CHAPTER 4: ASSEMBLER

CHAPTER 4 ASSEMBLER

This chapter describes the functions of the assembler as63 and grammar involved with the creation of assembly source files.

4.1 Functions

The assembler as63 is a tool that constitutes the core of this software package. It assembles (translates) assembly source files and creates object files in the machine language.

The functions and features of the assembler are summarized below:

Allows absolute and relocatable sections mixed in one source.

Allows to develop programs in multiple sources by creating relocatable object files that can be com- bined by the linker.

Can add source debugging information for source debugging on the debugger.

Upper compatible with the old S1C63 preprocessor and assembler.

The assembler provides the following additional functions as well as the basic assembly functions:

Macro definition and macro invocation

Definition of Define name

Operators

Insertion of other file

Conditional assembly

The assembler processes source files in two stages: preprocessing stage and assembling stage. The preprocessing stage expands the additional function part described in the source file to mnemonics that can be assembled, and delivers them to a temporary file (preprocessed file). The assembling stage assemble the preprocessed file to convert the source codes into the machine codes.

4.2 Input/Output Files

Assembly source file

 

 

 

file.s

 

 

 

Assembler

 

 

 

as63

 

 

file.lst

file.o

file.ms

file.err

Relocatable

Object file

Preprocessed

Error file

list file

 

source file

 

to Linker

Fig. 4.2.1 Flow chart

4.2.1 Input File

Assembly source file

File format: Text file

File name: <File name>.s

<File name>.ms (A preprocessed source file created by the assembler or disassembler.) Description: File in which a source program is described. If the file extension is omitted, the

assembler finds a source file that has the specified file name and an extension ".s". Note: When a ".s" source file is specified, it will be processed in the preprocessing stage

and then the assembling stage. When a ".ms" source file is specified, it will be processed only in the assembling stage. Therefore, ".ms" files cannot include preprocessor instructions.

S5U1C63000A MANUAL

EPSON

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(S1C63 FAMILY ASSEMBLER PACKAGE)