Hi,
I’ve got the “Banana PI BPI-R4 Pro 4E” arriving soon and I thought I’d buy a screen for it.
Thanks,
- Bana
I’m not sure if vendor image supports i2c or spi,my version shoild not as i have not added it yet (controllers imho disabled for r4pro in dts).
I did not realize that the question was about the Pro. I thought dango said in one post that it had to be activated on the R3 or R4 too.
It is a very enthusiastic project … even more after your comment 
Thanks for bringing this up.
We’re already working on a compatible LCD display for the BPI-R4 Pro family. At the moment we’re validating the hardware and software integration, so it’s a bit early to announce specifications or availability.
If there are particular screen sizes or interfaces (SPI, MIPI DSI, HDMI, etc.) that you’d like to see supported, feel free to let us know. Community feedback is always welcome.
We’ll share updates as soon as we have something ready.
That’s really cool!!!
Essentially, I would like a touchscreen interface/screen so that I can do all the following by programming to do certain tasks when that portion of the screen is clicked. So for example:
That’s just a few that I really would like.
Yes, that is possible.
This screen will support touch input, and we plan to reserve the required connection through the BPI-R4 expansion interface. Once the touch screen is working, you can build your own local UI on top of it.
For example, the buttons on the screen can be mapped to scripts for switching DNS, toggling WireGuard, running speedtest from the CLI, generating a QR code, etc.
So we will provide the touchscreen hardware/interface support, and these applications can be developed based on it.
Do you mean the gpio header or additional hardware (connected by another bus) here?
I’d say make the screen as large as possible as long and there is room to fit it to the top of the Banana PI BPI-R4 Pro 8X and 4E cases.
If you are really going to be making something like you have just shown, that looks like it is going to be fitted to the front of the case.
Maybe you can design two screens: One large one for the top of the case and another for the front of the case?
For now, I am thinking about using the GPIO/expansion header on the R4.Do you have any better suggestions
Yes, the current screen is intended for the front of the case. For a larger top-mounted screen, SPI or I2C may not be enough
I did some tests with a small spi display and reached limits of soc spi. Afaik i2c is slower and is not usable with larger displays than the 128x64 oled i currently use on R3. Gpio expanders imho are mostly i2c so also slow especially when aharing the bus with more devices. Maybe there are options with usb (internal connector to avoid cable on the putside of case).
Most interesting is the software part…my oled via i2c uses python and luma lib. This can be done at userspace with only the i2c detected by kernel. The spi display needs a hack in dts to be recognized by tinydrm driver and afair needs the full drm stack which is imho a bit overkill for diplaying some system parameters and simple grafics (which can be drawn or copied from image files). Spi itself is imho a bit tricky as by default you have no device file for access (need spidev subnode in dt) and also had luma not getting working with spi (low level access driver needs to be built for the lib).
Yes, that matches our current thinking.
At the moment, we are mainly looking at SPI display or serial display solutions. These are more suitable for small front-panel screens, mainly for status information and simple control functions.
For larger screens, SPI or serial may not be enough in terms of performance or driver support, so it may not be a good direction.
The USB idea is interesting. Do you have any good suggestions for a USB-based display solution
No,just see the data throughput and possibility to share speed across devices with hub chips already on board. I would not block a pcie lane or such for it. I guess there are screens with usb (which also could handle multiple devices internally - graphics and touch e.g via simulated serial or directly hid). And it could be tested easier using external port if no internal is there yet.
Maybe this is such a bad idea, but I don’t intend to putting in the 5G modem so I have some spare PCIe slots. Maybe the screen could use that?
You have for the key-m and key-e slots only 2 pcie (shared between them)…so if you want 2 nvme and using the mpcie slots (be14 or similar) you have no pcie free.
Also pcie is a really high speed bus (mostly not needed for small resolutions),not sure if there are m.2 cards with hdmi put or similar.
