Raspberry Pi, and an Instromet logger - USB/ serial adaptor

[Hobbyist]

Hi, After 4 days of playing I am in dire need of some assistance.

I am in the process of getting my Instromet weather logger working with CumulusMX and a Raspberry Pi Model B +

I have test run the Pi and a Fine Offset weather station and managed to get that combination to work without a problem.

I have then transferred the Instromet logger onto the Raspberry Pi but I can't for the life of me get them to talk.

It is not a CumulusMX fault it is obviously something to do with the fact that the Instromet logger has a serial to USB adaptor installed.

I have checked on the Pi and found that the 'USB' port on the PI is ttyUSB0 and put that into cumulus as the 'COM' port but there is no data flow at all.

The USB/Serial adaptor is, after investigation, an FTDI EVAL232 board.

I have looked at the FTDI site and they have an ARM (PI) driver available but I can't see how you install that onto a raspberry PI.

It is the only thought I have left as a solution to my problem.

Has any one got a 'simple' method of getting a possibly missing driver onto a Raspberry PI

or any thoughts on why I am having this problem.

I would appreciate any suggestions.

Thanks

Dave

[steve]

I have checked on the Pi and found that the 'USB' port on the PI is ttyUSB0 and put that into cumulus as the 'COM' port but there is no data flow at all.

What exactly haver you entered in the 'serial port name' box in the MX settings? You have to supply the full device name, e.g. /dev/ttyUSB0 - as mentioned in the MX FAQ.

2015-10-25 11_13_47-serialportname.png

[Hobbyist]

Hi Steve, yes I can confirm that is exactly what I entered after having read up on the Forum.

I was just assuming, possibly wrongly, that the Pi driver was incorrect for the adaptor.

My Linux/Pi programming experience is almost zero.

Thanks for the reply.

Dave

[steve]

Turn on debug logging and data logging by editing Cumulus.ini, and then start MX. Then zip up the latest MXdiags file and attach it here, and I'll take a look.

[Hobbyist]

Many thanks for the offer Steve but I may have solved it.

I did a complete upgrade of the Pi software and there now seems to be signs of data flow.

It takes the Instromet logger an inordinate amount of time to download historical stuff but I am 'confident' it may be working.

If not I will do as you asked.

Thanks for your assistance.

Dave

[Hobbyist]

How wrong I was!

A flashing data light was not telling the whole story.

I can't seem to 'Turn on debug logging and data logging by editing Cumulus.ini' as I can't find them on that file Steve. I have attached a copy for you, I am probably text blind!

I have attached some relevant MXdiags files which seem to be showing that CumulusMX is finding many checksum errors and eventually shuts down. I am not sure why that should be but maybe you have a suggestion.

Thank you once again

Dave

[steve]

It's quite possible that there's a bug in my code in MX which validates the checksum - I'm not sure anyone has tried MX with an Instromet yet (and I sent the one I was using back to Instromet before I started working on MX, so never had chance to test it). I'll have a look at the code and get back to you.

[Hobbyist]

Thanks Steve and if you need any checks/test made, this end, just post.

Cheers

Dave

[steve]

There is indeed a bug in my checksum code - I'll fix it in the next build.

[Hobbyist]

Cheers Steve only problem is, that now you have found the problem, I have no excuse to resisting demands to do the gardening

Dave

[Hobbyist]

Hi again Steve, I have downloaded and installed MX version 3032 but unfortunately I seem to be having the same problem of an invalid checksum with my Instromet.

I have attached a couple of MXdiags files for your perusal.

many thanks

Dave

[steve]

The invalid checksum message is for the response to reading the number of available logs. It's not clear why the fix to the checksum calculation didn't also fix that. I don't currently log the response so it's not clear why the checksum fails. I'll add logging of the response to the next build.

It then crashes having read the first live data and passed the checksum check - so the fix apparently works, as it's getting past that part. It's crashing while trying to parse the response to extract the data values. I've found the problem, it isn't catering for missing values in the response - I'll fix it in the next build. I'm afraid that this is typical of how this is likely going to go, one step at a time.

[Hobbyist]

Cheers Steve and one step at a time is progress and that is what a Beta test is all about.

Thank you for the prompt reply.

Dave

[Hobbyist]

Hello Steve, I have downloaded and run MX version 3033 this morning and tried once again to connect to my Instromet system.

Unfortunately I am still having a problem for which I have attached the MXdiags file.

Thank you

Dave

[steve]

Looks like a problem with the serial/USB connection. It's not getting as far as it was previously (and that code is unchanged). The virtual serial port returns an error when Cumulus tries to read from it. You could perhaps try unplugging the cable and plugging it in again, or perhaps rebooting the Pi.