Source Code
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These source-code files were transcribed from scans made from Don Eyles's personal
copy of BURST120 (SUNBURST 120). They were scanned at archive.org's Boston
facility, and the scanning was sponsored by Mike Stewart. The code was transcribed
from these scans by a team of volunteers who are referenced in the program
comments. Comments from the original source code are in ALL-CAPS, whereas
comments added later in transcription are in Mixed-Case. In some cases, where
similar code blocks exist in previously-transcribed AGC programs (primarily
Luminary 99, from Apollo 11) those code blocks were used as a starting point and
then corrected to agree with the BURST120 scans. The full scans are available
at the Virtual AGC
project's collection at archive.org, while more-convenient reduced-size (but reduced-quality)
images are available at
the main Virtual AGC website. Report any errors noted by creating an
issue report at the Virtual AGC
project's GitHub repository. Notations on the program listing read, in part:YUL SYSTEM FOR AGC: REVISION 0 OF PROGRAM BURST120 BY NASA 2021106-031 DEC 7, 1967 THIS LISTING IS A COPY OF A VERSION OF THE PROGRAM INTENDED FOR USE IN THE ON-BOARD PRIMARY GUIDANCE COMPUTER IN THE UNMANNED FLIGHT OF APOLLO LUNAR MODULE 1 --- THE AS206 MISSION.Note that the date is the date of the printout, not the date of the program revision. |
023823,000002: ## Copyright: Public domain.
023824,000003: ## Filename: RCS_FAILURE_MONITOR.agc
023825,000004: ## Purpose: A module for revision 0 of BURST120 (Sunburst). It
023826,000005: ## is part of the source code for the Lunar Module's
023827,000006: ## (LM) Apollo Guidance Computer (AGC) for Apollo 5.
023828,000007: ## Assembler: yaYUL
023829,000008: ## Contact: Ron Burkey <info@sandroid.org>.
023830,000009: ## Website: www.ibiblio.org/apollo/index.html
023831,000010: ## Mod history: 2016-09-30 RSB Created draft version.
023832,000011: ## 2016-10-30 HG Transcribed
023833,000012: ## 2016-10-31 RSB Typos.
023834,000013: ## 2016-12-06 RSB Comment proofing via octopus/ProoferComments
023835,000014: ## performed, and changes made.
023836,000015:
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Page 569 |
023838,000017: # PROGRAM DESCRIPTION DATE: 7 JAN 67
023839,000018:
023840,000019: # AUTHOR: J S MILLER (MIT INSTRUMENTATION LAB)
023841,000020:
023842,000021: # THIS ROUTINE IS ATTACHED TO T4RUPT, AND IS ENTERED EVERY 960 MS. ITS FUNCTION IS TO EXAMINE THE STATE
023843,000022: # OF THE LOW 8 BITS OF CHAN 32 TO SEE IF RCS-JET FAILURE BITS HAVE APPEARED OR DISAPPEARED. WHEN A STATE CHANGE
023844,000023: # IS DETECTED WHICH PERSISTS FOR 2 SAMPLES (TO FILTER OUT NOISY SIGNALS), AN LMP COMMAND IS SENT (BUT AT MOST ONE
023845,000024: # SUCH COMMAND PER SAMPLE) TO ISOLATE THE APPROPRIATE JET PAIR IF THE FAILURE SIGNAL HAS JUST APPEARED. IF, ON
023846,000025: # THE OTHER HAND, THE DISAPPEARANCE OF A FAIL-BIT IS DETECTED, THE EVENT IS PRESUMED TO BE THE RESULT OF THE
023847,000026: # GROUND HAVING SENT AN LMP COMMAND TO OPEN THE ISOLATION VALVE AND NO SUBSEQUENT FAILURE HAVING BEEN DETECTED BY
023848,000027: # THE DETECTION CIRCUITRY. IN EITHER CASE, THIS FAILURE-MONITOR PROGRAM RESPONDS BY UPDATING ITS RECORD OF THE
023849,000028: # STATE OF THE ISOLATION VALVES, AND ALSO THE PAIR OF WORDS IT MAINTAINS FOR USE BY THE DAP IN THE JET-POLICY
023850,000029: # SELECTION LOGIC.
023851,000030:
023852,000031: # A FEW WORDS ABOUT LMP-RESET COMMANDS: IN THE CYCLE IN WHICH A VALVE-CLOSURE COMMAND IS ISSUED, THE
023853,000032: # CORRESPONDING RESET COMMAND IS STORED IN THE REGISTER "JETRESET". THIS REGISTER IS EXAMINED AT THE BEGINNING OF
023854,000033: # EACH RCSMONIT CYCLE, AND IF A COMMAND IS WAITING, IT IS SENT IMMEDIATELY. THIS CAUSES RESET COMMANDS TO BE
023855,000034: # ISSUED AT ABOUT 960 MS AFTER THE SET COMMANDS. THIS TECHNIQUE ASSURES THAT NO MORE THAN ONE UN-RESET SET-
023856,000035: # COMMAND IS ON AT ANY TIME (ALTHOUGH GROUND ACTIONS WILL BE SUPERIMPOSED ON THIS, HOWEVER).
023857,000036:
023858,000037: # CALLING SEQUENCE:
023859,000038:
023860,000039: # TC RCSMONIT (IN INTERRUPT MODE, EVERY 960 MS.)
023861,000040: # EXIT:
023862,000041:
023863,000042: # TCF RCSMONEX (ALL PATHS EXIT VIA SUCH AN INSTRUCTION. RCSMONEX IS PRESENTLY EQUATED TO RESUME.)
023864,000043:
023865,000044: # ERASABLE INITIALIZATION REQUIRED:
023866,000045:
023867,000046: # VIA SLAP1: JETRESET = -0 (RESET-CMD BUFFER EMPTY)
023868,000047: # THISCH32 = +0 (NO FAILURES SENSED YET)
023869,000048: # CH5MASK, CH6MASK = +0 (0'S IF JETS ARE OK)
023870,000049: # LMPJFAIL = +0 (ISOLATION VALVES ALL OPEN)
023871,000050:
023872,000051: # OUTPUT:
023873,000052:
023874,000053: # CH5MASK & CH6MASK UPDATED (1'S WHERE JETS NOT TO BE USED)
023875,000054: # THISCH32 SET TO INVERTED LOW 8 BITS OF CHAN 32 (HIGH 7 = 0)
023876,000055: # LMPJFAIL UPDATED (1'S WHEN ISOLATION COMMANDS HAVE BEEN SENT)
023877,000056: # JETRESET CONTAINS RESET-COMMANDS TO BE SENT NEXT CYCLE THRU.
023878,000057:
023879,000058: # DEBRIS:
023880,000059:
023881,000060: # A, L, Q, & RCSMONT1 - 4 (PRESENTLY EQUATED TO RUPTREG1 - 4)
023882,000061:
023883,000062: # SUBROUTINES CALLED:
023884,000063:
023885,000064: # STORCOM (PART OF 1LMP ROUTINE)
023886,000065:
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023888,000067: 12,3166 BANK 12
023889,000068: 12,3166 0074 EBANK= STATE # NO SWITCHED ERASABLE USED.
023890,000069:
023891,000070: 12,3166 11162 RCSMONIT CCS JETRESET # CHECK WHETHER A RESET IS WAITING.
023892,000071: 12,3167 05063 TC STORCOM -1 # THERE IS A RESET TO SEND. DO IT.
023893,000072: 12,3170 47767 CS ZERO
023894,000073: 12,3171 55162 TS JETRESET # DEACTIVATE THE BUFFER.
023895,000074:
023896,000075: 12,3172 47767 AFTRESET CS ZERO
023897,000076: 12,3173 00006 EXTEND # PICK UP & INVERT INVERTED CHANNEL 32.
023898,000077: 12,3174 06032 RXOR 32
023899,000078: 12,3175 74564 MASK LOW8 # KEEP JET-FAIL BITS ONLY.
023900,000079: 12,3176 57163 XCH THISCH32
023901,000080: 12,3177 54071 TS RCSMONT2 # HANG ON TO PREVIOUS CH32 STATE.
023902,000081:
023903,000082: 12,3200 71163 MASK THISCH32 # - --
023904,000083: 12,3201 54001 TS L # FORM PTL + PTL.
023905,000084: 12,3202 40101 CS LMPJFAIL # ( P = PREVIOUS CH 32 STATE,
023906,000085: 12,3203 70001 MASK L # T = THIS CH 32 STATE,
023907,000086: 12,3204 54072 TS RCSMONT3 # L = LMP ISOLATION VALVE CMD STATE )
023908,000087: 12,3205 40071 CS RCSMONT2
023909,000088: 12,3206 54001 TS L
023910,000089: 12,3207 41163 CS THISCH32
023911,000090: 12,3210 70001 MASK L
023912,000091: 12,3211 70101 MASK LMPJFAIL
023913,000092: 12,3212 26072 ADS RCSMONT3 # BITS HERE NZ IF ACTION IS DUE NOW.
023914,000093:
023915,000094: 12,3213 00006 EXTEND
023916,000095: 12,3214 15733 BZF RCSMONEX # QUIT NOW IF NO ACTION REQUIRED.
023917,000096:
023918,000097: 12,3215 00006 EXTEND
023919,000098: 12,3216 33221 DCA RCSMONAD
023920,000099: 12,3217 52006 DTCB
023921,000100:
023922,000101:
023923,000102:
023924,000103: 12,3220 0074 EBANK= STATE # NO SWITCHED ERASABLE USED.
023925,000104: 12,3220 02576 54060 RCSMONAD 2CADR RCSMON
023926,000105:
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023928,000107: 26,2576 BANK 26
023929,000108:
023930,000109: 26,2576 30072 RCSMON CA RCSMONT3
023931,000110: 26,2577 00006 EXTEND
023932,000111: 26,2600 77755 MP BIT7 # MOVE BITS 8 - 1 OF A TO 14 - 7 OF L.
023933,000112: 26,2601 56001 XCH L # ZERO TO L IN THE PROCESS.
023934,000113:
023935,000114: 26,2602 24001 -3 INCR L
023936,000115: 26,2603 60000 DOUBLE # BOUND TO GET AN OVERFLOW, SINCE WE
023937,000116: 26,2604 54000 OVSK # ASSURED INITIAL NZ IN A.
023938,000117: 26,2605 12602 TCF -3
023939,000118:
023940,000119: 26,2606 10001 CCS L # PICK UP C(L)-1.
023941,000120: 26,2607 60000 DOUBLE
023942,000121: 26,2610 54073 TS RCSMONT4 # STORE FOR LATER.
023943,000122:
023944,000123: 26,2611 50001 INDEX L
023945,000124: 26,2612 37753 CA BIT8 -1
023946,000125: 26,2613 54072 TS RCSMONT3 # SAVE THE RELEVANT BIT (8 - 1)
023947,000126: 26,2614 70101 MASK LMPJFAIL
023948,000127: 26,2615 10000 CCS A
023949,000128: 26,2616 12637 TCF LMPBIT=1
023950,000129:
023951,000130: 26,2617 00006 EXTEND # LMPBIT = 0.
023952,000131: 26,2620 50073 INDEX RCSMONT4
023953,000132: 26,2621 32654 DCA KILLPAIR # COMMAND TO ISOLATE A PAIR, & ITS RESET.
023954,000133: 26,2622 23162 LXCH JETRESET # PUT THE RESET COMMAND AWAY FOR NEXT TIME
023955,000134: 26,2623 05064 TC STORCOM # SEND THE ISOLATION COMMAND.
023956,000135:
023957,000136: 26,2624 30072 CA RCSMONT3
023958,000137: 26,2625 26101 ADS LMPJFAIL # SET THE BIT SHOWING COMMAND SENT.
023959,000138:
023960,000139: 26,2626 40102 CS CH5MASK # SET THE JET-FAIL BITS IN CH5MASK &
023961,000140: 26,2627 50073 INDEX RCSMONT4 # CH6MASK.
023962,000141: 26,2630 72673 MASK FAILTABL
023963,000142: 26,2631 26102 ADS CH5MASK
023964,000143:
023965,000144: 26,2632 40103 CS CH6MASK
023966,000145: 26,2633 50073 INDEX RCSMONT4
023967,000146: 26,2634 72674 MASK FAILTABL +1
023968,000147: 26,2635 26103 ADS CH6MASK
023969,000148:
023970,000149: 26,2636 15733 TCF RCSMONEX # DONE.
023971,000150:
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023973,000152: 26,2637 40072 LMPBIT=1 CS RCSMONT3 # THE GROUND HAS RE-ENABLED A PAIR.
023974,000153: 26,2640 70101 MASK LMPJFAIL # DON'T USE ADS BECAUSE OF THE -0 CASE.
023975,000154: 26,2641 54101 TS LMPJFAIL
023976,000155:
023977,000156: 26,2642 50073 INDEX RCSMONT4 # TURN OFF THE JET-FAIL BITS IN CH5MASK &
023978,000157: 26,2643 42673 CS FAILTABL # CH6MASK.
023979,000158: 26,2644 70102 MASK CH5MASK
023980,000159: 26,2645 54102 TS CH5MASK
023981,000160:
023982,000161: 26,2646 50073 INDEX RCSMONT4
023983,000162: 26,2647 42674 CS FAILTABL +1
023984,000163: 26,2650 70103 MASK CH6MASK
023985,000164: 26,2651 54103 TS CH6MASK
023986,000165: 26,2652 15733 TCF RCSMONEX # DONE.
023987,000166:
023988,000167:
023989,000168:
023990,000169: 26,2653 5733 RCSMONEX EQUALS RESUME # CHANGE THIS TO ATTACH SOMETHING ON.
023991,000170:
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023993,000172: # IN THE UPPER WORD OF EACH ENTRY OF THE KILLPAIR TABLE IS THE LMP COMMAND CODE TO ISOLATE A JET-PAIR.
023994,000173: # BIT 15 = 1 TO ALLOW USE OF THE "STORCOM" LMP ROUTINE. THE LOWER WORD OF EACH ENTRY CONTAINS THE RESET-COMMAND
023995,000174: # CODE PLUS ONE, WHICH CORRESPONDS TO THE UPPER WORD. (THE EXTRA +1 IS REMOVED BY THE CCS AT RCSMONIT.)
023996,000175:
023997,000176: 26,2653 40250 00252 KILLPAIR 2OCT 40250 00252 # 2A. JETS 10 & 11. CMDS 168 & 169.
023998,000177: 26,2655 40170 00172 2OCT 40170 00172 # 2B. JETS 9 & 12. CMDS 120 & 121.
023999,000178: 26,2657 40134 00136 2OCT 40134 00136 # 1A. JETS 13 & 15. CMDS 92 & 93.
024000,000179: 26,2661 40154 00156 2OCT 40154 00156 # 1B. JETS 14 & 16. CMDS 108 & 109.
024001,000180: 26,2663 40156 00160 2OCT 40156 00160 # 3B. JETS 6 & 7. CMDS 110 & 111.
024002,000181: 26,2665 40310 00312 2OCT 40310 00312 # 4B. JETS 1 & 3. CMDS 200 & 201.
024003,000182: 26,2667 40136 00140 2OCT 40136 00140 # 3A. JETS 5 & 8. CMDS 94 & 95.
024004,000183: 26,2671 40350 00352 2OCT 40350 00352 # 4A. JETS 2 & 4. CMDS 232 & 233.
024005,000184:
024006,000185: # FAILTABL ENTRIES CONTAIN THE BIT FOR CH5MASK IN THE UPPER WORD, AND THE BIT FOR CH6MASK IN THE LOWER.
024007,000186:
024008,000187: 26,2673 00040 00010 FAILTABL 2OCT 00040 00010
024009,000188: 26,2675 00020 00020 2OCT 00020 00020
024010,000189: 26,2677 00100 00004 2OCT 00100 00004
024011,000190: 26,2701 00200 00200 2OCT 00200 00200
024012,000191: 26,2703 00010 00001 2OCT 00010 00001
024013,000192: 26,2705 00001 00002 2OCT 00001 00002
024014,000193: 26,2707 00004 00040 2OCT 00004 00040
024015,000194: 26,2711 00002 00100 2OCT 00002 00100
End of include-file RCS_FAILURE_MONITOR.agc. Parent file is MAIN.agc