Chapter 6 Using Configurator
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specified at the same time.
[Precautions]
1. Regarding the method for specifying a register bank
A kernel (OS dependent) interrupt handler that uses register bank 1 cannot be written in C language. Such an
interrupt handler can only be written in assembly language. When writing in assembly language, make sure the
statements at the entry and exit of the interrupt handler are written as shown below.
(Always be sure to clear the B flag before issuing the ret_int service call.)
Example: interrupt;
fset B
fclr B
ret_int
Internally in the MR308 kernel, register banks are not switched over.
2. Regarding the method for specifying a high-speed interrupt
To ensure an effective use of high-speed interrupts, make sure the registers of register bank 1 are used in the
high-speed interrupt. Note also that high-speed interrupts cannot be used for the kernel (OS dependent) inter-
rupt handler.
3. Do not use NMI and watchdog timer interrupts in the kernel (OS dependent) interrupt.