Is it possible to actually log, or view the cam sensor signal voltage?
As I increase revs I eventually receive a cam error. I'm assuming it's down to the signal no-longer passing through either the upper or lower trigger thresholds. My understanding of this is that, as my set-up is falling edge, the ecu see's a cam trigger when the voltage passes from the through the upper threshold past the lower threshold? If it was just a case of it passing a single threshold it would not be able to tell if it was a rising signal or a falling signal, correct?
If I could actually log what the voltage from the cam sensor is, then I could set the cam trigger thresholds to suit, but the only thing I seem to be able to log is camraw which, if I'm correct, just tells me when the trigger is occuring.
Cheers,
Tony
logging cam sensor signal
Re: logging cam sensor signal
Ah sussed it. I hadn't spotted the individual inputs were available at the bottom of the list of loggable values. 
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pat
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Re: logging cam sensor signal
Tony,
Logging an02v is possible (assuming that's where you're sending your signal) but the sampling rate is probably too slow, even at 1kHz, so that's why we have the Sync Scope. There is a background process that monitors the crank and cam signals continuously and if an error happens it captures the events up to the error. When it happens you can use Device -> View SyncLog to look at an "oscilloscope" trace of the waveforms leading up to the problem. In the datalogging section of the config you can configure the sampling rate for the sync scope up to 100kHz, you may need to try different sampling speeds to get the best result, if it's too slow you lose detail, if it's too quick you may actually miss the event itself (the buffer is only so big and some time has to elapse before it says "hey, shouldn't I have seen a tooth by now?" - occurrence slightly later than expected is normal in the event that the engine is slowing down so we do have to allow some tolerance, if you see what I mean).
The idea behind this was if you're out on track and you get a cough, when returning to the pits one can quickly grab the sync log and immediately see the problem, fix it and send the car back out, all in a matter of seconds
But it is a very useful diagnostic tool, even when time is not of the essence, you will actually see what is going on and you'll know what to adjust to fix it, rather than just guessing at it!
Hope this helps,
Pat.
Logging an02v is possible (assuming that's where you're sending your signal) but the sampling rate is probably too slow, even at 1kHz, so that's why we have the Sync Scope. There is a background process that monitors the crank and cam signals continuously and if an error happens it captures the events up to the error. When it happens you can use Device -> View SyncLog to look at an "oscilloscope" trace of the waveforms leading up to the problem. In the datalogging section of the config you can configure the sampling rate for the sync scope up to 100kHz, you may need to try different sampling speeds to get the best result, if it's too slow you lose detail, if it's too quick you may actually miss the event itself (the buffer is only so big and some time has to elapse before it says "hey, shouldn't I have seen a tooth by now?" - occurrence slightly later than expected is normal in the event that the engine is slowing down so we do have to allow some tolerance, if you see what I mean).
The idea behind this was if you're out on track and you get a cough, when returning to the pits one can quickly grab the sync log and immediately see the problem, fix it and send the car back out, all in a matter of seconds
But it is a very useful diagnostic tool, even when time is not of the essence, you will actually see what is going on and you'll know what to adjust to fix it, rather than just guessing at it!Hope this helps,
Pat.
Re: logging cam sensor signal
That is a very cool function! I like that a lot!! 
Thanks Pat.
Thanks Pat.
Re: logging cam sensor signal
I've just had a look at this.
I take it the upper trace is the crank and the lower is the camshaft? What do the green vertical lines represent?
Also I'm struggling to find where I can adjust the frequency of the sync scope frequency. The only thing I can find when I open up Scfg is loggingActive, which has has no value at all next to it, but I'm assuming that will just send a signal to say "yes I'm logging" or "no I'm not logging".
Perhaps I'm looking in the wrong area altogether?
Cheers!
Tony
I take it the upper trace is the crank and the lower is the camshaft? What do the green vertical lines represent?
Also I'm struggling to find where I can adjust the frequency of the sync scope frequency. The only thing I can find when I open up Scfg is loggingActive, which has has no value at all next to it, but I'm assuming that will just send a signal to say "yes I'm logging" or "no I'm not logging".
Perhaps I'm looking in the wrong area altogether?
Cheers!
Tony
Re: logging cam sensor signal
looks like I was looking in the wrong area! 
For future searches, it can be found in Scal, Logging functions, sync scope, sync scope frequency.
For future searches, it can be found in Scal, Logging functions, sync scope, sync scope frequency.