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LinearX
August 25th, 2010, 08:23 AM
I did some searching and found a reference to the external channels, but I wasn't sure if that included serial. To that end...

I know that most widebands sample at some insanely high rates of speed. To that end, what is the sampling rate of the serial interface?

swingtan
August 25th, 2010, 09:43 AM
I thought the serial sample rate was limited to the actual frame rate in the V2, which means about 10mS/sample in the LS1 and 2.5mS/Sample in the E38 ( or in terms of samples 10/S and 40/S respectively ). Also remember that some WB controllers also have an adjustment for the sample rate as well which can be set to suit whatever it's being fed into. If the WB is feeding samples faster than the V2 reads them, I'd say it just takes whatever sample it arrives when the V2 is checking, ( IE. when the V2 wants to check the serial stream, it will start listening for a "start of data" signal before reading the serial WB information, if the WB is halfway through a sample, the V2 waits for the next full sample ).

On the other hand, the V2 could be reading the serial stream all the time and storing the WB values. What ever is in the stored location when the WB value is required is what ends up in the log.

There are lots of options..... But in the end, you are only going to get the same sample rate as the log file has.

Simon.

LinearX
August 25th, 2010, 10:17 AM
I thought the serial sample rate was limited to the actual frame rate in the V2, which means about 10mS/sample in the LS1 and 2.5mS/Sample in the E38 ( or in terms of samples 10/S and 40/S respectively ). Also remember that some WB controllers also have an adjustment for the sample rate as well which can be set to suit whatever it's being fed into. If the WB is feeding samples faster than the V2 reads them, I'd say it just takes whatever sample it arrives when the V2 is checking, ( IE. when the V2 wants to check the serial stream, it will start listening for a "start of data" signal before reading the serial WB information, if the WB is halfway through a sample, the V2 waits for the next full sample ).

On the other hand, the V2 could be reading the serial stream all the time and storing the WB values. What ever is in the stored location when the WB value is required is what ends up in the log.

There are lots of options..... But in the end, you are only going to get the same sample rate as the log file has.

Simon.

It was going to be my guess that it is limited to the scan rate of the ECU connected, but I wasn't 100% certain. I hadn't been able to find anything definitive.