In the protected address mode, the 80286 CPU has an extented memory addressing capability up to 16 megabytes. By calling the appropriate system BIOS functions, the data block transfer in the protected mode can be realized in a 80286 microcomputer easily. Appling this function to the design of a signal processing system based on a 80286 microcomputer as CPU, we can obtain a system which can effectively perform data acquisition with high speed and enormous volume and parallel processing with multiple DSP acceleration boards. The authors，using this method，have designed and realized successfully a DSP system which has excellent performance.