supercoconut98
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/dev/fb1 Non-Existent!

Tue Jan 19, 2016 12:11 am

I have been working on this for a few days now. I have a Raspberry Pi B+, with Raspbian Jessie, and a generic TFT 3.2 inch touch screen, which I haven`t been able to make work yet.

Now, I have my drivers installed, with fbturbo and whatnot, I also have the TFT screen installed, and my Pi has detected it correctly, as the TFT screen. I`ve restarted, and apt-get updated so many times. I feel like I have looked through everything possible that I could have, and to no avail, /dev/fb1 does not exist as it should...

Appreciate any and all help!!

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AndyD
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Re: /dev/fb1 Non-Existent!

Tue Jan 19, 2016 7:16 am

supercoconut98 wrote:Now, I have my drivers installed, with fbturbo and whatnot, I also have the TFT screen installed, and my Pi has detected it correctly, as the TFT screen.
Do you have a link to the screen you have? When you say "I have my drivers installed ...", which driver do you have installed? Most of these TFT screens use Notro's fbtft driver. If the driver is installed (even if it is for the wrong screen and fails to initialize the screen) the /dev/fb1 device will be created. So it sounds like you probably don't have the driver installed.

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jackokring
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Re: /dev/fb1 Non-Existent!

Tue Jan 19, 2016 11:30 am

is the overlay in the /boot/overlay folder?
have you added the dtoverlay= line in config.txt?
Pi[NFA]=B256R0USB CL4SD8GB Raspbian Stock.
Pi[Work]=A+256 CL4SD8GB Raspbian Stock.
My favourite constant 1.65056745028

supercoconut98
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Re: /dev/fb1 Non-Existent!

Tue Jan 19, 2016 5:08 pm

AndyD wrote:
supercoconut98 wrote:Now, I have my drivers installed, with fbturbo and whatnot, I also have the TFT screen installed, and my Pi has detected it correctly, as the TFT screen.
Do you have a link to the screen you have? When you say "I have my drivers installed ...", which driver do you have installed? Most of these TFT screens use Notro's fbtft driver. If the driver is installed (even if it is for the wrong screen and fails to initialize the screen) the /dev/fb1 device will be created. So it sounds like you probably don't have the driver installed.
http://m.banggood.com/3_2-Inch-TFT-LCD- ... 11516.html

That is my TFT, and I have installed notro's drivers. I did the REPO_URI command to grab it and install it. And yes, i have included the dtoverlay line in config.txt... But there is no overlay folder in /boot

supercoconut98
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Re: /dev/fb1 Non-Existent!

Tue Jan 19, 2016 6:18 pm

I have yet to find fb1. dmesg says the fbtft driver is loaded, but of course, fb1 doesnt show, and the tft screen is white. I have no idea why it wouldnt work honestly. Im not sure why theres no /boot/overlay. I know the generic screen has the same chip as the Waveshare 3.2b

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AndyD
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Re: /dev/fb1 Non-Existent!

Tue Jan 19, 2016 9:16 pm

I am surprised that fbtft is loaded, but there is no /dev/fb1. I haven't seen that before.

Not all screens have device tree overlays. I have three different TFT screens and only one had an overlay. I wrote my own for the other two, but there is no reason that you can't load fbtft using /etc/modules.

supercoconut98
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Re: /dev/fb1 Non-Existent!

Tue Jan 19, 2016 10:03 pm

There must be an issue I just don't see. I have gotten to the point that the kernel does not report any issues on startup, but I have confirmed that I have my TFT in /proc/bus/input/devices, and I have the correct configuration in /usr/share/X11/xorg.conf.d/99-fbturbo.conf, and I also have my parameters set correctly in /etc/modules, as well as in my config.txt. I'll do what I can to post the contents of my files when I'm near the Raspberry Pi. I deeply appreciate the help, and I am curious as to what the /boot/overlay file is supposed to be, I haven't ever seen it, or come across it in any tutorials. Thank you all again for the help. Seeing as only one other person I have found to have this issue exists, it's either an obscure issue, hardware issue (not very likely at all), or me being an idiot with the answer right in front of me (quite likely, but I don't think that's the case this time around ;P). Last time, I spent two days before work trying to get my Ralink WiFi dongle to work, but it was just the most simple thing: I spelled the ssid myquest9915, having not at all seen that the company is qwest.. not quest. Even after numerous attempts to find any spelling error, heh.

supercoconut98
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Re: /dev/fb1 Non-Existent!

Wed Jan 20, 2016 1:26 am

I've got it to work! I don't know how, but it worked when i used the modprobe this time BUT, i cant get it to do modprobe before loading up the system! I have no idea how the Pi will detect my TFT before it runs the kernel modules, and attempts to start LXDE!

supercoconut98
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Re: /dev/fb1 Non-Existent!

Wed Jan 20, 2016 2:20 am

Update: for whatever reason, /etc/modules is not starting my tft on startup for some reason, though it commands it to.

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AndyD
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Re: /dev/fb1 Non-Existent!

Wed Jan 20, 2016 8:07 am

supercoconut98 wrote:Update: for whatever reason, /etc/modules is not starting my tft on startup for some reason, though it commands it to.
Can you post the line(s) you are adding to /etc/modules and let us know if you are using Raspbian (or Raspbian via NOOBS) and if so, are you using Wheezy or Jessie. There was a change to using /etc/modules in Jessie. For example:-

/etc/modules

Code: Select all

fbtft_device
/etc/modprobe.d/fbtft.conf

Code: Select all

options fbtft_device name=waveshare22 rotate=270 gpios=reset:23,dc:25 verbose=0

supercoconut98
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Re: /dev/fb1 Non-Existent!

Thu Jan 21, 2016 5:01 am

supercoconut98 wrote:I have a Raspberry Pi B+, with Raspbian Jessie, and a generic TFT 3.2 inch touch screen.

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AndyD
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Re: /dev/fb1 Non-Existent!

Thu Jan 21, 2016 8:43 am

supercoconut98 wrote:I did the REPO_URI command to grab it and install it....
You don't need to download the driver from github, Notro's fbtft driver is now a part of the Raspbian Distribution.

Me5000
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Re: /dev/fb1 Non-Existent!

Fri Dec 22, 2017 6:31 pm

supercoconut98 wrote:
Wed Jan 20, 2016 1:26 am
I've got it to work! I don't know how, but it worked when i used the modprobe this time BUT, i cant get it to do modprobe before loading up the system! I have no idea how the Pi will detect my TFT before it runs the kernel modules, and attempts to start LXDE!
How did you get it to work? I have had this same problem for many days now.

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