Comments; Blank Lines - Epson S5U1C63000A User Manual

Cmos 4-bit single chip microcomputer manual
Table of Contents

Advertisement

CHAPTER 4: ASSEMBLER
Restrictions
• The maximum number of characters of a symbol is 259 (not including colon). If this number is ex-
ceeded, an error will result.
• Only the following characters can be used:
A–Z a–z _ 0–9 ?
• A symbol cannot begin with a numeral.
Examples: ;OK
FOO:
L1:
.set
.comm
• Since symbols are case sensitive by default, uppercase and lowercase are discriminated. When refer-
encing a defined symbol, use the characters exactly the same as the defined symbol.
Examples: _Abcd:
However, symbols will be case insensitive if the -c option is specified.
• The symbol masks are effective only on the defined symbols. If a symbol mask is applied to a numeric
value, an error will result.
• If a symbol mask is omitted, the lower bits effective for that instruction will be used. However, if the
bit value does not fall within the instruction range, an error or warning will be issued.
• Symbols and symbol masks cannot be used on 4-bit immediate values.

4.5.4 Comments

Comments are used to describe a series of routines, or the meaning of each statement. Comments cannot
comprise part of coding.
Definition of comment
A character string beginning with a semicolon (;) and ending with a line feed code (LF) is interpreted
as a comment. Not only ASCII characters, but also other non-ASCII characters can be used to describe
a comment.
Examples: ;This line is a comment line.
LABEL:
ld
Restrictions
• A comment is allowed up to 259 characters, including a semicolon (;), spaces before, after and inside
the comment, and a return/line feed code.
• When a comment extends to several lines, each line must begin with a semicolon.
Examples: ;These are
comment lines.
;These are
; comment lines.

4.5.5 Blank Lines

This assembler also allows a blank line containing only a return/line feed code. It need not be made into a
comment line using a semicolon.
56
IO
0xfff0
BUF
4
:
jr
_ABCD
;This is the comment for LABEL.
%a,%b
;This is the comment for the instruction on the left.
... The second line will not be regarded as a comment. An error will
result.
... Both lines will be regarded as comments.
;Error
1lable:
L 1:
.set
#IO
0xfff0
.lcomm
1st_BUF
2
... Does not jump to _Abcd
EPSON
(S1C63 FAMILY ASSEMBLER PACKAGE)
S5U1C63000A MANUAL

Advertisement

Table of Contents
loading

Table of Contents