According to what I have read you can not disable the GPU on the rPI, but you can minimize how much RAM it uses ( down to around 16MB it seems ) I would however wager if you're not using the GPU, its power signature would be minimal.
rPI A seems to use up to around 300mA( but no onboard networking ), while the rPI B can use up to around 700mA. I can vouch that the BBB can run from a computers USB port, so less than 500mA. Running from USB, I have boot from an external USB drive, with ethernet enabled., while loading the CPU at 99% load ( software test I wrote in C ) Minimal to no GPIO running. Aside from this however, I have not checked to see how much power the BBB draws. But I did run the above test for several hours. I meant to stress the board for the sole purpose of determining stability. It did not crash or glitch once. >From all the reading I have done the only real advantage the rPI has over the BBB, is a much stronger GPU. Power usage seems to be reasonably comparable where I'd bet the BBB has the overall advantage ( no hand on proof though ). Also, the rPI has the slight advantage of software maturity . . . But personally I like where the BBB sits software wise right now. I have no love for the rPI personally, but I could see your project working on either. One thing to note however. If you're going to be running solar to charge batteries . . .the BBB has the right peripherals and enough of them to act as a charge controller( with proper isolation and power mosfets of course ) . . . with plenty to spare. Something that is rather trivial to implement in C. On Sat, Apr 12, 2014 at 1:28 PM, Charles Steinkuehler < [email protected]> wrote: > I think the BBB is the better choice as well, but you'll likely want to > measure real-world power consumption. > > Neither board is really designed as a mobile platform, but the Pi is at > heart a set-top box (powered by AC), while the BeagleBone has it's roots > in tablet-like processors and has fine-grained control over powering > up/down different parts of the chip, CPU speed, etc. I'm not sure on > the Pi if you can disable it's probably power-hungry GPU that is > actually in control of the system (the ARM core is actually a secondary > CPU, the black-box GPU runs the show). > > There are also likely some tweaks to be made with the BBB that will > reduce power consumption, specifically putting the HDMI Tx chip in a > power-down state. The on-board eMMC will also probably help with power > consumption, or at least help a bit with reliability (no uSD connector > to cause problems). > > Finally, the BBB is actually engineered to be able to run off battery, > which is very similar to what you want to do, while I don't know if the > Pi has a means to work with multiple power sources. > > Anyway, best of luck, and ask here if you go with the 'Bone and run into > any problems! > > On 4/12/2014 3:05 PM, Philip Polstra wrote: > > BBB is a clear winner. Lower power consumption, more I/O, easier to do > > CAN, more reliable, more software options. > > On Apr 12, 2014 2:05 PM, "Mübin Icyer" <[email protected]> wrote: > > > >> Hi, > >> > >> We are a gruop of students who want to make a kiosk system with embedded > >> linux boards. We are now in selection phase but we could not decide > which > >> one fits to our requirements. Could you please help us? > >> > >> Our requirements: > >> > >> - Minimum power consumption, since the kiosk will be powered with > >> solar power and battery. > >> - CAN interface is a must, Rasperry Pi doesn't have such an interface > >> but it can be easily makeable at cost of power consumption (a > seperate > >> converter for CAN to uart or i2c will be needed.) > >> - No need for graphical outputs such as HDMI, Video out or so. The > >> connection to the board will be over SSH. > >> - The grapics and text will be displayed on an monochrome LCD or > >> e-paper to reduce the power consumption. > >> > >> Thanks for helps. > >> > >> -- > >> 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/d/optout. > >> > > > > > -- > Charles Steinkuehler > [email protected] > > -- > 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/d/optout. > -- 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/d/optout.
