Source Code
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These source-code files are part of a reconstructed copy of Comanche 44, the
initial release (though not the final mission release) of the Apollo 10
Command Module (CM) Apollo Guidance Computer (AGC) software. Subsequent releases
were Comanche 45 and Comanche 45/2 (the flown release on Apollo 10). The reconstruction
is believed to be exactly accurate, but in the absence of an actual Apollo-era
listing of Comanche 44, some explanation of the reconstruction process is needed
to insure confidence in that accuracy.
The starting point was the source code of Comanche 51 (separately previously reconstructed from an Apollo-era listing of Comanche 55, flown on Apollo 11). Comanche 51 source code was then modified by undoing changes known to have been made between revisions 44 and 51. The now-reconstructed Comanche 44 source code was verified by assembling it and checking that the assembled code had the expected known-correct memory-bank checksums. Note that page numbers in the reconstructed code match those on the Comanche 55 printout, although the source code would likely have different page numbers in a contemporary Comanche 44 listing. Annotations that were not present in the contemporary source code have been added to the reconstructed code to justify each change relative to Comanche 51. Here's a guide to the Apollo documentation referenced in those annotations:
Comments expected to have been present in 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. |
051848,000002: ## Copyright: Public domain.
051849,000003: ## Filename: INTERPRETIVE_CONSTANTS.agc
051850,000004: ## Purpose: A section of Comanche revision 044.
051851,000005: ## It is part of the reconstructed source code for the
051852,000006: ## original release of the flight software for the Command
051853,000007: ## Module's (CM) Apollo Guidance Computer (AGC) for Apollo 10.
051854,000008: ## The code has been recreated from a copy of Comanche 055. It
051855,000009: ## has been adapted such that the resulting bugger words
051856,000010: ## exactly match those specified for Comanche 44 in NASA drawing
051857,000011: ## 2021153D, which gives relatively high confidence that the
051858,000012: ## reconstruction is correct.
051859,000013: ## Assembler: yaYUL
051860,000014: ## Contact: Ron Burkey <info@sandroid.org>.
051861,000015: ## Website: www.ibiblio.org/apollo/index.html
051862,000016: ## Mod history: 2020-12-03 MAS Created from Comanche 51.
051863,000017:
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Page 1205 |
051865,000019: 26,2000 SETLOC INTPRET1
051866,000020: 26,2000 BANK
051867,000021:
051868,000022: 26,3324 COUNT 23/ICONS
051869,000023:
051870,000024: 26,3324 10000 00000 DP1/4TH 2DEC .25
051871,000025:
051872,000026: 26,3326 00000 00000 UNITZ 2DEC 0 B-28
051873,000027:
051874,000028: 26,3330 00000 00000 UNITY 2DEC 0 B-28
051875,000029:
051876,000030: 26,3332 20000 00000 UNITX 2DEC .5
051877,000031:
051878,000032: 26,3334 00000 00000 ZEROVECS 2DEC 0 B-28
051879,000033:
051880,000034: 26,3336 00000 00000 2DEC 0 B-28
051881,000035:
051882,000036: 26,3340 00000 00000 2DEC 0 B-28
051883,000037:
051884,000038: 26,3342 26,3332 DPHALF = UNITX
051885,000039: 26,3342 37777 DPPOSMAX OCT 37777
051886,000040: 26,3343 37777 OCT 37777
051887,000041:
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Page 1206 |
051889,000043: # INTERPRETIVE CONSTANTS IN THE OTHER HALF-MEMORY
051890,000044:
051891,000045: 04,2000 SETLOC INTPRET2
051892,000046: 04,2000 BANK
051893,000047:
051894,000048: 04,3554 COUNT 14/ICONS
051895,000049:
051896,000050: 04,3554 00000 00000 ZUNIT 2DEC 0 B-28
051897,000051:
051898,000052: 04,3556 00000 00000 YUNIT 2DEC 0 B-28
051899,000053:
051900,000054: 04,3560 20000 00000 XUNIT 2DEC .5
051901,000055:
051902,000056: 04,3562 00000 00000 ZEROVEC 2DEC 0 B-28
051903,000057:
051904,000058: 04,3564 00000 00000 2DEC 0 B-28
051905,000059:
051906,000060: 04,3566 00000 00000 2DEC 0 B-28
051907,000061:
051908,000062: 04,3570 77777 OCT 77777 # -0, -6, -12 MUST REMAIN IN THIS ORDER
051909,000063: 04,3571 77771 DEC-6 DEC -6 B-14
051910,000064: 04,3572 77763 DEC-12 DEC -12 B-14
051911,000065: 04,3573 37777 37777 LODPMAX 2OCT 3777737777 # THESE TWO CONSTANTS MUST REMAIN
051912,000066:
051913,000067: 04,3575 37777 37777 LODPMAX1 2OCT 3777737777 # ADJACENT AND THE SAME FOR INTEGRATION
051914,000068:
051915,000069: 04,3577 04,3562 ZERODP = ZEROVEC
051916,000070: 04,3577 04,3560 HALFDP = XUNIT
051917,000071:
051918,000072:
051919,000073:
051920,000074:
End of include-file INTERPRETIVE_CONSTANTS.agc. Parent file is MAIN.agc