Logging GPS and NEMS without OBD ?

[ggiraudon]

Hi all,

I've been playing around with my data loggers for a few days but have had a hard time getting anything logged.
Out of desperation, I've added a small routine do log the setup steps of the CBODLogger class into a file on the SD card.
I can confirm that the SD card works at this point as my log file does populate. That being said, I seem to be entering an infinite loop around the OBD init()

With that in mind, I have a couple of questions :

The source repo has 3 versions of the firmware : V1, V2 and V3 . I've using V3... is that the correct one to use ?
(I have the Data Loggers with the BTLE module and the MTK-3329 GPS module)

Is there a way to log NEMS and GPS only and just use the OBD plug for power (ie, avoid the code portions pertaining to CAN/OBD) ?

I see that the 10HZ AT command is commented out in the initGPS section. Is there any reason not to uncomment it ?

On the board, what are J4 and J6 for ?
I've been trying to find a place to hook up some sort of debugging port (I guess we're out of UARTs but a digital IO and SoftwareSerial might work if any are available).
Is there a schematic of the board somewhere that I might look at to find a way to hook up a bus pirate or similar ? Having to pop the SD card out every time I wish to see the debug logs is a bit tedious.

Will the current firmware allow me to capture 10hz NEMS and GPS (with or without OBD) ?

Thanks in advance.

G

[ggiraudon]

Ok.. after a bit more tinkering, I've been able to view the debug info in VERBOSE mode using a CC2450 USB Dongle and connecting to the BTLE module.

Still having the same issue however, looping at the OBD init step.

Can I power the Logger by giving it 12v on pins 16 and 4 of the OBD connector ?

If the module is powered via J2 (5V), does it have enough power to run everything or should it be powered via the OBD port in order to have enough of a punch to power the rest of the ICs (like the STM) ?

[ggiraudon]

Still... making more progress. I found that the OBD Init loop was caused by low voltage. Powering the logger with 16v on the OBD power (pins 16 and 4) works a treat.
Now I have another problem. I cant seem to get the file system right on the SD card.
I either get corrupt files or a single file called FRMATICS (which should be a folder) and some garbage inside.

I'm using an 8Gb Class 10 SDHC card. Does anyone know what the formating parameters should be ? I've tried FAT32 with 32Kb Cluster (with the Windows 7 format utility as well as the SD Formater 4 utility).

I actually changed SD cards to make sure it wasnt a faulty one but still no luck.

I guess FAT16 is out of a question with a card this size. The SD library seems to support any cluster size... but clearly I'm doing something wrong.... any ideas ?

[ggiraudon]

Well, after a bit of tinkering and reorganizing, I decided to actually build a simpler version of the data logger firmware.
Not that there's anything wrong with the Stanley's code mind you... but I needed something simpler, with a different file format in the output and had no need of the OBD/CAN part.

So I made a "lite" version of the firmware that just logs NEMS and GPS to the SD card in a simple series of CSV files.

You can find the code here :

https://github.com/ggiraudon/FreematicsBaseline

Let me know if you have any questions.