Operating system image installation methods

XO-1 signed method	requires .img and fs.zip files	hold down the four game pad buttons
XO-1 unsigned method	requires .img and .crc files	obtain developer key, disable-security, interrupt boot, then use the copy-nand command
XO-1 partitioned method	requires .dat and .img files	obtain developer key, disable-security, interrupt boot, then use the update-nand command
XO-1.5 signed method	requires .zd and fs.zip files	hold down the four game pad buttons
XO-1.5 unsigned method	requires .zd file alone	check if security is disabled, if so obtain developer key and disable-security, interrupt boot, then use the fs-update command

Note that signed methods are the same for XO-1 and XO-1.5. Intentional design, since we do not wish to increase the training burden for the deployment teams.