BENTLY 3500/61 I/O模块
BIOS定义每个设备要使用的PC/AT中断线。BIOS向两个级联的8259A PIC芯片中的每一个写入一个8位矢量，该矢量将每个IRQx映射到存储器中相应的中断矢量。ISA设备中断映射VMIVME-7740 BIOS根据标准ISA架构将IRQx线映射到适当的设备。参考第121页图E-2。无法更改此初始化操作；然而，自定义应用程序可以在BIOS完成初始配置周期后重新路由中断配置。PCI设备中断映射基于PCI总线的外部设备包括两个PCI扩展站点、PCI到VMEbus桥和VGA保留连接。默认BIOS将这些外部设备映射到PIIX4E的PCI中断请求（PIRQx）行。该映射如第121页图E-2所示，并在表E-3中定义。无法修改每个设备上存在的设备PCI中断线（INTA到INTD）。
The BIOS defines the PC/AT interrupt line to be used by each device. The BIOS writes to each of the two cascaded 8259A PIC chips an 8-bit vector, which maps each IRQx to its corresponding interrupt vector in memory. ISA Device Interrupt Map The VMIVME-7740 BIOS maps the IRQx lines to the appropriate device per the standard ISA architecture. Reference Figure E-2 on page 121. This initialization operation cannot be changed; however, a custom application could reroute the interrupt configuration after the BIOS has completed the initial configuration cycle.PCI Device Interrupt Map The PCI bus-based external devices include the two PCI expansion sites, the PCI-to-VMEbus bridge, and the VGA reserved connection. The default BIOS maps these external devices to the PCI Interrupt Request (PIRQx) lines of the PIIX4E. This mapping is illustrated in Figure E-2 on page 121 and is defined in Table E-3. The device PCI interrupt lines (INTA through INTD) that are present on each device cannot be modified.
