I was a bit confused by this at first as well.  The uEnv.txt file in /boot/ 
is not actually used during the boot process as far as I can tell.  Both 
the uEnv.txt file and the uboot image used to start the kernel are located 
on the separate smaller FAT partition on the drive.  So this is the file 
you will have to change to disable the capes.

For a system without an SDCard (so I can't disable BB-BONE-EMMC-2G) I do 
the following:
Normally the BEAGLEBONE media directory auto mounts, but it didn't for this 
test, so I mounted it manually.
Also note that if you are using an SD card, you would use mmcblk0p1 instead.

root@beaglebone:/# mount /dev/mmcblk0p1 /media/BEAGLEBONE

root@beaglebone:/# ls /media/BEAGLEBONE/
App  Docs  Drivers  ID.txt  LICENSE.txt  MLO  README.md  START.htm 
 autorun.inf  u-boot.img  uEnv.txt  uEnv.txt~

root@beaglebone:/# cat /media/BEAGLEBONE/uEnv.txt
optargs=quiet drm.debug=7 
capemgr.disable_partno=BB-BONELT-HDMI,BB-BONELT-HDMIN

root@beaglebone:/# cat /sys/devices/bone_capemgr.*/slots
 0: 54:PF---
 1: 55:PF---
 2: 56:PF---
 3: 57:PF---
 4: ff:P-O-L Bone-LT-eMMC-2G,00A0,Texas Instrument,BB-BONE-EMMC-2G
 5: ff:P-O-- Bone-Black-HDMI,00A0,Texas Instrument,BB-BONELT-HDMI
 6: ff:P-O-- Bone-Black-HDMIN,00A0,Texas Instrument,BB-BONELT-HDMIN

The uEnv.txt on the fat partition can also be edited in Windows when 
plugging the BBB in via USB.

Zach


On Monday, November 25, 2013 6:01:51 AM UTC-6, Yiqing Liang wrote:
>
> Hi,
>
>    I try to  disable HDMI and emmc by editing the file in /boot/uEnv.txt:
>
> optargs=quiet capemgr.disable_partno=BB-BONELT-HDMI,BB-BONE-EMMC-2G
>
>
> Then I reboot , type:
> cat /sys/devices/bone_capemgr.*/slots
>
> See following:
>
> Last login: Sat Jan  1 00:00:22 UTC 2000 on ttyGS0
> root@beaglebone:~# cat /sys/devices/bone_capemgr.*/slots
>  0: 54:P---L BeagleBone RS232 CAPE,00A1,Beagleboardtoys,BB-BONE-SERL-03
>  1: 55:PF---
>  2: 56:PF---
>  3: 57:PF---
>  4: ff:P-O-L Bone-LT-eMMC-2G,00A0,Texas Instrument,BB-BONE-EMMC-2G
>  5: ff:P-O-L Bone-Black-HDMI,00A0,Texas Instrument,BB-BONELT-HDMI
>
> With letter L, it means it is still enable.. It does not work.,,
>
> So what is wrong, how could I do?
>
> I am using latest Angstrom image (2013-06-20)..
>
> Also, according to some post in Forum, no matter what I change the dtbo 
> file in /lib/firmware/  (to disable /enable uart)
> It has no effect when it reboot.. 
> I just could change in run time, not in boot time....
>
> Yiqing
>

-- 
For more options, visit http://beagleboard.org/discuss
--- 
You received this message because you are subscribed to the Google Groups 
"BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
For more options, visit https://groups.google.com/groups/opt_out.

Reply via email to