Source Code
These source-code files are part of a reconstructed copy of Luminary 178, the
final release of the Apollo 14 Lunar Module (LM) Apollo Guidance Computer
(AGC) software.
The reconstruction began with source code of Zerlina 56, Luminary 210, and Luminary 131, previously transcribed from digitized copies of those programs. The code was created by combining the three, using Zerlina 56 as a base, since it was based off of Luminary 183. The differences between the three were carefully merged using the Luminary memos as a guide, with all changes made after Luminary 178 being backed out. The reconstruction was verified by matching memory-bank checksums to those listed in drawing 2021152N. Note that page numbers in the reconstructed code match those for the baseline log section mentioned in each file's changelog; the page numbers for a real Luminary 178 listing would be different. Comments from the original source code are prefixed with a single '#' symbol, whereas comments added later are prefixed by "##" or "###". Report any errors noted by creating an issue report at the Virtual AGC project's GitHub repository. |
052982,000002: ## Copyright: Public domain.
052983,000003: ## Filename: INFLIGHT_ALIGNMENT_ROUTINES.agc
052984,000004: ## Purpose: A section of Luminary revision 178.
052985,000005: ## It is part of the reconstructed source code for the final
052986,000006: ## release of the flight software for the Lunar Module's
052987,000007: ## (LM) Apollo Guidance Computer (AGC) for Apollo 14. The
052988,000008: ## code has been recreated from copies of Zerlina 56, Luminary
052989,000009: ## 210, and Luminary 131, as well as many Luminary memos.
052990,000010: ## It has been adapted such that the resulting bugger words
052991,000011: ## exactly match those specified for Luminary 178 in NASA
052992,000012: ## drawing 2021152N, which gives relatively high confidence
052993,000013: ## that the reconstruction is correct.
052994,000014: ## Reference: pp. 1238-1247
052995,000015: ## Assembler: yaYUL
052996,000016: ## Contact: Ron Burkey <info@sandroid.org>.
052997,000017: ## Website: www.ibiblio.org/apollo/index.html
052998,000018: ## Mod history: 2019-08-14 MAS Created from Zerlina 56.
052999,000019:
Page 1238 |
053001,000021: 22,3772 BANK 22
053002,000022: 23,2000 SETLOC INFLIGHT
053003,000023: 23,2000 BANK
053004,000024:
053005,000025: 23,3215 E5,1642 EBANK= XSM
053006,000026:
053007,000027: # CALCGTA COMPUTES THE GYRO TORQUE ANGLES REQUIRED TO BRING THE STABLE MEMBER INTO THE DESIRED ORIENTATION.
053008,000028:
053009,000029: # THE INPUT IS THE DESIRED STABLE MEMBER COORDINATES REFERRED TO PRESENT STABLE MEMBER COORDINATES. THE THREE
053010,000030: # HALF-UNIT VECTORS ARE STORED AT XDC, YDC, AND ZDC.
053011,000031:
053012,000032: # THE OUTPUTS ARE THE THREE GYRO TORQUING ANGLES TO BE APPLIED TO THE Y, Z, AND X GYROS AND ARE STORED DP AT IGC,
053013,000033: # MGC, AND OGC RESPECTIVELY.
053014,000034:
053015,000035: 23,3215 COUNT* $$/INFLT
053016,000036: 23,3215 71220 CALCGTA ITA DLOAD # PUSHDOWN 00-03,16D-27D,34D-37D
053017,000037: 23,3216 00051 S2 # XDC = (XD1 XD2 XD3)
053018,000038: 23,3217 02665 XDC # YDC = (YD1 YD2 YD3)
053019,000039: 23,3220 65325 PDDL PDDL # ZDC = (ZD1 ZD2 ZD3)
053020,000040: 23,3221 06470 HI6ZEROS
053021,000041: 23,3222 02671 XDC +4
053022,000042: 23,3223 55476 DCOMP VDEF
053023,000043: 23,3224 77656 UNIT
053024,000044: 23,3225 14027 STODL ZPRIME # ZP = UNIT(-XD3 0 XD1) = (ZP1 ZP2 ZP3)
053025,000045: 23,3226 00027 ZPRIME
053026,000046:
053027,000047: 23,3227 77742 SR1
053028,000048: 23,3230 14023 STODL SINTH # SIN(IGC) = ZP1
053029,000049: 23,3231 00033 ZPRIME +4
053030,000050: 23,3232 77742 SR1
053031,000051: 23,3233 34021 STCALL COSTH # COS(IGC) = ZP3
053032,000052: 23,3234 47266 ARCTRIG
053033,000053:
053034,000054: 23,3235 16742 STODL IGC # Y GYRO TORQUING ANGLE FRACTION OF REV.
053035,000055: 23,3236 02667 XDC +2
053036,000056: 23,3237 77742 SR1
053037,000057: 23,3240 14023 STODL SINTH # SIN(MGC) = XD2
053038,000058: 23,3241 00027 ZPRIME
053039,000059:
053040,000060: 23,3242 65205 DMP PDDL
053041,000061: 23,3243 02671 XDC +4 # PD00 = (ZP1)(XD3)
053042,000062: 23,3244 00033 ZPRIME +4
053043,000063:
053044,000064: 23,3245 45205 DMP DSU
053045,000065: 23,3246 02665 XDC # MPAC = (ZP3)(XD1)
053046,000066: 23,3247 77626 STADR
053047,000067: 23,3250 43756 STCALL COSTH # COS(MGC) = MPAC - PD00
053048,000068: 23,3251 47266 ARCTRIG
Page 1239 |
053050,000070: 23,3252 26744 STOVL MGC # Z GYRO TORQUING ANGLE FRACTION OF REV.
053051,000071: 23,3253 00027 ZPRIME
053052,000072: 23,3254 77641 DOT
053053,000073: 23,3255 02701 ZDC
053054,000074: 23,3256 24021 STOVL COSTH # COS(OGC) = ZP . ZDC
053055,000075: 23,3257 00027 ZPRIME
053056,000076: 23,3260 77641 DOT
053057,000077: 23,3261 02673 YDC
053058,000078: 23,3262 34023 STCALL SINTH # SIN(OGC) = ZP . YDC
053059,000079: 23,3263 47266 ARCTRIG
053060,000080:
053061,000081: 23,3264 36740 STCALL OGC # X GYRO TORQUING ANGLE FRACTION OF REV.
053062,000082: 23,3265 00051 S2
053063,000083:
Page 1240 |
053065,000085: # ARCTRIG COMPUTES AN ANGLE GIVEN THE SINE AND COSINE OF THIS ANGLE.
053066,000086:
053067,000087: # THE INPUTS ARE SIN/4 AND COS/4 STORED DP AT SINTH AND COSTH.
053068,000088:
053069,000089: # THE OUTPUT IS THE CALCULATED ANGLE BETWEEN +.5 AND -.5 REVOLUTIONS AND STORED AT THETA. THE OUTPUT IS ALSO
053070,000090: # AVAILABLE AT MPAC.
053071,000091:
053072,000092: 23,3266 51545 ARCTRIG DLOAD ABS # PUSHDOWN 16D-21D
053073,000093: 23,3267 00023 SINTH
053074,000094: 23,3270 50025 DSU BMN
053075,000095: 23,3271 07502 QTSN45 # ABS(SIN/4) - SIN(45)/4
053076,000096: 23,3272 47301 TRIG1 # IF (-45,45) OR (135,-135)
053077,000097:
053078,000098: 23,3273 72545 DLOAD SL1 # (45,135) OR (-135,-45)
053079,000099: 23,3274 00021 COSTH
053080,000100: 23,3275 75326 ACOS SIGN
053081,000101: 23,3276 00023 SINTH
053082,000102: 23,3277 00025 STORE THETA # X = ARCCOS(COS) WITH SIGN(SIN)
053083,000103: 23,3300 77616 RVQ
053084,000104:
053085,000105: 23,3301 72545 TRIG1 DLOAD SL1 # (-45,45) OR (135,-135)
053086,000106: 23,3302 00023 SINTH
053087,000107: 23,3303 77736 ASIN
053088,000108: 23,3304 14025 STODL THETA # X = ARCSIN(SIN) WITH SIGN(SIN)
053089,000109: 23,3305 00021 COSTH
053090,000110: 23,3306 77640 BMN
053091,000111: 23,3307 47312 TRIG2 # IF (135,-135)
053092,000112:
053093,000113: 23,3310 43545 DLOAD RVQ
053094,000114: 23,3311 00025 THETA # X = ARCSIN(SIN) (-45,45)
053095,000115:
053096,000116: 23,3312 75345 TRIG2 DLOAD SIGN # (135,-135)
053097,000117: 23,3313 06466 HIDPHALF
053098,000118: 23,3314 00023 SINTH
053099,000119: 23,3315 77625 DSU
053100,000120: 23,3316 00025 THETA
053101,000121: 23,3317 00025 STORE THETA # X = .5 WITH SIGN(SIN) - ARCSIN(SIN)
053102,000122: 23,3320 77616 RVQ # (+) - (+) OR (-) - (-)
053103,000123:
Page 1241 |
053105,000125: # SMNB, NBSM, AND AXISROT, WHICH USED TO APPEAR HERE, HAVE BEEN
053106,000126: # COMBINED IN A ROUTINE CALLED AX*SR*T, WHICH APPEARS AMONG THE POWERED
053107,000127: # FLIGHT SUBROUTINES.
053108,000128:
Page 1242 |
053110,000130: # CALCGA COMPUTES THE CDU DRIVING ANGLES REQUIRED TO BRING THE STABLE MEMBER INTO THE DESIRED ORIENTATION.
053111,000131:
053112,000132: # THE INPUTS ARE 1) THE NAVIGATION BASE COORDINATES REFERRED TO ANY COORDINATE SYSTEM. THE THREE HALF-UNIT
053113,000133: # VECTORS ARE STORED AT XNB,YNB, AND ZNB. 2) THE DESIRED STABLE MEMBER COORDINATES REFERRED TO THE SAME
053114,000134: # COORDINATE SYSTEM ARE STORED AT XSM, YSM, AND ZSM.
053115,000135:
053116,000136: # THE OUTPUTS ARE THE THREE CDU DRIVING ANGLES AND ARE STORED SP AT THETAD, THETAD +1, AND THETAD +2.
053117,000137:
053118,000138: 23,3321 77601 CALCGA SETPD # PUSHDOWN 00-05, 16D-21D, 34D-37D
053119,000139: 23,3322 00001 0
053120,000140: 23,3323 47375 VLOAD VXV
053121,000141: 23,3324 02665 XNB # XNB = OGA (OUTER GIMBAL AXIS)
053122,000142: 23,3325 02651 YSM # YSM = IGA (INNER GIMBAL AXIS)
053123,000143: 23,3326 41456 UNIT PUSH # PD0 = UNIT(OGA X IGA) = MGA
053124,000144:
053125,000145: 23,3327 44041 DOT ITA
053126,000146: 23,3330 02701 ZNB
053127,000147: 23,3331 00051 S2
053128,000148: 23,3332 24021 STOVL COSTH # COS(OG) = MGA . ZNB
053129,000149: 23,3333 00001 0
053130,000150: 23,3334 77641 DOT
053131,000151: 23,3335 02673 YNB
053132,000152: 23,3336 34023 STCALL SINTH # SIN(OG) = MGA . YNB
053133,000153: 23,3337 47266 ARCTRIG
053134,000154: 23,3340 26740 STOVL OGC
053135,000155: 23,3341 00001 0
053136,000156:
053137,000157: 23,3342 50235 VXV DOT # PROVISION FOR MG ANGLE OF 90 DEGREES
053138,000158: 23,3343 02665 XNB
053139,000159: 23,3344 02651 YSM
053140,000160: 23,3345 77752 SL1
053141,000161: 23,3346 24021 STOVL COSTH # COS(MG) = IGA . (MGA X OGA)
053142,000162: 23,3347 02651 YSM
053143,000163: 23,3350 77641 DOT
053144,000164: 23,3351 02665 XNB
053145,000165: 23,3352 34023 STCALL SINTH # SIN(MG) = IGA . OGA
053146,000166: 23,3353 47266 ARCTRIG
053147,000167: 23,3354 02744 STORE MGC
053148,000168:
053149,000169: 23,3355 45246 ABS DSU
053150,000170: 23,3356 07504 .166...
053151,000171: 23,3357 77644 BPL
053152,000172: 23,3360 47377 GIMLOCK1 # IF ANGLE GREATER THAN 60 DEGREES
053153,000173:
053154,000174: 23,3361 50375 CALCGA1 VLOAD DOT
053155,000175: 23,3362 02657 ZSM
053156,000176: 23,3363 00001 0
053157,000177: 23,3364 24021 STOVL COSTH # COS(IG) = ZSM . MGA
053158,000178: 23,3365 02643 XSM
Page 1243 |
053160,000180: 23,3366 45441 DOT STADR
053161,000181: 23,3367 43754 STCALL SINTH # SIN(IG) = XSM . MGA
053162,000182: 23,3370 47266 ARCTRIG
053163,000183:
053164,000184: 23,3371 26742 STOVL IGC
053165,000185: 23,3372 02740 OGC
053166,000186: 23,3373 77634 RTB
053167,000187: 23,3374 21621 V1STO2S
053168,000188: 23,3375 34322 STCALL THETAD
053169,000189: 23,3376 00051 S2
053170,000190:
053171,000191: 23,3377 77776 GIMLOCK1 EXIT
053172,000192: 23,3400 05600 TC ALARM
053173,000193: 23,3401 00401 OCT 00401
053174,000194: 23,3402 05515 TC UPFLAG # GIMBAL LOCK HAS OCCURED
053175,000195: 23,3403 00056 ADRES GLOKFAIL
053176,000196:
053177,000197: 23,3404 06042 TC INTPRET
053178,000198: 23,3405 77650 GOTO
053179,000199: 23,3406 47361 CALCGA1
053180,000200:
Page 1244 |
053182,000202: # AXISGEN COMPUTES THE COORDINATES OF ONE COORDINATE SYSTEM REFERRED TO ANOTHER COORDINATE SYSTEM.
053183,000203:
053184,000204: # THE INPUTS ARE 1) THE STAR1 VECTOR REFERRED TO COORDINATE SYSTEM A STORED AT STARAD. 2) THE STAR2 VECTOR
053185,000205: # REFERRED TO COORDINATE SYSTEM A STORED AT STARAD +6. 3) THE STAR1 VECTOR REFERRED TO COORDINATE SYSTEM B STORED
053186,000206: # AT LOCATION 6 OF THE VAC AREA. 4) THE STAR2 VECTOR REFERRED TO COORDINATE SYSTEM B STORED AT LOCATION 12D OF
053187,000207: # THE VAC AREA.
053188,000208:
053189,000209: # THE OUTPUT DEFINES COORDINATE SYSTEM A REFERRED TO COORDINATE SYSTEM B. THE THREE HALF-UNIT VECTORS ARE STORED
053190,000210: # AT LOCATIONS XDC, XDC +6, XDC +12D, AND STARAD, STARAD +6, STARAD +12D.
053191,000211:
053192,000212: 23,3407 66370 AXISGEN AXT,1 SSP # PUSHDOWN 00-30D,34D-37D
053193,000213: 23,3410 02714 STARAD +6
053194,000214: 23,3411 00051 S1
053195,000215: 23,3412 02700 STARAD -6
053196,000216:
053197,000217: 23,3413 77601 SETPD
053198,000218: 23,3414 00001 0
053199,000219: 23,3415 46773 AXISGEN1 VLOAD* VXV* # 06D UA = S1
053200,000220: 23,3416 02723 STARAD +12D,1 # STARAD +00D UB = S1
053201,000221: 23,3417 02731 STARAD +18D,1
053202,000222: 23,3420 77656 UNIT # 12D VA = UNIT(S1 X S2)
053203,000223: 23,3421 06731 STORE STARAD +18D,1 # STARAD +06D VB = UNIT(S1 X S2)
053204,000224: 23,3422 77773 VLOAD*
053205,000225: 23,3423 02723 STARAD +12D,1
053206,000226:
053207,000227: 23,3424 76433 VXV* VSL1
053208,000228: 23,3425 02731 STARAD +18D,1 # 18D WA = UA X VA
053209,000229: 23,3426 06737 STORE STARAD +24D,1 # STARAD +12D WB = UB X VB
053210,000230:
053211,000231: 23,3427 77700 TIX,1
053212,000232: 23,3430 47415 AXISGEN1
053213,000233:
053214,000234: 23,3431 66160 AXC,1 SXA,1
053215,000235: 23,3432 00006 6
053216,000236: 23,3433 00036 30D
053217,000237:
053218,000238: 23,3434 66370 AXT,1 SSP
053219,000239: 23,3435 00022 18D
053220,000240: 23,3436 00051 S1
053221,000241: 23,3437 00006 6
053222,000242:
053223,000243: 23,3440 66374 AXT,2 SSP
053224,000244: 23,3441 00006 6
053225,000245: 23,3442 00052 S2
053226,000246: 23,3443 00002 2
053227,000247:
053228,000248: 23,3444 76720 AXISGEN2 XCHX,1 VLOAD*
053229,000249: 23,3445 00036 30D # X1=-6 X2=+6 X1=-6 X2=+4 X1=-6 X2=+2
053230,000250: 23,3446 00001 0,1
053231,000251:
Page 1245 |
053233,000253: 23,3447 62757 VXSC* PDVL* # J=(UA)(UB1) J=(UA)(UB2) J=(UA)(UB3)
053234,000254: 23,3450 75062 STARAD +6,2
053235,000255: 23,3451 00007 6,1
053236,000256: 23,3452 77757 VXSC*
053237,000257: 23,3453 75054 STARAD +12D,2
053238,000258: 23,3454 30031 STOVL* 24D # K=(VA)(VB1) J=(VA)(VB2) J=(VA)(VB3)
053239,000259: 23,3455 00015 12D,1
053240,000260:
053241,000261: 23,3456 53357 VXSC* VAD
053242,000262: 23,3457 75046 STARAD +18D,2 # L=(WA)(WB1) J=(WA)(WB2) J=(WA)(WB3)
053243,000263: 23,3460 76455 VAD VSL1
053244,000264: 23,3461 00031 24D
053245,000265: 23,3462 53520 XCHX,1 UNIT
053246,000266: 23,3463 00036 30D
053247,000267: 23,3464 06707 STORE XDC +18D,1 # XDC = L+J+K YDC = L+J+K ZDC = L+J+K
053248,000268:
053249,000269: 23,3465 77700 TIX,1
053250,000270: 23,3466 47467 AXISGEN3
053251,000271:
053252,000272: 23,3467 77704 AXISGEN3 TIX,2
053253,000273: 23,3470 47444 AXISGEN2
053254,000274:
053255,000275: 23,3471 77775 VLOAD
053256,000276: 23,3472 02665 XDC
053257,000277: 23,3473 26707 STOVL STARAD
053258,000278: 23,3474 02673 YDC
053259,000279: 23,3475 26715 STOVL STARAD +6
053260,000280: 23,3476 02701 ZDC
053261,000281: 23,3477 02723 STORE STARAD +12D
053262,000282:
053263,000283: 23,3500 77616 RVQ
053264,000284:
Page 1246 |
053266,000286: 23,3501 05520 26075 QTSN45 2DEC .1768
053267,000287: 23,3503 05252 25253 .166... 2DEC .1666666667
053268,000288:
Page 1247 There is no source code on this page of the original assembly listing. |
End of include-file INFLIGHT_ALIGNMENT_ROUTINES.agc. Parent file is MAIN.agc