Abstract: A video decoding system includes an embedded microcontroller that provides memory arbitration in addition to processing and control functions. The microcontroller architecture provides a first-in, first-out (FIFO) queue for storing memory access instructions and a processing logic for executing software instructions. The microcontroller processing logic determines which components within the decoding system need access to memory and stores a sequence of memory access instructions into the FIFO queue. Each memory access instruction is associated with one decoder component. When main memory becomes available, a memory access instruction is dequeued from the FIFO and transmitted to the associated decoder component, which is then permitted to access memory. The microcontroller receives indicator signals from the decoder components that indicate when the decoder components have finished accessing memory and, thus, when the memory device is available for subsequent transactions.

Abstract: A memory controller features programmable delay buffers that allow the memory interface signals to be automatically adjusted. By fine tuning the delay values, the memory controller can compensate for impedance characteristics that affect the memory interface timing. The memory controller includes a built-in self test mode, in which it runs a series of memory tests using a plurality of different delay combinations for the delay buffers. After running the built-in self test, the memory controller programs the delay buffers to values which allow the memory transactions to occur without errors, ensuring optimal memory interface timing.