[Solved] Waveshare32b V4 LCD black screen on startx

[Sandbird]

I dont understand why i am having such a hard time using my lcd with an old pi1 running the latest noobs, raspbian.....
I've done everything mentioned here: https://github.com/swkim01/waveshare-dtoverlays on how to get this working.
Adding

Code: Select all

fbcon=map:10 fbcon=font:ProFont6x11 logo.nologo

to my cmdline.txt actually allows me to see the boot up text scrolling on the screen, but right when the pi is about to get into startx the screen on the LCD goes black.....no arrow no nothing.

Code: Select all

root@raspberrypi:~# dmesg | grep spi
[   13.112103] spi spi0.1: setting up native-CS1 as GPIO 7
[   13.112382] spi spi0.0: setting up native-CS0 as GPIO 8
[   13.168308] ads7846 spi0.1: touchscreen, irq 411
[   13.169415] input: ADS7846 Touchscreen as /devices/platform/soc/20204000.spi/spi_master/spi0/spi0.1/input/input3
[   13.596167] graphics fb1: fb_ili9340 frame buffer, 320x240, 150 KiB video memory, 4 KiB DMA buffer memory, fps=25, spi0.0 at 16 MHz

I also enabled spi via raspi-config.
What am i doing wrong here?
Thanks

[DirkS]

You need to configure X to use the correct framebuffer.

Move /usr/share/X11/xorg.conf.d/99-fbturbo.conf out of the way:

Code: Select all

sudo mv /usr/share/X11/xorg.conf.d/99-fbturbo.conf \ ~/

Create new configuration file

Code: Select all

sudo nano /etc/X11/xorg.conf.d/99-fbdev.conf

with thr content

Code: Select all

Section "Device"
  Identifier "myfb"
  Driver "fbdev"
  Option "fbdev" "/dev/fb1"
EndSection

For the touch panel create the file /etc/X11/xorg.conf.d/99-calibration.conf

Code: Select all

sudo nano /etc/X11/xorg.conf.d/99-calibration.conf

containing

Code: Select all

Section "InputClass"
        Identifier      "calibration"
        MatchProduct    "ADS7846 Touchscreen"
        Option  "Calibration"   "219 3835 3984 219"
        Option  "SwapAxes"      "1"
EndSection

[Sandbird]

You need to configure X to use the correct framebuffer.

oh crap, i thought this was not necessary anymore (using the new method since i dont have to patch the kernel anymore).
If i am not mistaken i remember leaving 99-fbturbo.conf as it is just change fb0 to fb1 ? Or i should just move it out of the way.
I guess if i ever want to hook up my display again, i have to reverse all the above right?

One final question. I've never figured out how to change resolution to the screen, to make the IDX 'fit' nicely in the display. Is that even an option ? Or because the screen is 320 x 240...thats the best it can do ?

Thanks DirkS for taking the time to answer this.

[DirkS]

If i am not mistaken i remember leaving 99-fbturbo.conf as it is just change fb0 to fb1 ? Or i should just move it out of the way.

The 'driver' entry in the conf file needs to be changed too. Moving it out of the way is easier to use (especially in scripts)

I guess if i ever want to hook up my display again, i have to reverse all the above right?

You don't need to undo all the changes. If you don't care about the console then you could probably get away with just swapping the 99-xxx.conf files.

One final question. I've never figured out how to change resolution to the screen, to make the IDX 'fit' nicely in the display. Is that even an option ? Or because the screen is 320 x 240...thats the best it can do ?

IIRC someone mentioned here on the forum that you could try to change the framebuffer size and it would then rescale, but I have never looked into it (I don't use X on my small screens)

[Sandbird]

Awesome, thanks for the info

[Sandbird]

sudo FRAMEBUFFER=/dev/fb1 startx -- -dpi 60

is the key to change resolution

[DirkS]

sudo FRAMEBUFFER=/dev/fb1 startx -- -dpi 60

is the key to change resolution

That will cause problems at some point.
Running startx as root is not a good idea and should not be necessary.

Maybe you're running out of disk space...

[Sandbird]

sudo FRAMEBUFFER=/dev/fb1 startx -- -dpi 60

is the key to change resolution

That will cause problems at some point.
Running startx as root is not a good idea and should not be necessary.

Maybe you're running out of disk space...

Adafruit had a trick where you add this at your .profile file, but that didnt work for me...so i have to manually execute startx like this.
My df -h:

Code: Select all

root@raspberrypi:~# df -h
df: β/run/user/0/gvfsβ: Transport endpoint is not connected
Filesystem      Size  Used Avail Use% Mounted on
/dev/root       3.9G  3.4G  278M  93% /
devtmpfs        214M     0  214M   0% /dev
tmpfs           218M     0  218M   0% /dev/shm
tmpfs           218M  4.7M  213M   3% /run
tmpfs           5.0M  4.0K  5.0M   1% /run/lock
tmpfs           218M     0  218M   0% /sys/fs/cgroup
/dev/mmcblk0p6   63M   20M   44M  31% /boot
tmpfs            44M     0   44M   0% /run/user/1000
tmpfs            44M     0   44M   0% /run/user/0
/dev/mmcblk0p9  2.0G  885M 1017M  47% /media/pi/root-rbp1
/dev/mmcblk0p8   79M   20M   59M  26% /media/pi/boot-rbp1
/dev/mmcblk0p5   30M  669K   28M   3% /media/pi/SETTINGS
tmpfs            44M     0   44M   0% /run/user/109

These last 3 lines are from my osmc partition:

Code: Select all

/dev/mmcblk0p9  2.0G  885M 1017M  47% /media/pi/root-rbp1
/dev/mmcblk0p8   79M   20M   59M  26% /media/pi/boot-rbp1
/dev/mmcblk0p5   30M  669K   28M   3% /media/pi/SETTINGS

I'll remove some crap that raspbian has, like games etc.
Edit: Removed wolfram, minecraft, scratch, sonic and then autoremove and freed at least 800mb

[DougieLawson]

Code: Select all

/dev/root       3.9G  3.4G  278M  93% /

How big is your SDCard? Is it really a 4GB card? Or is it an 8GB card that hasn't had the filesystem expanded?

[Sandbird]

Code: Select all

/dev/root       3.9G  3.4G  278M  93% /

How big is your SDCard? Is it really a 4GB card? Or is it an 8GB card that hasn't had the filesystem expanded?

Its an 8GB sd running oscm and raspbian. But since yesterday removed some unnecessary programs to make some space.

Code: Select all

Filesystem      Size  Used Avail Use% Mounted on
/dev/root       3.9G  2.4G  1.3G  65% /
devtmpfs        214M     0  214M   0% /dev
tmpfs           218M     0  218M   0% /dev/shm
tmpfs           218M  4.6M  213M   3% /run
tmpfs           5.0M  4.0K  5.0M   1% /run/lock
tmpfs           218M     0  218M   0% /sys/fs/cgroup
/dev/mmcblk0p6   63M   20M   44M  31% /boot
tmpfs            44M     0   44M   0% /run/user/1000
/dev/mmcblk0p9  2.0G  916M  986M  49% /media/pi/root-rbp1
/dev/mmcblk0p8   79M   20M   59M  26% /media/pi/boot-rbp1
/dev/mmcblk0p5   30M  669K   28M   3% /media/pi/SETTINGS
tmpfs            44M     0   44M   0% /run/user/0

[DougieLawson]

Its an 8GB sd running oscm and raspbian. But since yesterday removed some unnecessary programs to make some space.

OK, so you're suffering from the perils of NOOBS. You've lost nearly 1GB just to have that installed then you're restricting the two OSes.

It's always better to have one OS per SDcard by ditching NOOBS.

[Sandbird]

Its an 8GB sd running oscm and raspbian. But since yesterday removed some unnecessary programs to make some space.

OK, so you're suffering from the perils of NOOBS. You've lost nearly 1GB just to have that installed then you're restricting the two OSes.
It's always better to have one OS per SDcard by ditching NOOBS.

Yes, unfortunately...But its ok...1.3something GB for osmc is fine..its plenty of space.