Choosing the right chip to work with SureFeed cat feeder

My cats have food bowls programmed to open for each of their regular pet microchips. Each bowl can be also be programmed to open for multiple chip IDs. I am interested in implanting and RFID in my hand to open the bowls without having to put down all of the food I’m trying to serve them while I push the manual open/close button.

I would like to go ahead make clear that I am not very tech savvy, but here are the things I’m thinking about in these early stages of this idea.

First, I looked at the frequencies of the common pet microchips in the US. They are 125kHz, 128kHz, and 134.2kHz. I have not called SureFeed to see the range of frequencies the feeders read, but in this range I see the xEM with a frequency of 125kHz.

Then I thought about the ID number that the feeder gets from the pet’s microchips. It sounds like the common pet US pet microchips have either a 9, 10, or 15 digit ID number. From what I read, I believe the xEM could be cloned with an appropriate UID. Is that correct? I know the xM1 has a writable UID, but the frequency is 136.56MHz.

Is my thinking on the right path? Does anyone think this could work? This whole thing started with a dream I had two nights ago where I had incorporated a regular pet microchip into a ring. My idea morphed into this because I don’t like to wear jewelry, but I can go back to that plan if this new idea is a bad one…

Thanks to any and all for your thoughts and advice!

Interesting application!

The xEM will not likely work. Pet chips in the EU are ISO standardized, while the US is a free-for-all of mixed protocol chips… but EM is not one of them. You will likely need an FDX-B chip, like our xBT … however because the US is the “wild west” when it comes to pet chip protocols, the best course of action is to call SureFeed and tell them you are getting another pet and you need to know which chip to get the pet so it will be compatible. From the brands they name as “compatible”, you can either 1) determine if the xBT will work for you, or 2) you can opt to go to a vet or animal shelter and see if they will sell you the injector so you can inject a pig or some other farm animal too big to bring in, and arrange to have it installed in your hand.

I glanced at the website and the user manual and the only mention of compatibility is “Compatible with all identification microchips worldwide & SureFlap RFID collar tags” … so if I had to bet, I’d say the xBT will work just fine for this application.

To be honest though, I don’t understand why they didn’t put an easy pushbutton release for the flap… i mean, how are you normally supposed to get into it?

Thank you so much for your insight and information, amal!

With the minimal monetary investment involved with your xBT chip, I may order one and see what the feeders think about it. I am sure I could obtain a pet microchip, but I worry too much about something that was intended to be injected into a being that is “just an animal.”

I do understand the risk of injecting any foreign object into my body, and that this chip has not been tested or certified by any government regulatory agency for implantation or use inside the human body. :wink:

That being said, the testing of the products on your site gives me enough comfort to give it a whirl, if the bowls cooperate. My only hesitation is the BioBond cap on the cBT…but I’m sure we can still get it out of there without too much trouble if we need to. For a pet microchip, I’ll probably revisit the jewelry idea. I’m actually reconsidering the regular old pet microchip our kitten is getting next week. If mine works with the feeders, I might just order one for him, too!

And the bowls do have a button that is easily accessible, but trying to feed three cats three different types of food at the same time (without any of them snatching the others’) is so hard to do with just two hands! These feeders have been a lifesaver (literally!), and I will probably always use them. I’ve been keeping an extra tag in my hand when I feed them, but this would be so much easier if it works! So this isn’t TOTALLY a crazy cat lady idea…right? :wink:

Please ignore typos- specifically the cBT one. The x was too close to the c, and I didn’t notice that I typed that instead. :frowning:

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I wouldn’t do that actually… The US is pretty crazy with it’s approach to these things and there is no guarantee that the xBT will be readable by any of the vets or animal shelters in your location… these things tend to be clustered… some cities use Avid chips, others use the “Trovan” or “FriendChip”… there are other options out there too, and each uses their own protocol. I’ve seen pets get moved from one city to another, and when they are taken to a vet the vet scans them and says “this pet doesn’t have a chip” and the owner says “oh i thought it did, let’s chip it” and the poor thing ends up with 2 or 3 chips in it. Admittedly, this isn’t so common now since most vets and shelters buy “multi-chip readers” that can read most types… but still your best bet for getting a good read on your new pet is to get one from the local vet put in.

The EU has done things the right way… they went with an ISO standard protocol for pet chips, so all manufacturers must comply and thus, all pet chips are readable by a single standardized protocol.

Sorry to drag that thread out of retirement, but for the record, it will: Sure products read EM chips also. At least they read my EM4305 - which I believe the xEM can be configured to emulate.

In theory, they should also read EM41xx and 42xx but I haven’t tried. Matter of fact, I’ve just shot Sure an email to ask, because I happen to have a few projects in mind involving hacked SureFlap catflaps.

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Here’s the reply from Sure’s tech support:

it has to be 64bit Manchester Encoded, which is an option (A6) on the EM4200


yep the T5577 can do this, but it’s not the default configuration we send them out in… they are set up with a 40bit ID, but changing it is possible with a proxmark3

Well, today I found out the reply from the Sure tech support guy is BS.

I figured I’d reprogram the xEM in my foot to have a 64-bit UID this weekend, so that it’ll be compatible with the SureFlat catflap I ordered when it gets here.

So this morning, I dragged out the Proxmark3, installed the ProxLF antenna and proceeded to find the ideal spot on my foot. But, being a careful man, I wanted to compare the range with the EM4305 in my hand that works with Sure products. And as I re-read the EM, I realized it has a 40-bit UID programmed in!

So Sure products definitely should work with stock xEMs. So much for asking Sure…

Incidentally, it’s not the first time I try to get technical details from companies that don’t even know what their own products do: that’s what happens when you use ready-made modules and libraries from third-parties. So it’s up to the user to discover it. I have a really quite expensive bluetooth FDX-B reader on my desk here that the salescritter swore on his mother’s life would let me access the application bits in the FDX-B telegram, and that doesn’t - and I’m quite pissed off about it.

But I digress…

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I got one of the 2 SureFlap catflaps I ordered in the mail today. Why I didn’t get both at the same time, god only knows…

Anyhow, it’s defective. It won’t read anything: neither my sample cattle FDX-B ear tag, not my EM implants, nor the supplied cat collar tags. So it’ll be going back for replacement.

However, the interesting bit is this: both supplied tags are EM4102’s with 40-bit UIDs.

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I’m so interested to do some testing with the proxmark3 on some wiegand readers to see which bytes it is truncating… MSB or LSB… and I am wondering the same of the cap flap… you could use the proxmark3 to program a T5577 to find out if it really is only reading 40 bits or if it’s reading more (if more are available) and basing it’s access authorization on that or not. so many terribly terribly designed RFID things out there it really is upsetting to me.

I’ll try that when I get the second catflap. No need to program anything: the PM3 can simulate EM tags (I think? Can’t be bothered to check right now).

It might be interesting to know if it only uses a few digits out of a full UID; On the other hand, if it does, it’s only a catflap: it’s not trying to deny entry to evil black hat pussies :slight_smile: But I’m interested because if I repurpose it to open more serious stuff with my own implants, then it becomes more of a problem.

Good thinking. I didn’t consider this.

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Old post, but a KISS-solution to this is to attach a keyfob/RFID-chip to the measuring cup.

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