TL;DR: Checkout my forked https://github.com/florind/TinyGPS, adding GLONASS and NMEA 3.x support and that it’s fully compatible with the original TinyGPS and Arduino.
It’s been too long of a dry streak on my blog (four years!) but in the mean time I’ve been actively working on several projects. About 3,5 years ago I have reconnected with hardware engineering, a hobby of mine ever since I was a kid.
I am integrating GPS in one of my Arduino-compatible hardware projects and I’m using a Maestro Wireless part, called A5100 that notably comes with GLONASS support (the Russian constellation of GPS satellites).
There’s some pretty nice GPS support in the TinyGPS project but it lacks any of the advancements in the field such as NMEA v3.0 or support for additional constellations. This means that some good data is ignored when parsing NMEA sentences from devices such as the aforementioned A5100.
I have therefore worked on an update to TinyGPS to incorporate some missing support that I published here https://github.com/florind/TinyGPS. This is a drop-in replacement for TinyGPS and backwards compatible with any NMEA compatible GPS receiver integrated with your Arduino.
The full complement of details is in the Github documentation. Notably, this update adds GLONASS support and exposes some interesting data when not tracking:
– Date and time
– Satellites in view
With this data we can build GPS user interfaces containing more advanced data. Here’s one I’ve built on a small Sharp ePaper LCD model LS013B4DN04
The left screen capture shows the GPS device searching for a fix. There is a valid date and time shown on the top as well as the satellites in view: 4 from the GPS constellation and 5 from the GLONASS constellation (having PRNs 65 and above). Each satellite specifies its signal/noise ratio in dB (abbreviated to ‘d’ here).
NMEA IDs in depth here: https://github.com/mvglasow/satstat/wiki/NMEA-IDs.
The screen capture on the right shows the GPS device tracking. Satellites in view are still showing although only three are participating in the solution. Shown is also the GNS mode indicator, the “AN” string, indicating that only the GPS constellation is used in the solution in this moment.
If you wonder what the e210 is, it’s the horizontal dilution of precision, HDOP. Divide by 100 to get to the ranges specified on wikipedia.
A5100 and other modern GPS parts promise out of the box support for Galileo who will become operational in 2016 and BEIDOU, already operational in Asia.
As this update only adds GLONASS support, feel free to add support for others if they’re available in your area (BEIDOU for now).
TL;DR: Go for a VPS. I now use Digitalocean, they’re awesome.
Selecting a web hosting provider is a tough job for any web developer that wants to put a Java/JEE web application online. The choice is much simpler when it comes to publishing a PHP web site and there are a load of cheap (and sometimes quite reliable) PHP hosting providers to choose from with LAMP being the de facto standard in the web hosting world. But when it comes to Java hosting providers the picture becomes blurrier. The common thing that all these environments need is a Java container. The most popular choice is Tomcat but there are providers that use Resin, Weblogic or Websphere (the latter two are full fledged JEE containers).
With the raise of lightweight J2EE servers started by the Spring folks, a little revolution began in the Java world: running enterprise-grade JEE webapps without the need for an EJB container; a servlet container is enough. Tomcat should fill the bill for just about any Java web application that doesn’t use EJBs. The advantage that comes from running a servlet container is the smaller footprint compared with an EJB container. This is critical when it comes to selecting hosting environments since you’re paying for resources (especially RAM) that have to be sized to accommodate the memory requirements of the web application.
Self hosting: Home-based dedicated server (near $0)
You can use your home internet connection and a PC where the web container runs and deploys your web application. There is an obvious advantage since the server is physically located close to the development team: complete control and physical access to the machine. The other big plus is the price: you’re already paying for the internet connection and chances are you already have a PC that can be transformed into a server. And chances are that you already have a development environment that can be the basis of the production deployment. Here are the shortcomings:- Bandwidth limitations: the webserver where the webapp lives will upload content to the web browsers that access the application. The upload bandwidth is smaller than the download bandwidth and will result in longer load times for web clients.
– Some internet providers cap the internet traffic so you may run beyond the limit.
– You may violate contractual obligations you agreed with your Internet provider by running your own web server.
– The internet connection is not reliable: provider’s downtime directly translates in downtime for your webapp.
Continue reading “Choosing a Java hosting provider”
One benefit of owning a Mac is that you’re part of a never ending soap opera that Cupertino carefully directs. Sometimes the drama has bright spots such as the Mini Display Port story.
The MDP became quite the feature story when Apple decided to scrap the DVI port on its new unibody lineup. I didn’t pay too much attention initially but since the Macs are so media friendly, I found myself wanting to plug it into a TV basically the second day after I bought it. Bummer. The only way is MDP. A quick look on the net left me with a bitter taste. Apple Store sells a DVI adapter for $30 and on the Apple forums people were begging Monoprice to start producing a ceapola version of the adapter. Only that Apple owns the MDP spec and therefore not doable. And there’s no MDP->HDMI adapter, the one that I really craved for.
A short few weeks later on Dec. 1st, the drama registers its first break. Apple suddenly announces no-fee licensing for the oh-love-me adapter. Things heat-up, some suggest petitioning the cheap cable producers to start making the damn thing and there’s hope. I started dreaming of an adapter that I could buy for peanuts. Well, my dream came true today: Monoprice is making it. Still not listed (I could only spot a $15 MDP to DVI adapter) but most likely in the works at Monoprice. You rock guys. I’m guessing a similar price range (1/2 off Apple’s own) should be enough to get the Mac guys’n’gals skip a pizza delivery and snap it. But we know you can do better than this. Monoprice, show us what you’re made of. You’ve done it before with dirt cheap HDMI cables. You can do it again.
I’ll take 50.
Update (Feb.16): They’ve done it. Available on or around March. 15: Order here