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DISABLE Compiler Directive








This directive may not be specified on the command line.


The DISABLE directive instructs the compiler to generate code that disables all interrupts for the duration of a function. This directive must be specified with #pragma immediately before the function declaration. The DISABLE directive applies to one function only and must be re-specified for each new function.


  • The DISABLE directive must be specified using #pragma only and may not be specified on the command line.
  • The DISABLE directive may be specified more than once in a source file but must be specified for each function that is to execute with interrupts disabled.
  • A function with disabled interrupts may not have a return type of bit.
  • The DISABLE directive has no impact on the main function, since typically all interrupts are disabled and no function return occurs.
stmt level    source
   1          typedef unsigned char  uchar;
   3          #pragma disable   /* Disable Interrupts */
   4          uchar dfunc (uchar p1, uchar p2)  {
   5   1        return (p1 * p2 + p2 * p1);
   6   1      }
        ; FUNCTION _dfunc (BEGIN)
0000 D3         SETB  C
0001 10AF01     JBC   EA,?C0002
0004 C3         CLR   C
0005  ?C0002:
0005 C0D0       PUSH  PSW
;---- Variable 'p1' assigned to register 'R7' ----
;---- Variable 'p2' assigned to register 'R5' ----
                ; SOURCE LINE # 4
                ; SOURCE LINE # 5
0007 ED         MOV   A,R5
0008 8FF0       MOV   B,R7
000A A4         MUL   AB
000B 25E0       ADD   A,ACC
000D FF         MOV   R7,A
                ; SOURCE LINE # 6
000E  ?C0001:
000E D0D0       POP   PSW
0010 92AF       MOV   EA,C
0012 22         RET
        ; FUNCTION _dfunc (END)
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