this is for a project of a radio frequency switch with nfc control.. I have not yet the implenter technology for the PN532 (0.2mm space between pins). So I'll see if the mechanical engraver can achieve the board or if I should use a QFN32 adapter -> DIP 32
I also working on a simular project using a chip TRF but it is related to my job and I can not disseminate plans ... sorry!
Hi @gth, 'marker' is from the origin of the things when they were originally used to throw a paint pellet at a cow and mark it. America!
In Australia there are so many people who are rabidly anti-everything that it's common to continue referring to them as markers and disassociate them from actual guns. There's a lot of backstory there, and only recently being allowed to have some things at all, like the Tippmann A5 which is still illegal in some states I believe.
My antique one is illegal in Victoria because it has 'the same profile as a longarm' because the magazine runs alongside the barrel instead of being a clip on hopper.
On that subject, the reaction when I presented the A5 to be registered at the local police station was exactly that. The female hossifer actually backed away, saying Wtf a lot. It was all a little bit emotional. This because legally I must state my intention, 'officer, I have a firearm in this bag to be registered, may I place it on the bench and open the bag for you?' at which point she is expecting a gun, not a marker and mistakenly sees an MP5 instead of an A5.
Anyhow, it would need to be fail_lock to be a workable solution for a firearm, otherwise just popping the battery would be enough to bypass it. I'm thinking of something along the lines of a pin that jams the mechanism the someway most safety mechanisms work. Then removal of that for a period when the firearm is held by an authorised ring wearer.
It would mean that the battery would run down fairly quick and that any issues with the mechanism would render the firearm inoperative until it was repaired, bur I think that's the only realistic way to do it.
That's an interesting one @Steve-Peake. It's a shame they don't have more of a description/explanation of those two items. If there's an NFC tag located in there somewhere it might be for your personal details perhaps?
One thought would be, since NFC tags are a passive device, to add your details to an NFC tag and lock it permanently read only - then secrete it somewhere that it can be read but not accidentally.
There's no better proof that something is yours than having your name digitally hidden in the item eh.
A rasberry Pi is more expensive and need more power than a classic arduino. I think the better choise is the arduino for that ;)
You can also choose some alternative like MSP430 10$ for the launch pad with 2 MSP430 chip!. It's as easy as arduino to use but cheaper and it's an ultra low power chip.
I just wanted to follow up on John's previous message and specifically the performance with rings. I am convinced that it could be improved by refining the board's antenna's matching circuit. Before the boards get into production I will make sure I look into this closely!
What you could do there is put it in the keyboard so that about 1 centimetre worth of edge is accessible, with the rest under whatever else you've got in there. You'd have to test with your ring to figure exactly how/where you're consistently triggering, with the v3 unit I get good reads from the side within 4mm, following the direction of the antenna loop at up to 10mm and over the center of the board for slightly more distance in the right orientation.
You could also play around with disabling the integral antenna and using your own loop antenna with it.
Most of us have had excellent results with the Elechouse PN532 V3 unit which you can set to connect to an arduino via I2C. This is what I've done in my car starter, and what was done with the desktop logon unit I linked to earlier.
These can be ordered from Elechouse, I wouldn't recommend ebay or any other site as there do seem to be a lot of clones out there that look the same but don't function near as well.
Depending on your programming knowledge or how much patience you have you can set up your arduino sketch to deal with UID only, stored data, or both.