Source Code

058713,000001: # Copyright: Public domain. 058714,000002: # Filename: INFLIGHT_ALIGNMENT_ROUTINES.agc 058715,000003: # Purpose: Part of the source code for Colossus 2A, AKA Comanche 055. 058716,000004: # It is part of the source code for the Command Module's (CM) 058717,000005: # Apollo Guidance Computer (AGC), for Apollo 11. 058718,000006: # Assembler: yaYUL 058719,000007: # Contact: Ron Burkey <info@sandroid.org>. 058720,000008: # Website: www.ibiblio.org/apollo. 058721,000009: # Pages: 1355-1364 058722,000010: # Mod history: 2009-05-14 RSB Adapted from the Colossus249/ file of the 058723,000011: # same name, using Comanche055 page images. 058724,000012: 058725,000013: # This source code has been transcribed or otherwise adapted from digitized 058726,000014: # images of a hardcopy from the MIT Museum. The digitization was performed 058727,000015: # by Paul Fjeld, and arranged for by Deborah Douglas of the Museum. Many 058728,000016: # thanks to both. The images (with suitable reduction in storage size and 058729,000017: # consequent reduction in image quality as well) are available online at 058730,000018: # www.ibiblio.org/apollo. If for some reason you find that the images are 058731,000019: # illegible, contact me at info@sandroid.org about getting access to the 058732,000020: # (much) higher-quality images which Paul actually created. 058733,000021: 058734,000022: # Notations on the hardcopy document read, in part: 058735,000023: 058736,000024: # Assemble revision 055 of AGC program Comanche by NASA 058737,000025: # 2021113-051. 10:28 APR. 1, 1969 058738,000026: 058739,000027: # This AGC program shall also be referred to as 058740,000028: # Colossus 2A 058741,000029: 058742,000030: # Page 1355 058743,000031: 22,3510 BANK 22 058744,000032: 23,2000 SETLOC INFLIGHT 058745,000033: 23,2000 BANK 058746,000034: 058747,000035: 23,3205 E5,1671 EBANK= XSM 058748,000036: 058749,000037: # CALCGTA COMPUTES THE GYRO TORQUE ANGLES REQUIRED TO BRING THE STABLE MEMBER INTO THE DESIRED ORIENTATION. 058750,000038: 058751,000039: # THE INPUT IS THE DESIRED STABLE MEMBER COORDINATES REFERRED TO PRESENT STABLE MEMBER COORDINATES. THE THREE 058752,000040: # HALF-UNIT VECTORS ARE STORED AT XDC, YDC, AND ZDC. 058753,000041: 058754,000042: # THE OUTPUTS ARE THE THREE GYRO TORQUE ANGLES TO BE APPLIED TO THE Y, Z, AND X GYROS AND ARE STORED DP AT IGC, 058755,000043: # MGC, AND OGC RESPECTIVELY. 058756,000044: 058757,000045: 23,3205 COUNT 23/INFLT 058758,000046: 058759,000047: 23,3205 71220 CALCGTA ITA DLOAD # PUSHDOWN 00-03, 16D-27D, 34D-37D 058760,000048: 23,3206 00051 S2 # XDC = (XD1 XD2 XD3) 058761,000049: 23,3207 02714 XDC # YDC = (YD1 YD2 YD3) 058762,000050: 23,3210 65325 PDDL PDDL # ZDC = (ZD1 ZD2 ZD3) 058763,000051: 23,3211 15335 HI6ZEROS 058764,000052: 23,3212 02720 XDC +4 058765,000053: 23,3213 55476 DCOMP VDEF 058766,000054: 23,3214 77656 UNIT 058767,000055: 23,3215 14027 STODL ZPRIME # ZP = UNIT(-XD3 0 XD1) = (ZP1 ZP2 ZP3) 058768,000056: 23,3216 00027 ZPRIME 058769,000057: 058770,000058: 23,3217 77742 SR1 058771,000059: 23,3220 14023 STODL SINTH # SIN(IGC) = ZP1 058772,000060: 23,3221 00033 ZPRIME +4 058773,000061: 23,3222 77742 SR1 058774,000062: 23,3223 34021 STCALL COSTH # COS(IGC) = ZP3 058775,000063: 23,3224 47256 ARCTRIG 058776,000064: 058777,000065: 23,3225 16762 STODL IGC # Y GYRO TORQUING ANGLE FRACTION OF REV. 058778,000066: 23,3226 02716 XDC +2 058779,000067: 23,3227 77742 SR1 058780,000068: 23,3230 14023 STODL SINTH # SIN(MGC) = XD2 058781,000069: 23,3231 00027 ZPRIME 058782,000070: 058783,000071: 23,3232 65205 DMP PDDL 058784,000072: 23,3233 02720 XDC +4 # PD00 = (ZP1)(XD3) 058785,000073: 23,3234 00033 ZPRIME +4 058786,000074: 058787,000075: 23,3235 45205 DMP DSU 058788,000076: 23,3236 02714 XDC # MPAC = (ZP3)(XD1) 058789,000077: 23,3237 77626 STADR 058790,000078: 23,3240 43756 STCALL COSTH # COS(MGC) = MPAC - PD00 058791,000079: 23,3241 47256 ARCTRIG 058792,000080: # Page 1356 058793,000081: 23,3242 26764 STOVL MGC # Z GYRO TORQUING ANGLE FRACTION OF REV. 058794,000082: 23,3243 00027 ZPRIME 058795,000083: 23,3244 77641 DOT 058796,000084: 23,3245 02730 ZDC 058797,000085: 23,3246 24021 STOVL COSTH # COS(OGC) = ZP . ZDC 058798,000086: 23,3247 00027 ZPRIME 058799,000087: 23,3250 77641 DOT 058800,000088: 23,3251 02722 YDC 058801,000089: 23,3252 34023 STCALL SINTH # SIN(OGC) = ZP . YDC 058802,000090: 23,3253 47256 ARCTRIG 058803,000091: 058804,000092: 23,3254 36760 STCALL OGC # X GYRO TORQUING ANGLE FRACTION OF REV. 058805,000093: 23,3255 00051 S2 058806,000094: 058807,000095: # Page 1357 058808,000096: # ARCTRIG COMPUTES AN ANGLE GIVEN THE SINE AND COSINE OF THIS ANGLE. 058809,000097: 058810,000098: # THE INPUTS ARE SIN/4 AND COS/4 STORED DP AT SINTH AND COSTH. 058811,000099: 058812,000100: # THE OUTPUT IS THE CALCULATED ANGLE BETWEEN +.5 AND -.5 REVOLUTIONS AND STORED AT THETA. THE OUTPUT IS ALSO 058813,000101: # AVAILABLE AT MPAC. 058814,000102: 058815,000103: 23,3256 51545 ARCTRIG DLOAD ABS # PUSHDOWN 16D-21D 058816,000104: 23,3257 00023 SINTH 058817,000105: 23,3260 50025 DSU BMN 058818,000106: 23,3261 07474 QTSN45 # ABS(SIN/4) - SIN(45)/4 058819,000107: 23,3262 47271 TRIG1 # IF (-45,45) OR (135,-135) 058820,000108: 058821,000109: 23,3263 72545 DLOAD SL1 # (45,135) OR (-135,-45) 058822,000110: 23,3264 00021 COSTH 058823,000111: 23,3265 75326 ACOS SIGN 058824,000112: 23,3266 00023 SINTH 058825,000113: 23,3267 00025 STORE THETA # X = ARCCOS(COS) WITH SIGN(SIN) 058826,000114: 23,3270 77616 RVQ 058827,000115: 058828,000116: 23,3271 72545 TRIG1 DLOAD SL1 # (-45,45) OR (135,-135) 058829,000117: 23,3272 00023 SINTH 058830,000118: 23,3273 77736 ASIN 058831,000119: 23,3274 14025 STODL THETA # X = ARCSIN(SIN) WITH SIGN(SIN) 058832,000120: 23,3275 00021 COSTH 058833,000121: 23,3276 77640 BMN 058834,000122: 23,3277 47302 TRIG2 # IF (135,-135) 058835,000123: 058836,000124: 23,3300 43545 DLOAD RVQ 058837,000125: 23,3301 00025 THETA # X = ARCSIN(SIN) (-45,45) 058838,000126: 058839,000127: 23,3302 75345 TRIG2 DLOAD SIGN # (135,-135) 058840,000128: 23,3303 15333 HIDPHALF 058841,000129: 23,3304 00023 SINTH 058842,000130: 23,3305 77625 DSU 058843,000131: 23,3306 00025 THETA 058844,000132: 23,3307 00025 STORE THETA # X = .5 WITH SIGN(SIN) - ARCSIN(SIN) 058845,000133: 23,3310 77616 RVQ # (+) - (+) OR (-) - (-) 058846,000134: 058847,000135: # Page 1358 058848,000136: # SMNB, NBSM, AND AXISROT, WHICH USED TO APPEAR HERE, HAVE BEEN 058849,000137: # COMBINED IN A ROUTINE CALLED AX*SR*T, WHICH APPEARS AMONG THE POWERED 058850,000138: # FLIGHT SUBROUTINES. 058851,000139: 058852,000140: # Page 1359 058853,000141: # CALCGA COMPUTES THE CDU DRIVING ANGLES REQUIRED TO BRING THE STABLE MEMBER INTO THE DESIRED ORIENTATION. 058854,000142: 058855,000143: # THE INPUTS ARE 1) THE NAVIGATION BASE COORDINATES REFERRED TO ANY COORDINATE SYSTEM. THE THREE HALF-UNIT 058856,000144: # VECTORS ARE STORED AT XNB, YNB, AND ZNB. 2) THE DESIRED STABLE MEMBER COORDINATES REFERRED TO THE SAME 058857,000145: # COORDINATE SYSTEM ARE STORED AT XSM, YSM, AND ZSM. 058858,000146: 058859,000147: # THE OUTPUTS ARE THE THREE CDU DRIVING ANGLES AND ARE STORED SP AT THETAD, THETAD +1, AND THETAD +2. 058860,000148: 058861,000149: 23,3311 77601 CALCGA SETPD # PUSHDOWN 00-05, 16D-21D, 34D-37D 058862,000150: 23,3312 00001 0 058863,000151: 23,3313 47375 VLOAD VXV 058864,000152: 23,3314 02714 XNB # XNB = OGA (OUTER GIMBAL AXIS) 058865,000153: 23,3315 02700 YSM # YSM = IGA (INNER GIMBAL AXIS) 058866,000154: 23,3316 41456 UNIT PUSH # PD0 = UNIT(OGA X IGA) = MGA 058867,000155: 058868,000156: 23,3317 44041 DOT ITA 058869,000157: 23,3320 02730 ZNB 058870,000158: 23,3321 00051 S2 058871,000159: 23,3322 24021 STOVL COSTH # COS(OG) = MGA . ZNB 058872,000160: 23,3323 00001 0 058873,000161: 23,3324 77641 DOT 058874,000162: 23,3325 02722 YNB 058875,000163: 23,3326 34023 STCALL SINTH # SIN(OG) = MGA . YNB 058876,000164: 23,3327 47256 ARCTRIG 058877,000165: 23,3330 26760 STOVL OGC 058878,000166: 23,3331 00001 0 058879,000167: 058880,000168: 23,3332 50235 VXV DOT # PROVISION FOR MG ANGLE OF 90 DEGREES 058881,000169: 23,3333 02714 XNB 058882,000170: 23,3334 02700 YSM 058883,000171: 23,3335 77752 SL1 058884,000172: 23,3336 24021 STOVL COSTH # COS(MG) = IGA . (MGA X OGA) 058885,000173: 23,3337 02700 YSM 058886,000174: 23,3340 77641 DOT 058887,000175: 23,3341 02714 XNB 058888,000176: 23,3342 34023 STCALL SINTH # SIN(MG) = IGA . OGA 058889,000177: 23,3343 47256 ARCTRIG 058890,000178: 23,3344 02764 STORE MGC 058891,000179: 058892,000180: 23,3345 45246 ABS DSU 058893,000181: 23,3346 07476 .166... 058894,000182: 23,3347 77644 BPL 058895,000183: 23,3350 47371 GIMLOCK1 # IF ANGLE GREATER THAN 60 DEGREES 058896,000184: 058897,000185: 23,3351 50375 CALCGA1 VLOAD DOT 058898,000186: 23,3352 02706 ZSM 058899,000187: 23,3353 00001 0 058900,000188: 23,3354 24021 STOVL COSTH # COS(IG) = ZSM . MGA 058901,000189: 23,3355 02672 XSM 058902,000190: # Page 1360 058903,000191: 23,3356 45441 DOT STADR 058904,000192: 23,3357 43754 STCALL SINTH # SIN(IG) = XSM . MGA 058905,000193: 23,3360 47256 ARCTRIG 058906,000194: 058907,000195: 23,3361 26762 STOVL IGC 058908,000196: 23,3362 02760 OGC 058909,000197: 23,3363 43034 RTB BONCLR 058910,000198: 23,3364 45552 V1STO2S 058911,000199: 23,3365 00200 CPHIFLAG 058912,000200: 23,3366 00051 S2 058913,000201: 23,3367 35156 STCALL THETAD 058914,000202: 23,3370 00051 S2 058915,000203: 058916,000204: 23,3371 77776 GIMLOCK1 EXIT 058917,000205: 23,3372 05650 TC ALARM 058918,000206: 23,3373 00401 OCT 00401 058919,000207: 23,3374 05546 TC UPFLAG # GIMBAL LOCK HAS OCCURRED 058920,000208: 23,3375 00056 ADRES GLOKFAIL 058921,000209: 058922,000210: 23,3376 06006 TC INTPRET 058923,000211: 23,3377 77650 GOTO 058924,000212: 23,3400 47351 CALCGA1 058925,000213: 058926,000214: # Page 1361 058927,000215: # AXISGEN COMPUTES THE COORDINATES OF ONE COORDINATE SYSTEM REFERRED TO ANOTHER COORDINATE SYSTEM. 058928,000216: 058929,000217: # THE INPUTS ARE 1) THE STAR1 VECTOR REFERRED TO COORDINATE SYSTEM A STORED AT STARAD. 2) THE STAR2 VECTOR 058930,000218: # REFERRED TO COORDINATE SYSTEM A STORED AT STARAD +6. 3) THE STAR1 VECTOR REFERRED TO COORDINATE SYSTEM B STORED 058931,000219: # AT LOCATION 6 OF THE VAC AREA. 4) THE STAR2 VECTOR REFERRED TO COORDINATE SYSTEM B STORED AT LOCATION 12D OF 058932,000220: # THE VAC AREA. 058933,000221: 058934,000222: # THE OUTPUT DEFINES COORDINATE SYSTEM A REFERRED TO COORDINATE SYSTEM B. THE THREE HALF-UNIT VECTORS ARE STORED 058935,000223: # AT LOCATIONS XDC, XDC +6, XDC +12D, AND STARAD, STARAD +6, STARAD +12D. 058936,000224: 058937,000225: 23,3401 66370 AXISGEN AXT,1 SSP # PUSHDOWN 00-30D, 34D-37D 058938,000226: 23,3402 02743 STARAD +6 058939,000227: 23,3403 00051 S1 058940,000228: 23,3404 02727 STARAD -6 058941,000229: 058942,000230: 23,3405 77601 SETPD 058943,000231: 23,3406 00001 0 058944,000232: 23,3407 46773 AXISGEN1 VLOAD* VXV* # 06D UA = S1 058945,000233: 23,3410 02752 STARAD +12D,1 # STARAD +00D UB = S1 058946,000234: 23,3411 02760 STARAD +18D,1 058947,000235: 23,3412 77656 UNIT # 12D VA = UNIT(S1 X S2) 058948,000236: 23,3413 06760 STORE STARAD +18D,1 # STARAD +06D VB = UNIT(S1 X S2) 058949,000237: 23,3414 77773 VLOAD* 058950,000238: 23,3415 02752 STARAD +12D,1 058951,000239: 058952,000240: 23,3416 76433 VXV* VSL1 058953,000241: 23,3417 02760 STARAD +18D,1 # 18D WA = UA X VA 058954,000242: 23,3420 06766 STORE STARAD +24D,1 # STARAD +12D WB = UB X VB 058955,000243: 058956,000244: 23,3421 77700 TIX,1 058957,000245: 23,3422 47407 AXISGEN1 058958,000246: 058959,000247: 23,3423 66160 AXC,1 SXA,1 058960,000248: 23,3424 00006 6 058961,000249: 23,3425 00036 30D 058962,000250: 058963,000251: 23,3426 66370 AXT,1 SSP 058964,000252: 23,3427 00022 18D 058965,000253: 23,3430 00051 S1 058966,000254: 23,3431 00006 6 058967,000255: 058968,000256: 23,3432 66374 AXT,2 SSP 058969,000257: 23,3433 00006 6 058970,000258: 23,3434 00052 S2 058971,000259: 23,3435 00002 2 058972,000260: 058973,000261: 23,3436 76720 AXISGEN2 XCHX,1 VLOAD* 058974,000262: 23,3437 00036 30D # X1=-6 X2=+6 X1=-6 X2=+4 X1=-6 X2=+2 058975,000263: 23,3440 00001 0,1 058976,000264: 058977,000265: # Page 1362 058978,000266: 23,3441 62757 VXSC* PDVL* # J=(UA)(UB1) J=(UA)(UB2) J=(UA)(UB3) 058979,000267: 23,3442 75033 STARAD +6,2 058980,000268: 23,3443 00007 6,1 058981,000269: 23,3444 77757 VXSC* 058982,000270: 23,3445 75025 STARAD +12D,2 058983,000271: 23,3446 30031 STOVL* 24D # K=(VA)(VB1) J=(VA)(VB2) J=(VA)(VB3) 058984,000272: 23,3447 00015 12D,1 058985,000273: 058986,000274: 23,3450 53357 VXSC* VAD 058987,000275: 23,3451 75017 STARAD +18D,2 # L=(WA)(WB1) J=(WA)(WB2) J=(WA)(WB3) 058988,000276: 23,3452 76455 VAD VSL1 058989,000277: 23,3453 00031 24D 058990,000278: 23,3454 53520 XCHX,1 UNIT 058991,000279: 23,3455 00036 30D 058992,000280: 23,3456 06736 STORE XDC +18D,1 # XDC = L+J+K YDC = L+J+K ZDC = L+J+K 058993,000281: 058994,000282: 23,3457 77700 TIX,1 058995,000283: 23,3460 47461 AXISGEN3 058996,000284: 058997,000285: 23,3461 77704 AXISGEN3 TIX,2 058998,000286: 23,3462 47436 AXISGEN2 058999,000287: 059000,000288: 23,3463 77775 VLOAD 059001,000289: 23,3464 02714 XDC 059002,000290: 23,3465 26736 STOVL STARAD 059003,000291: 23,3466 02722 YDC 059004,000292: 23,3467 26744 STOVL STARAD +6 059005,000293: 23,3470 02730 ZDC 059006,000294: 23,3471 02752 STORE STARAD +12D 059007,000295: 059008,000296: 23,3472 77616 RVQ 059009,000297: 059010,000298: # Page 1363 059011,000299: 23,3473 05520 26075 QTSN45 2DEC .1768 059012,000300: 23,3475 05252 25253 .166... 2DEC .1666666667 059013,000301: 059014,000302: # Page 1364 (empty page) 059015,000303: 059016,000304: End of include-file INFLIGHT_ALIGNMENT_ROUTINES.agc. Parent file is MAIN.agc