It is difficult to deal with the two incompatible factors such as high precision and extensive range at the intelligent instruments cored by SCM. There are different functions between input and output at each partition. For it is so hard to compute the exponential functions at the SCM that the writer would divide the output into several partitions, and a math model about polynomial revise in the different partitions combining polynomial revise theory with minimum two-multiplication simulation method is designed. Based on this, the effective measure of increasing the revised data precision is introduced.