2009-08-25 10:13:14     /dev/video0

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2009-08-25 10:13:14     /dev/video0

Steven Sheppard (UNITED STATES)

Message: 79194   


I'm trying to get the OV9655 camera (Surveyor Camera) to work with my Bluetechnix CM-BF537E Board.  I followed all of the instructions on this page:






But I can't get /dev/video0 to show up.






root:/> modprobe i2c-bfin-twi


i2c-bfin-twi i2c-bfin-twi.0: Blackfin BF5xx on-chip I2C TWI Contoller Driver, Ve


rsion 1.8, regs_base@ffc01400


root:/> modprobe blackfin-cam


Linux video capture interface: v2.00


OV9655: detecting client on address 0x60


OV9655: V4L driver Blackfin CMOS Camera now ready


OV9655: i2c driver ready


root:/> cd dev/


root:/dev> ls


console    gpio18     gpio29     gpio4      gpio8      ram10      ram8


full       gpio19     gpio3      gpio40     gpio9      ram11      ram9


gpio0      gpio2      gpio30     gpio41     kmem       ram12      random


gpio1      gpio20     gpio31     gpio42     kmsg       ram13      root


gpio10     gpio21     gpio32     gpio43     mem        ram14      sport0


gpio11     gpio22     gpio33     gpio44     mtd0       ram15      sport1


gpio12     gpio23     gpio34     gpio45     mtd0ro     ram2       tty


gpio13     gpio24     gpio35     gpio46     mtdblock0  ram3       ttyBF0


gpio14     gpio25     gpio36     gpio47     null       ram4       ttyBF1


gpio15     gpio26     gpio37     gpio5      pts        ram5       urandom


gpio16     gpio27     gpio38     gpio6      ram0       ram6       zero


gpio17     gpio28     gpio39     gpio7      ram1       ram7








Any help or advice would be greatly appreciated.  As I've posted before: I'm very new to this, so please talk down to me.




2009-08-25 10:16:29     Re: /dev/video0

Steven Sheppard (UNITED STATES)

Message: 79196   


BTW, I'm using dist 2008R1.5-RC3




2009-08-25 10:21:45     Re: /dev/video0

Steven Sheppard (UNITED STATES)

Message: 79197   


OK.  I got the video0 to appear using the command:


mknod /dev/video0 c 81 0


I found that on a forum post, and I'm not sure what the "c 81 0" stand for.  However, I don't seem to be able to open it.






root:/dev> v4l_test

usage: video_cap [-r <frame_rate>] [-o <output file>]using default setting: coul

dn't allocate bottom buffer - kernel start address too low


capture rate: 30, height: 288, widht: 352

open /dev/video0

cannot open /dev/video0





2009-08-25 10:26:10     Re: /dev/video0

Mike Frysinger (UNITED STATES)

Message: 79199   


please search the forums.  people have already debugged this camera module and found the I2C vs SCCB to be problematic.




2009-08-25 10:56:05     Re: /dev/video0

Steven Sheppard (UNITED STATES)

Message: 79202   


I read throught some of that, and this doesn't seem to be the problem. When I run the camera driver it seems to work perfectly.  In fact, on the SVR1 board, I could just run v4l_test and it went and captured.  After my last try I went and set the kernel start address to 0x400000, which is the SVR1 default.  The V4L setup page said to use 0x100000.




Now the /dev/video0 opens, but I'm getting an error.






root:/dev> v4l_test

usage: video_cap [-r <frame_rate>] [-o <output file>]using default setting

capture rate: 30, height: 288, widht: 352

open /dev/video0

found Blackfin CMOS Camera device. (maxsize=1280x1024)

default picture properties: brightness=27714,hue=25441,colour=26219,contrast=282

65,depth=16, palette=9.

could not set picture properties: Invalid argument

unsupported video pixel format.





2009-08-25 11:21:16     Re: /dev/video0

Michael Hennerich (GERMANY)

Message: 79205    We added this driver from a patch someone submitted - it was never

tested by us.

In case the sensor delivers data after Power On Reset -

Then the driver would only work in its native resolution 1280x1024 with