On 20 October 2013 10:24, Chris Green cl@isbd.net wrote:
The difficulty is mostly in the nitty gritty hardware intefacing, getting voltages into the device in such a way that it's unlikely to kill it if/when spikes and noise come along.
^^^ This!!
Currently on the boat I have an ancient 7" eeePc with a 1-wire to USB interface and sensors on the 1-wire bus. 1-wire is good for various measurements but doesn't seem to have voltage sensors. In fact *nothing* seems to offer decent voltage measuring sensors, there's lots of things with "A2D inputs" but nothing that offers an 'outside world facing' capable one.
In the absence of any knowledge to guide me elsewhere I'm looking at I2C. I don't know the size of your boat though so it might be pushing the limits on i2c (I've seen references to people running it over CAT5 to distances of ~20m - not bad for a bus designed for inter-chip comms).