Source Code

042465,000001: # Copyright: Public domain. 042466,000002: # Filename: TVCRESTARTS.agc 042467,000003: # Purpose: Part of the source code for Colossus 2A, AKA Comanche 055. 042468,000004: # It is part of the source code for the Command Module's (CM) 042469,000005: # Apollo Guidance Computer (AGC), for Apollo 11. 042470,000006: # Assembler: yaYUL 042471,000007: # Contact: Ron Burkey <info@sandroid.org>. 042472,000008: # Website: www.ibiblio.org/apollo. 042473,000009: # Pages: 956-960 042474,000010: # Mod history: 2009-05-13 RSB Adapted from the Colossus249/ file of the 042475,000011: # same name, using Comanche055 page images. 042476,000012: # 2009-05-20 RSB Corrections: TCF -> BZF in one place. 042477,000013: # 2009-05-21 RSB In PHSCHK2, CS TVCPHASE corrected to 042478,000014: # CCS TVCPHASE and CCS 4 corrected to CCS A. 042479,000015: # Page 924 corrected to 961. CORCOPY +2 042480,000016: # corrected to CORCOPY +1. 042481,000017: 042482,000018: # This source code has been transcribed or otherwise adapted from digitized 042483,000019: # images of a hardcopy from the MIT Museum. The digitization was performed 042484,000020: # by Paul Fjeld, and arranged for by Deborah Douglas of the Museum. Many 042485,000021: # thanks to both. The images (with suitable reduction in storage size and 042486,000022: # consequent reduction in image quality as well) are available online at 042487,000023: # www.ibiblio.org/apollo. If for some reason you find that the images are 042488,000024: # illegible, contact me at info@sandroid.org about getting access to the 042489,000025: # (much) higher-quality images which Paul actually created. 042490,000026: 042491,000027: # Notations on the hardcopy document read, in part: 042492,000028: 042493,000029: # Assemble revision 055 of AGC program Comanche by NASA 042494,000030: # 2021113-051. 10:28 APR. 1, 1969 042495,000031: 042496,000032: # This AGC program shall also be referred to as 042497,000033: # Colossus 2A 042498,000034: 042499,000035: # Page 956 042500,000036: # NAME....TVCRESTART PACKAGE, CONSISTING OF REDOTVC, ENABL1, 2, CMDSOUT, PHSCHK2, ETC. 042501,000037: # LOG SECTION....TVCRESTARTS SUBROUTINE....DAPCSM 042502,000038: # MODIFIED BY SCHLUNDT 21 OCTOBER 1968 042503,000039: 042504,000040: # FUNCTIONAL DESCRIPTION.... 042505,000041: 042506,000042: # *RESTART-PROCESS THE TVC DAPS, INCLUDING PITCHDAP, YAWDAP, 042507,000043: # TVCEXECUTIVE, ROLLDAP, TVCINIT4, TVCDAPON, AND CSM/.M V46 SWTCHOVR. 042508,000044: 042509,000045: # *TVC RESTARTS DESERVE SPECIAL CONSIDERATION IN SEVERAL AREAS. 042510,000046: # RESTART DOWN-TIME IS IMPORTANT BECAUSE OF THE TRANSIENTS INTRODUCED 042511,000047: # BY THE THRUST VECTOR RETURN TO THE ACTUATOR MECHANICAL NULLS 042512,000048: # FOLLOWING TVC- AND OPTICS-ERROR-COUNTER-DISENABLES (CHANNEL 12). 042513,000049: # TVC USES A MIXTURE OF WAITLIST, T5, T6, AND JOB CALLS. THERE IS 042514,000050: # FILTER MEMORY (UP TO 6TH ORDER) TO BE PROTECTED IF WILD TRANSIENTS 042515,000051: # ARE TO BE AVOIDED. COUNTERS ARE INVOLVED FOR ONE-SHOT 042516,000052: # CORRECTIONS AND GAIN UPDATES. THE GIMBAL TRIM ESTIMATORS AND THE 042517,000053: # BODY AXIS ATTITUDE ERROR INTEGRATORS INVOLVE DIGITAL SUMMATION. 042518,000054: # DIGITAL DIFFERENTIATORS ARE INVOLVED IN THE BODY AXIS RATE ESTIMA- 042519,000055: # TIONS AND IN THE OUTPUTTING OF ACTUATOR COMMANDS. THERE IS AN 042520,000056: # OFFSET-TRACKER-FILTER TO PROTECT. ETC., ETC. 042521,000057: 042522,000058: # *THOSE QUANTITIES WHICH MUST BE PROTECTED ARE STORED IN TEMPORARY 042523,000059: # REGISTERS AS THEY ARE COMPUTED, FOR UPDATING THE REAL REGISTERS 042524,000060: # DURING COPYCYCLES. 042525,000061: 042526,000062: # *THE SEVERAL COPYCYCLES ARE EACH PROTECTED BY PHASE POINTS AT THEIR 042527,000063: # BEGINNING AND AT THEIR TERMINATION. THE PHASE POINTS ARE SIMPLY 042528,000064: # "INCR" INSTRUCTIONS, EITHER "INCR TVCEXPHS" FOR COPYCYCLES 042529,000065: # IN THE TVCEXECUTIVE, OR "INCR TVCPHASE" FOR THE PITCH AND YAW 042530,000066: # COPYCYCLES. INDEXING ON EACH OF THESE POINTERS THEN PERMITS A 042531,000067: # RETURN TO THE APPROPRIATE RESTART POINTS. 042532,000068: 042533,000069: # *IF A RESTART OCCURS DURING EITHER COPYCYCLE, THAT COPYCYCLE IS 042534,000070: # COMPLETED. THEN THE NORMAL TVCINIT4....DAPINIT....PITCHDAP STARTUP 042535,000071: # SEQUENCE IS CALLED UPON TO GET THINGS GOING AGAIN. 042536,000072: 042537,000073: # *TVC-ENABLE AND OPTICS-ERROR-COUNTER ENABLE MUST BE SET ASAP 042538,000074: # (ALLOWING FOR PROCEDURAL DELAYS). THEN THE ENGINES ARE COMMANDED 042539,000075: # TO THE P,YACTOFF TRIM VALUES. THE DAPS ARE THEN READY TO GO ON THE 042540,000076: # AIR, WITH THE REGULAR STARTUP SEQUENCE, EITHER AT MRCLEAN FOR A 042541,000077: # COMPLETE INITIALIZATION OR AT TVCINIT4 FOR A PARTIAL INITIALIZATION. 042542,000078: 042543,000079: # *FOR RESTARTS PRIOR TO THE SETTING OF THE T5 BITS AT DOTVCON THE 042544,000080: # PRE40.6 SECTION OF S40.6 TAKES CARE OF RE-ESTABLISHING TRIMS. 042545,000081: 042546,000082: # *IF A RESTART OCCURS DURING THE TVCEXEC....TVCEXFIN SEQUENCE THE 042547,000083: # COMPUTATIONS WILL BE COMPLETED, STARTING AT THE APPROPRIATE RESTART 042548,000084: # POINT, AFTER THE DAPS ARE READY TO GO ON THE AIR. 042549,000085: 042550,000086: # *IF A RESTART OCCURS PRIOR TO TVCINIT4 (TVCPHAS = -1) E.G. DURING 042551,000087: # THE EARLY DAP INITIALIZATION PHASE, THE DAP STARTUP SEQUENCE IS 042552,000088: # ENTERED AT MRCLEAN FOR A FULL INITIALIZATION. 042553,000089: 042554,000090: # *FOR RESTARTS DURING CSM/LM V46 SWITCH-VER, TVCPHASE IS SET TO -2. 042555,000091: # AND THE RESTART LOGIC GOES BACK TO REDO SWITCH-OVER (AFTER THE 042556,000092: # NORMAL DAP RESTART SEQUENCE IS FOLLOWED.) 042557,000093: 042558,000094: # *RESTARTS ARE NOT CRITICAL TO THE ROLL DAP PERFORMANCES HENCE THE 042559,000095: # ROLL DAP IS MERELY RESTARTED. 042560,000096: 042561,000097: # *RESTARTS DURING A STROKE TEST (STROKER IS NON-ZERO) WILL CAUSE THE 042562,000098: # Page 957 042563,000099: # STROKE TEST TO BE TERMINATED. A NEW V68 ENTRY WILL BE REQUIRED 042564,000100: # TO GET IT GOING AGAIN (NO AUTOMATIC RESTART). 042565,000101: # 042566,000102: # *REDOTVC IS REACHED FOLLOWING ANY RESTART WHICH FINDS THE T5 BITS 042567,000103: # (BITS 15,14 OF FLAGWRD6) SET FOR TVC. DOTVCON TVCPHASE = -1 042568,000104: # AND TVC EXPHS = 0 JUST BEFORE SETTING THESE BITS, JUST BEFORE 042569,000105: # MAKING THE T5 CALL TO TVCDAPON. ON A NORMAL SHUTDOWN DOTVCRCS 042570,000106: # CALLS RCSDAPON, WHICH RESETS THE T5 BIT FOR RCS 042571,000107: 042572,000108: # CALLING SEQUENCE....T5, IN PARTICULAR BY ELRSKIP OF FRESH START/RESTART 042573,000109: 042574,000110: # NORMAL EXIT MODES....RESUME, NOQRSM, POSTJUMP (TO TVCINIT4 OR MRCLEAN) 042575,000111: 042576,000112: # ALARM OR ABORT EXIT MODES....NONE 042577,000113: 042578,000114: # SUBROUTINES CALLED.... 042579,000115: 042580,000116: # *PCOPY+1, YCOPY+1 (PITCH AND YAW COPYCYCLES) 042581,000117: # *ENABLE1,2, CMDSOUT (RE-ESTABLISH ACTUATOR TRIMS) 042582,000118: # *MRCLEAN OR TVCINIT4 (TVCDAP INITIALIZATIONS) 042583,000119: # *SWITCHOVR +5 (CSM/LM V46 SWITCH-OVER) 042584,000120: # *EXRSTRT AND TVCEXECUTIVE PHASE POINTS 1 THRU 6 042585,000121: # *WAITLIST, IBNKCALL, POSTJUMP, ISWCALL 042586,000122: 042587,000123: # OTHER INTERFACES....DOTVCON AND RCSDAPON (T5 BITS), ELRSKIP (CALLS IT) 042588,000124: 042589,000125: # ERASABLE ININTIALIZATION REQUIRED.... 042590,000126: 042591,000127: # *T5 BITS (1,0), TVCPHASE (-2,-1,0,1,2,3), TVCEXPHS (1 THRU 6) 042592,000128: # *TVC DAP VARIABLES 042593,000129: # *OPERATIONS PERFORMED BY REDOTVC ARE BASED ON THE ASSUMPTION THAT 042594,000130: # THE TVC DAPS ARE RUNNING NORMALLY 042595,000131: 042596,000132: # OUTPUT.... 042597,000133: 042598,000134: # *PITCH AND YAW TVC DAP COPYCYCLES COMPLETED IF INTERRUPTED 042599,000135: # *TVCEXECUTIVE COMPLETED IF INTERRUPTED 042600,000136: # *STROKE TEST TERMINATED IF INTERRUPTED 042601,000137: # *CSM/LM V46 SWITCH-OVER REPEATED IF INTERRUPTED 042602,000138: # *ACTUATOR TRIMS RE-ESTABLISHED (ACTUATORS BACK ON THE AIR) 042603,000139: # *TVC DAP INITIALIZATION AS REQUIRED 042604,000140: # *ALL TVC DAP OPERATIONS ON THE AIR 042605,000141: 042606,000142: # DEBRIS....TVC TEMPORARIES IN EBANK6 042607,000143: 042608,000144: # Page 958 042609,000145: 042610,000146: 16,3140 BANK 16 042611,000147: 16,2000 SETLOC DAPROLL 042612,000148: 16,2000 BANK 042613,000149: 16,3140 E6,1644 EBANK= TVCPHASE 042614,000150: 16,3140 COUNT* $$/RSRT 042615,000151: 042616,000152: 16,3140 22016 REDOTVC LXCH BANKRUPT # TVC RESTART PACKAGE 042617,000153: 16,3141 00006 EXTEND 042618,000154: 16,3142 22012 QXCH QRUPT # ("TCR" IN "FINCOPY") 042619,000155: 042620,000156: 16,3143 11651 EXECPHS CCS TVCEXPHS # CHECK TVCEXECUTIVE PHASE 042621,000157: 16,3144 13146 TCF +2 # MUST RESTART TVCEXECUTIVE 042622,000158: 16,3145 13152 TCF TVCDAPHS # NO NEED TO RESTART TVCEXECUTIVE 042623,000159: 042624,000160: 16,3146 34334 CAF NINE # 9CS DELAY TO FORCE EXRSTRT TO OCCUR 042625,000161: 16,3147 05245 TC WAITLIST # BEFORE PITCHDAP, AFTER CMDSOUT 042626,000162: 16,3150 E6,1651 EBANK= TVCEXPHS 042627,000163: 16,3150 03253 34066 2CADR EXRSTRT 042628,000164: 042629,000165: 16,3152 47700 TVCDAPHS CS OCT37776 # CHECK BITS 15 AND 1 OF TVCPHASE TO SEE 042630,000166: 16,3153 71644 MASK TVCPHASE # DAP RESTART LOCATION (-1,1,2,3) 042631,000167: 16,3154 10000 CCS A 042632,000168: 16,3155 13240 TCF FINCOPY # FINISH THE COPYCYCLE FIRST 042633,000169: 16,3156 13163 TCF ENABL1 # JUST PREPARE THE OUTCOUNTERS AND GO 042634,000170: 042635,000171: 16,3157 41644 CS TVCPHASE # TEST FOR TVCPHASE = -2 042636,000172: 16,3160 75016 MASK BIT2 # (THIS INDICATES RESTART OCCURRED 042637,000173: 16,3161 00006 EXTEND # DURING CSM/LM V46 SWITCH-OVER) 042638,000174: 16,3162 13244 BZF TRIM/CMD # NO. TVCPHASE = -1. RSTRT WAS IN TVCINIT 042639,000175: 042640,000176: 16,3163 35010 ENABL1 CAF BIT8 # TVC ENABLE, FOLLOWED BY 40 MS (MIN) WAIT 042641,000177: 16,3164 65005 AD BIT11 # SET BIT FOR OPTICS-DAC-ENABLE ALSO 042642,000178: 16,3165 00006 EXTEND # (ENABL1 ENTERED FROM TVCDAPHS / FINCOPY) 042643,000179: 16,3166 05012 WOR CHAN12 042644,000180: 16,3167 33257 CAF TVCADDR # WAIT, CALLING ENABL2 (BBCON THERE) 042645,000181: 16,3170 55312 TS T5LOC 042646,000182: 16,3171 33263 CAF TVCADDR +4 # 60 MS (TVCEXADR) 042647,000183: 16,3172 54030 TS TIME5 042648,000184: 042649,000185: 16,3173 15333 TCF RESUME 042650,000186: 042651,000187: 16,3174 22016 ENABL2 LXCH BANKRUPT # CONTINUE PREPARATION OF OUTCOUNTERS 042652,000188: 042653,000189: 16,3175 35016 CAF BIT2 # OPTICS ERROR CNTR ENABLE, 4MS MIN WAIT 042654,000190: 16,3176 00006 EXTEND 042655,000191: 16,3177 05012 WOR CHAN12 042656,000192: # Page 959 042657,000193: 16,3200 33261 CAF TVCADDR +2 # WAIT, CALLING CMDSOUT (BBCON THERE) 042658,000194: 16,3201 55312 TS T5LOC 042659,000195: 16,3202 37700 CAF OCT37776 # 20MS 042660,000196: 16,3203 54030 TS TIME5 042661,000197: 042662,000198: 16,3204 15335 TCF NOQRSM 042663,000199: 042664,000200: 16,3205 22016 CMDSOUT LXCH BANKRUPT # CONTNUE PREPARATION OF OUTCOUNTERS 042665,000201: 16,3206 00006 EXTEND 042666,000202: 16,3207 22012 QXCH QRUPT 042667,000203: 042668,000204: 16,3210 45021 CS ZERO # MOST RECENT ACTUATOR COMMANDS 042669,000205: 16,3211 61623 AD PCMD # (AVOID +0) 042670,000206: 16,3212 54054 TS TVCPITCH 042671,000207: 16,3213 45021 CS ZERO 042672,000208: 16,3214 61624 AD YCMD 042673,000209: 16,3215 54053 TS TVCYAW 042674,000210: 042675,000211: 16,3216 35062 CAF PRIO6 # RELEASE THE COUNTERS (BITS 11,12) 042676,000212: 16,3217 00006 EXTEND 042677,000213: 16,3220 05014 WOR CHAN14 042678,000214: 042679,000215: 16,3221 11644 PHSCHK2 CCS TVCPHASE # CHECK TVCPHASE AGAIN 042680,000216: 16,3222 13232 TCF CHKSTRK 042681,000217: 16,3223 13232 TCF CHKSTRK 042682,000218: 16,3224 10000 CCS A # A CONTAINS THE DIMINISHED ABSOLUTE OF 042683,000219: 16,3225 03230 TC +3 # TVCPHASE (-2 BECOMES +1. -1 BECOMES +0) 042684,000220: 042685,000221: 16,3226 04701 TC POSTJUMP # REPEAT TVC INITIALIZATION 042686,000222: 16,3227 36152 CADR MRCLEAN # (DO NOT RETURN) 042687,000223: 042688,000224: 16,3230 04740 +3 TC IBNKCALL # REPEAT CSM/LM V46 SWITCH-OVER 042689,000225: 16,3231 36361 CADR SWICHOVR +5 # (RETURN TO CHECK FOR STROKE TEST) 042690,000226: 042691,000227: 16,3232 11574 CHKSTRK CCS STROKER # CHECK FOR STROKE TEST IN PROGRESS 042692,000228: 16,3233 13250 TCF TSTINITJ # YES, KILL IT 042693,000229: 16,3234 13236 TCF +2 # NO, PROCEED 042694,000230: 16,3235 13250 TCF TSTINITJ # YES, KILL IT 042695,000231: 042696,000232: 16,3236 04701 +4 TC POSTJUMP # IF POSITIVE OR ZERO, RESTART AT 042697,000233: 16,3237 36324 CADR TVCINIT4 # TVCINIT4 (ZEROS TVCPHASE, AND 042698,000234: # CALLS TVC DAPS VIA DAPINIT) 042699,000235: 16,3240 51644 FINCOPY INDEX TVCPHASE # PICK UP THE APPROPRIATE COPYCYCLE 042700,000236: 16,3241 33257 CAF TVCCADR 042701,000237: 16,3242 04744 TCR ISWCALL # RE-ENTER THE COPYCYCLE, RETURN AT END 042702,000238: 16,3243 13163 TCF ENABL1 # NOW PREPARE THE OUTCOUNTERS 042703,000239: 042704,000240: 16,3244 00006 TRIM/CMD EXTEND # TVCDAPON INITIALIZATION NOT COMPLETED, 042705,000241: # Page 960 042706,000242: 16,3245 31424 DCA PACTOFF # EG. P,YCMD MAY NOT BE SET. SET... 042707,000243: 16,3246 53624 DXCH PCMD 042708,000244: 16,3247 13163 TCF ENABL1 # NOW PREPARE THE OUTCOUNTERS 042709,000245: 042710,000246: 16,3250 35021 TSTINITJ CAF ZERO # DISABLE STROKE TEST (-0 SHOWS PRIOR V68) 042711,000247: 16,3251 55574 TS STROKER # (+0 MEANS NEW V68 REQUIRED FOR STARTUP) 042712,000248: 042713,000249: 16,3252 13236 TCF CHKSTRK +4 042714,000250: 042715,000251: 16,3253 51651 EXRSTRT INDEX TVCEXPHS # TVCEXECUTIVE RESTARTS....GO TO 042716,000252: 16,3254 33263 CAF TVCEXADR # APPROPRIATE RESTART POINT 042717,000253: 16,3255 50000 INDEX A 042718,000254: 16,3256 10000 TCF 0 042719,000255: 042720,000256: # Page 961 042721,000257: # TVC RESTART TABLES.... ORDER IS REQUIRED. HI-ORDER WORDS ONLY, OF 2CADRS, SINCE BBCON IS ALREADY THERE. 042722,000258: 042723,000259: 16,3257 16,3257 TVCADDR = TVCCADR # TABLE OF CADRS, UNUSED LOCS FOR GENADRS 042724,000260: 16,3257 03174 TVCCADR GENADR ENABL2 # (FOR T5 CALL, UNUSED TABLE LOC) 042725,000261: 16,3260 40675 +1 CADR PCOPY +1 # PITCH COPYCYCLE 042726,000262: 16,3261 03205 +2 GENADR CMDSOUT # (FOR T5 CALL, UNUSED TABLE LOC) 042727,000263: 16,3262 41051 +3 CADR YCOPY +1 # YAW COPYCYCLE 042728,000264: 16,3263 37772 TVCEXADR OCT 37772 # (UNUSED TABLE LOC, FILL WITH 60MS, T5) 042729,000265: 16,3264 03003 +1 GENADR EXECCOPY +1 # TVCEXECUTIVE RESTART POINTS (ORDERED) 042730,000266: 16,3265 03011 +2 GENADR 1SHOTCHK 042731,000267: 16,3266 03040 +3 GENADR TEMPSET 042732,000268: 16,3267 03043 +4 GENADR CORSETUP 042733,000269: 16,3270 03121 +5 GENADR CORCOPY +1 042734,000270: 16,3271 03132 +6 GENADR CNTRCOPY 042735,000271: 042736,000272: End of include-file TVCRESTARTS.agc. Parent file is MAIN.agc