Source Code
These source-code files are part of a reconstructed copy of Artemis 071, the
first release of the Apollo 15 through 17 Command Module (CM) Apollo Guidance
Computer (AGC) software.
The reconstruction began with source code of Artemis 072 previously transcribed from a digitized copy of that program. The code was then updated by undoing changes between the two versions. The reconstruction was verified by matching memory-bank checksums to those listed in drawing 2021154-. Note that page numbers in the reconstructed code match those on the Artemis 072 printout, although the changed code would likely have changed page numbers for a real Artemis 071 listing. 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. |
041998,000002: ## Copyright: Public domain.
041999,000003: ## Filename: TVCMASSPROP.agc
042000,000004: ## Purpose: A section of Artemis revision 071.
042001,000005: ## It is part of the reconstructed source code for the first
042002,000006: ## release of the flight software for the Command Module's
042003,000007: ## (CM) Apollo Guidance Computer (AGC) for Apollo 15 through
042004,000008: ## 17. The code has been recreated from a copy of Artemis 072.
042005,000009: ## It has been adapted such that the resulting bugger words
042006,000010: ## exactly match those specified for Artemis 071 in NASA
042007,000011: ## drawing 2021154-, which gives relatively high confidence
042008,000012: ## that the reconstruction is correct.
042009,000013: ## Reference: 954
042010,000014: ## Assembler: yaYUL
042011,000015: ## Contact: Ron Burkey <info@sandroid.org>.
042012,000016: ## Website: www.ibiblio.org/apollo/index.html
042013,000017: ## Mod history: 2019-08-14 MAS Created from Artemis 072.
042014,000018:
Page 954 |
042016,000020:
042017,000021: # PROGRAM NAME....MASSPROP
042018,000022: # LOG SECTION....TVCMASSPROP PROGRAMMER...MELANSON (ENGEL, SCHLUNDT)
042019,000023:
042020,000024:
042021,000025: # FUNCTIONAL DESCRIPTION:
042022,000026:
042023,000027: # MASSPROP OPERATES IN TWO MODES:(1)IF LEM MASS OR CONFIGURATION ARE UPDATED (MASSPROP DOES NOT TEST
042024,000028: # FOR THIS) THE ENTIRE PROGRAM MUST BE RUN THROUGH, BREAKPOINT VALUES AND DERIVATIVES OF THE OUTPUTS WITH
042025,000029: # RESPECT TO CSM MASS BEING CALCULATED PRIOR TO CALCULATION OF THE OUTPUTS. (2)OTHERWISE, THE OUTPUTS CAN BE
042026,000030: # CALCULATED USING PREVIOUSLY COMPUTED BREAKPOINT VALUES AND DERIVATIVES.
042027,000031:
042028,000032: # CALLING SEQUENCES
042029,000033:
042030,000034: # IF LEM MASS OR CONFIGURATION HAS BEEN UPDATED, TRANSFER TO MASSPROP, OTHERWISE TRANSFER TO FIXCW.
042031,000035: # L TC BANKCALL OR IBNKCALL
042032,000036: # L+1 CADR MASSPROP
042033,000037: # OR
042034,000038: # L+1 CADR FIXCW
042035,000039:
042036,000040: # L+2 RETURNS VIA Q
042037,000041:
042038,000042: # CALLED IN PARTICULAR BY DONOUN47 (JOB) AND TVCEXECUTIVE (TASK)
042039,000043:
042040,000044: # JOBS OR TASKS INITIATED - NONE
042041,000045:
042042,000046: # SUBROUTINES CALLED - NONE
042043,000047:
042044,000048: # ERASABLE INITIALIZATION REQUIRED
042045,000049:
042046,000050: # LEMMASS MUST CONTAIN LEM MASS SCALED AT B+16 IN KILOGRAMS
042047,000051: # CSMMASS MUST CONTAIN CSM MASS SCALED AT B+16 IN KILOGRAMS
042048,000052:
042049,000053: # DAPDATR1 MUST BE SET TO INDICATE VEHICLE CONFIGURATION.
042050,000054: # BITS (15,14,13) = ( 0 , 0 , 1 ) LEM OFF
042051,000055: # ( 0 , 1 , 0 ) LEM ON (ASCNT,DSCNT)
042052,000056: # ( 1 , 1 , 0 ) LEM ON (ASCNT ONLY)
042053,000057:
042054,000058:
042055,000059: # ALARMS - NONE
042056,000060:
042057,000061: # EXIT - TC Q
042058,000062:
042059,000063: # OUTPUTS:
042060,000064:
042061,000065: # (1)IXX, SINGLE PRECISION SCALED AT B+20 IN KG-M SQ.
042062,000066: # (2)IAVG, SINGLE PRECISION SCALED AT B+20 IN KG-M SQ.
042063,000067: # (3)IAVG/TLX, SINGLE PRECISION, SCALED AT B+2 SEC-SQD
042064,000068: # THEY ARE STORED IN CONSECUTIVE REGISTERS IXX0, IXX1, IXX2
042065,000069:
042066,000070: # CONVERSION FACTOR: (SLUG-FTSQ) = 0.737562 (KG-MSQ)
042067,000071:
Page 955 |
042069,000073:
042070,000074: # OUTPUTS ARE CALCULATED AS FOLLOWS :
042071,000075:
042072,000076: # (1) IF LEM DOCKED, LEMMASS IS FIRST ELIMINATED AS A PARAMETER
042073,000077:
042074,000078: # VARST0 = INTVALUE0 + LEMMASS(SLOPEVAL0) IXX BREAKPOINT VALUE
042075,000079: # VARST1 = INTVALUE1 + LEMMASS(SLOPEVAL1) IAVG BREAKPOINT VALUE
042076,000080: # VARST2 = INTVALUE2 + LEMMASS(SLOPEVAL2) IAVG/TLX BREAKPOINT VALUE
042077,000081:
042078,000082: # VARST3 = INTVALUE3 + LEMMASS(SLOPEVAL3) IAVG/TLX SLOPE FOR CSMMASS > 33956 LBS ( SPS > 10000 LBS)
042079,000083: # VARST4 = INTVALUE4 + LEMMASS(SLOPEVAL4) IAVG SLOPE FOR CSMMASS > 33956 LBS ( SPS > 10000 LBS)
042080,000084:
042081,000085: # VARST5 = INTVALUE5 + LEMMASS(SLOPEVAL5) IXX SLOPE FOR ALL VALUES OF CSMMASS
042082,000086:
042083,000087: # VARST6 = INTVALUE6 + LEMMASS(SLOPEVAL6) IAVG SLOPE FOR CSMMASS < 33956 LBS ( SPS < 10000 LBS)
042084,000088: # VARST7 = INTVALUE7 + LEMMASS(SLOPEVAL7) IAVG/TLX SLOPE FOR CSMMASS < 33956 LBS ( SPS < 10000 LBS)
042085,000089:
042086,000090: # VARST8 = INTVALUE8 + LEMMASS(SLOPEVAL8) IAVG DECREMENT TO BRKPT VALUE WHEN LEM DSCNT STAGE OFF
042087,000091: # VARST9 = INTVALUE9 + LEMMASS(SLOPEVAL9) IAVG/TLX DECREMENT TO BRKPT VALUE WHEN LEM DSCNT STAGE OFF
042088,000092:
042089,000093: # (2) IF LEM NOT DOCKED
042090,000094:
042091,000095: # VARST0 = NOLEMVAL0 WHERE THE MEANING AND SCALING OF VARST0
042092,000096: # . . TO VARST9 ARE THE SAME AS GIVEN ABOVE
042093,000097: # . .
042094,000098: # . . NOTE... FOR THIS CASE, VARST8,9 HAVE NO
042095,000099: # VARST9 = NOLEMVAL9 MEANING (THEY ARE COMPUTED BUT NOT USED)
042096,000100:
042097,000101: # (3) THE FINAL OUTPUT CALCULATIONS ARE THEN DONE
042098,000102:
042099,000103: # IXX0 = VARST0 + (CSMMASS + NEGBPW)VARST5 IXX
042100,000104:
042101,000105: # IXX1 = VARST1 + (CSMMASS + NEGBPW)VARST(4 OR 6) IAVG
042102,000106:
042103,000107: # IXX2 = VARST2 + (CSMMASS + NEGBPW)VARST(3 OR 7) IAVG/TLX
042104,000108:
042105,000109: # THE DATA USED CAME FROM CSM/LM SPACECRAFT OPERATIONAL DATA BOOK.
042106,000110: # VOL. 3, NASA DOCUMENT SNA-8-D-027 (MARCH 1968)
042107,000111:
042108,000112: # PERTINENT MASS DATA : CSM WEIGHT (FULL) 64100 LBS
042109,000113: # (EMPTY) 23956 LBS
042110,000114: # LEM WEIGHT (FULL) 32000 LBS
042111,000115: # (EMPTY) 14116 LBS
042112,000116:
042113,000117: # (WEIGHTS ARE FROM AMENDMENT #1 (APRIL 24,1968) TO ABOVE DATA BOOK)
042114,000118:
Page 956 |
042116,000120: 05,2000 SETLOC DAPMASS
042117,000121: 05,2000 BANK
042118,000122: 05,3313 E6,1446 EBANK= CNTR
042119,000123: 05,3313 COUNT* $$/MASP
042120,000124:
042121,000125:
042122,000126: 05,3313 34322 MASSPROP CAF NINE # MASSPROP USES TVC/RCS INTERUPT TEMPS
042123,000127: 05,3314 55506 +1 TS PHI333 # SET UP TEN PASSES
042124,000128: 05,3315 31465 LEMTEST CAE DAPDATR1 # DETERMINE LEM STATUS
042125,000129: 05,3316 74754 MASK BIT13
042126,000130: 05,3317 00006 EXTEND
042127,000131: 05,3320 13324 BZF LEMYES
042128,000132:
042129,000133: 05,3321 51506 LEMNO INDEX PHI333 # LEM NOT ATTACHED
042130,000134: 05,3322 33410 CAF NOLEMVAL
042131,000135: 05,3323 13334 TCF STOINST
042132,000136:
042133,000137: 05,3324 31472 LEMYES CAE LEMMASS # LEM IS ATTACHED
042134,000138: 05,3325 60000 DOUBLE
042135,000139: 05,3326 00006 EXTEND
042136,000140: 05,3327 51506 INDEX PHI333
042137,000141: 05,3330 73432 MP SLOPEVAL
042138,000142: 05,3331 20001 DDOUBL
042139,000143: 05,3332 51506 INDEX PHI333
042140,000144: 05,3333 63420 AD INTVALUE
042141,000145:
042142,000146: 05,3334 51506 STOINST INDEX PHI333 # STORAGE INST BEGIN HERE
042143,000147: 05,3335 55511 TS VARST0
042144,000148: 05,3336 11506 CCS PHI333 # ARE ALL TEN PASSES COMPLETED
042145,000149: 05,3337 13314 TCF MASSPROP +1 # NO - GO DECREMENT PHI333
042146,000150:
042147,000151: 05,3340 11465 DXTEST CCS DAPDATR1 # IF NEG, BIT15 IS 1, LEM DSCNT STAGE OFF
042148,000152: 05,3341 13347 TCF FIXCW
042149,000153: 05,3342 13347 TCF FIXCW
042150,000154: 05,3343 53522 DXCH VARST0 +8D
042151,000155: 05,3344 21513 DAS VARST0 +1
042152,000156: 05,3345 33445 CA DXITFIX
042153,000157: 05,3346 27520 ADS VARST0 +7
042154,000158:
042155,000159: 05,3347 34767 FIXCW CAF BIT2 # COMPUTATION PHASE BEGINS HERE. SET UP
042156,000160: 05,3350 55506 TS PHI333 # THREE PASSES
042157,000161: 05,3351 55507 TS PSI333
042158,000162:
042159,000163: 05,3352 31473 CAE CSMMASS # GET DELTA CSM WEIGHT - SIGN DETERMINES
042160,000164: 05,3353 63444 AD NEGBPW # SLOPE LOCATIONS.
042161,000165: 05,3354 60000 DOUBLE
042162,000166: 05,3355 55510 TS TEMP333
042163,000167:
042164,000168: 05,3356 00006 EXTEND
042165,000169: 05,3357 63362 BZMF PEGGY # DETERMINE CORRECT SLOPE
Page 957 |
042167,000171: 05,3360 37701 CAF NEG2
042168,000172: 05,3361 55506 TS PHI333
042169,000173:
042170,000174: 05,3362 51506 PEGGY INDEX PHI333 # ALL IS READY - CALCULATE OUTPUTS NOW
042171,000175: 05,3363 31516 CAE VARST5 # GET SLOPE
042172,000176: 05,3364 00006 EXTEND
042173,000177: 05,3365 71510 MP TEMP333 # MULT BY DELTA CSM WEIGHT
042174,000178: 05,3366 60000 DOUBLE
042175,000179: 05,3367 51507 INDEX PSI333
042176,000180: 05,3370 61511 AD VARST0 # ADD BREAKPOINT VALUE
042177,000181: 05,3371 51507 INDEX PSI333
042178,000182: 05,3372 55467 TS IXX # ****** OUTPUTS (IXX0, IXX1, IXX2) ******
042179,000183:
042180,000184:
042181,000185: 05,3373 11507 CCS PSI333 # BOOKKEEPING - MASSPROP FINISHED OR NOT
042182,000186: 05,3374 13404 TCF BOKKEP2 # NO - GO TAKE CARE OF INDEXING REGISTERS
042183,000187:
042184,000188: 05,3375 31465 CAE DAPDATR1 # UPDATE WEIGHT/G
042185,000189: 05,3376 74753 MASK BIT14
042186,000190: 05,3377 10000 CCS A
042187,000191: 05,3400 31472 CA LEMMASS
042188,000192: 05,3401 61473 AD CSMMASS
042189,000193: 05,3402 55475 TS WEIGHT/G # SCALED AT B+16 IN KILOGRAMS
042190,000194: 05,3403 00002 ENDMASSP TC Q
042191,000195:
042192,000196: 05,3404 55507 BOKKEP2 TS PSI333 # REDUCE PSI BY ONE
042193,000197: 05,3405 00006 EXTEND
042194,000198: 05,3406 27506 DIM PHI333
042195,000199: 05,3407 13362 TCF PEGGY
042196,000200:
Page 958 |
042198,000202:
042199,000203: 05,3410 00616 NOLEMVAL DEC 25445. B-20
042200,000204: 05,3411 02526 DEC 87450. B-20
042201,000205: 05,3412 02352 DEC .30715 B-2
042202,000206: 05,3413 01471 DEC 1.22877 E-5 B+12
042203,000207: 05,3414 00634 DEC 1.6096 B-6
042204,000208: 05,3415 00612 DEC 1.54 B-6
042205,000209: 05,3416 03706 DEC 7.77177 B-6
042206,000210: 05,3417 04425 DEC 3.46458 E-5 B+12
042207,000211:
042208,000212: 05,3420 00644 INTVALUE DEC 26850 B-20
042209,000213: 05,3421 03710 DEC 127518 B-20
042210,000214: 05,3422 04246 DEC .54059 B-2
042211,000215: 05,3423 02011 DEC .153964 E-4 B+12
042212,000216: 05,3424 77501 DEC -.742923 B-6
042213,000217: 05,3425 00612 DEC 1.5398 B-6
042214,000218: 05,3426 04656 DEC 9.68 B-6
042215,000219: 05,3427 10372 DEC .647625 E-4 B+12
042216,000220: 05,3430 77126 DEC -27228. B-20
042217,000221: 05,3431 76261 DEC -.206476 B-2
042218,000222:
042219,000223: 05,3432 00767 SLOPEVAL DEC 1.96307 B-6
042220,000224: 05,3433 15624 DEC 27.5774 B-6
042221,000225: 05,3434 03054 DEC 2.3548 E-5 B+12
042222,000226: 05,3435 04532 DEC 2.1777 E-9 B+26
042223,000227: 05,3436 10433 DEC 1.044 E-3 B+8
042224,000228: 05,3437 00000 DEC 0 B-14
042225,000229: 05,3440 22070 DEC 2.21068 E-3 B+8
042226,000230: 05,3441 03204 DEC 1.5166 E-9 B+26
042227,000231: 05,3442 77266 DEC -1.284 B-6
042228,000232: 05,3443 02476 DEC 2. E-5 B+12
042229,000233:
042230,000234: 05,3444 70364 NEGBPW DEC -15402.17 B-16
042231,000235: 05,3445 75420 DXITFIX DEC* -1.88275 E-5 B+12*
End of include-file TVCMASSPROP.agc. Parent file is MAIN.agc