CC78K4 Datasheet, PDF (19/523 Pages) NEC – CC78K4 Ver.2.30 or Later, C Compiler Language

CHAPTER 1 GENERAL
The CC78K4 C Compiler is a language processing program that converts a source program written in the C
language for the 78K/IV Series or ANSI-C into machine language. By the CC78K4 C compiler, object files or
assembler source files for the 78K/IV Series can be obtained.
1.1 C Language and Assembly Language
To have a microcontroller do its job, programs and data are necessary. These programs and data must be written
by a human being (programmer) and stored in the memory section of the microcontroller. Programs and data that
can be handled by the microcontroller are nothing but a set or combination of binary numbers that is called machine
language.
An assembly language is a symbolic language characterized by one-to-one correspondence of its symbolic
(mnemonic) statements with machine language instructions. Because of this one-to-one correspondence, the
assembly language can provide the computer with detailed instructions (for example, to improve I/O processing
speed). However, this means that the programmer must instruct each and every operation of the computer. For this
reason, it is difficult for him or her to understand the logic structure of the program at a glance, increasing the
likelihood of to make errors in coding.
High-level languages were developed as substitutes for such assembly languages. The high-level languages
include a language called C that allows the programmer to write a program without regard to the architecture of the
computer.
Compared with assembly language programs, it can be said that programs written in C have an easy-to-
understand logic structure.
C has a rich set of parts called functions for use in creating programs. In other words, the programmer can write a
program by combining these functions.
User’s Manual U15556EJ1V0UM
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