Design of equal precision cymometer based on FPGA and SCM

According to the principle of equal precision measurement, a cymometer was designed based on FPGA and singlechip microcomputer. This system was mainly composed of the signal amplification shaping circuit,single-chip microcomputer control circuit,FPGA frequency measurement circuit and the signal display circuit. After amplification and rectification, the signal to be measured and the standard signal were input into FPGA. Two signals were counted in FPGA and controlled by single-chip microcomputer. After received the measuring frequency data, single-chip microcomputer calculated and processed it, and the result of measure was shown. The experiments show that, the cymometer has equal measurement accuracy within the whole frequency measuring range, and it has the advantages of high measuring precision and good operation stability.