Interface bridge between a system bus and local buses with translation of local addresses for system space access programmable by address space

摘要

Interface bridge (13) between a system bus (ASBUS) and at least one local bus (11, 12), the system space directly addressable through said system bus being greater than the system space directly addressable through the local bus, comprising a plurality of programmable decoders (17, 18, 19) each of which defines a distinct range within the range directly addressable through the local bus, and a range attribute as range of local bus addresses to be translated or to be transferred directly to the system bus and also identifies a local bus address as being included or otherwise within the range, so that depending on whether the local bus address belongs to one of the ranges or not and on the range attribute, the local bus address is transferred to the system bus as a direct address or as an address translated by a translation logic (20, 21) and capable of addressing the entire system space.