search

cdsteinkuehler / beaglebone-universal-io

Device tree overlay and support scripts for using most available hardware I/O on the BeagleBone without editing dts files or rebuilding the kernel
GNU General Public License v2.0
127 stars 54 forks source link

[Question] Does loading the universaln cape turn extra hardware modules on? #22

Closed rvega closed 9 years ago

rvega commented 9 years ago

Hi,

Looking at the overlay dts file, I noticed that some hardware resources (uarts, i2c, spi, pru, etc.) are claimed.

Does this mean that when the cape is loaded, these hardware modules are powered on? I'm worried that doing this will increase power consumption, which is not good for my battery powered application.

If the answer is yes (hardware modules are turned on), would this be prevented by removing fragment@10 to fragment@40 from the dts file?

cdsteinkuehler commented 9 years ago

On 12/11/2014 8:03 AM, Rafael Vega wrote:

Does this mean that when the cape is loaded, these hardware modules are powered on? I'm worried that doing this will increase power consumption, which is not good for my battery powered application.

Yes, the modules will be powered on and will increase power consumption.

If the answer is yes (hardware modules are turned on), would this be prevented by removing fragment@10 to fragment@40 from the dts file?

Yes, removing fragments 10-40 will prevent this, but for minimal power consumption you should probably craft a custom device tree that enables only the hardware you need (ie: don't export any unneeded GPIO pins, disable the LCD/HDMI controller, etc.).

Charles Steinkuehler charles@steinkuehler.net

rvega commented 9 years ago

Thanks! :)