2.8" Capacitive Touch Display for Cerb40-II

I have a project that works great using a Teensy 3.1 (Arduino) and an Adafruit 2.8" TFT Cap Touch display.

However, I have some ideas for significantly reducing the cost of it and simplifying installation. So, while I’m at it I’d like to go ahead and convert the project to NETMF. Does anyone have a 2.8" cap touch display that they recommend for use with a Cerb40-II? The Adafruit one has some nice features like an onboard controller and RAM buffering but I’ve seen some impressive work done by the group using Cerbs and the N18. I’m hoping all that won’t be necessary and I can find a cheaper solution just painting directly to the display with the Cerb40-II. I’m not normally one to include a display in my projects. So, feel free to tell me if I’m crazy and should just use the Adafruit SPI display.

use Adafruit…

Or not. :slight_smile:

I have just got a 2.8" TFT going on an Oxygen, using a panel that was ~$9US using that chip (and this library GitHub - veccsolutions/Vecc.Netduino.Drivers.Ili9341: Display driver for the .NET Micro Framework to drive the ILI9341 LCD screens. after the changes I had pulled in - but also watch portrait mode… ). I yet to spend any time on touch but I doubt it’s capacitive… but for $9 will I care?

Edit: it was $8.99US and $0.99US postage. So not as cheap as I said :slight_smile:

Edit2: and maybe if I gave you more info it’d help :slight_smile: http://www.ebay.com.au/itm/121561651848
(I had a lot of trouble finding these displays on ebay, and IIRC I had to search for “Bon.display” the seller, and then look at their items for sale… if you can’t see it from my link, try the same)

@ Brett - Thanks for the tip on the ILI9341. There are definitely some nice prices there. It looks like quite a few pins used on the connector. How many did you end up having to use?

You’re stretching my memory a little, it’s been at least 24 hours since I did that ! :wink: You need reset and data/command pins, you optionally need a backlight enable pin (or turn it always on by pulling high), a ChipSelect pin, and then the MOSI/SCK SPI pins (I don’t think you need MISO, but I have it connected).

Remember I am yet to play with touch :slight_smile:

That’s actually a 2.4" display (61mm measured diagonally) not a 2.8" display, despite the ebay description. The 2.8" is the PCB size.

Just FYI. I find a lot of products from shenzen have sneaky descriptions like that. It doesnt stop me from being addicted to aliexpress and dx though. lol.

My son and I have been playing with a couple of these:

They were $1.50 each when I ordered 2 of them. And for that you get a solar panel, a small motor, 4 wheels mounting screws and the “frame” piece. And they really work (in full direct sunlight) and we race them across our deck, lol.

Ok. So, I talk directly to it with just SPI and I don’t need all 39 pins :slight_smile: Looking forward to seeing more of your results. Have you tested refresh rate yet?

@ mtylerjr, ok, interesting, will take a ruler to it. Grr if so. It is the biggest (clearly) screen I have though.

@ Ian yes, it’s an SPI device so it has the much-reduced connection requirements !

I haven’t played much - literally only got the first bits working (after I made my first pull request in an open source project :dance: ) yesterday. There’s an issue as I logged in Github about the text reversed when using it in portrait mode, which means I am not overly confident in the depth of “other eyes” that have been put to the code. And I don’t expect high framerates out of this either - although I haven’t looked to confirm the @ Taylorza improvement that he gave for Cerb+N18 will be a simple assist. How complex was your screen ?

[quote=“Brett”]How complex was your screen ?

Not super complex. The only thing that requires regular updating is a graph showing temperature.

At a NashMicro hackathon a couple weeks ago, a few of us decided we would build reflow ovens. This one looked nice so we went with it. After getting it open and seeing what was already there and what we were replacing it with I’ve come to the conclusion that a large part of what was there could have stayed and all we really needed to replace was the display and controller and the end result would have been an oven that’s just as good but also much safer. The replacement board from the maker strips out all the safety components and replaces the relay and power supply with much more expensive alternatives for no good reason than I think he just didn’t consider using any of the existing components :frowning:


All that being said, the end result works very well and I would recommend it highly. I just think it can be done a lot better.

screen is ~72mm diagonal. That in my books is a real 2.8" screen.

It’s not fast (the code). I just hooked it up with a few variables written out to it in 6 lines of text, and you can see the paint occur - it’s very linear in it’s action, but plenty of scope to be improved if needed (for me, screen refresh occurs once every 10 secs, hardly a problem :slight_smile: )

@ Brett - Without a Kodak moment it doesn’t exist ::slight_smile:



I see I’m not the only one playing with Gashes Anomalies …

Oh cool! The attached spec on the auction page said the display area was 2.4"

That’s a good price. I may order one too. Thanks for the link!

All of them that I can find in that price range are resistive touch and, unfortunately, none on eBay with cap touch. However, there are plenty on Alibaba in the $10-$15 range. Not bad at all.

What about 3.2" and less wires but … more money too :open_mouth:

yes. please.
Deets please !

When you find a reliable supplier and panel, please do share !

What’s a deet ?

It is resistive touch … and very very very expensive … 80+


sorry - deets = details.

[quote=“PiWi”]It is resistive touch … and very very very expensive … 80+


Ouch! That makes the Adafruit one seem like a bargain. Unfortunately, due to space constraints I can’t go any bigger than a 2.8".