Source Code
042419,000001: # Copyright: Public domain.
042420,000002: # Filename: TVCRESTARTS.agc
042421,000003: # Purpose: Part of the source code for Colossus 2A, AKA Comanche 055.
042422,000004: # It is part of the source code for the Command Module's (CM)
042423,000005: # Apollo Guidance Computer (AGC), for Apollo 11.
042424,000006: # Assembler: yaYUL
042425,000007: # Contact: Ron Burkey <info@sandroid.org>.
042426,000008: # Website: www.ibiblio.org/apollo.
042427,000009: # Pages: 956-960
042428,000010: # Mod history: 2009-05-13 RSB Adapted from the Colossus249/ file of the
042429,000011: # same name, using Comanche055 page images.
042430,000012: # 2009-05-20 RSB Corrections: TCF -> BZF in one place.
042431,000013: # 2009-05-21 RSB In PHSCHK2, CS TVCPHASE corrected to
042432,000014: # CCS TVCPHASE and CCS 4 corrected to CCS A.
042433,000015: # Page 924 corrected to 961. CORCOPY +2
042434,000016: # corrected to CORCOPY +1.
042435,000017: # 2010-08-24 JL Fixed page 958 number. Fixed some indentation.
042436,000018:
042437,000019: # This source code has been transcribed or otherwise adapted from digitized
042438,000020: # images of a hardcopy from the MIT Museum. The digitization was performed
042439,000021: # by Paul Fjeld, and arranged for by Deborah Douglas of the Museum. Many
042440,000022: # thanks to both. The images (with suitable reduction in storage size and
042441,000023: # consequent reduction in image quality as well) are available online at
042442,000024: # www.ibiblio.org/apollo. If for some reason you find that the images are
042443,000025: # illegible, contact me at info@sandroid.org about getting access to the
042444,000026: # (much) higher-quality images which Paul actually created.
042445,000027:
042446,000028: # Notations on the hardcopy document read, in part:
042447,000029:
042448,000030: # Assemble revision 055 of AGC program Comanche by NASA
042449,000031: # 2021113-051. 10:28 APR. 1, 1969
042450,000032:
042451,000033: # This AGC program shall also be referred to as
042452,000034: # Colossus 2A
042453,000035:
042454,000036: # Page 956
042455,000037: # NAME....TVCRESTART PACKAGE, CONSISTING OF REDOTVC, ENABL1, 2, CMDSOUT, PHSCHK2, ETC.
042456,000038: # LOG SECTION....TVCRESTARTS SUBROUTINE....DAPCSM
042457,000039: # MODIFIED BY SCHLUNDT 21 OCTOBER 1968
042458,000040:
042459,000041: # FUNCTIONAL DESCRIPTION....
042460,000042:
042461,000043: # *RESTART-PROCESS THE TVC DAPS, INCLUDING PITCHDAP, YAWDAP,
042462,000044: # TVCEXECUTIVE, ROLLDAP, TVCINIT4, TVCDAPON, AND CSM/.M V46 SWTCHOVR.
042463,000045:
042464,000046: # *TVC RESTARTS DESERVE SPECIAL CONSIDERATION IN SEVERAL AREAS.
042465,000047: # RESTART DOWN-TIME IS IMPORTANT BECAUSE OF THE TRANSIENTS INTRODUCED
042466,000048: # BY THE THRUST VECTOR RETURN TO THE ACTUATOR MECHANICAL NULLS
042467,000049: # FOLLOWING TVC- AND OPTICS-ERROR-COUNTER-DISENABLES (CHANNEL 12).
042468,000050: # TVC USES A MIXTURE OF WAITLIST, T5, T6, AND JOB CALLS. THERE IS
042469,000051: # FILTER MEMORY (UP TO 6TH ORDER) TO BE PROTECTED IF WILD TRANSIENTS
042470,000052: # ARE TO BE AVOIDED. COUNTERS ARE INVOLVED FOR ONE-SHOT
042471,000053: # CORRECTIONS AND GAIN UPDATES. THE GIMBAL TRIM ESTIMATORS AND THE
042472,000054: # BODY AXIS ATTITUDE ERROR INTEGRATORS INVOLVE DIGITAL SUMMATION.
042473,000055: # DIGITAL DIFFERENTIATORS ARE INVOLVED IN THE BODY AXIS RATE ESTIMA-
042474,000056: # TIONS AND IN THE OUTPUTTING OF ACTUATOR COMMANDS. THERE IS AN
042475,000057: # OFFSET-TRACKER-FILTER TO PROTECT. ETC., ETC.
042476,000058:
042477,000059: # *THOSE QUANTITIES WHICH MUST BE PROTECTED ARE STORED IN TEMPORARY
042478,000060: # REGISTERS AS THEY ARE COMPUTED, FOR UPDATING THE REAL REGISTERS
042479,000061: # DURING COPYCYCLES.
042480,000062:
042481,000063: # *THE SEVERAL COPYCYCLES ARE EACH PROTECTED BY PHASE POINTS AT THEIR
042482,000064: # BEGINNING AND AT THEIR TERMINATION. THE PHASE POINTS ARE SIMPLY
042483,000065: # "INCR" INSTRUCTIONS, EITHER "INCR TVCEXPHS" FOR COPYCYCLES
042484,000066: # IN THE TVCEXECUTIVE, OR "INCR TVCPHASE" FOR THE PITCH AND YAW
042485,000067: # COPYCYCLES. INDEXING ON EACH OF THESE POINTERS THEN PERMITS A
042486,000068: # RETURN TO THE APPROPRIATE RESTART POINTS.
042487,000069:
042488,000070: # *IF A RESTART OCCURS DURING EITHER COPYCYCLE, THAT COPYCYCLE IS
042489,000071: # COMPLETED. THEN THE NORMAL TVCINIT4....DAPINIT....PITCHDAP STARTUP
042490,000072: # SEQUENCE IS CALLED UPON TO GET THINGS GOING AGAIN.
042491,000073:
042492,000074: # *TVC-ENABLE AND OPTICS-ERROR-COUNTER ENABLE MUST BE SET ASAP
042493,000075: # (ALLOWING FOR PROCEDURAL DELAYS). THEN THE ENGINES ARE COMMANDED
042494,000076: # TO THE P,YACTOFF TRIM VALUES. THE DAPS ARE THEN READY TO GO ON THE
042495,000077: # AIR, WITH THE REGULAR STARTUP SEQUENCE, EITHER AT MRCLEAN FOR A
042496,000078: # COMPLETE INITIALIZATION OR AT TVCINIT4 FOR A PARTIAL INITIALIZATION.
042497,000079:
042498,000080: # *FOR RESTARTS PRIOR TO THE SETTING OF THE T5 BITS AT DOTVCON THE
042499,000081: # PRE40.6 SECTION OF S40.6 TAKES CARE OF RE-ESTABLISHING TRIMS.
042500,000082:
042501,000083: # *IF A RESTART OCCURS DURING THE TVCEXEC....TVCEXFIN SEQUENCE THE
042502,000084: # COMPUTATIONS WILL BE COMPLETED, STARTING AT THE APPROPRIATE RESTART
042503,000085: # POINT, AFTER THE DAPS ARE READY TO GO ON THE AIR.
042504,000086:
042505,000087: # *IF A RESTART OCCURS PRIOR TO TVCINIT4 (TVCPHAS = -1) E.G. DURING
042506,000088: # THE EARLY DAP INITIALIZATION PHASE, THE DAP STARTUP SEQUENCE IS
042507,000089: # ENTERED AT MRCLEAN FOR A FULL INITIALIZATION.
042508,000090:
042509,000091: # *FOR RESTARTS DURING CSM/LM V46 SWITCH-VER, TVCPHASE IS SET TO -2.
042510,000092: # AND THE RESTART LOGIC GOES BACK TO REDO SWITCH-OVER (AFTER THE
042511,000093: # NORMAL DAP RESTART SEQUENCE IS FOLLOWED.)
042512,000094:
042513,000095: # *RESTARTS ARE NOT CRITICAL TO THE ROLL DAP PERFORMANCES HENCE THE
042514,000096: # ROLL DAP IS MERELY RESTARTED.
042515,000097:
042516,000098: # *RESTARTS DURING A STROKE TEST (STROKER IS NON-ZERO) WILL CAUSE THE
042517,000099: # Page 957
042518,000100: # STROKE TEST TO BE TERMINATED. A NEW V68 ENTRY WILL BE REQUIRED
042519,000101: # TO GET IT GOING AGAIN (NO AUTOMATIC RESTART).
042520,000102: #
042521,000103: # *REDOTVC IS REACHED FOLLOWING ANY RESTART WHICH FINDS THE T5 BITS
042522,000104: # (BITS 15,14 OF FLAGWRD6) SET FOR TVC. DOTVCON TVCPHASE = -1
042523,000105: # AND TVC EXPHS = 0 JUST BEFORE SETTING THESE BITS, JUST BEFORE
042524,000106: # MAKING THE T5 CALL TO TVCDAPON. ON A NORMAL SHUTDOWN DOTVCRCS
042525,000107: # CALLS RCSDAPON, WHICH RESETS THE T5 BIT FOR RCS
042526,000108:
042527,000109: # CALLING SEQUENCE....T5, IN PARTICULAR BY ELRSKIP OF FRESH START/RESTART
042528,000110:
042529,000111: # NORMAL EXIT MODES....RESUME, NOQRSM, POSTJUMP (TO TVCINIT4 OR MRCLEAN)
042530,000112:
042531,000113: # ALARM OR ABORT EXIT MODES....NONE
042532,000114:
042533,000115: # SUBROUTINES CALLED....
042534,000116:
042535,000117: # *PCOPY+1, YCOPY+1 (PITCH AND YAW COPYCYCLES)
042536,000118: # *ENABLE1,2, CMDSOUT (RE-ESTABLISH ACTUATOR TRIMS)
042537,000119: # *MRCLEAN OR TVCINIT4 (TVCDAP INITIALIZATIONS)
042538,000120: # *SWITCHOVR +5 (CSM/LM V46 SWITCH-OVER)
042539,000121: # *EXRSTRT AND TVCEXECUTIVE PHASE POINTS 1 THRU 6
042540,000122: # *WAITLIST, IBNKCALL, POSTJUMP, ISWCALL
042541,000123:
042542,000124: # OTHER INTERFACES....DOTVCON AND RCSDAPON (T5 BITS), ELRSKIP (CALLS IT)
042543,000125:
042544,000126: # ERASABLE ININTIALIZATION REQUIRED....
042545,000127:
042546,000128: # *T5 BITS (1,0), TVCPHASE (-2,-1,0,1,2,3), TVCEXPHS (1 THRU 6)
042547,000129: # *TVC DAP VARIABLES
042548,000130: # *OPERATIONS PERFORMED BY REDOTVC ARE BASED ON THE ASSUMPTION THAT
042549,000131: # THE TVC DAPS ARE RUNNING NORMALLY
042550,000132:
042551,000133: # OUTPUT....
042552,000134:
042553,000135: # *PITCH AND YAW TVC DAP COPYCYCLES COMPLETED IF INTERRUPTED
042554,000136: # *TVCEXECUTIVE COMPLETED IF INTERRUPTED
042555,000137: # *STROKE TEST TERMINATED IF INTERRUPTED
042556,000138: # *CSM/LM V46 SWITCH-OVER REPEATED IF INTERRUPTED
042557,000139: # *ACTUATOR TRIMS RE-ESTABLISHED (ACTUATORS BACK ON THE AIR)
042558,000140: # *TVC DAP INITIALIZATION AS REQUIRED
042559,000141: # *ALL TVC DAP OPERATIONS ON THE AIR
042560,000142:
042561,000143: # DEBRIS....TVC TEMPORARIES IN EBANK6
042562,000144:
042563,000145: # Page 958
042564,000146:
042565,000147: 16,3140 BANK 16
042566,000148: 16,2000 SETLOC DAPROLL
042567,000149: 16,2000 BANK
042568,000150: 16,3140 E6,1644 EBANK= TVCPHASE
042569,000151: 16,3140 COUNT* $$/RSRT
042570,000152:
042571,000153: 16,3140 22016 REDOTVC LXCH BANKRUPT # TVC RESTART PACKAGE
042572,000154: 16,3141 00006 EXTEND
042573,000155: 16,3142 22012 QXCH QRUPT # ("TCR" IN "FINCOPY")
042574,000156:
042575,000157: 16,3143 11651 EXECPHS CCS TVCEXPHS # CHECK TVCEXECUTIVE PHASE
042576,000158: 16,3144 13146 TCF +2 # MUST RESTART TVCEXECUTIVE
042577,000159: 16,3145 13152 TCF TVCDAPHS # NO NEED TO RESTART TVCEXECUTIVE
042578,000160:
042579,000161: 16,3146 34334 CAF NINE # 9CS DELAY TO FORCE EXRSTRT TO OCCUR
042580,000162: 16,3147 05245 TC WAITLIST # BEFORE PITCHDAP, AFTER CMDSOUT
042581,000163: 16,3150 E6,1651 EBANK= TVCEXPHS
042582,000164: 16,3150 03253 34066 2CADR EXRSTRT
042583,000165:
042584,000166: 16,3152 47700 TVCDAPHS CS OCT37776 # CHECK BITS 15 AND 1 OF TVCPHASE TO SEE
042585,000167: 16,3153 71644 MASK TVCPHASE # DAP RESTART LOCATION (-1,1,2,3)
042586,000168: 16,3154 10000 CCS A
042587,000169: 16,3155 13240 TCF FINCOPY # FINISH THE COPYCYCLE FIRST
042588,000170: 16,3156 13163 TCF ENABL1 # JUST PREPARE THE OUTCOUNTERS AND GO
042589,000171:
042590,000172: 16,3157 41644 CS TVCPHASE # TEST FOR TVCPHASE = -2
042591,000173: 16,3160 75016 MASK BIT2 # (THIS INDICATES RESTART OCCURRED
042592,000174: 16,3161 00006 EXTEND # DURING CSM/LM V46 SWITCH-OVER)
042593,000175: 16,3162 13244 BZF TRIM/CMD # NO. TVCPHASE = -1. RSTRT WAS IN TVCINIT
042594,000176:
042595,000177: 16,3163 35010 ENABL1 CAF BIT8 # TVC ENABLE, FOLLOWED BY 40 MS (MIN) WAIT
042596,000178: 16,3164 65005 AD BIT11 # SET BIT FOR OPTICS-DAC-ENABLE ALSO
042597,000179: 16,3165 00006 EXTEND # (ENABL1 ENTERED FROM TVCDAPHS / FINCOPY)
042598,000180: 16,3166 05012 WOR CHAN12
042599,000181: 16,3167 33257 CAF TVCADDR # WAIT, CALLING ENABL2 (BBCON THERE)
042600,000182: 16,3170 55312 TS T5LOC
042601,000183: 16,3171 33263 CAF TVCADDR +4 # 60 MS (TVCEXADR)
042602,000184: 16,3172 54030 TS TIME5
042603,000185:
042604,000186: 16,3173 15333 TCF RESUME
042605,000187:
042606,000188: 16,3174 22016 ENABL2 LXCH BANKRUPT # CONTINUE PREPARATION OF OUTCOUNTERS
042607,000189:
042608,000190: 16,3175 35016 CAF BIT2 # OPTICS ERROR CNTR ENABLE, 4MS MIN WAIT
042609,000191: 16,3176 00006 EXTEND
042610,000192: 16,3177 05012 WOR CHAN12
042611,000193: # Page 959
042612,000194: 16,3200 33261 CAF TVCADDR +2 # WAIT, CALLING CMDSOUT (BBCON THERE)
042613,000195: 16,3201 55312 TS T5LOC
042614,000196: 16,3202 37700 CAF OCT37776 # 20MS
042615,000197: 16,3203 54030 TS TIME5
042616,000198:
042617,000199: 16,3204 15335 TCF NOQRSM
042618,000200:
042619,000201: 16,3205 22016 CMDSOUT LXCH BANKRUPT # CONTNUE PREPARATION OF OUTCOUNTERS
042620,000202: 16,3206 00006 EXTEND
042621,000203: 16,3207 22012 QXCH QRUPT
042622,000204:
042623,000205: 16,3210 45021 CS ZERO # MOST RECENT ACTUATOR COMMANDS
042624,000206: 16,3211 61623 AD PCMD # (AVOID +0)
042625,000207: 16,3212 54054 TS TVCPITCH
042626,000208: 16,3213 45021 CS ZERO
042627,000209: 16,3214 61624 AD YCMD
042628,000210: 16,3215 54053 TS TVCYAW
042629,000211:
042630,000212: 16,3216 35062 CAF PRIO6 # RELEASE THE COUNTERS (BITS 11,12)
042631,000213: 16,3217 00006 EXTEND
042632,000214: 16,3220 05014 WOR CHAN14
042633,000215:
042634,000216: 16,3221 11644 PHSCHK2 CCS TVCPHASE # CHECK TVCPHASE AGAIN
042635,000217: 16,3222 13232 TCF CHKSTRK
042636,000218: 16,3223 13232 TCF CHKSTRK
042637,000219: 16,3224 10000 CCS A # A CONTAINS THE DIMINISHED ABSOLUTE OF
042638,000220: 16,3225 03230 TC +3 # TVCPHASE (-2 BECOMES +1. -1 BECOMES +0)
042639,000221:
042640,000222: 16,3226 04701 TC POSTJUMP # REPEAT TVC INITIALIZATION
042641,000223: 16,3227 36152 CADR MRCLEAN # (DO NOT RETURN)
042642,000224:
042643,000225: 16,3230 04740 +3 TC IBNKCALL # REPEAT CSM/LM V46 SWITCH-OVER
042644,000226: 16,3231 36361 CADR SWICHOVR +5 # (RETURN TO CHECK FOR STROKE TEST)
042645,000227:
042646,000228: 16,3232 11574 CHKSTRK CCS STROKER # CHECK FOR STROKE TEST IN PROGRESS
042647,000229: 16,3233 13250 TCF TSTINITJ # YES, KILL IT
042648,000230: 16,3234 13236 TCF +2 # NO, PROCEED
042649,000231: 16,3235 13250 TCF TSTINITJ # YES, KILL IT
042650,000232:
042651,000233: 16,3236 04701 +4 TC POSTJUMP # IF POSITIVE OR ZERO, RESTART AT
042652,000234: 16,3237 36324 CADR TVCINIT4 # TVCINIT4 (ZEROS TVCPHASE, AND
042653,000235: # CALLS TVC DAPS VIA DAPINIT)
042654,000236: 16,3240 51644 FINCOPY INDEX TVCPHASE # PICK UP THE APPROPRIATE COPYCYCLE
042655,000237: 16,3241 33257 CAF TVCCADR
042656,000238: 16,3242 04744 TCR ISWCALL # RE-ENTER THE COPYCYCLE, RETURN AT END
042657,000239: 16,3243 13163 TCF ENABL1 # NOW PREPARE THE OUTCOUNTERS
042658,000240:
042659,000241: 16,3244 00006 TRIM/CMD EXTEND # TVCDAPON INITIALIZATION NOT COMPLETED,
042660,000242: # Page 960
042661,000243: 16,3245 31424 DCA PACTOFF # EG. P,YCMD MAY NOT BE SET. SET...
042662,000244: 16,3246 53624 DXCH PCMD
042663,000245: 16,3247 13163 TCF ENABL1 # NOW PREPARE THE OUTCOUNTERS
042664,000246:
042665,000247: 16,3250 35021 TSTINITJ CAF ZERO # DISABLE STROKE TEST (-0 SHOWS PRIOR V68)
042666,000248: 16,3251 55574 TS STROKER # (+0 MEANS NEW V68 REQUIRED FOR STARTUP)
042667,000249:
042668,000250: 16,3252 13236 TCF CHKSTRK +4
042669,000251:
042670,000252: 16,3253 51651 EXRSTRT INDEX TVCEXPHS # TVCEXECUTIVE RESTARTS....GO TO
042671,000253: 16,3254 33263 CAF TVCEXADR # APPROPRIATE RESTART POINT
042672,000254: 16,3255 50000 INDEX A
042673,000255: 16,3256 10000 TCF 0
042674,000256:
042675,000257: # Page 961
042676,000258: # TVC RESTART TABLES.... ORDER IS REQUIRED. HI-ORDER WORDS ONLY, OF 2CADRS, SINCE BBCON IS ALREADY THERE.
042677,000259:
042678,000260: 16,3257 16,3257 TVCADDR = TVCCADR # TABLE OF CADRS, UNUSED LOCS FOR GENADRS
042679,000261: 16,3257 03174 TVCCADR GENADR ENABL2 # (FOR T5 CALL, UNUSED TABLE LOC)
042680,000262: 16,3260 40675 +1 CADR PCOPY +1 # PITCH COPYCYCLE
042681,000263: 16,3261 03205 +2 GENADR CMDSOUT # (FOR T5 CALL, UNUSED TABLE LOC)
042682,000264: 16,3262 41051 +3 CADR YCOPY +1 # YAW COPYCYCLE
042683,000265: 16,3263 37772 TVCEXADR OCT 37772 # (UNUSED TABLE LOC, FILL WITH 60MS, T5)
042684,000266: 16,3264 03003 +1 GENADR EXECCOPY +1 # TVCEXECUTIVE RESTART POINTS (ORDERED)
042685,000267: 16,3265 03011 +2 GENADR 1SHOTCHK
042686,000268: 16,3266 03040 +3 GENADR TEMPSET
042687,000269: 16,3267 03043 +4 GENADR CORSETUP
042688,000270: 16,3270 03121 +5 GENADR CORCOPY +1
042689,000271: 16,3271 03132 +6 GENADR CNTRCOPY
End of include-file TVCRESTARTS.agc. Parent file is MAIN.agc