Systems and methods for booting a host device(s) from a peripheral device(s), via an interface, such as an MMC/SD interface, with power terminals, a data bus with data bus terminals, a clock line with a clock terminal and a command line with command terminal. Power is provided to the power terminals, and the command terminal of the MMC/SD or analogous interface is set during power-up to low. The data bus is monitored for a start bit of data transmission.