Intel 80312 I/O Companion Chip - ECEE

Intel ® 80312 I/O Companion ChipPCI-to-PCI Bridge UnitFigure 4-4 shows an example of connecting S_AD lines to IDSEL inputs of PCI devices andprivate PCI devices.Figure 4-4.Secondary IDSEL Example* These S_AD lines can be either PCI or privatedepending on the SISR register. For example, S_AD[21] canbe used as a private PCI device only when SISR bit 5 is set.PCI-to-PCIBridgePrivatePrivateor Public*PublicS_AD[11]S_AD[12]S_AD[13]S_AD[14]S_AD[15]S_AD[16]S_AD[17]S_AD[18]S_AD[19]S_AD[20]S_AD[21]S_AD[22]S_AD[23]S_AD[24]S_AD[25]S_AD[26]S_AD[27]S_AD[28]S_AD[29]S_AD[30]S_AD[31]IDSELIDSELIDSELIDSELPublic/PrivatePCI DevicePublic/PrivateDevicePrivatePCI DevicePrivatePCI Device4-14 Developer’s Manual