Flexible Logic Unit With One-Cycle Real-Time Task Switching

The invention segments the FPGA resource usage by implementing time-multiplexed task execution. Instead of allocating separate FPGA resources for each task (spatial segmentation), the system divides execution into time slots where a single FPGA instance sequentially executes multiple tasks. This is achieved through context switching mechanisms that load different task configurations into the same FPGA fabric at different times, reducing the required FPGA size while maintaining multi-task capability.

The invention introduces dynamic reconfiguration capability to the FPGA system. The FPGA can dynamically switch between different task configurations through context switching, allowing the same hardware resources to adapt to different computational requirements over time. This dynamic behavior enables a single FPGA to replace multiple static FPGAs, reducing overall resource consumption while maintaining versatility.

The invention implements preliminary action by pre-loading task configuration data into buffer memory before it is needed for execution. When a task switch is required, the configuration data is already prepared and staged in fast memory, allowing the FPGA to be reconfigured without lengthy external memory access delays. This pre-positioning of configuration data significantly reduces context switching time while maintaining task flexibility.

The invention introduces an intermediary buffer memory structure that sits between the external memory and the FPGA configuration input. This buffer memory acts as a mediator that holds pre-fetched configuration data, decoupling the slow external memory access from the fast FPGA reconfiguration process. The buffer memory absorbs the timing mismatch, allowing the FPGA to be reconfigured quickly while configuration data is gradually loaded from external memory in the background.

The invention maintains continuity of useful action by implementing overlapping configuration loading and task execution. While one task is executing, the configuration for the next task is being loaded into buffer memory in parallel. This eliminates idle time during context switching, as the FPGA can immediately switch to the pre-loaded configuration without waiting for data transfer. The useful action of configuration loading continues alongside task execution, minimizing overall switching delay.

The system performs preliminary configuration loading into fast buffer memory before the actual task switch occurs. This advance preparation ensures that when context switching is triggered, the new configuration data is already in place and ready for immediate FPGA loading, minimizing the interruption to real-time operation. The preliminary action of pre-positioning configuration data eliminates the bottleneck that would otherwise extend switching delay.

The invention implements a nested memory architecture where a small fast buffer memory is nested within the FPGA, and a larger external memory is nested outside. The buffer memory serves as an intermediate storage layer that the FPGA can access quickly for configuration and data operations. This nested structure allows the system to leverage both the speed of internal buffer memory and the capacity of external memory, reducing the need for complex external memory interface logic while maintaining data storage capability.

The buffer memory acts as an intermediary between the FPGA and external memory, simplifying the interface requirements. Instead of the FPGA directly managing complex external memory operations for every configuration and data access, the buffer memory handles these operations, reducing the complexity of memory control logic within the FPGA. The intermediary buffer absorbs timing and protocol mismatches, making the overall system easier to design and more fault-tolerant.