BoatBus, an Open Hardware and Software Project
A chronicle of my nerd hobby
Sure, there is open software out there. Linux comes to mind. And there are even a few open hardware projects. This is intended to be a completely open embedded system. Schematics, source code, and PC layouts are all available for you to look at, use and possibly contribute to. Most businesses need to keep designs proprietary in order to maintain a competitive advantage. This is not a company, it's a part-time endeavor and I am doing it purely for my own enjoyment. And I wish to share it with other people.
What BoatBus is in the most general terms, is a system for collecting data from the environment, and displaying it for humans to read. It Also allows the human to control some aspects of the environment. The first system is intended for both home and boat use. Common functions between a home and a boat: collecting weather and environmental data, power usage, controlling lights and sound, displaying in several convenient locations.
I'm Dave Erickson, an EE. I've worked at several companies in the Boston Route 128 area since graduating WPI in 1976. Two years at HP medical, then three at a startup: Octek, where I was half of their consulting group, and where we designed just about anything for just about anyone. Then Datacube as Director Engineering for 15 years, doing real-time Image processing. Then 4.5 at Analogic as Chief Engineer of the Test and Measurement division. Then to Zoll Medical, working on Defibrillators, then a startup stint and curently at Teradyne, where we make big ATE machines. My skills are mostly analog and digital hardware design, but along the way I began doing assembly programming, and then C. At home, I build electronics for home and boat. I like to mix analog and digital hardware design and software in a complete system with sensors, data acquisition, processing, display and a bit of communications thrown in.
For the past few years I've been working on a networked display and data acquisition system. I did the first generation of a similar system about 10 years ago. It used a surplus LCD panel, a 68hc11 micro, and a bunch of code and custom hardware. It was a single box system designed to provide my boat with a bunch of marine-type data: wind speed and direction, boat speed and direction. It also provided rudimentary navigation by maintaining a dead-reckoning track.
The name BoatBus is my generic name for my old boat project, BoatBus. While it worked OK, it was really a functioning prototype, and had some limitations. In reality it was not a bus. It consisted of a single box containing all the signal conditioning, acquisition, processing, and display circuitry. This made it larger than I'd like a display to be. It also meant that all the low level analog sensors had to be wired directly to the main box. I used the system for two years aboard my old boat. When I moved to a newer, larger boat, I never installed it. It's size was inconvenient and not really worth the hassle to wire it all up. Plus, GPS now offered most of the nav features that BoatBus had. Also it had no expandability: to add a new sensor or a second display required significant re-engineering. But it was a good first step towards the ultimate system.
The old surplus LCD display was a Hitachi HD215XP. It was not backlit, and had the annoying habit of completely blacking out in the heat of direct sunlight. I learned not to use a first generation LCD outdoors. Also the form factor required a large enclosure, and there is no room for large boxes in the cockpit of most boats.Here are the innards: the 68hc11 processor board on the left with the original Actel LCD1 controller. The analog board is the real PC board on the right. I used 96 pin DIN connectors to connect them together. Tucked in the upper right corner is a the +5V switching power supply which is a National evaluation board. The entire system drew about 120 mA current from +12V
The +12V power and the sensor wiring comes from the 25 pin D cable on the lower right. It connects to this breakout box with connectors for the various sensors
I decided I'd also like LCD displays at home, to display weather, house power use, and to control my house-wide stereo system. I began a wish list of features for the boat and for the home.
BoatBus 2 DisplayHere is the hardware for the display node. I needed something to show for the effort and thought so far, so I installed the prototype hardware in an enclosure, along with a QVGA LCD panel. Here is the proto of the AVR Mega128 processor with an LC10X type LCD controller. The empty sockets on the top left are from the old 68hc11, SRAM and EPROM that I removed. The Mega128 is on a prototype adapter from http://www.devrs.com/store. In the upper right are the LCD controller FPGA, 8 pin config EEPROM, and display RAM . The IC and caps on the right are the V- power supply for the LCD. JTAG ICECube for development is lower right.