Standalone Logging to MicroSD w/ OPv2.0

[keithk831]

P.S. I have a new Lexar 2GB card. Formatted in FAT. And I installed the ecuFlash beta and updated the firmware.

[keithk831]

Geez....noob error. I had my file named as logcfg.txt.txt

 

I just went and tested the logging while parked. Looks like it's working fine except some of the values are weird. Namely the manifold relative pressure. The values look like "63508700"

 

Another weird thing is the engine speed is recording decimals as well. But that's not as important.

 

I'll attach a log so you can see...

log0002.csv

[enthusiast]

<snip>

...some of the values are weird. Namely the manifold relative pressure. The values look like "63508700"

 

What ECUID are you using?

[enthusiast]

Sample times are not microSD dependent here.

 

If you use K-line, which you do then yes this is normal. K-line is half-duplex and operates at 4800bps.

The more parameters you log the longer the query interval.

Two parameters: RPM, Throttle = 0.08 secs per sample

Nine parameters like for a WOT run = 0.15 secs per sample

 

Basically each parameter adds about 0.012 secs to the query interval.

 

Good explanation. Where is this documented?

 

As for the updated firmware in the OP2, you should still be able to use the older version 1.42 of ECUFlash without a problem. If you installed 1.43 just uninstall it and the drivers and go back to 1.42. I saw a post about that but can't find it ATM.

Dale

 

Was it this one?

http://www.romraider.com/forum/topic5999.html

 

Presently I am trying to get the RPN function on the online generator to not have any division (for better speed). The stack switching is driving me crazy.

[keithk831]

what ecuid are you using?

 

a2wc510n

[LGTspecB1657615261]

Geez....noob error. I had my file named as logcfg.txt.txt

 

I just went and tested the logging while parked. Looks like it's working fine except some of the values are weird. Namely the manifold relative pressure. The values look like "63508700"

 

Another weird thing is the engine speed is recording decimals as well. But that's not as important.

 

I'll attach a log so you can see...

 

MRP 4 byte does not work for me either. Just use the standard 8 bit (listed first), it works fine. Engine load 4 byte does not work, 2 byte is the only one that works. Just keep trying the different variations of the parameter and one will work.

[keithk831]

MRP 4 byte does not work for me either. Just use the standard 8 bit (listed first), it works fine. Engine load 4 byte does not work, 2 byte is the only one that works. Just keep trying the different variations of the parameter and one will work.

 

Thanks for the tip...i'll try that!

[dschultz]

Good explanation. Where is this documented?

It maybe somewhere on the RR or OpenECU sites, but really it's just math.

In it's simplest form,

Logger sends a request which is a header and parameter(s) to retrieve. The ECU responds with a header and the value.

Most parameter requests are 3 bytes long and replies are 1 byte long.

So 4 bytes of data (ignoring headers) are passed on the K-line. At 4800 bps the 4 byte = 32 bits. 32/4800 = 0.007 seconds for this parameter. When you add the headers it's longer of course. One parameter request takes a baseline of about 0.065 seconds. So you can start adding from there.

 

 

Was it this one?

http://www.romraider.com/forum/topic5999.html

 

Yes

[keithk831]

So what's the difference between 2-byte and 4-byte?

[LGTspecB1657615261]

So what's the difference between 2-byte and 4-byte?

 

16 bit vs 32 bit.

 

resolution of the signal I believe.

 

For logging purposes, it does not matter IMO.

[dschultz]

So what's the difference between 2-byte and 4-byte?

If you are referring to the parameters you are able to retrieve...? some have three options:

1 byte, lowest resolution and will be limited in dynamic range, 0 - 256

2 byte, better dynamic range with some loss of precision, 0 - 65535

4 byte, this is the value the ECU uses internally for calculations. It gives the best dynamic range but the cost is that it takes much longer to transmit these values on the wire. So only a couple can be queried at a rate of x samples per second.

[keithk831]

So, in most cases, which option is the best for datalogging purposes?

[dschultz]

Well that depends on what you are trying to identify in the log you are doing. Logged parameters should be specific to what you want to learn, whether it be a WOT run looking for knock or tuning boost, etc.

If you are using K-line the 1-byte parameters will allow for more samples per second which may be better than a 2 byte parameter and few samples per second, especially if you are looking for a blip or some transitional state.

The RR FAQ has some info about what is good to log:

http://www.romraider.com/Documentation/RomRaiderFAQ#toc62

[Legacy_GT_Pilot]

Is there anything special that you need to do so a PC recognizes the card? I've installed the newest version of ECU Flash and did the firmware update. But when I plug my Tactrix cable into my PC with the SD mini card inserted, my computer doesn't recognize it. Thoughts?

[dschultz]

It most likely needs to be powered from the ODB-II connector. USB power is probably not enough to get the OP2 booted up.

[keithk831]

Is there anything special that you need to do so a PC recognizes the card? I've installed the newest version of ECU Flash and did the firmware update. But when I plug my Tactrix cable into my PC with the SD mini card inserted, my computer doesn't recognize it. Thoughts?

 

Not sure. Mine works just fine connected to my laptop without being connected to the car. Try restarting your computer and try the firmware update again to see if it lets you.

 

What size of SD card did you get?

[LGTspecB1657615261]

Is there anything special that you need to do so a PC recognizes the card? I've installed the newest version of ECU Flash and did the firmware update. But when I plug my Tactrix cable into my PC with the SD mini card inserted, my computer doesn't recognize it. Thoughts?

 

Update firmware in Tactrix?

[Legacy_GT_Pilot]

Thanks - I will try that tonight and see if it works.

 

It most likely needs to be powered from the ODB-II connector. USB power is probably not enough to get the OP2 booted up.

[Underdog]

+1 to what Keith said. If I have the OP2 hooked up to my laptop and not to the car, it still lights up and registers the mSD card as a removable disk.

[Legacy_GT_Pilot]

I've tried 2 different 2GB cards. I've done the firmware update multiple times and rebooted my machine several times as well. Everytime the SD card doesn't show up, but the port lights up as expected.

 

I will try the connection to my car, and will also try the cable on my home PC to see if that works as well.

 

Dave

 

Not sure. Mine works just fine connected to my laptop without being connected to the car. Try restarting your computer and try the firmware update again to see if it lets you.

 

What size of SD card did you get?

[Underdog]

I found that I had to put the card in first, then plug it into the computer. If I plugged it into the computer first, then inserted the card, it wouldn't show up as a separate drive.

[05pearl]

[keithk831]

I found that I had to put the card in first, then plug it into the computer. If I plugged it into the computer first, then inserted the card, it wouldn't show up as a separate drive.

 

X2. I haven't tried plugging in the card after the cable was already plugged in, but I have my card in the cable all the time and I have never had a problem.

[H2Otx]

Here is a stupid question but does the mSD card click in? Or do you just slide it in and it chills?

[keithk831]

Here is a stupid question but does the mSD card click in? Or do you just slide it in and it chills?

 

Mine clicked in.