TI C66x DSP中断类型及其优先级

There are four types of interrupts on the CPU.

• Reset

• Maskable

• Nonmaskable

• Exception（异常也可视为中断）

These first three types are differentiated by their priorities. The reset interrupt has the highest priority and corresponds to the RESET signal. The nonmaskable interrupt (NMI) has the second highest priority and corresponds to the NMI signal. The lowest priority interrupts are interrupts 4-15 corresponding to the INT4-INT15 signals. RESET, NMI, and some of the INT4-INT15 signals are mapped to pins on C6000 devices.

The CPU supports exceptions as another type of interrupt. When exceptions are enabled, the NMI input behaves as an exception.

Priority    Interrupt Name    Interrupt Type
Highest     Reset                 Reset
                   NMI                     Nonmaskable
                   INT4                   Maskable
                   INT5                   Maskable
                   INT6                   Maskable
                   INT7                   Maskable
                   INT8                   Maskable
                   INT9                   Maskable
                   INT10                 Maskable
                   INT11                 Maskable
                   INT12                 Maskable
                   INT13                 Maskable
                   INT14                 Maskable
Lowest     INT15                  Maskable

在基于OSEck RTOS的TI C66x DSP系统中， 这些中断的优先级将高于所有user定义的APP进程（即prioritied process），从而使中断能够在第一时间处理。