C166: Declaring bdata and sbit Variables

Information in this article applies to:

• C166 Version 5 and later

QUESTION

I'm trying to use the sbit keyword to create a bit in a bdata variable, but I can't seem to get the example program to work:

void main (void)
  {
  bdata int ibase;
  sbit mybit0 = ibase ^ 0;
  .
  .
  .
  mybit0 = 1;
}

I get the following compiler messages:

*** WARNING C189: 'ibase': storage class changed to 'static'
*** ERROR C25: syntax error near 'sbit'

How do I declare local bits?

ANSWER

As stated in the C166 User's Guide, the sbit notation can be only used in combination with global variables. This means that you need to define the variable at file level.

However, you may use bit-field structures instead, since the usage of bit-field structures is not restricted.

Example:

struct b {
  unsigned int  _0: 1;
  unsigned int  _1: 1;
  unsigned int  _2: 1;
  unsigned int  _3: 1;
  unsigned int  _4: 1;
  unsigned int  _5: 1;
  unsigned int  _6: 1;
  unsigned int  _7: 1;
  unsigned int  _8: 1;
  unsigned int  _9: 1;
  unsigned int _10: 1;
  unsigned int _11: 1;
  unsigned int _12: 1;
  unsigned int _13: 1;
  unsigned int _14: 1;
  unsigned int _15: 1;
};

void main (void) {
  static struct b bdata ibase;

  ibase_1 = 1;
}

MORE INFORMATION

• Refer to bdata in the C166 User's Guide.

SEE ALSO

• C166: Using sbit in Embedded C++

Last Reviewed: Thursday, February 25, 2021