NI PXI-8423串行板卡，PXI-8423说明书文档

中断确认映射MC68030将中断确认周期与通过将二进制值%1111放在A19上的其他CPU空间周期-A16。它还指定了使用A03-A01。中断处理程序选择其中的哪个设备正在确认级别。请参阅第5章中的中断处理程序。VMEbus内存映射以下段落描述了MVME147的映射VMEbus masters查看的资源。

NI PXI-8423串行板卡MVME147板载DRAM、VMEchip全局寄存器和VMEbus中断器响应VMEbus主机的访问。不MVME147上的其他设备响应此类访问。VMEbus访问MVME147板载DRAM

当VMEbus主机访问MVME147板载DRAM时，它必须使用由控制寄存器选择的地址修饰符执行此操作在VMEchip和由控制寄存器选择的基址中在PCC中。参见表3-6。CPU地址空间MVME147响应两种类型的CPU空间周期：❏ 协处理器❏ 中断确认MC68030能够生成其他类型的CPU空间周期（使用断点确认、访问级别控制或移动指令），但MVME147没有回应他们。协处理器寄存器映射MC68882是MVME147上唯一的协处理器。地图每当MPU执行Cp ID为%001（FC2-FC0=%111和A19）的协处理器循环-A13=%0010001）。MC68882寄存器由A4-A0选择为如表3-5所示。

Interrupt Acknowledge Map

The MC68030 distinguishes interrupt acknowledge cycles from

other CPU space cycles by placing the binary value %1111 on A19-

A16. It also specifies the level that is being acknowledged using

A03-A01. The interrupt handler selects which device within that

level is being acknowledged. Refer to Interrupt Handler in Chapter 5.

VMEbus Memory Map

The following paragraphs describe the mapping of MVME147

resources as viewed by VMEbus masters.

The MVME147 onboard DRAM, VMEchip global registers, and

VMEbus interrupter respond to accesses by VMEbus masters. No

other devices on the MVME147 respond to such accesses.

VMEbus Accesses to MVME147 Onboard DRAM

When a VMEbus master accesses the MVME147 onboard DRAM, it

must do so using the address modifier selected by a control register

in the VMEchip and the base address selected by a control register

in the PCC. Refer to Table 3-6.CPU Address Space

The MVME147 responds to two types of CPU space cycles:

❏ Coprocessor

❏ Interrupt acknowledge

The MC68030 is capable of generating other types of CPU space

cycles (using breakpoint acknowledge, access level control, or

MOVES instructions), but the MVME147 has no devices that

respond to them.

Coprocessor Register Map

The MC68882 is the only coprocessor on the MVME147. The map

decoder selects the MC68882 any time the MPU executes a

coprocessor cycle with Cp-ID of %001 (FC2-FC0 =%111 and A19-

A13 =%0010001). The MC68882 registers are selected by A4-A0 as

shown in Table 3-5.