Fujitsu F2MC-16L Series, Руководство пользователя

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CHAPTER 2 Developing Application Systems
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Initialize handler
The initialize handler is called by the kernel. The handler initializes the devices used by the
kernel (such as the timer device used for the system clock) and the devices used in the user
program (such as I/O devices).
The initialize handler can use those system calls that can be called from REALOS/907 task
independent portions.
The REALOS/907 initialize handler performs the following processing.
❍ Initialize the interrupt controller
Initializes the interrupt controller. Initialize the interrupt controller according to the structure
of the target hardware.
❍ Initialize the timer device
Initializes the interval timer that generates the fixed period interrupts used by the system
clock (set the period to suit wai_tsk and the cyclic handler). In general, set a period of 1ms
(at CPU operation frequency of 16MHz) or more.
In the configurator, assign the interval timer interrupt handler to the corresponding
interrupt vector number.
❍
Initialize user devices
Initialize the devices used by the user program. You can also uwse this routine to perform
system initialization by using software as well as hardware.
❍
Start tasks
As all tasks are initially in the DORMANT state, start the initial tasks from this routine.
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System clock timer interrupt handler
The timer interrupt handler for the system clock is the system clock interrupt handler used by
REALOS/907. The handler performs the timer interrupt processing required by the user target
hardware (such as clearing the interrupt) then calls the REALOS/907 system clock processing.
The r97_sclk_hdr label is defined for the system clock processing and is declared globally. Use
this label to jump to the system clock processing.
In the configurator, assign the label for the system clock timer interrupt handler to the interrupt
number corresponding to the timer interrupt on the user target hardware.
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