CC78K0S Datasheet, PDF (361/520 Pages) NEC – C Compiler Ver.1.30 or Later Language

CHAPTER 11 EXTENDED FUNCTIONS
Bit Field Declaration
Bit field declaration
COMPATIBILITY
<From another C compiler to this C compiler>
• The source program need not be modified.
• Change the type specifier to use unsigned char as the type specifier.
<From this C compiler to another C compiler>
• The source program need not be modified if unsigned char is not used as a type specifier.
• Change unsigned char, if it is used as a type specifier, into unsigned int.
(2) Allocation direction of bit field
FUNCTION
• The direction in which a bit field is to be allocated is changed and the bit field is allocated from the MSB side
when the -RB option is specified.
• If the -RB option is not specified, the bit field is allocated from the LSB side.
USAGE
• Specify the -RB option at compile time to allocate the bit field from the MSB side.
• Do not specify the option to allocate the bit field from the LSB side.
EXAMPLE 1
(Bit field declaration)
struct t {
unsigned char A:1;
unsigned char B:1;
unsigned char C:1;
unsigned char D:1;
unsigned char E:1;
unsigned char F:1;
unsigned char G:1;
unsigned char H:1;
};
User’s Manual U14872EJ1V0UM
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