IS200IVFBG1A系统模块卡件
（续）IRQ AT FUNCTION COMMENTS 44 2 VMIVME-7750产品手册14 20 BIOS Comm I/O与实模式相同15 21 BIOS盒式磁带I/O与实方式相同16 22 BIOS键盘I/O与实模相同17 23 BIOS打印机I/O与实型相同18 24 ROM BASIC入口点与实模19 25引导加载器与实模1A相同26一天中的时间与实模1B相同27控制/中断处理器与实模式1C 28定时器控制与实模式1D相同29视频参数表Pntr与实模式1E相同30软盘参数表Pntr与实模式1F相同31视频图形表Pntr同实模式20 32 DOS终止程序同实模式21 33 DOS功能入口点同实模式22 34 DOS终止处理器同实模式23 35 DOS控制/中断处理器同实模24 36 DOS严重错误处理程序与实模式相同25 37 DOS绝对磁盘读取与实模式26 38 DOS绝对磁盘写入与实模式27 39 DOS程序终止，驻留与实模式28 40 DOS键盘空闲循环与实模式29 41 DOS CON Dev相同。原始输出与实模式2A相同42 DOS 3.x+网络通信与实模式2B相同43 DOS内部使用与实模式2C相同44 DOS内部使用同实模式2D相同45 DOS内部使用相同实模式2E 46 DOS内部使用和实模式2F相同47 DOS打印假脱机驱动程序与实模式30-60 48-96由DOS保留与实模式61-66 97-102用户可用与实模式表2-4 PC中断向量表（续）中断编号IRQ LINE REAL MODE PROTECTED MODE HEX DEC 45中断2 PCI中断外围组件互连（PCI）本地总线上的中断是可选的，定义为“电平敏感”，使用开漏极输出驱动器断言为低（负真）。中断线INTx#的断言和取消断言与CLK异步。当请求设备驱动程序注意时，设备断言其INTx#行。一旦INTx#信号被断言，它将保持断言，直到设备驱动程序清除未决请求。当请求被清除时，设备取消断言其INTx#信号。PCI为单个功能设备定义了一条中断线，为多功能设备或连接器定义了最多四条中断线。对于单功能设备，只能使用INTA#，而其他三条中断线没有意义。第47页图2-1描述了与VME操作和PMC站点相关的VMIVME-7750中断逻辑。多功能设备上的任何功能都可以连接到任何INTx#线。中断引脚寄存器定义函数用于请求中断的INTx#行。如果设备实现单个INTx#线，则称为INTA#；如果它实现两条线，则称为INTA#和INTB#；等等对于多功能设备，所有功能都可以使用相同的INTx#线，或者每个功能都可以有自己的（最多四个功能），或者它们的任意组合。单个函数不能在多个INTx#线上生成中断请求。67-6F 103-111由DOS保留与实模式相同70 112 IRQ8实时时钟71 113 IRQ9重定向至IRQ2 72 114 IRQ10未分配73 115 IRQ11未分配74 116 IRQ12鼠标75 117 IRQ13数学协处理器76 118 IRQ14 AT硬盘77 119 IRQ15闪存驱动器78-7F 120-127由DOS保留同实模式80-F0 128-240由BASIC保留与实模相同F1-FF 241-255由DOS保留模式表2-4 PC中断矢量表（续）中断编号IRQ LINE REAL Mode PROTECTED Mode HEX DEC 46 2 VMIVME-7750产品手册从属PIC通过BIOS定义的线路接受VME中断。BIOS根据哪个系统需要使用中断线来定义要使用的中断线。PCI设备中断图基于PCI总线的外部设备包括PMC站点、以太网控制器和PCI到VME桥。默认BIOS将这些外部设备映射到PCI中断请求
(Continued) IRQ AT FUNCTION COMMENTS 44 2 VMIVME-7750 Product Manual 14 20 BIOS Comm I/O Same as Real Mode 15 21 BIOS Cassette Tape I/O Same as Real Mode 16 22 BIOS Keyboard I/O Same as Real Mode 17 23 BIOS Printer I/O Same as Real Mode 18 24 ROM BASIC Entry Point Same as Real Mode 19 25 Bootstrap Loader Same as Real Mode 1A 26 Time of Day Same as Real Mode 1B 27 Control/Break Handler Same as Real Mode 1C 28 Timer Control Same as Real Mode 1D 29 Video Parameter Table Pntr Same as Real Mode 1E 30 Floppy Parm Table Pntr Same as Real Mode 1F 31 Video Graphics Table Pntr Same as Real Mode 20 32 DOS Terminate Program Same as Real Mode 21 33 DOS Function Entry Point Same as Real Mode 22 34 DOS Terminate Handler Same as Real Mode 23 35 DOS Control/Break Handler Same as Real Mode 24 36 DOS Critical Error Handler Same as Real Mode 25 37 DOS Absolute Disk Read Same as Real Mode 26 38 DOS Absolute Disk Write Same as Real Mode 27 39 DOS Program Terminate, Stay Resident Same as Real Mode 28 40 DOS Keyboard Idle Loop Same as Real Mode 29 41 DOS CON Dev. Raw Output Same as Real Mode 2A 42 DOS 3.x+ Network Comm Same as Real Mode 2B 43 DOS Internal Use Same as Real Mode 2C 44 DOS Internal Use Same as Real Mode 2D 45 DOS Internal Use Same as Real Mode 2E 46 DOS Internal Use Same as Real Mode 2F 47 DOS Print Spooler Driver Same as Real Mode 30-60 48-96 Reserved by DOS Same as Real Mode 61-66 97-102 User Available Same as Real Mode Table 2-4 PC Interrupt Vector Table (Continued) INTERRUPT NO. IRQ LINE REAL MODE PROTECTED MODE HEX DEC 45 Interrupts 2 PCI Interrupts Interrupts on Peripheral Component Interconnect (PCI) Local Bus are optional and defined as “level sensitive,” asserted low (negative true), using open drain output drivers. The assertion and de-assertion of an interrupt line, INTx#, is asynchronous to CLK. A device asserts its INTx# line when requesting attention from its device driver. Once the INTx# signal is asserted, it remains asserted until the device driver clears the pending request. When the request is cleared, the device de-asserts its INTx# signal. PCI defines one interrupt line for a single function device and up to four interrupt lines for a multifunction device or connector. For a single function device, only INTA# may be used while the other three interrupt lines have no meaning. Figure 2-1 on page 47 depicts the VMIVME-7750 interrupt logic pertaining to VME operations and the PMC site. Any function on a multifunction device can be connected to any of the INTx# lines. The Interrupt Pin register defines which INTx# line the function uses to request an interrupt. If a device implements a single INTx# line, it is called INTA#; if it implements two lines, they are called INTA# and INTB#; and so forth. For a multifunction device, all functions may use the same INTx# line, or each may have its own (up to a maximum of four functions), or any combination thereof. A single function can never generate an interrupt request on more than one INTx# line. 67-6F 103-111 Reserved by DOS Same as Real Mode 70 112 IRQ8 Real Time Clock 71 113 IRQ9 Redirect to IRQ2 72 114 IRQ10 Not Assigned 73 115 IRQ11 Not Assigned 74 116 IRQ12 Mouse 75 117 IRQ13 Math Coprocessor 76 118 IRQ14 AT Hard Drive 77 119 IRQ15 Flash Drive 78-7F 120-127 Reserved by DOS Same as Real Mode 80-F0 128-240 Reserved for BASIC Same as Real Mode F1-FF 241-255 Reserved by DOS Same as Real Mode Table 2-4 PC Interrupt Vector Table (Continued) INTERRUPT NO. IRQ LINE REAL MODE PROTECTED MODE HEX DEC 46 2 VMIVME-7750 Product Manual The slave PIC accepts the VME interrupts through lines that are defined by the BIOS. The BIOS defines which interrupt line to utilize depending on which system requires the use of the line. PCI Device Interrupt Map The PCI bus-based external devices include the PMC sites, Ethernet controller and the PCI-to-VME bridge. The default BIOS maps these external devices to the PCI Interrupt Request
