reef-pi :: An opensource reef tank controller based on Raspberry Pi.

[hhaase]

Makes sense. If it's just a generic NPN transistor and 10k resistor it'll be easy enough to add, I'll have to see what kind of compact regulator I can find in 10v to keep wiring simple. I still think I'll add an output header location though for additional SCA/SCL driven hardware, with 5v/10v/12v available too.

No promises it'll all make it on this revision though.

-Hans

 

[Michael Lane]

Here's a picture. Just deleted & re-added the probe.

After I type the value in:

After I go up by one:

After I go back down by one:

I haven't seen this behavior. Which browser are you using? I'll try to recreate and solve the bug.

 

[Schreiber]

I haven't seen this behavior. Which browser are you using? I'll try to recreate and solve the bug.

I'm on Firefox with a Raspberry Pi Zero W, running 3.0. I've seen the issue every time I've tried to set up the pH probe, going back to 2.5

 

[hhaase]

I opted, for now, to put all the PWM stuff off onto a separate daughter board. The cost of all the components for the PH probes makes me not want to go through too many iterations. That and doing the isolation and guarding traces on the main board took a while, and I just don't want to tear all that up right now.

So the separate daughter board is going to have the GPIO18/GPIO19 PWM signals, plus the PCA9685PW decoder. It also lets me off-board the 10v regulator for the time being. Still a few things I want to clean up, I'm concerned with connector amperage over the long term in some locations. Should have it ready to order in a couple days.

I'm also going to lock it the feature set for this version too. If I keep adding stuff I'll never get anything built.

-Hans

 

[Ranjib]

I opted, for now, to put all the PWM stuff off onto a separate daughter board. The cost of all the components for the PH probes makes me not want to go through too many iterations. That and doing the isolation and guarding traces on the main board took a while, and I just don't want to tear all that up right now.

So the separate daughter board is going to have the GPIO18/GPIO19 PWM signals, plus the PCA9685PW decoder. It also lets me off-board the 10v regulator for the time being. Still a few things I want to clean up, I'm concerned with connector amperage over the long term in some locations. Should have it ready to order in a couple days.

I'm also going to lock it the feature set for this version too. If I keep adding stuff I'll never get anything built.

-Hans

I feel its wiser to keep the pwm outputs in the board and ph as separate. Its a relatively expensive. standlone module (ph). In its current form that can be used, sourced, assembled or added/removed from an existing build easily (just hook up the i2c wires). The same is not true with PWM, they have much bigger use cases, they are cheaper and you will have lesser complexity on the board. Doing the pwm bits by hand with through hole components is rather tricky i feel.
Your call at the end, its DIY and opensource , so nothing stops you really from tinkering with the design. I do think theres might be some niche use cases with dual ph probe.

 

[hhaase]

All good thoughts. I'm still figuring out how I want to sub-divide everything in the long term to be honest. Particularly with me not having a reef tank again yet (it'll be a month or two till I can set it up).

Right now I don't have anything I can PWM control, so it's a lower priority for me,. But I have a freshwater tank and my RO storage system I can monitor. So I've been focused mostly on the monitoring portion.


-Hans

 

[Des Westcott]

I've always though that modular stackable hats are the way. Start with a Pi. You only want equipment control? Stack an equipment control hat onto the Pi. You want to control lighting? Add a Light control Hat to the top of the stack. You want a few dosers 6 months down the line? Stack a doser hat on top.

Or am I missing something as usual? maybe limit it to 3 hats that when used together will give you full functionality, but you can choose to have partial functionality if you prefer to start and then increase later really easily.

 

[Michael Lane]

I've always though that modular stackable hats are the way. Start with a Pi. You only want equipment control? Stack an equipment control hat onto the Pi. You want to control lighting? Add a Light control Hat to the top of the stack. You want a few dosers 6 months down the line? Stack a doser hat on top.

Or am I missing something as usual? maybe limit it to 3 hats that when used together will give you full functionality, but you can choose to have partial functionality if you prefer to start and then increase later really easily.

The difficulty with stacking hats is ensuring gpio compatibility between the modules. It either requires standards, or a disciplined design and everything from a single designer/vendor.
It's an interesting idea though. I've considered making a pi tower based on that concept.

 

[hhaase]

My other big issue with stacked hats, or multiple boards of other flavors, is because of the unique aspects of reef electronics. It's fairly common, due to convenience, to see various reef electronics mounted inside a cabinet that also has an open sump. This is a perfect atmosphere for oxidation, corrosion, and dendritic growth (tin whiskers). Every piece of electronics on my old tank suffered from this to one degree or another.

There are a lot of ways to environmentally seal electronics on a circuit board, either via conformal coatings, or urethane potting, if the boards are designed to make this possible. However, it's really hard to affordably make connectors protected from a salt environment. So the less connectors you have, the better.

 

[Des Westcott]

Dewd's Big Cube Reef-Pi build

RTC installed Nice is the RTC working like its supposed to

www.reef2reef.com

Yeah. Electronics and the sumo environment don’t mix. Have a look at my build thread above. I’ve separated the electronics from the sump environment entirely to avoid that exact issue.

 

[Ranjib]

The difficulty with stacking hats is ensuring gpio compatibility between the modules. It either requires standards, or a disciplined design and everything from a single designer/vendor.
It's an interesting idea though. I've considered making a pi tower based on that concept.

Yes.. I too do not like HAT as a general-purpose solution. Its not impossible to really make an all-inclusive design, but I think its pretty hard, the form factor itself imposes a challenge.
First of all, lets call out a key thing, an official Pi HAT is a very specific thing, it has to conform to certain guidelines, including a specific EEPROM spec for auto-detection. Only then it can be called as HAT. Otherwise, we should just call it Addon board, with HAT's form factor (i.e. it sits on top).

The problem I see with stacking HATs are
1) The form factor becomes weird. You get a brick-shaped thing where pi connectors (HDMI, sd card slot etc ) are in one place.. now for exposing all PWM, outlet, inlet, ph probe you'll need connectors in another place. So if you conceptualize the end product, you have a brick-like thing with connectors popping up from multiple directions:-/ . I dont like that. I prefer the traditional rectangular shape with connectors spanning in one side only, this eases mounting and we know how to do brackets etc.. Its not impossible to get other designs, but they required significant design thinking/work.
2) The power delivery can get complicated, this typical perf board or pcb boards are less than 3A rated. The power requirements are kinda blocker for arbitrary stacking.

 

[Des Westcott]

The difficulty with stacking hats is ensuring gpio compatibility between the modules. It either requires standards, or a disciplined design and everything from a single designer/vendor.
It's an interesting idea though. I've considered making a pi tower based on that concept.

That's kind of how I envisaged it. One supplier / designer made 3 or 4 modules that worked together, but weren't necessarily compatible with others. Although it would be fantastic IF that could be the case. I would definitely support that one guy. Maybe not all at once, but once I bought into his system, I would definitely go back to him to add to the system.

Kind of like a reward for taking the time to design and produce a full package deal.

 

[Des Westcott]

Yes.. I too do not like HAT as a general-purpose solution. Its not impossible to really make an all-inclusive design, but I think its pretty hard, the form factor itself imposes a challenge.
First of all, lets call out a key thing, an official Pi HAT is a very specific thing, it has to conform to certain guidelines, including a specific EEPROM spec for auto-detection. Only then it can be called as HAT. Otherwise, we should just call it Addon board, with HAT's form factor (i.e. it sits on top).

The problem I see with stacking HATs are
1) The form factor becomes weird. You get a brick-shaped thing where pi connectors (HDMI, sd card slot etc ) are in one place.. now for exposing all PWM, outlet, inlet, ph probe you'll need connectors in another place. So if you conceptualize the end product, you have a brick-like thing with connectors popping up from multiple directions:-/ . I dont like that. I prefer the traditional rectangular shape with connectors spanning in one side only, this eases mounting and we know how to do brackets etc.. Its not impossible to get other designs, but they required significant design thinking/work.
2) The power delivery can get complicated, this typical perf board or pcb boards are less than 3A rated. The power requirements are kinda blocker for arbitrary stacking.

OK. Maybe I've been too free with using the term "HAT". I probably mean "Add-on Board"

I'm actually thinking that with a bit of planning, this "unified approach" could actually work out better with regard to form factor. Imagine having an enclosure ready-made for the Add-on Boards (or design available as printable on Thingiverse) . Each board already has the mini stereo / DB9 / XLR receptacles attached and mounted to a panel that slots into the case. So just by adding one board to a pi in the correct case, you need no wires between components and all your sockets are right there on the outside of the case. You just plug the sensors / powerstrips / whatever straight in.

I don't know. I'm just throwing ideas out here without a proper insight into what's required to accomplish what I'm talking about / imagining. Adding a laymans perspective to try avoid the challenges around wiring, soldering and case design / building that may be a barrier to more people getting into Reef-Pi.

I show mates pictures of my Reef-Pi setup and most of them just say "no f*&%$#g way" can they even imagine what's going on there.

 

[Ranjib]

OK. Maybe I've been too free with using the term "HAT". I probably mean "Add-on Board"

I'm actually thinking that with a bit of planning, this "unified approach" could actually work out better with regard to form factor. Imagine having an enclosure ready-made for the Add-on Boards (or design available as printable on Thingiverse) . Each board already has the mini stereo / DB9 / XLR receptacles attached and mounted to a panel that slots into the case. So just by adding one board to a pi in the correct case, you need no wires between components and all your sockets are right there on the outside of the case. You just plug the sensors / powerstrips / whatever straight in.

I don't know. I'm just throwing ideas out here without a proper insight into what's required to accomplish what I'm talking about / imagining. Adding a laymans perspective to try avoid the challenges around wiring, soldering and case design / building that may be a barrier to more people getting into Reef-Pi.

I show mates pictures of my Reef-Pi setup and most of them just say "no f*&%$#g way" can they even imagine what's going on there.

Yes, I also think this will be awesome. To have streamlined build process where connectors are pre-soldered along with all electronics/circuit. Pico boatd exactly attempted at that. @Roberto_b was also planning to work on something along the same line. Its just the Pi HAT/Addon board form factor that I think makes the connector bits awkard at the end. Pico board's form factor i like much better, we get to line up all the connectors in one broad side. It will be really nice if the Pi ports (hdmi, audio, sd card, micro usb etc) are accessible as well. I try to do the with all the 3d printed enclosures. Because I use the perma proto board, i was able to experiment with the HAT style form factor, but all the endproduct was more like cube or brick. I prefer the jewelery box style (set top box, pre-amp enclosures, pretty much most common consumer grade, industrial electronics enclosures) form factor. Primary due to all connectors lining up in one side (sensors, power, pwm outputs etc).

I am not saying its not possible . I was not able to come up with something like that, and I have not seen that problem being addressed yet. I would prefer not to have things attached multiple side of the boards. In some of my builds I have them one above another on the same face, but it think even that is little weird. Though its common in many AV equipment.

Keep your thoughts coming, this is a very interesting topic it helps us to evolve and address feedbacks from enclosure design.
I always think of Apple and dyson devices when comes to topics like this, how they are very different. Both of them build form factors that are exactly opposite to whatever I have mentioned above. Contrary to popular best practices in terms of design & UX. Very inspirational companies. Mac Pro had a very unconventional design. I dont know if anyone have seen one of the SGI O2, desktop computing system. Their CPU unit design was straight from outer space, alient tech

 

[Bigtrout]

Interesting thoughts!
Sorry I dont have time to chime in here, on a work trip in Japan!

 

[hhaase]

I'm not against a modular approach at all, in fact if it's done right it could work out great for guys like me trying to make PCB's available. It worked wonders for the 3D printer market, where essentially all the 3D printers at the hobby/home level are based around a couple basic standards of board layouts, physical layouts, and software sets.

Generally form follows function. A great starting point would be to define which features would go on which module, and once that's defined we should standardize connector and signal types between the modules. This way we're not all re-inventing the connectivity standards from iteration to iteration, and modules from different sources would be easily interchangeable. I'd put a high preference for connectors that have waterproof styles available, with non-corroding housings.

But the first thing I think we should agree on is which side of the Pi board the header should go

 

[Zippyfear]

The difficulty with stacking hats is ensuring gpio compatibility between the modules. It either requires standards, or a disciplined design and everything from a single designer/vendor.
It's an interesting idea though. I've considered making a pi tower based on that concept.

Shout out to Michael Lane, the rebuild with the HAT (or add-on) as it may be called - going great! Equipment control and temp probes are functional, Next up - ATO and PH probe.. Eventually lighting control.. one step at a time!

 

[Ranjib]

Shout out to Michael Lane, the rebuild with the HAT (or add-on) as it may be called - going great! Equipment control and temp probes are functional, Next up - ATO and PH probe.. Eventually lighting control.. one step at a time!

Looking good . Curious why some connectors are mounted on the backpanel ?

 

[Soulreefer]

Just share my build...

Original pcb before cut

After cut
With 2 pcb.

Next..Add fan on top raspberry
stick to the clear acrylic, I hope this week can be finished all.

Thanks

 

[Ranjib]

Just share my build...

Original pcb before cut

After cut
With 2 pcb.

Next..Add fan on top raspberry
stick to the clear acrylic, I hope this week can be finished all.

Thanks

This looks super duper cool. How can I get one of these ?