: 27,2050 61375 VLOAD VXM
021140,000441: 27,2051 03773 POINTVSM # RESOLVE THE POINTING DIRECTION VF INTO
021141,000442: 27,2052 03247 MIS # INITIAL S/C AXES (VF = POINTVSM)
021142,000443: 27,2053 77656 UNIT
021143,000444: 27,2054 00035 STORE 28D
021144,000445: # PD 28 29 30 31 32 33
021145,000446: 27,2055 53435 VXV UNIT # TAKE THE CROSS PRODUCT VF X VI
021146,000447: 27,2056 03765 SCAXIS # WHERE VI = SCAXIS
021147,000448: 27,2057 57400 BOV VCOMP
021148,000449: 27,2060 56170 PICKAXIS
021149,000450: 27,2061 17271 STODL COF # CHECK MAGNITUDE
021150,000451: 27,2062 00045 36D # OF CROSS PRODUCT
021151,000452: 27,2063 50025 DSU BMN # VECTOR, IF LESS
021152,000453: 27,2064 14411 DPB-14 # THAN B-14 ASSUME
021153,000454: 27,2065 56170 PICKAXIS # UNIT OPERATION
021154,000455: 27,2066 50375 VLOAD DOT # INVALID.
021155,000456: 27,2067 03765 SCAXIS
021156,000457: 27,2070 00035 28D
021157,000458: 27,2071 65552 SL1 ARCCOS
021158,000459: 27,2072 77624 COMPMATX CALL # NOW COMPUTE THE TRANSFORMATION FROM
021159,000460: 27,2073 44527 DELCOMP # FINAL S/C AXES TO INITIAL S/C AXES MFI
021160,000461: 27,2074 75160 AXC,1 AXC,2
021161,000462: 27,2075 03246 MIS # COMPUTE THE TRANSFORMATION FROM FINAL
021162,000463: 27,2076 02230 KEL # S/C AXES TO STABLE MEMBER AXES
021163,000464: 27,2077 77624 CALL # MFS = MIS MFI
021164,000465: 27,2100 44312 MXM3 # (IN PD LIST)
021165,000466:
021166,000467: 27,2101 51545 DLOAD ABS
021167,000468: 27,2102 00007 6 # MFS6 = SIN(CPSI) $2
021168,000469: 27,2103 50025 DSU BMN
021169,000470: 27,2104 14376 SINGIMLC # = SIN(59 DEGS) $2
021170,000471: 27,2105 56160 FINDGIMB # /CPSI/ LESS THAN 59 DEGS
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021172,000473: # I.E. DESIRED ATTITUDE NOT IN GIMBAL LOCK
021173,000474:
021174,000475: 27,2106 51545 DLOAD ABS # CHECK TO SEE IF WE ARE POINTING
021175,000476: 27,2107 03765 SCAXIS # THE THRUST AXIS
021176,000477: 27,2110 51025 DSU BPL
021177,000478: 27,2111 14400 SINVEC1 # SIN 49.4 DEGS $2
021178,000479: 27,2112 56160 FINDGIMB # IF SO, WE ARE TRYING TO POINT IT INTO
021179,000480: 27,2113 77775 VLOAD # GIMBAL LOCK, ABORT COULD GO HERE
021180,000481: 27,2114 77626 STADR
021181,000482: 27,2115 50514 STOVL MIS +12D
021182,000483: 27,2116 77626 STADR # STORE MFS (IN PD LIST) IN MIS
021183,000484: 27,2117 50522 STOVL MIS +6
021184,000485: 27,2120 77626 STADR
021185,000486: 27,2121 50530 STOVL MIS
021186,000487: 27,2122 03255 MIS +6 # INNER GIMBAL AXIS IN FINAL S/C AXES
021187,000488: 27,2123 57444 BPL VCOMP # LOCATE THE IG AXIS DIRECTION CLOSEST TO
021188,000489: 27,2124 56125 IGSAMEX # FINAL X S/C AXIS
021189,000490:
021190,000491: 27,2125 50035 IGSAMEX VXV BMN # FIND THE SHORTEST WAY OF ROTATING THE
021191,000492: 27,2126 03765 SCAXIS # S/C OUT OF GIMBAL LOCK BY A ROTATION
021192,000493: 27,2127 56134 U=SCAXIS # ABOUT +- SCAXIS, I.E. IF (IG (SGN MFS3)
021193,000494: # X SCAXIS . XF) LESS THAN 0, U = SCAXIS
021194,000495: # OTHERWISE U = -SCAXIS
021195,000496:
021196,000497: 27,2130 57575 VLOAD VCOMP
021197,000498: 27,2131 03765 SCAXIS
021198,000499: 27,2132 37271 STCALL COF # ROTATE ABOUT -SCAXIS
021199,000500: 27,2133 56137 CHEKAXIS
021200,000501: 27,2134 77775 U=SCAXIS VLOAD
021201,000502: 27,2135 03765 SCAXIS
021202,000503: 27,2136 03271 STORE COF # ROTATE ABOUT + SCAXIS
021203,000504: 27,2137 51545 CHEKAXIS DLOAD ABS
021204,000505: 27,2140 03765 SCAXIS # SEE IF WE ARE POINTING THE AOT
021205,000506: 27,2141 51025 DSU BPL
021206,000507: 27,2142 14402 SINVEC2 # SIN 29.5 DEGS $2
021207,000508: 27,2143 56147 PICKANG1 # IF SO, ROTATE 50 DEGS ABOUT +- SCAXIS
021208,000509: 27,2144 52145 DLOAD GOTO # IF NOT, MUST BE POINTING THE TRANSPONDER
021209,000510: 27,2145 14406 VECANG2 # OR SOME VECTOR IN THE Y, OR Z PLANE
021210,000511: 27,2146 56151 COMPMFSN # IN THIS CASE ROTATE 35 DEGS TO GET OUT
021211,000512: # OF GIMBAL LOCK (VECANG2 $360)
021212,000513: 27,2147 77745 PICKANG1 DLOAD
021213,000514: 27,2150 14404 VECANG1 # = 50 DEGS $360
021214,000515: 27,2151 77624 COMPMFSN CALL
021215,000516: 27,2152 44527 DELCOMP # COMPUTE THE ROTATION ABOUT SCAXIS TO
021216,000517: 27,2153 75160 AXC,1 AXC,2 # BRING MFS OUT OF GIMBAL LOCK
021217,000518: 27,2154 03246 MIS
021218,000519: 27,2155 02230 KEL
021219,000520: 27,2156 77624 CALL # COMPUTE THE NEW TRANSFORMATION FROM
021220,000521: 27,2157 44312 MXM3 # DESIRED S/C AXES TO STABLE MEMBER AXES
021221,000522: # WHICH WILL ALIGN VI WITH VF AND AVOID
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021223,000524: # GIMBAL LOCK
021224,000525: 27,2160 45160 FINDGIMB AXC,1 CALL
021225,000526: 27,2161 00000 0 # EXTRACT THE COMMANDED CDU ANGLES FROM
021226,000527: 27,2162 44654 DCMTOCDU # THIS MATRIX
021227,000528: 27,2163 40234 RTB SETPD
021228,000529: 27,2164 21620 V1STO2S # CONVERT TO 2:S COMPLEMENT
021229,000530: 27,2165 00001 0
021230,000531: 27,2166 77650 GOTO
021231,000532: 27,2167 03325 VECQTEMP # RETURN TO CALLER
021232,000533:
021233,000534: 27,2170 50375 PICKAXIS VLOAD DOT # IF VF X VI = 0, FIND VF . VI
021234,000535: 27,2171 00035 28D
021235,000536: 27,2172 03765 SCAXIS
021236,000537: 27,2173 72240 BMN TLOAD
021237,000538: 27,2174 54350 ROT180
021238,000539: 27,2175 00032 25D
021239,000540: 27,2176 77650 GOTO # IF VF = VI, CDU DESIRED = PRESENT CDU
021240,000541: 27,2177 03325 VECQTEMP # PRESENT CDU ANGLES
021241,000542:
021242,000543: 35,2000 BANK 35
021243,000544: 26,2000 SETLOC MANUVER1
021244,000545: 26,2000 BANK
021245,000546: 26,2350 47375 ROT180 VLOAD VXV # IF VF, VI ANTIPARALLEL, 108 DEG ROTATION
021246,000547: 26,2351 03255 MIS +6 # IS REQUIRED. Y STABLE MEMBER AXIS IN
021247,000548: 26,2352 06520 HIDPHALF # INITIAL S/C AXES.
021248,000549: 26,2353 47256 UNIT VXV # FIND Y(SM) X X(I)
021249,000550: 26,2354 03765 SCAXIS # FIND UNIT(VI X UNIT(Y(SM) X X(I)))
021250,000551: 26,2355 40056 UNIT BOV # I.E. PICK A VECTOR IN THE PLANE OF X(I),
021251,000552: 26,2356 54372 PICKX # Y(SM) PERPENDICULAR TO VI
021252,000553: 26,2357 17271 STODL COF
021253,000554: 26,2360 00045 36D # CHECK MAGNITUDE
021254,000555: 26,2361 50025 DSU BMN # OF THIS VECTOR.
021255,000556: 26,2362 14411 DPB-14 # IF LESS THAN B-14,
021256,000557: 26,2363 54372 PICKX # PICK X-AXIS.
021257,000558: 26,2364 77775 VLOAD
021258,000559: 26,2365 03271 COF
021259,000560: 26,2366 17271 XROT STODL COF
021260,000561: 26,2367 06520 HIDPHALF
021261,000562: 26,2370 77650 GOTO
021262,000563: 26,2371 56072 COMPMATX
021263,000564: 26,2372 52175 PICKX VLOAD GOTO # PICK THE XAXIS IN THIS CASE
021264,000565: 26,2373 06520 HIDPHALF
021265,000566: 26,2374 54366 XROT
021266,000567: 26,2375 15555 35172 SINGIMLC 2DEC .4285836003 # = SIN(59) $2
021267,000568:
021268,000569: 26,2377 14113 36326 SINVEC1 2DEC .3796356537 # = SIN(49.4) $2
021269,000570:
021270,000571: 26,2401 07701 35703 SINVEC2 2DEC .2462117800 # = SIN(29.5) $2
021271,000572:
021272,000573: 26,2403 04343 21616 VECANG1 2DEC .1388888889 # = 50 DEGREES $360
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021274,000575: 26,2405 03070 34344 VECANG2 2DEC .09722222222 # = 35 DEGREES $360
021275,000576:
021276,000577: 26,2407 00000 1BITDP OCT 0 # KEEP THIS BEFORE DPB(-14) *********
021277,000578: 26,2410 00001 DPB-14 OCT 00001
021278,000579: 26,2411 00000 OCT 00000
021279,000580:
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021281,000582: # ROUTINE FOR INITIATING AUTOMATIC MANEUVER VIA KEYBOARD (V49)
021282,000583:
021283,000584: 34,2000 BANK 34
021284,000585: 23,2000 SETLOC R62
021285,000586: 23,2000 BANK
021286,000587: 23,2103 E6,1676 EBANK= BCDU
021287,000588:
021288,000589: 23,2103 COUNT* $$/R62
021289,000590:
021290,000591: 23,2103 23,2103 R62DISP EQUALS R62FLASH
021291,000592:
021292,000593: 23,2103 35010 R62FLASH CAF V06N22 # FLASH V06N22 AND
021293,000594: 23,2104 04616 TC BANKCALL # ICDU ANGLES
021294,000595: 23,2105 20476 CADR GOFLASH
021295,000596: 23,2106 15472 TCF ENDEXT # TERMINATE
021296,000597: 23,2107 12111 TCF GOMOVE # PROCEED
021297,000598: 23,2110 12103 TCF R62FLASH # ENTER
021298,000599:
021299,000600: # ASTRONAUT MAY LOAD NEW ICDUS AT THIS
021300,000601: # POINT
021301,000602: 23,2111 05504 GOMOVE TC UPFLAG # SET FOR 3-AXIS MANEUVER
021302,000603: 23,2112 00124 ADRES 3AXISFLG
021303,000604:
021304,000605: 23,2113 04616 TC BANKCALL
021305,000606: 23,2114 54123 CADR R60LEM
021306,000607: 23,2115 15472 TCF ENDEXT # END R62
021307,000608:
End of include-file R60,R62.agc. Parent file is MAIN.agc