v1 hacking: hardware and software

[tedder]

Placeholder for a v1 discussion, spinning out of #12.

[tedder]

Fred, @fbretmounet, posted:

@kruton , I'm trying to replicate your findings on a first generation feeder. If I followed you correctly, point mqtt-a01.arrowconnect.io to a machine on your local network (I use pihole and love it!). Start a mosquitto broker on that machine and the feeder should start publishing messages to that broker? If so, I've spent some time on it and it seems gen 1 is not mqtt-aware :-(

[tedder]

kruton:

@fbretmounet do you have any pictures of the electronics on the V1 feeder? It seemed like all the smarts may have been in the bowl.

[tedder]

fred:

@kruton , yes it is under the bowl. I took the attached pictures when I opened it a few weeks ago. Let me know if you want more pictures!

[tedder]

kruton

Looks like this might be a design based on electricimp imp003. Are there any pictures of the overall board? I'd be more interested to see if there are pads to connect debug cables as mentioned in their documentation.

The other chip is a flash part.

It looks like electricimp has a lot of repositories on GitHub which has all the parts for implementing a server and communicating via their optical BlinkUp system.

[tedder]

fbret

Here are picture of the top of the board and a picture of the back only showing test pads. I did not find obvious jtag or serial pads. I did not find standard debug documentation from electricimp. :-( https://developer.electricimp.com/hardware/imp/imp003pinmux suggests quite a few different combinations for serial... I guess I could try every one of them...

[tedder]

me

When the gen1 discussion came up in the past, it sounded like the Imp was shipped in "production mode", locking down a lot of the debugging and such.

[tedder]

fbret

I hate it when manufacturers do it right! The alternative is to rebuild my own board :-(

[tedder]

@brbeaird

Such a bummer. You guys are doing great work - hate that I can't easily apply this to my V1. Honestly hate the idea of just chucking the whole thing into the trash, but I don't know what else I'd do with it. I already bought a PetKit feeder, which seems to do the job just as well.

[tedder]

kruton

I don't know what the V1 looks like on the network. I would suggest trying to do packet captures of what it's sending across the network (or trying to send now that PetNet's domains are defunct).

[keytheengineer]

It looks like the V1 has an open pad for a micro USB on the back. Has anyone messed with that?

[jmunowitch]

If anyone on the dev team needs a petnet v1 for this task, I have an extra in San Francisco.

[techydude]

hi everyone,

i've been 'in transit' for the past 7 months, so only seeing this repo now, and I'm on the eve of getting my gen1 back in my hands (it's been in storage/on a ship since Sept2020), and am open to helping get this project working on gen1 hardware.

the possibility of developing an alt MCU/wifi board (a replacement for the Imp) is not out of the question for me, nor even replacing the entire electronics; i'm already in the early stages of re-braining one of the 'Wopet' feeders with a Particle Boron, because its non-IoT UI is horrid, like programming an 80s VCR. but it's mechanics are shitty, compared to the Petnet gen1's mechanics which seem pretty reliable and long-lived to me (opinions about gen2's mechanics seem to vary quite a lot!), so it may be a better use of my time to target new hardware to gen1/gen2 Petnet instead of the Wopet...

so, are there any other developments re gen1 I should be aware of? given a new brain, is there much interest in getting gen1 working with this repo that you know of? (i only just discovered this repo, so I'll have a poke around some more).

[dorfman2]

@techydude I'm about to start the process of just replacing the board, and am happy to help. I have limited experience with PCD design, or even better, if we can just drop in a ESP8266 or similar.

My goal would be to capitalize on all the hard work done here with the app if possible. My question:

What board/setup would be able to talk to the app that has been developed here?

[techydude]

@dorfman2 Thanks for replying!

Since my 1st post, I've proceeded on the assumption (from other's investigation above) that the electricIMP on the Gen1 is locked & not reprogrammable, though not confirmed this myself.

I've looked at the Gen1's mechanics and the electrical peripherals, and discovered they're almost identical to the cheaper/nastier WoPet I was originally targeting with a new brain/PCB (tho of course the PetNet has no UI other than the manual dispense button with 2-colour LEDs, whereas the WoPet has an LCD + buttons).

Better yet, I think it will be possible to make 1 PCB design with 'snap-off' section(s) that will allow that 1 PCB to fit either PetNet gen1 (no LCD or buttons fitted), or the WoPet (with LCD & buttons fitted). So that's my plan at this point. I hope to tackle that over the coming month. Of course I'll be posting it here on GitHub so others can make it if they wish. Whether I go as far as having a batch made and selling them (e.g. Tindie) depends on demand, and so far you're the only one who's replied :-), and admittedly the PetNet Angst was a 2020 thing, so I might've missed the wave there, who knows...

I've no idea if anyone's interested in new hardware for PetNet Gen-2? It's great that this repo will work with Gen-2's firmware as-is, but there's little to no room for modification. I'd need a few photos & dimensions of the Gen2 board to work out if I can kill 3 birds with 1 PCB... ;)

Anyhoo, I was planning to use a Particle.io Argon board (wifi + BT; BT likely not needed), as the Particle cloud can be used for dead easy firmware updates without needing to add any of one's own infrastructure, whilst still having an open LAN/internet connection for accessing application support (i.e. this repo). But I'm also OK with putting in an ESP32 variant, if there was a decent reliable OTA-firmware-update mech available? I'm not up-to-date on that scene, so open to suggestions!

[dorfman2]

@techydude Sound fine to me! My background is a bit more on the DIY hardware side, so this sounds more refined that my solution of stick a Raspberry Pi in it. Are you on the Tedder slack to talk about this further?

[tedder]

sent.