Finger Print Scanner Module

@ Brett, why not put the socket on the back and free up a lot of space?

I’m curious… In the video they showed a very cool function of being able to download the fingerprint that was last scanned. I wonder if someone could figure a way to rip the scanner out of the wall and retrieve the fingerprints stored within it. :frowning:

The scanner has a command for downloading a template, which is their terminology for a processed fingerprint.

@ Ian: socket on back: Yes, could be done and would save space. Personal preference, I like my modules to sit flat on a desk, and putting that on the back is not going to leave a stable platform imho. What do others think, is size (therefore cost) more an issue than sitting flat?

I will break out the additional pin for intrusion monitoring as @ Louis suggested - anyone feel strongly with placement? I’m staying with 0.2" screw-terminals, and currently staying with mounting them on split sides to allow the most room for mounting screws (I’ve made a few adjustments since they’re not on the 5mm spacing in one dimension - will repost both board renders tonight)

Edit: and on the topic of intrusion and downloading existing fingerprints, yes that is a vulnerability. It may be possible to move the core of the comparison to existing templates back to the Fez if you store the templates locally; or you could consider pushing them down from a defined list all the time. Given the device can only hold 20 prints, I can easily see times that this isn’t going to be enough so it makes sense that the device may have a mechanism to deal with that…

Relevant XKCD: xkcd: Security

@ godefroi, lucky I wasn’t drinking milk when I read that one.

I almost always have mine mounted to a board or something else. Even if the socket is on top it’s almost impossible to get a module to sit flat sometimes because of the cable. I gave up on doing it without a board a long time ago :frowning: Of course, another big advantage to having the socket on the back for this module is if someone wants to mount the module directly to an enclosure. With the socket on top, it would be in the way when you try and poke the scanner part through the hole in the enclosure.

@ ianlee74 -

That is why I propose a Digital Input on the socket for “AutoProtect” but it seems to have no ECHO !

no, it was noticed, acknowledged, and credited. just scroll up a little :slight_smile:

@ Ianlee, do you always have them with a spacer of some kind? I can only think of one device that isn’t “flush” when mounted on my project board, my Hydra - and even then I’ve just left it with some slop on the mounting screws (plastic ones not metal) so it’s not under tension. Oh and my OLED display, that’s not because of the socket on the back :slight_smile: (actually it might be because of that, or something else, but it’s on stands)

Anyhow, the case where the socket is on the back of the long one is quite easy. It’s called “turn it over”. Yes, definitely longer than necessary in that case…

I have a couple of mounting boards (one hydra, one cerberus) that have most of my common test modules mounted on them all the time. As I need other modules for a project, I’ll add it to the board. If/when I go to something more permanent then I usually buy new hardware and keep my test boards intact. The first problem module that comes to mind is the Button module. No way to lay that one flat w/o mounting.

However, I think the case for being able to permanently mount the module is the best reason for wanting the socket on the back. Think about the HD44780 module. Same scenario

Any progress to report?

sorry, work got in the way of other things this week, so won’t get back to this until the weekend but I can give you any of the designs you’ve seen so far and you can get it made at OSHPark in threes - or if you tell me what your ideal style is and I’ll tailor to suit come the weekend!

No problem Brett, its just that this is going to be a very cool module I couldn’t let it slide too far down the page. Socket on the back works for me as I have lots of standoffs (use them with a number of modules, button, camera, Potentiometer, ColorSense, GasSense, LightSense, etc, etc). If there is some way to make the reader detectable that would be great as the extra cost would be worth the benefit.

Duke/Ian/Brett

do you guys have a sensor module yet?

I received one yesterday, and I am trying to verify where pin 1 is on the cable. I bought a
cable from Sparkfun, and I believe the black wire is pin 4.

no, I don’t have one - but I would appreciate a bit of info about the base of the board if I can ? Any lumps/bumps that I need to plan around, or can I assume a clean mating to the board below?

The bottom of the board is even more populated than the top. There is a CPU chip and a few other chips.

The two “ears” are not flat with the bottom of the circuit board, so spacers will be necessary.

Here is a picture of the bottom of the sensor: (If it gets confusing, the picture is upside down)

I have wired up the sensor, with an extender module, and I am able to communicate with it at 9600bps. I have issued a few commands, and they seem to work. I am not using Gadgeteer at this point with my Spider.

I am trying to develop a framework for using the sensor, so things are going a little slow.

But, I was able to turn the camera LED light on and off. :slight_smile:

Great, glad to here it. The idea of touch screen for login is really great.

thanks for the piccie and the detail behind the scenes.

so here’s what I currently think is the most effective mounting strategy for this - to give both permanent mounting capability and also project board mounting.

Given that it will be necessary to use spacers to mount the reader to the Gadgeteer adapter board, there will be no additional stability/rigidity offered if the Gadgeteer adapter board is shorter or longer. So I will just make it long enough to put the socket and headers on and still provide some stability on it’s own when mounted to a Gadgeteer project board.

For mounting the Gadgeteer board to the reader, I will have two holes that a nylon/metal standoff and screw can be used - personal favourites are nylon standoffs that can be trimmed to size by hand. The holes are at 21mm spacing, which is somewhat of a drama since the Gadgeteer standard is 5mm so the centres are 1mm different from those on a Gadgeteer project board.

(** @ Mike, the above is calculated from the datasheet, if you have a Tamiya plate or similar could you see if you can mount the reader successfully to the plate, i.e. a 20mm spacing will work? )

I will add additional width to the board to allow access to mounting holes outside the mounts for the reader - so they’d be 25mm between centres of the holes, total board width 31mm. That way you can mount the Adapter to the reader, then the whole assembly to a project board.

I will make sure I have an additional pin broken out to allow for a tamper switch.

I will use .2" between centres screw-down terminals for the connections. I was thinking about putting .1" header pads between each of these, essentially duplicating the connection, in case people wanted to use actual .1" male headers - does anyone have thoughts about either of these choices??