Hi all, I'm wondering if anyone has had success, or can at least point me in the right direction, to interface Arduino with the coin mechanism from a vending machine.
Right now I'm not choosy—ideally it would be one that could accept any type of coin but I can work with any, analog or digital.
big thank you in advance.
I haven't used an arduino for interfacing with one, but I have done it on other hardware. It's not difficult to find coin acceptor that uses serial--most of them use a subset of the CCTalk protocol, which is very simple and should be pretty trivial to implement on an arduino. The protocol is also popular for bill acceptors, so you could very easily support them, too. Pyramid Technologies, Inc. (who I reccomend if you are interested in bill acceptors) have a really easy to follow PDF, but it pretty much limits itself to what you really need to know to do the interfacing. The official CCTalk documentation is available from Money Controls at cctalk.org. It's probably a lot more than you'll ever need.
The coin acceptor that I use is the USB version of the EMP 800 from wh Münzprüfer Berlin GmbH], but by USB they mean serial + an FTDI chip, and I'm pretty sure they have a straight serial version (not sure about TTL levels, though, so you may need to pick up one of those rs232 shifter kits from sparkfun). It's an electronic selector, which means much more accurate, but also more expensive.
Just stay away from the MDB protocol and you should be okay.
Apparently you're not allowed to put links in your first post, so here is some stuff that was going to be links:
CCTalk
Pyramid Technologies, Inc.
PTI's protocol description
Money Controls
EMP 800
wh Münzprüfer Berlin GmbH
Thank you for those links. They will provide me with some research joy too.