Computer system with printed circuit boards for extension slots

摘要

A personal computer system has a main circuit board with a central unit (1) and extension slots (29 - 34), each of which can take one printed circuit board (50). The main circuit board has a memory (2), a 32-bit address bus (10) and an input-output circuit (7). Each slot is connected to the 32-bit address bus (10), which is in the form of a NuBus bus, and has special means of identification control, which provide the slot with an identification number (S9) in the computer system. The computer system reserves 256 megabytes of memory space, from position SX0000000 to position SXFFFFFFF, as memory on a card with special number SX in a slot. The card contains decoders, which are connected to the slot to receive the identification number, and have the effect of reserving 256 megabytes of memory space for the card in the slot. <IMAGE>