Fwd: feedback on experience with OSX packaging

Jef Driesen jefdriesen at telenet.be
Fri Oct 5 07:51:32 PDT 2012

On 2012-10-05 06:42, Dirk Hohndel wrote:
> Amit Chaudhuri <amit.k.chaudhuri at gmail.com> writes:
>> I try an connect my Suunto Vyper Air using USB cable.
>>   Device is powered down.
>>   Insert cable in to Mac Book
>>   Insert into Vyper Air
>>   Device reports switched into Data Transfer mode (i.e. on screen of
>>   dive computer).
>>   Menu option Log | Download from DC does nothing for circa 20 sec
>>   When it brings up Download from Dive Computer dialog it has 
>> remembered my
>>   last choice (Suunto Vyper Air) and device name - 
>> /dev/tty.SLAB_USBtoUART
>>   error message below is Unable to open Suunto Vyper AIr
>>   (/dev/tty.SLAB_USBtoUART)
>> I have Suunto Dive Manager installed on the same machine and it will 
>> talk
>> to my Vyoer Air dive computer. However, subsurface will not yet 
>> recognise
>> the device. Error message from subsurface is:
>> Unable to open Suunto Vyper Air (/dev/tty.SLAB_USBtoUART)
> So this means that you most likely HAVE the correct kext installed
> (otherwise the Dive Manager wouldn't be able to talk to the Vyper 
> Air).
> My guess would be that the device name is wrong, but I'm on a plane 
> and
> can't even Google for this. Jef - any suggestions (as this is clearly
> libdivecomputer territory)?

The /dev/tty.SLAB_USBtoUART device name indicates you have some Silicon 
Labs CP210x based hardware. The official Suunto cable has an FTDI 
usb-serial chip. So unless you have one of the third-party cables, that 
device name is likely incorrect. You mention a Mares Puck, and that one 
does indeed need the CP210x driver. So maybe that device name comes from 

What output do you get when you run this command in a terminal (with 
your dive computer connected of course):

ls /dev/tty.*

>> With subsurface running and the usb cable plugged into the dive 
>> computer
>> the unit switches into a mode which writes "data transfer" into the 
>> display
>> but that's about it.
>> Any advice on troubleshooting much appreciated.
>> I have not added any specific drivers (perhaps naively) I assumed 
>> that this
>> might not be necessary given the SDM4 installation is operational.  
>> I was
>> also unsure about the section of the documentation which mentions 
>> manually
>> hunting for drivers.  How would one know that Mac_OSX_VCP_Driver is 
>> right
>> for the Mares Puck? Is it also right for Vyper Air?
> Great question. Again, maybe Jef has a pointer to his documentation 
> that
> would clear that up?

Have a look here for info on the drivers:


As far as I know, the Vyper Air automatically goes into transfer mode 
when you connect the usb cable, even when you don't have a driver 
installed. So that doesn't tell much.

I need to see a logfile to tell what is really wrong. Is it failing to 
open the /dev/tty.SLAB_USBtoUART device node, or is the communication 
with the dive computer failing. I can't tell without further info.

Can you run the "vyper2" test application and send me the logfile? Some 
instructions are available on the libdivecomputer website:


>> I would also like to get this working with my Gekko, so any 
>> secondary
>> pointers there would also be welcome.  For info, I called Suunto 
>> customer
>> services to ask them about accessing the dives on my  Gekko (now 
>> that I
>> have a shiny new Vyper Air I thought they might be a little helpful; 
>> sadly
>> wrong). So I suspect that if you can craft packaging and docs to 
>> explain
>> how to get data from Gekko's onto subsurface you might tap into an
>> interesting niche.  Many divers starting out in the UK in the last 
>> few
>> years will have been brought up on Gekko and would be delighted to 
>> work
>> around the unhelpfulness of Suunto in this matter.
> I know this worked with the Gecko for me (when I still had it).
> And while it can be hacked to work with the Suunto Dive Manager 
> software
> I don't think that hack is required to work with Subsurface...
> Let's figure out the correct dive to use and take it from there.

No hack is required to download from the Gekko with a libdivecomputer 
based application. Only Suunto Dive Manager has this silly limitation.


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