Firmware Update Procedure for Audio Systems based on CS4953xx DSP family

Firmware plays crucial role in all DSP-based devices. Since firmware defines end functionality and capabilities of these devices it also provides changeability and expandability of devices functions. In DSP systems, firmware update is controlled and performed by MCU and consists of two different parts: downloading of new firmware versions either from Internet or some memory devices into MCUs dedicated external memory and performing the update procedure of the DSP firmware image placed in some other non-volatile memory. This paper describes the latter mentioned part, where MCU has already prepared new firmware version and is executing update program over communication with DSP. Cirrus Logic CS495314 DSP (from CS4953xx chip family) which has been used for years in many commercial audio-video devices was used for testing of this update algorithm. It was provided with CDB49x evaluation board which is used as a typical representative of physical architectures of consumer devices based on CS495314.