Megasquirt presentation from MS meet last weekend
#1
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presentation from MS meet last weekend
Here is a video of the presentation James (one of the original authors of ms1/extra) and I did at the MS meet last weekend.
http://video.google.com/videoplay?do...2237&hl=en
It's mainly just us talking about the past (MS1/extra) the present (MS2/extra 1.0.x) and the future (MS2/extra v2 and a couple of brief mentions of ms3).
Ken
http://video.google.com/videoplay?do...2237&hl=en
It's mainly just us talking about the past (MS1/extra) the present (MS2/extra 1.0.x) and the future (MS2/extra v2 and a couple of brief mentions of ms3).
Ken
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Ken,
Watching the video, you guys mention a significant amount of spark timing loss due to hardware. Can you detail that a bit here?
If people are running a max of 27 deg advance from 3000 through 8k, what kind of timing is really happening? I might have to break out the timing light to see what you speak of.
Thanks
Pete
Watching the video, you guys mention a significant amount of spark timing loss due to hardware. Can you detail that a bit here?
If people are running a max of 27 deg advance from 3000 through 8k, what kind of timing is really happening? I might have to break out the timing light to see what you speak of.
Thanks
Pete
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#4
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Yeah, it was just a couple degrees... but it's enough, and we noticed it, so we added a setting to allow the user to fix it. Use the following procedure to set it:
1) Set fixed timing to something you can measure... -5 on an rx7 works well.
2) Check the timing at idle
3) Rev the engine to around 2000-3000 rpms (if you can... might not be able to with -5 timing)
4) Adjust the new setting up from 0 in increments of 10-20 usec until you can rev the engine slowly without the timing moving.
The latency is really combined from the VR sensor conditioner itself, some software latency, and some other hardware latency.
Ken
1) Set fixed timing to something you can measure... -5 on an rx7 works well.
2) Check the timing at idle
3) Rev the engine to around 2000-3000 rpms (if you can... might not be able to with -5 timing)
4) Adjust the new setting up from 0 in increments of 10-20 usec until you can rev the engine slowly without the timing moving.
The latency is really combined from the VR sensor conditioner itself, some software latency, and some other hardware latency.
Ken
Last edited by muythaibxr; 05-04-07 at 05:44 PM.
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Yeah, it was just a couple degrees... but it's enough, and we noticed it, so we added a setting to allow the user to fix it. Use the following procedure to set it:
1) Set fixed timing to something you can measure... -5 on an rx7 works well.
2) Check the timing at idle
3) Rev the engine to around 2000-3000 rpms (if you can... might not be able to with -5 timing)
4) Adjust the new setting up from 0 in increments of 10-20 usec until you can rev the engine slowly without the timing moving.
The latency is really combined from the VR sensor conditioner itself, some software latency, and some other hardware latency.
Ken
1) Set fixed timing to something you can measure... -5 on an rx7 works well.
2) Check the timing at idle
3) Rev the engine to around 2000-3000 rpms (if you can... might not be able to with -5 timing)
4) Adjust the new setting up from 0 in increments of 10-20 usec until you can rev the engine slowly without the timing moving.
The latency is really combined from the VR sensor conditioner itself, some software latency, and some other hardware latency.
Ken
#6
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I'm not sure from reading your description what you've done. I did the procedure I described above and was able to get rid of all timing change due to latency in the hardware. Meaning my timing would stay locked on -5 even while I revved it.
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thanks
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#8
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I think my latency was around 30 usec. I don't remember for sure off the top of my head. It also depends on some other factors, like what your pots are set to for example.
Another thing I did to help me find the answer was I hooked up my oscilloscope to the VR sensors, and to the output of the conditioner, and measured the time between zero crossing on the VR input and the rise (or fall, depending on where you scope it) of the +5v square wave on the output of the conditioner.
I'll have to find my settings and confirm at one point or another.
Ken
Another thing I did to help me find the answer was I hooked up my oscilloscope to the VR sensors, and to the output of the conditioner, and measured the time between zero crossing on the VR input and the rise (or fall, depending on where you scope it) of the +5v square wave on the output of the conditioner.
I'll have to find my settings and confirm at one point or another.
Ken
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Thanks for you’re help ken
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Sorry for the stupid question, but I am not sure from reading around how you are actually supposed to go about adjusting the latency. I made the firmware update and activated the new ini in the configurator. However, I am kinda confused as to how I might actually change the latency. Sorry I'm kinda out of it.
dpf22
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Sorry for the stupid question, but I am not sure from reading around how you are actually supposed to go about adjusting the latency. I made the firmware update and activated the new ini in the configurator. However, I am kinda confused as to how I might actually change the latency. Sorry I'm kinda out of it.
dpf22
dpf22
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