mathewjenkinson
Posts: 60
Joined: Mon Mar 26, 2012 8:13 am

Unable to find USB/TTY GPS unit

Thu Sep 19, 2013 8:06 am

Hi all,

Ive purchased a Gosget BU-373 USB GPS unit, in the hope of being able to pick up GPS signals via my pi.

Using the command "sudo lsus "I can see the device registered as "Bus 001 Device 004: ID 1546:01a6 U-Blox AG" but I cant find it within /dev/ - i know im looking for /ttyUSB0 but none exist.

I've been following the guide from lady ada : http://learn.adafruit.com/adafruit-ulti ... rything-up

assuming that the gps would be detected in the same way; Do I need to install any gps drivers? Would anyone have any suggestions on where I begin to troubleshoot this?

Many thanks,
Mathew

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DeeJay
Posts: 2027
Joined: Tue Jan 01, 2013 9:33 pm
Location: East Midlands, UK

Re: Unable to find USB/TTY GPS unit

Thu Sep 19, 2013 8:27 am

The dmesg command dumps out a log of system messages.

You could look at that to see if there is anything relevant.

Querying it with something like grep might help narrow it down.

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dmesg | grep -i tty
or

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dmesg | grep -i usb

Google seems reluctant to yield any information about Gosget - the only links I can find are to ebay resellers - so it's difficult to know what OS support you might need. Most USB GPS dongles I have encountered contain a Prolific PL2303 serial port convertor, which has been supported in the linux kernel for some time (ie. years).

That's something else you might scan for -

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dmesg | grep 2303
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mathewjenkinson
Posts: 60
Joined: Mon Mar 26, 2012 8:13 am

Re: Unable to find USB/TTY GPS unit

Thu Sep 19, 2013 8:46 am

Hi,
Thanks for the info.

A quick Google on 'U-Blox AG' shows a website for a company who produce wireless comms chips inc GPS.

The results from

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dmesg | grep -i tty
[    0.000000] Kernel command line: dma.dmachans=0x7f35 bcm2708_fb.fbwidth=1680 bcm2708_fb.fbheight=1050 bcm2708.boardrev=0xe bcm2708.serial=0x28de1b00 smsc95xx.macaddr=B8:27:EB:DE:1B:00 sdhci-bcm2708.emmc_clock_freq=100000000 vc_mem.mem_base=0x1ec00000 vc_mem.mem_size=0x20000000  dwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=tt AMA0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait
[    0.000000] console [tty1] enabled

and dmesg | grep -i usb returns:

[code]

[    3.531788] usb 1-1.2: Product: u-blox 6  -  GPS Receiver
[    3.549985] usb 1-1.2: Manufacturer: u-blox AG - www.u-blox.com
[    3.662050] usb 1-1.3: new full-speed USB device number 5 using dwc_otg
[    3.794435] usb 1-1.3: New USB device found, idVendor=046d, idProduct=c52b
[    3.819909] usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber 
[ 0.585147] dev:f1: ttyAMA0 at MMIO 0x20201000 (irq = 83) is a PL011 rev3
[ 0.916816] console [ttyAMA0] enabled
[ 5.589136] cdc_acm 1-1.2:1.0: ttyACM0: USB ACM device
[/code]

from this I can see ttyACM0 sticks out, would this be inplace of any ttyUSB0?

Thanks,
Mathew

mathewjenkinson
Posts: 60
Joined: Mon Mar 26, 2012 8:13 am

Re: Unable to find USB/TTY GPS unit

Thu Sep 19, 2013 8:55 am

Quick update to this:

from

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 dmesg | grep -i tty
The output showed my device as: "ttyACM0", piping this to:

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sudo cat /dev/ttyACM0
results in lots of GPS data being output, however when I try to pipe this to gpsd by:

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sudo gpsd /dev/ttyACM0 -F /var/run/gpsd.sock
and then running:

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cgps -s
results in a time out.

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DeeJay
Posts: 2027
Joined: Tue Jan 01, 2013 9:33 pm
Location: East Midlands, UK

Re: Unable to find USB/TTY GPS unit

Thu Sep 19, 2013 9:02 am

I think ttyACM0 is the default serial console.

It looks as though the kernel is not recognising the vendor/product codes.

That's the end of the road for me: I need to back out here and hope someone else might step up to help.

PS: Googling for that vendor/product code usually returns results for Logitech devices. Odd.
There is a document on the u-blox site that might help - I haven't downloaded and read it.
http://www.u-blox.com/en/drivers-a-midd ... river.html

PPS: I might be wrong. Step 2.2 of those instructions suggest that the ttyACM0 port might indeed be your gps.
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mathewjenkinson
Posts: 60
Joined: Mon Mar 26, 2012 8:13 am

Re: Unable to find USB/TTY GPS unit

Thu Sep 19, 2013 9:27 am

Hi all,
Another update:

USBACM0 is indeed my USB GPS unit, after a bit more googling and some trial and error i can now get GPSD to get gps data from the unit! :D

Many thanks to DeeJay for the help!
For those following the thread I'll put everything into a logical order for you to follow:

Plug the USB GPS into the pi, you should be able to see it detected in:

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sudo lsusb
Mine came up as
Bus 001 Device 004: ID 1546:01a6 U-Blox AG
Using

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dmesg | grep -i usb
I (DeeJay) established that the GPS device was paired to:
ttyAMA0
You can check your GPS data feed by using the CAT command and viewing the GPS data directly by typing

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sudo cat /dev/ttyACM0
Next I piped the GPS feed into the GPS demon - gpsd by

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sudo gpsd /dev/ttyACM0 -n -F /var/run/gpsd.sock
I had to ensure that the -n flag was present in this command, as trying without the flag resulted in a time out.

then just to be safe I killed the gpsd and restarted it

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sudo killall gpsd
You should now be able to use

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cgps -s
to view the interpreted GPS data coming from your unit.

Many thanks to DeeJay for your help with this!

Mathew

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DeeJay
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Joined: Tue Jan 01, 2013 9:33 pm
Location: East Midlands, UK

Re: Unable to find USB/TTY GPS unit

Thu Sep 19, 2013 6:01 pm

I am pleased you are up and running. (or is it jogging? cycling?)

And thanks for the summary for the benefit of those who may find and follow this thread in the future.
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AndrewS
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Re: Unable to find USB/TTY GPS unit

Thu Sep 19, 2013 8:37 pm

Matthew - looks like you need to edit your instructions to replace an occurrence of ttyAMA0 with ttyACM0

jtgsy
Posts: 4
Joined: Tue Sep 20, 2016 8:01 pm

Re: Unable to find USB/TTY GPS unit

Fri Oct 21, 2016 8:32 pm

hi

my ublox 7 USB device is showing as /dev/ttyACM0

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[    3.862152] usb 1-1.2: Product: u-blox 7 - GPS/GNSS Receiver
[    3.862164] usb 1-1.2: Manufacturer: u-blox AG - www.u-blox.com
[    4.594271] usbcore: registered new interface driver brcmfmac
[    4.668109] cdc_acm 1-1.2:1.0: ttyACM0: USB ACM device
i can cat the device and use gpscat to see the NMEA but unable to get gpsd and cgps to work with it.

have tried

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sudo gpsd /dev/ttyACM0 -n -F /var/run/gpsd.sock
james

jtgsy
Posts: 4
Joined: Tue Sep 20, 2016 8:01 pm

Re: Unable to find USB/TTY GPS unit

Fri Oct 21, 2016 8:36 pm

further to the above

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[email protected]:~ $ gpspipe /dev/ttyACM0 -r
{"class":"VERSION","release":"3.11","rev":"3.11-3","proto_major":3,"proto_minor":9}
{"class":"ERROR","message":"No such device as /dev/ttyACM0"}

jtgsy
Posts: 4
Joined: Tue Sep 20, 2016 8:01 pm

Re: Unable to find USB/TTY GPS unit

Fri Oct 21, 2016 8:50 pm

edit the /etc/default/gpsd/ file

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# Default settings for the gpsd init script and the hotplug wrapper.

# Start the gpsd daemon automatically at boot time
START_DAEMON="true"

# Use USB hotplugging to add new USB devices automatically to the daemon
USBAUTO="true"

# Devices gpsd should collect to at boot time.
# They need to be read/writeable, either by user gpsd or the group dialout.
DEVICES="/dev/ttyACM0"

# Other options you want to pass to gpsd
GPSD_OPTIONS=""

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