MLV HD 4.2.01 struggling with Sync error logger?

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SwedCharger-67
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Joined: Sun Dec 23, 2012 2:20 pm
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MLV HD 4.2.01 struggling with Sync error logger?

Post by SwedCharger-67 »

I have a sync error that I'm trying to get rid of.

Unfortunately it seems that most of the time I'm trying to understand what MLV HD is doing when I load the Sync Error log. The behavior seems a bit unpredictable...
- sometimes the cam signal is shown as a square wave, but most of the time a spike as I think it should be.
- sometimes when I click on the graphic side it marks the corresponding spot in the numerical window, sometimes it does nothing.
- sometimes I have 3 tabs in the numerical window...right now just one...when I have 3 tabs I seem to remember one is called "raw data".

Here is the most recent Sync error log, I have identified a double tooth reading in page 8 of the total 9, but apart from that I cannot make much sense of the Sync error log.
Previous Sync error log looked similar, recorded with a fairly powerless laptop. This latest log is recorded with a fairly powerful laptop...but no difference.

Current status is that I'm not going to use the Sync error logger anymore, it tends to confuse me more than explain what's happening. Anyway, looks like I have to explore the double tooth VR crank reading hint.
Martin, Sweden
Mopar 512 cui, 8.4 liters, high compression, fuel E85, full sequential control by MS3X, burning rubber just blipping the throttle... :D
LT401Vette
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Re: MLV HD 4.2.01 struggling with Sync error logger?

Post by LT401Vette »

The composite log viewer has to figure out how to render based on the data in the log. With no blank pages or few records, there can be not enough info to render it properly.
To render as a single edge (single up or down line) or a double edge (square wave), is driven by the data for each trigger being:
all high - Single Edge rising
all low - Single Edge falling
both high and low - Square wave.

That log has varying data by page:
Page 1 is essentially blank.
Page 2 is blank except the last record
Page 3 is blank except the last record
Page 4 is blank for the 1st half, then starts having cam data, no crank data. It has the 1st cam data record shows as low, the remaining are high, thus it is rendered as double edged.
Page 5 is again blank except the last record.
Page 6 has clean data and rendered as cam and crank with single edge.
Page 7 Is blank for the 1st 1/3rd of the log, then has a very long crank tooth time that produces the long flat time. There is high and low data for the crank, so it is rendered as a square (when it is physically not)
Page 8 contains only single edge data, but a very long tooth time in the middle as displayed.
Page 9 Once again has no data for the beginning, then one crank record triggered low followed by a long crank triggered high making it look double edged, this is then followed by more normal looking single edge data.

What is interesting here is why does your data vary so much, especially page to page. The blank or largely blank pages would imply the engine was probably not running and they are timed out reads.
However, the pages that are all blank except the last record seems odd and probably more odd is that page 6 is a clean log of an engine accelerating from about 3000 RPM to 4100 RPM, but the page immediately before and after don't have clean running data.

Was this log spliced together from multiple files?

Otherwise it looks as though there is a problem in the capture between TS or the firmware.
Phil Tobin
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SwedCharger-67
Experienced MS/Extra'er
Posts: 264
Joined: Sun Dec 23, 2012 2:20 pm
Location: Nordmaling, Sweden

Re: MLV HD 4.2.01 struggling with Sync error logger?

Post by SwedCharger-67 »

Thanks Phil for your comments.

- No, this is a single Sync Error file captured during a single run, with a fairly powerful laptop.
Simultaneously I was logging normal data on an SD memory card in the MS3X box.

I attach a log file from the corresponding run, logged on the SD-card. You will see several instances of fat sync errors. However, I don't know how these correlate with the Sync Error log, but both files are captured during the same test run.

The Lost Sync count went from 1 (generated at engine start) to a total of 6 during this test run.
Martin, Sweden
Mopar 512 cui, 8.4 liters, high compression, fuel E85, full sequential control by MS3X, burning rubber just blipping the throttle... :D
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