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Problem with the framebuffer on an ARM device
ilpaso last edited by
I installed Qt Embedded on a ARM device with linux.
There is a problem with the framebuffer.
Running a simple application (./application -qws) it returns:
@Cannot create semaphore /tmp/qtembedded-0/QtEmbedded-0 'd'
Error 38 Function not implemented
Cannot get display lock
but when I try to run the framebuffer example application it returns
@The framebuffer device was opened successfully.
Fixed screen info: id: imapfb smem_start: 0x44800000 smem_len: 4718592 type: 0 type_aux: 0 visual: 2 xpanstep: 0 ypanstep: 1 ywrapstep: 0 line_length: 2048 mmio_start: 0x20cd0000 mmio_len: 16384 accel: 0 The framebuffer device was mapped to memory successfully. Successfully switched to graphics mode. Variable screen info: xres: 1024 yres: 576 xres_virtual: 1024 yres_virtual: 1152 yoffset: 0 xoffset: 0 bits_per_pixel: 16 grayscale: 0 red: offset: 11, length: 5, msb_right: 0 green: offset: 5, length: 6, msb_right: 0 blue: offset: 0, length: 5, msb_right: 0 transp: offset: 0, length: 0, msb_right: 0 nonstd: 0 activate: 0 height: 0 width: 0 accel_flags: 0x0 pixclock: 46213560 left_margin: 128 right_margin: 15 upper_margin: 21 lower_margin: 5 hsync_len: 104 vsync_len: 4 sync: 0 vmode: 0 Frame Buffer Performance test... Average: 39244 usecs Bandwidth: 114.667 MByte/Sec Max. FPS: 25.482 fps Will draw 3 rectangles on the screen, they should be colored red, green and blue (in that order). Done.@
How can I solve?
I changed the permission to the file /tmp/qtembedded-0/QtEmbedded-0 but it returns a "wrong permissions" error
Thank you in advance for your help. I spent the last 3 days around this problem
ngrosjean last edited by
When you launch the framebuffer example, did you have the three rectangle on the screen?
Have you write permission on your partition including the /tmp directory? Perhaps this partition is read-only? What the result of "mount" command?
ilpaso last edited by
Thank you very much ngrosjean for you replay.
I'm very disperate!
When I launch the framebuffer example there are the three rectangles on the screen in the right order and the output is written in my previous post.
I tried to change the permissions on /tmp directory. /tmp is a link to /var/tmp so I changed the permission on /tmp/var.
When I try to run another example after changed the permission the system returns a "wrong permissions" error.
This evening I'll try the mount command and I'll post a replay.
Thank you again
stas2 last edited by
I have recently had the same problem. Turned out that I had to include System V IPC option in the kernel.