power raspberry pi from usb port?

i've read all sorts of things on the internet. standard usb is 500ma.
some devices will take more than 500ma, and some motherboards will give more than 500ma.

i know apple computers will allow up to 1000ma on usb when a special handshake occurs between the mac and an apple brand accessory like the usb superdrive.

i know hackintosh builds like my own (with an asus mobo) will indiscriminately deliver up to 1000ma via usb

i would like to power the rbp from an mba. it definitely has enough power to boot up, but does anybody have any experience with the power requirements of the EFI flash process and the 500ma supply?

i'd love to hear stories of wins or losses

maybe in a perfect world? perhaps that's why my bus pirate won't initialize.

i exclusively use my iphone6 power brick, which is rated at 1a, and I have countless successful flashes under my belt.

i'd be curious to know what the lowest amperage power supply anybody has used successfully and under what conditions

i've considered the battery route to go completely portable, in which case a screen would be super fun and power wouldn't be a big deal with the right battery.

i'm currently using 6" leads, and VNC from a macbook air for control and hex edit. that's why i'd like to power it from the MBA.

else if

there's a really cool screen for the rbp but it uses some of the SPI pins needed for flashing. is it possible to reprogram/repurpose the GPIO header? the rbp screen that uses the display connector is friggin huge and shits all over my tiny portable plans

FWIW: i'm using rbp2 model b

using rbp2 model b. looking at www.adafruit.com/product/1601

thaGH05T wrote: there should be multiple pins for SPI alternates. Post what model pi you have and what screen you wanna use and I will look into it.

that's what my understanding was, but you were all instilling hope and such

there's a great rbp touchscreen which uses the display port exclusively, but it's freaking huge.

yeh

That's exactly what I'm running into. Maybe I'll just tape two pis back to back, and vnc the one with the display into the other one... LOL