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Author Topic: Virtual AGC  (Read 166463 times)
indy91
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« Reply #690 on: October 09, 2016, 01:02:19 PM »

My math doesn't line up with exactly 20 seconds, but I found and fixed this: https://github.com/rburkey2005/virtualagc/commit/e30fefb1ace7abd318b0c7a4b3bf08f1cbde1eb0

That would skew the clock by 1/3200 of a second every 5.12 seconds (or 1/1600 of a second pre-standby-addition). That's in the same ballpark of error, at least.

20 seconds was actually a pretty bad estimate because I couldn't be bothered to look up the exact number. It's actually 15 seconds and that seems to be exactly the error caused by the "1/3200 of a second every 5.12 seconds", with the AGC changes for the standby mode in my local copy. And the error seems to have been there since the 401 alarm fix with the special case for DV (https://github.com/rburkey2005/virtualagc/pull/53) corrected phasing for TIME4 and TIME5 (https://github.com/rburkey2005/virtualagc/pull/49). So that confirms the theory that something was off with the AGC clock for a few weeks already. Thanks again for the quick fix!
« Last Edit: October 09, 2016, 01:05:15 PM by indy91 » Logged
rcflyinghokie
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« Reply #691 on: October 09, 2016, 09:38:28 PM »

So that confirms the theory that something was off with the AGC clock for a few weeks already. Thanks again for the quick fix!

Should this also fix that PDI timing error?  Or is this specifically for the P06?
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thewonderidiot
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« Reply #692 on: October 09, 2016, 09:45:29 PM »

Yeah, it'll also fix that timing error. Sorry about that.
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indy91
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« Reply #693 on: November 21, 2016, 02:01:35 PM »

Last month we talked about sponsoring the Zerlina 56 scans as a NASSP group. With 1735 pages and a price of "$3 plus $0.25/page" this results in $436.75. I am positive we are able to get this amount together with a few people here. I can't personally give much currently, but I want to advertise this again, so it's not forgotten.  Happy
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kneecaps
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« Reply #694 on: November 21, 2016, 02:06:45 PM »

Last month we talked about sponsoring the Zerlina 56 scans as a NASSP group. With 1735 pages and a price of "$3 plus $0.25/page" this results in $436.75. I am positive we are able to get this amount together with a few people here. I can't personally give much currently, but I want to advertise this again, so it's not forgotten.  Happy

I'll pledge $50 USA to this. I do want to see this code!
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"Okay. As soon as we find the Earth, we will do it."
- Frank Borman, Apollo 8

Current Work: ?? What next??

Future Work:
I know the AGC pretty well so anything need doing there?

On Hold/Completed:
SPS TVC in P40 issues.
P11 FDAI Error Needles (98%) complete. Comitted. Working A7 scenario.
P06 AGC Standby. Concluded. It's done by the AGC PSU.
Got us a complete AOH Volume II
indy91
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« Reply #695 on: November 22, 2016, 11:13:49 AM »

I'll pledge $50 USA to this. I do want to see this code!

That is the amount I would be contributing, too. That means we only need 7 more people convering the costs, provided nobody wants to give more. Just to make it clear again what Zerlina 56 actually is and why we want to have it, here is what Don Eyles, AGC developer, has to say about Zerlina 56:

Quote
    "ZERLINA was my personal non-flight testbed for developing new
    capabilities, some of which later moved to the main line LUMINARY.
    Its main feature was a new version of the Servicer job in which the
    guidance period was allowed to stretch beyond the nominal 2 seconds
    — part of the overall effort in response to the CPU overload on 11.
    Variable Servicer would have been necessary if new capability was
    required that would have further reduced our CPU margin, such as
    something called P66 LPD, also implemented in ZERLINA, based on an
    idea of John Young's, that would have facilitated making very
    accurate landings. This capability is described in Draper Lab report
    E-2581, which I can at some point make available. Neither Variable
    Serviver nor P66 LPD was ever approved for LUMINARY. Things
    developed first in ZERLINA that DID make the jump to LUMINARY
    included the a priori terrain model (needed to land in more
    mountainous terrain), and also a new version of the "landing analog
    displays," the same mentioned in the Tindallgram of July 24, 1970.
    In my view ZERLINA 56 still represents the state of the art for
    manned landings on the Moon."
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indy91
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« Reply #696 on: December 16, 2016, 07:31:01 AM »

Doesn't look like there is too much interest  Sad

Two new AGC versions are available from the Virtual AGC project: Luminary 069 and Luminary 210. Luminary 069 is almost the flown Apollo 10 LGC version. Almost because the flown version was Luminary 069 Rev. 2. I think we understand the differences between the versions and it will be no problem to implement this version.

Luminary 210 is the version flown on Apollo 15-17. Will be really fun to try the a lunar landing at Hadley–Apennine, flying over those mountains and land next to Hadley Rille. This version also has an extended Erasable Memory Program (EMP) capability. What they did to deorbit the LM for the J-Missions was load a complete program into the erasable memory, using hardcoded routines of course. This was Program 99 and was essentially P42 without requiring any astronaut inputs. On earlier flights the ground had to uplink commands to the LM for this. So these new features will be fun to try one day.

I also have a request for someone who knows how to edit bitmaps. Luminary 210 uses two more DSKY lights: NO DAP and PRIO DISP. For that the DSKY lights bitmap will have to be edited. Here is it how it should look like, in the picture next to "LM, Apollo 17": http://www.ibiblio.org/apollo/yaDSKY.html#The_Warning_or_Indicator_Lamps What you have to do is go into the \Orbitersdk\samples\ProjectApollo\Bitmaps folder and find the file dsky_lights.bmp. And then just add the displays for NO DAP and PRIO DISP.
« Last Edit: December 16, 2016, 07:32:40 AM by indy91 » Logged
thewonderidiot
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« Reply #697 on: December 16, 2016, 11:35:27 AM »

I'm also willing to foot a decent bit of the Zerlina bill, but any more help would of course be hugely appreciated.  Wink

As far as NO DAP and PRIO DISP, I don't think there's any more editing that needs to be done, unless the goal is to make things easier for beginners. Both the Apollo 15 and Apollo 16 Delco manuals indicate that the labels weren't shown on the lights in the LM (though I guess we can't be sure about 17). The only DSKY I've seen a picture of that actually had such labels is this one:


But I'm really unclear as to what this DSKY is. The sign behind it has the logo for Apollo 8, but claims that this DSKY flew on Apollo 10. However, it's a LM DSKY, and I was under the impression that 10's ascent stage was hanging around in space somewhere. Did they remove the DSKY from the LM before undocking? It seems kind of unlikely, and I can't find any documentation about it.

Furthermore, the PRIO DISP and NO DAP labels are in the wrong places, and neither had been implemented for Luminary 69. Also, the digital indicator is missing its protective frame, so it must have been disassembled and then only mostly reassembled after flight for some reason. So, who knows.

e: Now I'm really confused. Here's an Apollo 17 LM closeout picture from the ALSJ:


It also has the labels swapped from the Delco manuals....
« Last Edit: December 16, 2016, 11:40:42 AM by thewonderidiot » Logged
rcflyinghokie
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« Reply #698 on: December 16, 2016, 11:41:18 AM »

Likely a dsky from a simulator given the wear on the buttons
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thewonderidiot
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« Reply #699 on: December 16, 2016, 11:57:04 AM »

Did some more digging. Apollo 15's closeout pictures have the DSKY obscured, but here's an Apollo 16 closeout picture that has labels agreeing with the two above images: https://www.hq.nasa.gov/alsj/a16/LM11-co46.jpg

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indy91
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« Reply #700 on: December 16, 2016, 12:02:15 PM »

Apollo 16 also had them in that order:

Link posted above.

Where is the information on the ya DSKY page from? Must be wrong then. ROTFL

Also, the lights were definitely functional. The Apollo 15 LM Activation Checklist mentions that with a Verb 35 all lights except the NO DAP light are on. I haven't looked for it in Luminary 210, but I guess even the NO DAP light will be used somewhere there.
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thewonderidiot
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« Reply #701 on: December 16, 2016, 12:22:42 PM »

I think that information must have originally come from the A15 Delco manual. At least, that's what I've been using and assuming was correct all this time.  Rolling Eyes  Barring any other evidence, though, I guess we'll just have to assume it's wrong.

Also, "The Apollo 15 LM Activation Checklist mentions that with a Verb 35 all lights except the NO DAP light are on" reeeaaallly? That's strange. I did a V35 in Luminary 210 very shortly after we finished transcription of its octals, and this is what I got:


Granted, I did indeed not have DAP in control at the time, but the PINBALL code for the light test does set the NO DAP bit for light tests: http://www.ibiblio.org/apollo/listings/Luminary210/PINBALL_GAME__BUTTONS_AND_LIGHTS.agc.html#545354434F4E32
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indy91
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« Reply #702 on: December 16, 2016, 12:32:23 PM »

I guess I can't read. Here is the checklist excerpt:



The NO DAP light just doesn't reset the same way as the other lights.
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thewonderidiot
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« Reply #703 on: December 16, 2016, 12:38:18 PM »

Aha! That makes more sense. I guess, based on the observed behavior above, that's meant to mean that No DAP resets ASAP instead of potentially waiting 5 seconds. Happy
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indy91
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« Reply #704 on: December 16, 2016, 01:55:09 PM »

I also have a request for someone who knows how to edit bitmaps. Luminary 210 uses two more DSKY lights: NO DAP and PRIO DISP. For that the DSKY lights bitmap will have to be edited. Here is it how it should look like, in the picture next to "LM, Apollo 17": http://www.ibiblio.org/apollo/yaDSKY.html#The_Warning_or_Indicator_Lamps What you have to do is go into the \Orbitersdk\samples\ProjectApollo\Bitmaps folder and find the file dsky_lights.bmp. And then just add the displays for NO DAP and PRIO DISP.

So I guess this request is still valid. Except the NO DAP and PRIO DISP lights have to be done as in the pictures above and not like on the Virtual AGC website.
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