PRU PWM

###Updating kernel

Check your kernel version using uname -r
If you get 3.8.13bone56+ as output then you may skip Updating kernel.
For other kernel versions write following cmds in your BBB:

wget https://rcn-ee.net/deb/wheezy-armhf/v3.8.13-bone57/install-me.sh
chmod +x install-me.sh
./install-me.sh

After above steps reboot and check your kernel version using uname -r,it should be 3.8.13bone57

NOTE: For Ubuntu different scripts shall be used. E.g., for precise: - http://rcn-ee.net/deb/precise-armhf/v3.8.13-bone57/install-me.sh

###Setting Up PRU Compiler You should first check if there is the PRU Compiler available in your Linux-Distribution.

apt-get update
sudo apt-get install ti-pru-cgt-installer

If it is not available in your Linux-Distribution you have to download it from the TI website.

Download PRU C Compiler v2.0.0B2 installer
Please check the path where you install PRU compiler.
Setting environment variable

echo export PATH=/path/to/pru/compiler/bin:$PATH >> ~/.bashrc
echo export PRU_C_DIR="/path/to/pru/compiler/include;/path/to/pru/compiler/lib" >> ~/.bashrc
source ~/.bashrc

note: semicolons in second command were intended

###Compiling and loading the code

just make
copy generated executable pwmpru1 to ardupilot/Tools/Linux_HAL_Essentials/.
To load firmware use
- ./startup.sh load : only once after reboot it will copy overlays and firmware to /lib/firmware/ and loads them.
- ./startup.sh reload : it only copies firmware to /lib/firmware/ and reloads pru firmware.
Enable loading cape during BBB startup (no need to follow above step if you do this step once):
- cp BB-PXF-01-00A0.dtbo /lib/firmware
- add cape_enable=capemgr.enable_partno=BB-PXF-01 to /boot/uboot/uEnv.txt
- add CAPE=BB-PXF-01 to /etc/default/capemgr