Things we need for NiChrome.
To test out USB stick creation, you will need a ChromeOS-formatted boot stick with the right partitions. We don't know how to create those yet. One way to get such an image is with the chromeos recovery tool, found here: https://chrome.google.com/webstore/detail/chromebook-recovery-utili/jndclpdbaamdhonoechobihbbiimdgai?hl=en
You can pick any chromebook to get an image from, since the partition layout is the same on all of them, and the usb tool replaces the A image anyway.
To get an image, for both KERN-[AB] and ROOT-[AB],
Build the usb tool: (cd usb && go build .)
Plug in the chromeos-formatted USB stick.
./usb/usb -fetch=true -dev=/dev/your-usb-stick
e.g. ./usb/usb -fetch=true -dev=/dev/sdb
usb will default to /dev/null, which makes it easy to test it. You can also run travis.sh to test.
You can skip the -fetch=true on second or later runs of usb.
This defaults to writing the A image (partitions 2 and 3). To use the B image, invoke usb with -useB=true