The CC-RH can disable the maskable interrupts in a C source.

This can be done in the following two ways.

The "di instruction" and "ei instruction" of the assembler instruction can be used to disable an interrupt locally in a function described in C language. However, the CC-RH has functions that can control the interrupts in a C language source.

void func1(void) {

          :

        __DI();

        /*Describe processing to be performed with interrupt disabled.*/

        __EI();

          :

}

_func1:

        -- prologue code

          :

        di

        -- processing to be performed with interrupt disabled

        ei

          :

        -- epilogue code

        jmp     [lp]

The CC-RH has a "#pragma block_interrupt" directive that disables the interrupts of an entire function.

This directive is described as follows.

#pragma block_interrupt [(]function-name[)]

Describe functions that are described in the C language. In the case of a function, "void func1() {}", specify "func1".

The interrupt to the function specified by "function-name" above is disabled. As explained in "(1) Locally disabling interrupt in function", __ DI()" can be described at the beginning of a function and "__ EI()", at the end. In this case, however, an interrupt to the prologue code and epilogue code output by the CC-RH cannot be disabled or enabled, and therefore, interrupts in the entire function cannot be disabled.

Using the #pragma block_interrupt directive, interrupts are disabled immediately before execution of the prologue code, and enabled immediately after execution of the epilogue code. As a result, interrupts in the entire function can be disabled.

#pragma block_interrupt func1

void func1(void) {

          :

        /*Describe processing to be performed with interrupt disabled.*/

          :

}

_func1:

        di

        -- prologue code

          :

        -- processing to be performed with interrupt disabled

          :

        -- epilogue code

        ei

        jmp     [lp]

Note the following points when disabling interrupts in an entire function.