BeagleBone Setup for BB-View
The BeagleBone Black (BBB) is a small single board computer, part of a series of open hardware OMAP boards by TI under the BeagleBoard name and based on the TI AM3358BZCZ100 Sitara ARM8 processor. The latest version carries 4GB FLASH memory and is capable of running a Debian Linux. The BBB I have was sourced from Element14 who have produced a compatible version of their own. There is a BeagleBoard community involved in the ongoing support and development of these boards.
BeagleBoard uses a piggyback extension system based on two 46 pin dual row headers, that accepts extension boards called capes,
BB-View is a resistive touchscreen for the BeagleBoards, also produced by Element14. It comes in 4.3" and 7" versions.
The BB-View presents a major problem in that it has no native support in Debian Linux. Various sources provide advice in recipe form to rebuild a kernel that includes support for BB-View. Unfortunately, unlike food recipes, the ingredients change over time.
In this document is a summary of resources and techniques for building a kernel that includes BB-View support.
Since the outcome is negative, it is placed first.
BB-View support in Linux is insufficient to enable it to be effectively
used as a touchscreen. The calibration is extremely finicky and
requires many attempts to complete
successfully. After that, the touch effectiveness is very poor, and
again requires many attempts to get a button press to be recognised.
This is most likely a problem with the Linux drivers.
change to the 4D Systems' BeagleBone Black 7.0" LCD Cape resolved all
issues, with rapid calibration and button press responsiveness.
Element14 provides information on the BBB and BB-View cape in the form of user manuals, as well as Debian, Angstrom and TI SDK kernel source code and images patched for the BB-View. These are dated 10 June 2014. Instructions in the BB-View manual for patching Debian for BB-View may still work with these files.
Unpatched images from May 2014 are available from the BeagleBoard.org site for Debian standalone and Debian flasher
for flashing to the on-board eMMC. These also have available (for now)
the Debian Wheezy repositories for accessing the whole range of Debian
applications for installing on the BBB. This latter is going to become more important as time progresses.
Another resource is the January 2014 instructions in the Element14 Community for patching the kernel. These will be needed for patching the kernel images from the BeagleBoard.org site. These instructions also still work.
The BeagleBoard.org site has kernel source that is adapted to the BeagleBoard. This includes work to patch the kernel for BB-View. Apparently kernels later than 3.18.X have lost the cape manager so this is the latest kernel version available for the BBB with cape support.
There are also a number of kernel releases for the BeagleBoard on the RCN-EE site.
Patching Kernel 3.8.13-bone37These are the instructions given in January 2014 that still work with a version of Debian provided in May 2014.
Change to the linux-dev folder and change to the 3.8.13-bone37 release. This is quite early but the resulting kernel works OK:
The zImage seems to be the only file needing overwriting in the BBB /boot/uboot directory. Edit the /boot/uboot/uEnv.txt file as follows:
Because the cape has no EEPROM this is needed to force the HDMI off and the LCD on.
Patching Kernel 3.8.13-bone50
This is an adaptation of the above instructions that draw on a later support for BB-View and are generally applicable to other BB kernel releases.