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2 service call – Renesas Emulator System M3T-MR100 User Manual

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3.2 Service Call

How does the programmer use the kernel functions in a program?

First, it is necessary to call up kernel function from the program in some way or other. Calling a kernel function is referred
to as a service call. Task activation and other processing operations can be initiated by such a service call (See Figure 3.9).

Key input

Task

Kernel

Remote control

task

Service call

Task switching

Figure 3.9 Service call

This service call is realized by a function call when the application program is written in C language, as shown below.

act_tsk(ID_main,3);

Furthermore, if the application program is written in assembly language, it is realized by an assembler macro call, as shown
below.

act_tsk #ID_main