One very important piece of equipment to have with any APRS or packet radio setup is the capability of GPS. This provides tracking of your station in real time as well as an accurate clock fix. As you sit and read this, there are literally dozens of satellites above you right now that provide these services not only for you but for the government and businesses alike.
Chromebook GPS
Out of the box, Chromebooks lack native GPS tracking in comparison to PCs and Macs. Even if you buy a uBlox USB receiver, Crostini (the native Linux environment) is unable to use it. So how can we get GPS on a Chromebook?
Trust me, I've used Android apps and nothing worked. Developer mode? No go either. Despite the GPS dongle successfully receiving and locking on to satellites, I was still lost as could be. Until recently, when I researched the topic once more on an off shot.
How it's done
Well it's easy - GPS receivers are no more than serial devices. They receive what are known as "sentences" that contain geographic information as well as time fixes or time stamps. This is then fed to the computer serially where it can be read in standard ASCII.
Ever since the advent of USB, at the time where the RS232 serial protocol was dying away, manufacturers began to produce chipsets that would emulate serial communication. Examples include the CH340/341, the CP2102, and the PL2303, just to name a few.
So here's what we'll need to do:
First, pick a chipset that's native AND compatible with the ChromeOS system. These include the ones mentioned above, but for certainty, aim for the CP2102 chipset. I know this works as the Yaesu FT-891 includes it for CAT control. When I initially set my Chromebook up for ham radio, I found that ChromeOS and the CP2102 chipset played VERY WELL. Plug and play, that's it! Below you'll find the pin out in relation to each module:
CP2102 UBlox NEO6M
GND---------------------------------------->GND
RXD---------------------------------------->TXD
TXD---------------------------------------->RXD
3V3DC--------------------------------------->VCC
Really simple. That's all there is to it.
Awful execution
I feel like ChromeOS could've done a bit better with USB forwarding into Crostini. It's a shame that they didn't use the Linux environment to its fullest extent. There are so many Linux packages that can run fine on a Chromebook, but when it comes to external USB devices, things can start to go wrong. And it's here where we can see the Chromebook begin to actually lose its versatility and portability.
I've seen lots and lots of Chromebook users ask if Chromebooks will ever get GPS support in newer iterations - short answer is no.
Google missed a huge opportunity to install GPS on Chromebooks. For just a few dollars per book more, Google could've included a module that would allow users who need GPS access for app development an option for native support. Unfortunately, that didn't happen and this appears to be the only workaround, at least for the Linux option.
Now make certain you purchase a NEO6M module or a GPS receiver that supports serial/UART communication. If you buy a standard USB receiver it won't work. We only need a few crucial lines coming from the GPS receiver to properly send out our position. It's even more crucial to ensure that those lines of data are being parsed correctly whether you're parsing it into Direwolf or Xastir.
From what I can tell running tests on it, the module can work without the external antenna but I'd include it anyway. In the building I work in, on the second floor facing out a window, I can pick up at least 12 satellites, however a fix only requires 3 or 4, which this does flawlessly. However, instead of using a CP2102, I've opted to use an FTDI232 module instead - works great, just make sure that the jumper is on the 3V3 setting to be safe.
Also, be sure to set the correct baud rate for the GPS. By default, it should be 9600, but you could modify it to be 4800, 38400, etc. Just remember that baud rate may vary the data integrity.
Conclusion
Case closed - this IS the way to add GPS to a Chromebook. It works without a doubt AND it works on other computers too. When setting up in Xastir, you can still use a networked GPS (via gpsd).
Now you can fully use amateur radio software on your Chromebook if it requires GPS.
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