Adding a display to Rpi - 'display best practice'

My apologies if this is obvious, and the other threads re: displays have not really answered my questions.

My Bpi will be used primarily as a brew controller (with wiring extended to use as ferm control in the future) and the panel my friend and I are fitting out tomorrow is a really nice, large, stainless steel thing. I would like to put a display - preferably touchscreen - in the panel. But this will be in the future… I want to just ‘reserve some space’ for the display.

What do you more knowledgable folk think ‘display best practice’ is?

As I see it, there is no ‘wired’ (and therefore stable) data transfer between Bpi and Rpi therefore you almost might as well use ANOTHER wifi step and use an old iPad as a touch screen display (Elco has mentioned this to someone else in the past for adding a display). OR is there a stability advantage in one of these touchscreen modules for the Rpi? They would certainly panel mount a lot easier! Though the iPad or tablet has the advantage of perhaps multi-tasking a little.

I guess the bottom line and primary question is; what is the most stable way of adding a display (to show the web server GUI - is this the right term?) to the Bpi Rpi setup?

Thanks in advance

Between RPi and BrewPi (photon), there is USB as a wired connection.

Easiest would be to use hdmi and no touch. Or indeed use a tablet. Why do you need a rock stable connection for showing the web interface? It is not used for control. I’d just get a cheap android tablet and a mount. While waiting during a long mash step, you can take it off the mount and have a beer outside, still keeping an eye on your temps.

I’m confused.

I thought the web server displayed the interface that controls the Bpi? But you access the Brewpi’s interface via wifi? Is that right? I thought I understood this stuff, but clearly don’t…

It may sound weird, and is DEFINITELY a case of aesthetics defining function, but my stainless panel is huge… a bit too big… I wanted the screen mounted in the centre for looks as much as anything! Can I display the control interface on a screen, and use to make alterations etc?

Thanks

The web server/Pi does exactly what it says: it serves a website. Any computer/tablet/phone on the network can view that website and send user input back.

To clarify, 2 things run on the pi: a python script to manage profiles and data logging and the web server. The web server is an interface to the python script, which in turn talks with the photon over USB.

I suggest a tablet, because you probably won’t find a cheaper screen with touch than with a cheap android tablet.

hmmm… that info actually makes me want to go hardwired. Ive got plenty of other wireless devices to access the web server with.

I think ill get one of these displays for the Rpi. I can get a 7" for about $100.

Shit… I’m super confused here… I have had my Bpi and Rpi for a while, but havent got the software setup on them yet… Its daunting to be honest.

The interface which provides control to the Bpi… is this accessed over Wifi via the Rpi? Can it be accessed in a hard-wired fashion at all?

Sorry if this is dumb…

Does plugging a network cable in your Pi count as hard wired? It is just a web server.

@Elco I understand I can connect the web server to my network with a network cable. I mean adding a display to the whole system so I can control things.

You can tell me what individual piece is, and that the rpi is a web server until you’re blue in the face, but speak to me like I’m a 5 year old here. I want a stable way to add a screen that doesn’t involve a cheap tablet and a wifi connection. I’m not having any manual over rides of my system so I want to increase hard wired links and decrease wifi links.

You need to work on documentation that anyone can understand or you’re going to spend a lot of time moderating this forum.

Thanks.

Control is achieve through the web interface so any device attached to your home network (wifi or cabled) can access this interface to control the BrewPi.

I assume Raspbian (operating system on Raspberry Pi) has a web browser built in? If so you could plug a monitor into the Raspberry Pi and launch this web browser and access the web interface this way.

You could plug a keyboard and mouse into the Pi, and add a small HDMI monitor. You can run a GUI desktop on the Pi, which you will see on the monitor, and you can interact with it using the keyboard and mouse. The Pi is essentially a tiny PC running Linux. Next, you could start a web browser on the desktop and connect it to the Pi’s own IP address- you will see the familiar BrewPi web interface.

Another option is to plug in a small video monitor, such as those in portable DVD players, or installed in some car dashboards. The resolution of these displays is not so good, but it may be adequate.

Finally, you could buy the official Raspberry Pi touch screen display. It has a good resolution and touch input. You can run the desktop GUI and then the web page and control it by touch.

All of these options will require a little bit of fiddling with mounting, power supply and wiring, but it should be pretty easy.

1 Like

Just the run-down I needed @ame - everything works the way I thought, with the exception of @Elco clarifying early on in this thread that theres the wired link between the pi’s (I missed this somehow). I’m a pretty well educated person, but am easily overwhelmed by the I.T jargon surrounding Bpi, Rpi, web servers, etc… and it got the better of me here.

Ordering the Rpi 7" screen tonight. Hopefully will arrive for testing early next week.

I’ll let everyone know how it works…

Just to check you say you’ve got the Brewpi, so if you have bought the version @elco sells you have all the necessary parts and don’t need a screen really you can control everything from the nobs/touch screen.

If you’ve taken the approach of diying using the arduino and are adding a touch screen in my experience it’s not straight forward it took me hours sourcing the drivers etc, and the. Actually navigating the web ui (see graphs editing temps etc) really wasn’t an enjoyable experience. I’ve posted my set up on this forum somewhere.

You’d be best off with a monitor, keyboard and mouse attached, if you really want to be hard wired.

Just for info though youll most likely control the brewpi through safari windows explorer chrome etc… Whether that’s through a monitor attached to the raspberry pi or via your phone, laptop, desktop etc. So if you have a reliable wifi connection there really is little difference in interacting with the brewpi.

Arguably it’s faster/easier to see a fault sat on your Arse in the lounge checking brewpi on your phone and seeing you can’t get a connection to brewpi than it is walking to your brew fridge waking up your monitor and logging onto the brewpi web ui anyway and seeing you can’t get a connection to brewpi.

(Obviously using an Ethernet connection would deliver the same results too)

Yep I have the brewpi.

It’s good to hear your experience @mikmonken I have digested your post a few times in the past actually. I am hoping that not having a diy arduino system makes it easier?

Bear in mind this is primarily for brew control not ferm. As mentioned at the start of this thread, a lot of this is for aesthetics.

I’m looking at 2 options currently. Both have the ability to easily lengthen the cables so swinging my panel door open is ok. The DSI cable options look annoying in this regard.

I like this: http://www.chalk-elec.com/?page_id=1280#!/14-HDMI-interface-LCD-with-capacitive-touchscreen/p/36248806/category=3094861

And this: http://www.adafruit.com/products/2407

Both will require adding an onscreen keyboard but that’s cool.

Both will panel mount neatly.

Very different size wise, there are lots of 7" options but nothing bigger except these from chalk…

Anyone have an opinion on these?

I would go with the official raspberry pi touch screen. I have no experience with it, but because it is the official screen, it will have the best support and will work out of the box.

You can then just set a web browser to start automatically when the system starts and set the home page to localhost to show the BrewPi web interface. It will be exactly the same as opening the web interface on any other system, you just point the raspberry pi to itself. The Raspberry Pi will not even need a network connection for this to work.

I prefer to use my desktop and phone/tablet, because the touch screen is usually better (capacitive) then the 7" screens you can get for the pi, which are resistive.

I’m also trying to plot my build out on paper currently and have had these same thoughts. Trying to make a clean looking control box that has the necessary screens, ssr, outs/ins, spark, RasPi, etc.

If I buy the diy version of the SparkV2 with the touch screen, is there any need for having a monitor attached to my RasPi? I think it would be neat to see the web UI from my control box but not sure if it would be totally redundant to have two screens.

Does the SparkV2 screen have the ability to display the web UI or is it strictly a resistance touch screen that allows you to turn set points up and down?

Would it be possible to make a control box and just internalize the SparkV2, RasPi and then have one larger mountable HDMI screen that always shows the web UI? Would it be better to make said control box with two screens (the SparkV2 screen and another larger screen that basically just serves as the RasPi monitor showing the web UI)?

Any thoughts on my random questions?

It’s a simple touch screen. It is impossible to show the web UI on the screen.
It is also not possible to control all settings from the touch screen, it will just be used for simple temperature changes.

If you want to display charts locally, you’ll have to add a display to the pi. Or wall mount a tablet and load the web UI over WiFi.

So if we were going to have a screen added to the RaspPi and our enclosure, it would be possible to just remove the Spark screen or just internalize the whole thing and make adjustments from the larger screen and web UI? Is there any reason I wouldn’t want to do that?

Thanks again!

The screen is not required, it is mostly informative. You can do everything via the web ui.

@bryancm1 You are having the same thoughts as me, but articulating them better I think.

I have my panel built and am testing. I must say I like having the brewpi screen. I wouldn’t do away with it. Things like hardware test mode are great!

I definitely think having the brewpi with screen inside the panel and an external raspi touchscreen showing the interface on the front of the panel is a great idea. I like that it will not rely on my wifi (my house is big and I just don’t trust wifi) and that I might be able to avoid buttons LEDs and switches. At this stage I have no manual items and will try to operate like this until I feel I need to add them.

I’m trying to piece it all together with cardboard and paper currently, trying to design a box to utilize the screen attached to the Spark and then another 7" TFT HDMI screen. Do you happen to have the dimensions of the DIY Spark w screen? Hoping I can get all of this and the SSRs in one box!