It's been a year or so since I really looked into other protocols, from memory I disliked CAN because
- Small 8-byte payload
- No auto address enumeration
- 500m total range at ~100kpbs
and maybe other stuff, like the fact that it's not open, Bosch own the rights, now I gather when you buy a transceiver chip the rights are included but that rubbed me up the wrong way I guess.
Ethernet just seems so complicated although I admit that's probably just because I know naff all about it. But doesn't every node have to have a unique MAC address etc? It just seemed like an overkill for a node that interfaces with a single light switch.
With things like MODBUS you have to include a "protocol stack" in your code and then get it working, I think this excludes maybe 99% of Arduino users straight up.
Lonworks is very nice but needs a proprietary Neuron chip.
LIN is limited to 16 addresses and short lines.
The smallest Pyxos node is about 3x3".
Yamar nodes need about 27 components and a proprietary chip.
All the above totally or partially die if the cable is cut or data lines shorted and (I think) they all need a lot of code to be running on the host micro.
You're right though I should be prepared to justify yet another protocol, I'll go back to my notes and maybe write up a matrix of features for all the networks I know about.
As for Kickstarter, I don't know how it's set up. The mob that are running this $1000 scheme (wyolum) only use Paypal but their model is a lot simpler in that they just decide who gets the money and pay them.
KS and others are basically an escrow service that holds the money and either distributes it at the end of the day or refunds it to the donors (or maybe doesn't take it until required but has the CC details so they can). PP wouldn't work because AFIAK there is no facility to hold until a certain date then either forward or refund. I may be wrong, I bought a lens from ebay years ago and the money went into escrow until I said I was happy with the purchase, so there may be an appropriate facility.
How about 1 guy with a credit card machine?
Quite possibly, as long as he can get the donor's approval in black and white somehow so they can't say they never agreed, a bit like the hotel swiping your card so they can bill you even if you skip town.
I for one think there's a real need for this sort of micro-grant, maybe KS et al are fulfilling the need but I'm not convinced of that. I know a lot of them only look at "creative" projects, is there a niche for non-sexy techno project micro-funding?
Rob