This is a very basic setup that sets the USB display as the default X display. If you startx you should now see, and be able to interact with, your Pi desktop on the display.
I’ve tried some alternate configs, which I’ll post more about when I get home and retrieve them off my Pi.
I’ve followed this tutorial, the usp display works great on raspberry pi2… but, it still has some problem with display O tron 3000 which doesn’t output any text on the display.
That’s strange. Do you get any errors with the Display-o-Tron? Have you tried re-installing the drivers and, particularly, the spidev library which I updated for Pi 2 compatibility? Try:
sudo pip install -I dot3k
( changed that line to say dot3k, since that will reinstall dpidev, sn3218 and st7036 )
Oo, I should have mentioned that this is absolutely expected. Changing to the USB display disables HDMI. Although I think you’ll still see something while booting up.
If you rename the 10-robopeak.conf to 10-robopeak.conf.off you should get back to normal.
I’ve got configs that work with both displays in various configurations, but I haven’t had time to write them up yet!
This is odd. Does the joystick work? The display relies on a couple of GPIO pins, so if general GPIO isn’t working then it wont show text. It can also get into a funny state sometimes, so a power-cycle ( total disconnect of power ) can help.
It’s something wrong with my Kernel and RPi.GPIO- they just don’t play nice together. I just ran into this myself, and couldn’t reset my Propeller HAT- spent far too long debugging it before I realized I was running a custom kernel.
Disabled the kernel and… well everything works again. D’oh. I clearly need to go back to the drawing board and find out why this happens.
If you have a config that works for USB and HDMI – say, GUI on USB and console on HDMI, that would be fantastic. I’ve been fiddling with getting this working on the B+ and gave up to just use it with the Pi 2 instead.
hi, I am sorry if my question is very basic. Does this post assume that I already have a raspbian installed on the SD card? And then i do this to setup the display?
Hi, I have setup raspbian wheezy on an SD card and then tried these steps to install the display. When I rebooted the pi nothing happened. Because I know HDMI would disable I was looking for the 2.8" display to show something. But it only stayed black :(.
So what can I do now? Rewrite raspbian on the SD Card and then?
Did you follow the steps to set it as the default X display? Does your Pi “startx” automatically?
If your 2.8" display is staying solid black, after showing the boot up logo, then it should be working. Plug in an HDMI display and follow the final step to test it:
cat /dev/urandom > /dev/fb1
If this works, and you see random rainbow noise on your DFRobot display- then congrats, it’s setup successfully!
To keep everyone’s sanity, I didn’t include steps for disabling HDMI output and switching only to the USB display, since it would be a nightmare to debug such a setup if it didn’t go well.
isn’t the ‘square rainbow’ thingy an indication that something is draining too much power? maybe that is the problem and trying to boot from a more beefy PSU would be required?