Renesas M3T-MR100 用户手册

   

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The system runs in either context state, "task context" or "non-task context." The differences between the task content and 
non-task context are shown in Table 3-1. Task Context and Non-task Context. 

 

 

Task context 

Non-task context 

Invocable service call 

Those that can be invoked from 
task context 

Those that can be invoked from 
non-task context 

Task scheduling 

Occurs when the queue state has 
changed to other than dispatch dis-
abled and CPU locked states. 

It does not occur. 

Stack 

User stack 

System stack 

 

The processes executed in non-task context include the following. 

A program that starts upon hardware interruption is called the interrupt handler. The MR100 is not concerned in interrupt 
handler activation. Therefore, the interrupt handler entry address is to be directly written into the interrupt vector table.   

There are two interrupt handlers: Non-kernel interrupts (OS independent interrupts) and kernel interrupts (OS dependent 
interrupts). For details about each type of interrupt, refer to Section 3.6. 

The system clock interrupt handler (isig_tim) is one of these interrupt handlers. 

The cyclic handler is a program that is started cyclically every preset time. The set cyclic handler may be started or stopped 
by the sta_cyc(ista_cyc) or stp_cyc(istp_cyc) service call. 

The cyclic handler startup time of day is unaffected by a change in the time of day by set_tim(iset_tim).   

The alarm handler is a handler that is started after the lapse of a specified relative time of day. The alarm handler startup 
time of day is determined by a time of day relative to the time of day set by sta_alm(ista_alm), and is unaffected by a 
change in the time of day by set_tim(iset_tim). 

 

The cyclic and alarm handlers are invoked by a subroutine call from the system clock interrupt (timer interrupt) handler. 
Therefore, cyclic and alarm handlers operate as part of the system clock interrupt handler. Note that when the cyclic or 
alarm handler is invoked, it is executed in the interrupt priority level of the system clock interrupt.