Back in January of this year we described the GPS Car Computer, a project that used a low cost GPS module to provide a variety of data for the motorist.
The project essentially consisted of a microcontroller, a display and a GPS module and it was obvious from the outset that it could be used for other applications.
The GPS Boat Computer in action on the water, in its spray proof housing designed by Nigel Hall. It is showing the speed (in knots), a compass needle pointing in the direction of north and the boat's current bearing (159°). (courtesy Nigel Hall)
One reader, Nigel Hall of Dee Why in Sydney (himself an avid boatie!), was quick with the suggestion that we should make a nautical version. Nigel then went on to put in a lot of his time into defining a typical set of boating requirements and testing the final product.
So here is the result – the GPS Boat Computer, a small electronic device intended to provide the weekend boater with a host of useful information.
It will show your speed in knots, your heading, fuel consumption rate and the total amount of fuel consumed. It will also show your latitude and longitude and a compass needle pointing north.
Possibly the most handy feature is the ability of the GPS Boat Computer to memorise up to eight of your favourite fishing or diving spots and later guide you back to the exact same spot – even if it is in the middle of the ocean.
This project illustrates a trend in modern electronics… the use of intelligent and general function devices that can be reprogrammed to suit a variety of purposes.
An extreme example of this are the Mars rovers Spirit and Opportunity. They have been reprogrammed many times to cope with the various conditions and terrain that they have met during their exploration of the red planet.
In a similar vein the GPS Boat Computer uses virtually the same hardware and circuitry as the GPS Car Computer described in January and February 2010. The major difference is in the firmware which completely changes the character of the device.
You do not need a PIC programmer for this change in personality; the new firmware can be loaded via USB from your computer and the Car Computer will become the GPS Boat Computer.
You could, if you wished, then load the Car Computer firmware (also via USB) and flip back to that personality. In fact, you could drive to the marina with your GPS Car Computer, load the new firmware (it only takes 20 seconds) and sail off with your GPS Boat Computer!
This also means that if you want to build this project from a kit you can simply buy and build the kit of parts for the GPS Car Computer (from Altronics) and upload the new firmware to turn it into a GPS Boat Computer.
The only thing that you might need to do is consider a different enclosure – and we will talk about that shortly.
Using the GPS Boat Computer
The GPS Boat Computer is quite easy to use. You have a number of screens that show useful information which you select by pressing the UP or DOWN buttons. These buttons will wrap around the available set of screens when you have reached the end. When you turn the GPS Boat Computer off it will remember the last screen and will automatically return to that when power is reapplied.
All screens have something that can be configured or changed. For example, when the clock screen is showing you can set the time zone. To change a setting you press the SET button and then use the UP/DOWN buttons to adjust the value. Pressing the SET button a second time will save the value and either take you to another option or return to the main display.
Some options are in the form of a question. The screen above shows a typical example of this and when presented with this you select YES or NO by pressing the UP/DOWN buttons then press the SET button to confirm the selection.