说明：  8位相等比较器，比较8位数是否相等 -- 8-bit Identity Comparator -- uses 1993 std VHDL -- download from www.pld.com.cn & www.fpga.com.cn
(eight other phase comparators, Comparing the same whether the median 8-- 8-bit Identity Comparator-- uses 1993 std VHDL-- download from www.pld.com.cn)