Renesas M3T-MR100 用户手册

   

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MR100's interrupt handlers consist of kernel interrupt handlers and non-kernel interrupt handlers. 

The following shows the definition of each type of interrupt handler. 

• 

Kernel interrupt handler 

An interrupt handler whose interrupt priority level is lower than a kernel interruption mask level is called kernel 
interrupt handler. That is, interruption priority level is from 1 to system_IPL. 
A service call can be issued within a kernel interrupt handler. However, interrupt is delayed until it becomes re-
ceivable the kernel interrupt handler generated during service call processing. 

• 

Non-kernel interrupt handler 

An interrupt handler whose interrupt priority level is higher than a kernel interrupt mask level is called non-kernel 
interrupt handler. That is, interruption priority level is from system_IPL+1 to 7.   
A service call cannot be issued within non-kernel interrupt handler. However, the non-kernel interrupt handler is 
able to be recieved during service call processing, even if it is the section where it is not able to receive a kernel 
interrupt handler: 
 

Figure 3.22 shows the relationship between the non-kernel interrupt handlers and kernel interrupt handlers where the kernel 
mask level is set to 3. 

 

High 

Low

0   1   2   3 

4   5   6   7 

Kernel 

Interrupt handler 

Non-kernel

Interrupt handler 

Kernel mask level 

 

 

Non-maskable interrupt ( ex. NMI interrupt ,Watchdog Timer interrupt) are treated as a non-kernel interrupt handler.