Dear community,
We are facing a problem.
We prepared the software development environment using the freescale BSP.
We made the Linux image with default settings.
We displayed the test image ,and
repeat the LVDS output switching(ON/OFF),then
a noise occurs horizontally on the LCD display.
Why will such a phenomenon occur on i.MX6 ?
The procedure to let a phenomenon reappear with a Sabre board are as follows.
[Reproduction Sequence]
Step1 : Change the U-boot environment
Step2 : pour test2.rgb into fb0 in succession
Step3 : ON/OFF repeats the fb0 output switch by “blank command”
Then, a noise occurs horizontally on the LCD display.
The phenomenon occurs with porbability of 1/10 .
[System Configurations]
BSP : L3.0.35_4.1.0
Board : MCIMX6DL-SDP
It seems that the board revision is related.
SCH-27417 REV C4 <-- The phenomenon occurs.
SCH-27417 Rec C2 <-- The phenomenon does not occur.
[Step1] Change the U-boot environment
setenv loadaddr 0x10800000
setenv bootargs_base 'setenv bootargs console=ttymxc0,115200'
setenv bootargs_mmc 'setenv bootargs ${bootargs} root=/dev/mmcblk1p1 rootwait rw video=mxcfb0:dev=ldb,LDB-XGA,if=RGB666,ldb=dul1'
setenv bootcmd_mmc 'run bootargs_base bootargs_mmc;mmc dev 2;mmc read ${loadaddr} 0x800 0x2000;bootm'
setenv bootcmd 'run bootcmd_mmc'
saveenv
[Step2] pour test2.rgb into fb0 in succession
test2.sh is as follows.
#!/bin/sh
echo "test2.rgb"
while [ "1" ]
do
cat test2.rgb > /dev/fb0
done
Test2.rgb format is
[ FF FF FF FF 00 00 00 FF] …… repeat
I attach the input data file (test2.rgb).
[Step 3] ON/OFF repeats the fb0 output switch by “blank command”
sh test2.sh &
echo 1 > /sys/class/graphics/fb0/blank
echo 0 > /sys/class/graphics/fb0/blank
[Enter]
[Enter]
.......... repeat ............
Best Regards,
Koichi Sakagami
Original Attachment has been moved to: test2.sh
Original Attachment has been moved to: test2.zip
