A system is described that includes a power conversion module, a data port, a controller to receive data from the data port, and a data store containing instructions that when executed by the controller perform operations to control the power conversion module. The operations include executing instructions in a first portion of the data store during booting of the controller, executing instructions in a second portion of the data store after the controller has booted, receiving a signal from the data port indicating the instructions in the second portion are to be modified, receiving from the data port modified instructions to be stored in the second portion, and executing, in response to the signal, the instructions in the first portion to store the modified instructions in the second portion.