CC78K4 Datasheet, PDF (445/523 Pages) NEC – CC78K4 Ver.2.30 or Later, C Compiler Language

CHAPTER 11 EXTENDED FUNCTIONS
(41) Three-byte address reference/generation function
Three-Byte Address Reference/Generation Function
#pragma addraccess
FUNCTION
• A code that references the highest byte and the lower 2 bytes of a 3-byte address, and a code that generates
a 3-byte address from the value of the highest byte and the lower 2 bytes are output to an object directly with
inline expansion and an object file is created.
• If the #pragma directive is not added, the three-byte address reference/generation function is regarded as an
ordinary function.
EFFECT
• Three-byte address reference/generation can be performed with a short code without using a complex cast
description.
USAGE
• Describe the #pragma addraccess directive at the beginning of the C source.
• Describe the #pragma addraccess directive in the C source in the same manner as a function call.
• The following items can be described before the #pragma addraccess directive.
(1) Comments
(2) Other #pragma directives
(3) Among the preprocessing directives, those that do not generate a variable definition/reference or
function definition/reference.
• The keywords following #pragma addraccess can be described in either uppercase or lowercase letters.
The following three names can be used for the three-byte address reference/generation function name.
• FP_SEG
• FP_OFF
• MK_FP
[List of function names for three-byte address reference/generation]
(1) unsigned char FP_SEG(void *addr);
The value of the most significant byte of a three-byte address pointed by addr is obtained.
(2) unsigned int FP_OFF(void *addr);
The values of the lower 2 bytes of a three-byte address pointed by addr are obtained.
(3) void *MK_FP(unsigned char seg, unsigned int offset);
The address value of the three-byte address having the value pointed by seg as the most significant byte, and
the value pointed by offset as the lower 2 bytes.
User’s Manual U15556EJ1V0UM
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