Address range extension for a modular computer

摘要

A system and method for accessing a multiplicity of memory devices connected to a serial bus of defined protocol and which a direct memory device selection range smaller than the number of memory devices. The memory devices are divided among microcontrollers which selectively enable one or more memory devices responsive to higher level addressing signals sent to the microcontrollers. Thereafter, selectively enabled groups of memory devices are accessed by applying the limited addressing range of the serial bus. The invention finds particular use in modularized systems where cost and complexity are significant considerations by extending the normal range of the chip select function to increase the memory device count beyond the standard bus protocol. A preferred embodiment uses EEPROM devices and an I2C protocol bus.