Data transfer methods and controller for transferring data in blocks without crossing certain address boundaries

摘要

A data transfer controller transfers data in blocks having a restricted set of permitted sizes. Before transferring each block, the data transfer controller performs a segmented comparison on the current data address, at which the block starts, and a stopping address, at which the entire data transfer will end, and determines the block size from the result of the segmented comparison. In the segmented comparison, the data transfer controller compares a first part of the data address with a first part of the stopping address, then compares a second part of the data address with a second part of the stopping address. The comparison of second parts is made in different ways, depending on the result of the comparison of first parts.