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Bitwise logical AND stores in a bit ....

Arnaud DELEULE

Hi,

I get a curious result when compiling such a following code :

typedef union  {

  unsigned char                cCtrlFullByte;

  struct {
    unsigned char  bEnable          : 1;
    unsigned char  cUnused          : 7;

  }  cCtrlStruct;
} CtrlUnion;

void main (void)  {

    unsigned char  dummy = 0x55;
    CtrlUnion  xdata    bitUnion;

    bitUnion.cCtrlStruct.bEnable = dummy & 0x40;

    return;
}

It results in :
MOV A,#0x55
ANL A,#0x00
MOV R7,A
MOV DPTR, #0x0000
MOVX A,@DPTR
ANL A,#0xFE
ORL A,R7
MOVX @DPTR, A

I thought that the bit result of bitwise logical AND is 1 if result is not 0, else 0.
It seems that I didn't understand ANSI the same way than Keil compiler ? Am I wrong ?

Arnaud DELEULE

0