Source Code
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These source-code files were obtained by digitally photographing the
Colossus 237 program listing from the private collection of original
AGC developer Fred Martin, and then modifying pre-existing Colossus 249
(Apollo 9) source files to incorporate changes. Note that the page images
presented online are of reduced quality, and that additional images
are available. Report any conversion errors or legibility
problems in page images to info@sandroid.org.
Notations on the program listing read, in part:GAP: ASSEMBLE REVISION 237 OF AGC PROGRAM COLOSSUS BY NASA 2021111-031 1:17 AUG. 24, 1968 |
055879,000002: # Copyright: Public domain.
055880,000003: # Filename: INFLIGHT_ALIGNMENT_ROUTINES.agc
055881,000004: # Purpose: Part of the source code for Colossus build 237.
055882,000005: # This is for the Command Module's (CM) Apollo Guidance
055883,000006: # Computer (AGC), we believe for Apollo 8.
055884,000007: # Assembler: yaYUL
055885,000008: # Contact: Jim Lawton <jim DOT lawton AT gmail DOT com>
055886,000009: # Website: www.ibiblio.org/apollo/index.html
055887,000010: # Page scans: www.ibiblio.org/apollo/ScansForConversion/Colossus237/
055888,000011: # Mod history: 2011-04-17 JL Adapted from corresponding Colossus 249 file.
055889,000012:
055890,000013: # # Page 1319
055891,000014: 22,3505 BANK 22
055892,000015: 23,2000 SETLOC INFLIGHT
055893,000016: 23,2000 BANK
055894,000017:
055895,000018: 23,3140 0002671 EBANK= XSM
055896,000019:
055897,000020:
055898,000021: # CALCGTA COMPUTES THE GYRO TORQUE ANGLES REQUIRED TO BRING THE STABLE MEMBER INTO THE DESIRED ORIENTATION.
055899,000022:
055900,000023: # THE INPUT IS THE DESIRED STABLE MEMBER COORDINATES REFERRED TO PRESENT STABLE MEMBER COORDINATES. THE THREE
055901,000024: # HALF-UNIT VECTORS ARE STORED AT XDC, YDC, AND ZDC.
055902,000025:
055903,000026: # THE OUTPUTS ARE THE THREE GYRO TORQUE ANGLES TO BE APPLIED TO THE Y, Z, AND X GYROS AND ARE STORED DP AT IGC,
055904,000027: # MGC, AND OGC RESPECTIVELY.
055905,000028:
055906,000029: 23,3140 COUNT 23/INFLT
055907,000030:
055908,000031: 23,3140 71220 CALCGTA ITA DLOAD # PUSHDOWN 00-03,16D-27D,34D-37D
055909,000032: 23,3141 00051 S2 # XDC = (XD1 XD2 XD3)
055910,000033: 23,3142 02714 XDC # YDC = (YD1 YD2 YD3)
055911,000034: 23,3143 65325 PDDL PDDL # ZDC = (ZD1 ZD2 ZD3)
055912,000035: 23,3144 15332 HI6ZEROS
055913,000036: 23,3145 02720 XDC +4
055914,000037: 23,3146 55476 DCOMP VDEF
055915,000038: 23,3147 77656 UNIT
055916,000039: 23,3150 14027 STODL ZPRIME # ZP = UNIT(-XD3 0 XD1) = (ZP1 ZP2 ZP3)
055917,000040: 23,3151 00027 ZPRIME
055918,000041:
055919,000042: 23,3152 77742 SR1
055920,000043: 23,3153 14023 STODL SINTH # SIN(IGC) = ZP1
055921,000044: 23,3154 00033 ZPRIME +4
055922,000045: 23,3155 77742 SR1
055923,000046: 23,3156 34021 STCALL COSTH # COS(IGC) = ZP3
055924,000047: 23,3157 47211 ARCTRIG
055925,000048:
055926,000049: 23,3160 16762 STODL IGC # Y GYRO TORQUING ANGLE FRACTION OF REV.
055927,000050: 23,3161 02716 XDC +2
055928,000051: 23,3162 77742 SR1
055929,000052: 23,3163 14023 STODL SINTH # SIN(MGC) = XD2
055930,000053: 23,3164 00027 ZPRIME
055931,000054:
055932,000055: 23,3165 65205 DMP PDDL
055933,000056: 23,3166 02720 XDC +4 # PD00 = (ZP1)(XD3)
055934,000057: 23,3167 00033 ZPRIME +4
055935,000058:
055936,000059: 23,3170 45205 DMP DSU
055937,000060: 23,3171 02714 XDC # MPAC = (ZP3)(XD1)
055938,000061: 23,3172 77626 STADR
055939,000062: 23,3173 43756 STCALL COSTH # COS(MGC) = MPAC - PD00
055940,000063: 23,3174 47211 ARCTRIG
055941,000064: # # Page 1320
055942,000065: 23,3175 26764 STOVL MGC # Z GYRO TORQUING ANGLE FRACTION OF REV.
055943,000066: 23,3176 00027 ZPRIME
055944,000067: 23,3177 77641 DOT
055945,000068: 23,3200 02730 ZDC
055946,000069: 23,3201 24021 STOVL COSTH # COS(OGC) = ZP . ZDC
055947,000070: 23,3202 00027 ZPRIME
055948,000071: 23,3203 77641 DOT
055949,000072: 23,3204 02722 YDC
055950,000073: 23,3205 34023 STCALL SINTH # SIN(OGC) = ZP . YDC
055951,000074: 23,3206 47211 ARCTRIG
055952,000075:
055953,000076: 23,3207 36760 STCALL OGC # X GYRO TORQUING ANGLE FRACTION OF REV.
055954,000077: 23,3210 00051 S2
055955,000078:
055956,000079: # # Page 1321
055957,000080: # ARCTRIG COMPUTES AN ANGLE GIVEN THE SINE AND COSINE OF THIS ANGLE.
055958,000081:
055959,000082: # THE INPUTS ARE SIN/4 AND COS/4 STORED DP AT SINTH AND COSTH.
055960,000083:
055961,000084: # THE OUTPUT IS THE CALCULATED ANGLE BETWEEN +.5 AND -.5 REVOLUTIONS AND STORED AT THETA. THE OUTPUT IS ALSO
055962,000085: # AVAILABLE AT MPAC.
055963,000086:
055964,000087:
055965,000088: 23,3211 51545 ARCTRIG DLOAD ABS # PUSHDOWN 16D-21D
055966,000089: 23,3212 00023 SINTH
055967,000090: 23,3213 50025 DSU BMN
055968,000091: 23,3214 07427 QTSN45 # ABS(SIN/4) - SIN(45)/4
055969,000092: 23,3215 47224 TRIG1 # IF (-45,45) OR (135,-135)
055970,000093:
055971,000094:
055972,000095: 23,3216 72545 DLOAD SL1 # (45,135) OR (-135,-45)
055973,000096: 23,3217 00021 COSTH
055974,000097: 23,3220 75326 ACOS SIGN
055975,000098: 23,3221 00023 SINTH
055976,000099: 23,3222 00025 STORE THETA # X = ARCCOS(COS) WITH SIGN(SIN)
055977,000100: 23,3223 77616 RVQ
055978,000101:
055979,000102:
055980,000103: 23,3224 72545 TRIG1 DLOAD SL1 # (-45,45) OR (135,-135)
055981,000104: 23,3225 00023 SINTH
055982,000105: 23,3226 77736 ASIN
055983,000106: 23,3227 14025 STODL THETA # X = ARCSIN(SIN) WITH SIGN(SIN)
055984,000107: 23,3230 00021 COSTH
055985,000108: 23,3231 77640 BMN
055986,000109: 23,3232 47235 TRIG2 # IF (135,-135)
055987,000110:
055988,000111: 23,3233 43545 DLOAD RVQ
055989,000112: 23,3234 00025 THETA # X = ARCSIN(SIN) (-45,45)
055990,000113:
055991,000114:
055992,000115: 23,3235 75345 TRIG2 DLOAD SIGN # (135,-135)
055993,000116: 23,3236 15330 HIDPHALF
055994,000117: 23,3237 00023 SINTH
055995,000118: 23,3240 77625 DSU
055996,000119: 23,3241 00025 THETA
055997,000120: 23,3242 00025 STORE THETA # X = .5 WITH SIGN(SIN) - ARCSIN(SIN)
055998,000121: 23,3243 77616 RVQ # (+) - (+) OR (-) - (-)
055999,000122:
056000,000123: # # Page 1322
056001,000124: # SMNB, NBSM, AND AXISROT, WHICH USED TO APPEAR HERE, HAVE BEEN
056002,000125: # COMBINED IN A ROUTINE CALLED AX*SR*T, WHICH APPEARS AMONG THE POWERED
056003,000126: # FLIGHT SUBROUTINES.
056004,000127:
056005,000128: # # Page 1323
056006,000129: # CALCGA COMPUTES THE CDU DRIVING ANGLES REQUIRED TO BRING THE STABLE MEMBER INTO THE DESIRED ORIENTATION.
056007,000130:
056008,000131: # THE INPUTS ARE 1) THE NAVIGATION BASE COORDINATES REFERRED TO ANY COORDINATE SYSTEM. THE THREE HALF-UNIT
056009,000132: # VECTORS ARE STORED AT XNB,YNB, AND ZNB. 2) THE DESIRED STABLE MEMBER COORDINATES REFERRED TO THE SAME
056010,000133: # COORDINATE SYSTEM ARE STORED AT XSM, YSM, AND ZSM.
056011,000134:
056012,000135: # THE OUTPUTS ARE THE THREE CDU DRIVING ANGLES AND ARE STORED SP AT THETAD, THETAD +1, AND THETAD +2.
056013,000136:
056014,000137: 23,3244 77601 CALCGA SETPD # PUSHDOWN 00-05, 16D-21D, 34D-37D
056015,000138: 23,3245 00001 0
056016,000139: 23,3246 47375 VLOAD VXV
056017,000140: 23,3247 02714 XNB # XNB = OGA (OUTER GIMBAL AXIS)
056018,000141: 23,3250 02700 YSM # YSM = IGA (INNER GIMBAL AXIS)
056019,000142: 23,3251 41456 UNIT PUSH # PD0 = UNIT(OGA X IGA) = MGA
056020,000143:
056021,000144: 23,3252 44041 DOT ITA
056022,000145: 23,3253 02730 ZNB
056023,000146: 23,3254 00051 S2
056024,000147: 23,3255 24021 STOVL COSTH # COS(OG) = MGA . ZNB
056025,000148: 23,3256 00001 0
056026,000149: 23,3257 77641 DOT
056027,000150: 23,3260 02722 YNB
056028,000151: 23,3261 34023 STCALL SINTH # SIN(OG) = MGA . YNB
056029,000152: 23,3262 47211 ARCTRIG
056030,000153: 23,3263 26760 STOVL OGC
056031,000154: 23,3264 00001 0
056032,000155:
056033,000156: 23,3265 50235 VXV DOT # PROVISION FOR MG ANGLE OF 90 DEGREES
056034,000157: 23,3266 02714 XNB
056035,000158: 23,3267 02700 YSM
056036,000159: 23,3270 77752 SL1
056037,000160: 23,3271 24021 STOVL COSTH # COS(MG) = IGA . (MGA X OGA)
056038,000161: 23,3272 02700 YSM
056039,000162: 23,3273 77641 DOT
056040,000163: 23,3274 02714 XNB
056041,000164: 23,3275 34023 STCALL SINTH # SIN(MG) = IGA . OGA
056042,000165: 23,3276 47211 ARCTRIG
056043,000166: 23,3277 02764 STORE MGC
056044,000167:
056045,000168: 23,3300 45246 ABS DSU
056046,000169: 23,3301 07431 .166...
056047,000170: 23,3302 77644 BPL
056048,000171: 23,3303 47324 GIMLOCK1 # IF ANGLE GREATER THAN 60 DEGREES
056049,000172:
056050,000173: 23,3304 50375 CALCGA1 VLOAD DOT
056051,000174: 23,3305 02706 ZSM
056052,000175: 23,3306 00001 0
056053,000176: 23,3307 24021 STOVL COSTH # COS(IG) = ZSM . MGA
056054,000177: 23,3310 02672 XSM
056055,000178: # # Page 1324
056056,000179: 23,3311 45441 DOT STADR
056057,000180: 23,3312 43754 STCALL SINTH # SIN(IG) = XSM . MGA
056058,000181: 23,3313 47211 ARCTRIG
056059,000182:
056060,000183: 23,3314 26762 STOVL IGC
056061,000184: 23,3315 02760 OGC
056062,000185: 23,3316 43034 RTB BONCLR
056063,000186: 23,3317 45547 V1STO2S
056064,000187: 23,3320 00200 CPHIFLAG
056065,000188: 23,3321 00051 S2
056066,000189: 23,3322 35156 STCALL THETAD
056067,000190: 23,3323 00051 S2
056068,000191:
056069,000192: 23,3324 77776 GIMLOCK1 EXIT
056070,000193: 23,3325 05537 TC ALARM
056071,000194: 23,3326 00401 OCT 00401
056072,000195: 23,3327 05435 TC UPFLAG # GIMBAL LOCK HAS OCCURED
056073,000196: 23,3330 00056 ADRES GLOKFAIL
056074,000197:
056075,000198: 23,3331 06006 TC INTPRET
056076,000199: 23,3332 77650 GOTO
056077,000200: 23,3333 47304 CALCGA1
056078,000201:
056079,000202: # # Page 1325
056080,000203: # AXISGEN COMPUTES THE COORDINATES OF ONE COORDINATE SYSTEM REFERRED TO ANOTHER COORDINATE SYSTEM.
056081,000204:
056082,000205: # THE INPUTS ARE 1) THE STAR1 VECTOR REFERRED TO COORDINATE SYSTEM A STORED AT STARAD. 2) THE STAR2 VECTOR
056083,000206: # REFERRED TO COORDINATE SYSTEM A STORED AT STARAD +6. 3) THE STAR1 VECTOR REFERRED TO COORDINATE SYSTEM B STORED
056084,000207: # AT LOCATION 6 OF THE VAC AREA. 4) THE STAR2 VECTOR REFERRED TO COORDINATE SYSTEM B STORED AT LOCATION 12D OF
056085,000208: # THE VAC AREA.
056086,000209:
056087,000210: # THE OUTPUT DEFINES COORDINATE SYSTEM A REFERRED TO COORDINATE SYSTEM B. THE THREE HALF-UNIT VECTORS ARE STORED
056088,000211: # AT LOCATIONS XDC, XDC +6, XDC +12D, AND STARAD, STARAD +6, STARAD +12D.
056089,000212:
056090,000213:
056091,000214: 23,3334 66370 AXISGEN AXT,1 SSP # PUSHDOWN 00-30D,34D-37D
056092,000215: 23,3335 02743 STARAD +6
056093,000216: 23,3336 00051 S1
056094,000217: 23,3337 02727 STARAD -6
056095,000218:
056096,000219: 23,3340 77601 SETPD
056097,000220: 23,3341 00001 0
056098,000221: 23,3342 46773 AXISGEN1 VLOAD* VXV* # 06D UA = S1
056099,000222: 23,3343 02752 STARAD +12D,1 # STARAD +00D UB = S1
056100,000223: 23,3344 02760 STARAD +18D,1
056101,000224: 23,3345 77656 UNIT # 12D VA = UNIT(S1 X S2)
056102,000225: 23,3346 06760 STORE STARAD +18D,1 # STARAD +06D VB = UNIT(S1 X S2)
056103,000226: 23,3347 77773 VLOAD*
056104,000227: 23,3350 02752 STARAD +12D,1
056105,000228:
056106,000229: 23,3351 76433 VXV* VSL1
056107,000230: 23,3352 02760 STARAD +18D,1 # 18D WA = UA X VA
056108,000231: 23,3353 06766 STORE STARAD +24D,1 # STARAD +12D WB = UB X VB
056109,000232:
056110,000233: 23,3354 77700 TIX,1
056111,000234: 23,3355 47342 AXISGEN1
056112,000235:
056113,000236: 23,3356 66160 AXC,1 SXA,1
056114,000237: 23,3357 00006 6
056115,000238: 23,3360 00036 30D
056116,000239:
056117,000240: 23,3361 66370 AXT,1 SSP
056118,000241: 23,3362 00022 18D
056119,000242: 23,3363 00051 S1
056120,000243: 23,3364 00006 6
056121,000244:
056122,000245: 23,3365 66374 AXT,2 SSP
056123,000246: 23,3366 00006 6
056124,000247: 23,3367 00052 S2
056125,000248: 23,3370 00002 2
056126,000249:
056127,000250: 23,3371 76720 AXISGEN2 XCHX,1 VLOAD*
056128,000251: 23,3372 00036 30D # X1=-6 X2=+6 X1=-6 X2=+4 X1=-6 X2=+2
056129,000252: 23,3373 00001 0,1
056130,000253: # # Page 1326
056131,000254: 23,3374 62757 VXSC* PDVL* # J=(UA)(UB1) J=(UA)(UB2) J=(UA)(UB3)
056132,000255: 23,3375 75033 STARAD +6,2
056133,000256: 23,3376 00007 6,1
056134,000257: 23,3377 77757 VXSC*
056135,000258: 23,3400 75025 STARAD +12D,2
056136,000259: 23,3401 30031 STOVL* 24D # K=(VA)(VB1) J=(VA)(VB2) J=(VA)(VB3)
056137,000260: 23,3402 00015 12D,1
056138,000261:
056139,000262: 23,3403 53357 VXSC* VAD
056140,000263: 23,3404 75017 STARAD +18D,2 # L=(WA)(WB1) J=(WA)(WB2) J=(WA)(WB3)
056141,000264: 23,3405 76455 VAD VSL1
056142,000265: 23,3406 00031 24D
056143,000266: 23,3407 53520 XCHX,1 UNIT
056144,000267: 23,3410 00036 30D
056145,000268: 23,3411 06736 STORE XDC +18D,1 # XDC = L+J+K YDC = L+J+K ZDC = L+J+K
056146,000269:
056147,000270: 23,3412 77700 TIX,1
056148,000271: 23,3413 47414 AXISGEN3
056149,000272:
056150,000273: 23,3414 77704 AXISGEN3 TIX,2
056151,000274: 23,3415 47371 AXISGEN2
056152,000275:
056153,000276: 23,3416 77775 VLOAD
056154,000277: 23,3417 02714 XDC
056155,000278: 23,3420 26736 STOVL STARAD
056156,000279: 23,3421 02722 YDC
056157,000280: 23,3422 26744 STOVL STARAD +6
056158,000281: 23,3423 02730 ZDC
056159,000282: 23,3424 02752 STORE STARAD +12D
056160,000283:
056161,000284: 23,3425 77616 RVQ
056162,000285:
056163,000286: # # Page 1327
056164,000287: 23,3426 05520 26075 QTSN45 2DEC .1768
056165,000288: 23,3430 05252 25253 .166... 2DEC .1666666667
056166,000289:
056167,000290: # # Page 1328
End of include-file INFLIGHT_ALIGNMENT_ROUTINES.agc. Parent file is MAIN.agc