Wiegand reader systems… No
Wiegand readers… potentially.
You got to modify it enough… and so far, as I mentioned, it leaves that unreliable, at best. 
I haven’t got it to even read consistently through GPIO so far, so I’ll probably drop that approach anyway.
But I did manage to get it sending modulated pulses. Just way more unreliable, because of GPIO incompatibilities. But theoretically that’s what one would need to be able to use a Wiegand to do a bit more than plain reads.
Ahhh ok, so not simply 
- I’ve seen how impressive even 2008 RFID systems are (credential caching at the reader level, multiple networked systems per building, master cards, actually using a sector on the card instead of just UID) despite using MFC (it was secure at the time I think?). It makes me sad how inaccessible to individuals that sort of thing is except for maybe the Ubiquiti Access control system.
Totally agree with you there.
Even the things I can do on a Wiegand I can only achieve because far smarter people than me have laid out most of the groundwork for me…
Potential with those readers is immense!
If you could just update them to modern security standards, they would be so much better than anything else on retail! 
Yet Wiegand itself took a massive credibility hit when they got exploited… which makes it very comprehensible why they are not investing on a widespread market… 
That’s true, but it wouldn’t solve the fact that the Wiegand protocol is inherently insecure.
Also, if you are going to put that much work into it, then you might as well design something much more secure using the DF2 (you mentioned you had some knowledge of it).
Which is probably a no…
I mean… that is directly dependant on external factors at this moment.
If I have more time to spend in a very specific work project…
& My solicitors continue to astonish me with their boundless incompetence (i.e. my house move gets postponed again)
& I manage to get some consistency in the reads via GPIO (which looks rather unlikely at the moment)
then I’ll keep adding work into it…
Otherwise I will go back into the USB reader approach + straightforward DF implementation.
I want to write something shareable (i.e. non proprietary neither under NDA) on DF, so I’ll end up writing that code either way…
It’s more about what will happen first.
Those are very good pointers! I can tell you’ve put a lot of thought into system failure and security. I have been working on a pcb and code redesign of Paul Walsh’s Simple Sexy module. My redesign is prioritizing IoT and I’m trying to make it a one for all device. I’ll definitely be thinking about redundancy as I continue my coding 
.
I’ve had some of the same thoughts you’ve outlined. With regard to the power failure situation do you think arduino on battery can use as little power as a pi zero while in standby? I wonder how many times an arduino on battery can trip relays before current becomes too weak. I’ll take a look at how access control modules on the market handle power consumption when there is a power failure.
Potentially even less.
Ideally, if you’re going for a single use-case, a dedicated board would be the best case for power saving.
Arduinos consume a bit more but allow you to change and expand on their use-case.
Raspberries consume even more, but allow you to mess around them “in real time”.
I also have plans to get some solar panels hooked up to the no-break and/or batteries, and even thought of hooking up one of those exercise bikes to a dynamo, going to the batteries.
But those are just thoughts at the moment 
A buddy of mine has been very successful with charging battery banks with panels in a window.
That’s interesting!
It’s exactly what I plan on exploring in the future. Assuming I can get the place I’m trying to.
Then it’s double height on the facade (very old factory building repurposed into flats) so I can use the tall windows for the panels.
I’ll have to offer drinks for an electrical engineer first, to get some good Ideas. XD
badges!
Has anyone considered creating a motorized thumb turn replacement for a standard deadbolt?
The idea would be to take off the thumb turn on the inside of the door and replace it with a motorised version (preferably still with a manual thumb turn on it). This would connect to the tailpiece on the cylinder (they seem pretty standard in the US apart from length as far as I can tell).
This could then be hooked up to an XEm Access Controller with the antenna on the outside. The lock would look normal, and still function with a key from the outside or a thumb turn from the inside but would also work with RFID.
This seems like the best overall solution to me as it doesn’t look different, it has manual backup in case of power failure, and can pretty much use any cylinder (Mul-t-lock? Schlage Primus?..)
Anyone? Or is it time for me to start experimenting with servo motors?
Yep this is a retrofit approach and it’s being heavily considered on the side right now. Gimdow makes a descent version of this.
Been meaning to point out the gimdow on Amazon is heavily discounted
I desperately want a way to rig a XAC to trigger it
You aren’t kidding…
let me tell you how much I love the border tax… I can SEE the US from my livingroom window…
Close but no cigar. 
This clamps to the outside of the thumb turn, rather than replacing it and uses their bluetooth app/keypad. I would like to unscrew the thumb turn and replacing it with a motor that attaches to the cylinder tail piece. The motor would then be controlled either by an XAC or potentially any other device that could switch it…
Exactly… What I am looking for is a partial gimdow with just a trigger mechanism so it could be triggered by GPIO or XAC or a hidden switch, or a magnet and a reed switch or…
What do you think the chances are if I tried to contact gimdow, they would tell me if there are contacts I can jump on the board to make it open/close?
I’m sure it’s on the inside portion and therefore would be a security issue
Pretty slim I bet though
…I thought you mailed yours TO Devilclarke?