Home › Forums › Forums › Technical Support for PiScreen › [Resolved]PiScreen – No Picture / No Backlight
- This topic has 8 replies, 2 voices, and was last updated 8 years, 10 months ago by bored.
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- November 3, 2014 at 10:16 pm #2865boredParticipant
Hi Folks,
Looking for a bit of support.I put the piscreen together, however, there’s no picture or backlight.
I’ve installed the drivers, following the instructions at https://ozzmaker.com/piscreen-driver-install-instructions-2/
The touchscreen looks like it’s working though (I can see things happening when I cat /dev/input/event0)
Any help would be appreciated.
ls -l /dev/input/event*
crw-rw---T 1 root input 13, 64 Nov 3 21:50 /dev/input/event0
cat /proc/bus/input/devices
I: Bus=0000 Vendor=0000 Product=0000 Version=0000 N: Name="ADS7846 Touchscreen" P: Phys=spi0.1/input0 S: Sysfs=/devices/platform/bcm2708_spi.0/spi_master/spi0/spi0.1/input/input0 U: Uniq= H: Handlers=mouse0 event0 B: PROP=0 B: EV=b B: KEY=400 0 0 0 0 0 0 0 0 0 0 B: ABS=1000003
November 3, 2014 at 10:38 pm #2866Mark WilliamsKeymasterHi
Can you please show us the output ofdmesg
and
cat /etc/modules
BTW: you checked that the backlight switch is in the on position?
Mark --OzzMaker.com --
November 4, 2014 at 7:02 pm #2868boredParticipantHi Mark,
Thanks for the quick reply.
Yes, definitely checked the switch is in the “on” position! ๐
dmesg output is here:
http://pastebin.com/6ZfKB1jb/etc/modules is here:
http://pastebin.com/eYy2CkJqNovember 5, 2014 at 9:46 pm #2885Mark WilliamsKeymasterThat all looks good, everything loaded properly.
The back light should come one even if nothing is being displayed.the
led:22
in the line below (from /etc/modules) will force the drivers to use GPIO22 to control the back light.
fbtft_device debug=3 rotate=90 name=flexfb speed=16000000 gpios=reset:25,dc:24,led:22
When you installed the drivers, was it from a clean image? We just need to work out if anything else is using that GPIO.
BTW: do you have the Kit or the Assembled PiSCreen
Mark --OzzMaker.com --
November 5, 2014 at 11:39 pm #2887boredParticipantHi Mark,
I have the assembled PiScreen.
The drivers were installed to a clean image of 2014-09-09-wheezy-raspbian.I can confirm that manually toggling GPIO22 (pin 15) on and off from a python console does toggle the backlight on and off.
However, the command:
echo 0 | sudo tee /sys/class/backlight/*/bl_power
both produce this error:tee: /sys/class/backlight/*/bl_power: No such file or directory 0
and it’s the same for echo 1 as well.
After turning the backlight on manually, there’s still no image using fbi.
I should probably also mention that I’m doing all of this through an ssh console – there’s no monitor hooked up to the pi.
I will try a copy of your image tomorrow night, and post back.
Cheers,
Bored
November 6, 2014 at 2:08 pm #2893Mark WilliamsKeymasterMmmmm.
I just triedecho 0 | sudo tee /sys/class/backlight/*/bl_power
and it worked fine for me, but I am running an earlier version of Raspbian, but it has been udpated.I will have to test with the latest image file.
Mark --OzzMaker.com --
November 7, 2014 at 9:58 pm #2898boredParticipanthmmm… the image from your website works fine… so not a hardware issue.
Any other ideas?
Cheers
November 9, 2014 at 5:00 pm #2905Mark WilliamsKeymasterI just tried with a vanilla install of 2014-09-09-wheezy-raspbian.
And it worked fine.Here is the history of commands i used;
pi@raspberrypi ~ $ history 1 sudo rpi-update 2 sudo reboot 3 sudo apt-get update 4 sudo apt-get upgrade 5 sudo REPO_URI=https://github.com/notro/rpi-firmware rpi-update 6 sudo reboot 7 sudo nano /etc/modprobe.d/raspi-blacklist.conf 8 sudo nano /etc/modules 9 sudo reboot 10 sudo apt-get install fbi -y 11 wget https://ozzmaker.com/Raspi_Logo.png 12 sudo fbi -noverbose -T 1 -a -d /dev/fb1 Raspi_Logo.png 13 echo 1 | sudo tee /sys/class/backlight/*/bl_power 14 echo 0 | sudo tee /sys/class/backlight/*/bl_power
Mark --OzzMaker.com --
November 15, 2014 at 1:01 pm #2923boredParticipantHi Mark,
Repeating those steps with a new, clean, image it worked fine.
I have absolutely no idea what went wrong on the previous image.Thanks.
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