Method and apparatus are disclosed that allow boot code within the apparatus to be updated using a system controller. The apparatus includes a central processing unit (CPU) and a programmable memory that contains boot code at a predetermined location for use in booting the CPU. The apparatus further includes a bus and a bus master for the bus. The CPU accesses the boot code via the bus and the bus master. The apparatus further includes a system controller. This is operable to write boot code into the programmable memory over the bus. In one embodiment, the above components form a single subsystem within an array of such subsystems. A single control point for the array can transmit updated boot code to the system controller for loading into the programmable memory. This then provides a single interface for simultaneously updating the boot code in all subsystems.