Firmware updates are performed in a digital device that includes a secure flash that secures each block of stored data with a digital signature. The mounting system is especially suited for applications where the seat back has a hollow portion to contain the control system. The apparatus has an acoustic transducer assembly that emits and receives acoustic signals and an acoustic coupler that acoustically couples the acoustic transducer assembly to the object. Each program consists of instructions belonging to a small instruction set, such as a set consisting of set and clear instructions and wait, release, and stop instructions. A programmable logic device may be used to both multiplex the trace information signals and produce the clock signals necessary to enable their transmission. The acquired images 77 form a panoramic mosaic 85, at least a portion of which is selectively displayed by a display assembly 45 within the vehicle 60.