-<!doctype linuxdoc system>
+<!doctype linuxdoc system> <!-- -*- text-mode -*- -->
<article>
<title>ca65 Users Guide
-U Mark unresolved symbols as import
-V Print the assembler version
-W n Set warning level n
+ -d Debug mode
-g Add debug info to object file
-h Help (this text)
-i Ignore case of symbols
--cpu type Set cpu type
--create-dep name Create a make dependency file
--create-full-dep name Create a full make dependency file
+ --debug Debug mode
--debug-info Add debug info to object file
--feature name Set an emulation feature
- --forget-inc-paths Forget include search paths
--help Help (this text)
--ignore-case Ignore case of symbols
--include-dir dir Set an include directory search path
--large-alignment Don't warn about large alignments
--listing name Create a listing file if assembly was ok
--list-bytes n Maximum number of bytes per listing line
- --macpack-dir dir Set a macro package directory
--memory-model model Set the memory model
--pagelength n Set the page length for the listing
+ --relax-checks Relax some checks (see docs)
--smart Enable smart mode
--target sys Set the target system
--verbose Increase verbosity
Set the default for the CPU type. The option takes a parameter, which
may be one of
- 6502, 65SC02, 65C02, 65816, sunplus, sweet16, HuC6280
-
- The sunplus cpu is not available in the freeware version, because the
- instruction set is "proprietary and confidential".
+ 6502, 65SC02, 65C02, 65816, sweet16, HuC6280
<label id="option-create-dep">
information to the assembler.
+ <tag><tt>-d, --debug</tt></tag>
+
+ Enables debug mode, something that should not be needed for mere
+ mortals:-)
+
+
<label id="option--feature">
<tag><tt>--feature name</tt></tag>
command for a list of emulation features.
- <label id="option--forget-inc-paths">
- <tag><tt>--forget-inc-paths</tt></tag>
-
- Forget the builtin include paths. This is most useful when building
- customized assembler modules, in which case the standard header files should
- be ignored.
-
-
<label id="option-g">
<tag><tt>-g, --debug-info</tt></tag>
number of printed bytes.
- <label id="option--macpack-dir">
- <tag><tt>--macpack-dir dir</tt></tag>
-
- This options allows to specify a directory containing macro files that are
- used instead of the builtin images when a <tt><ref id=".MACPACK"
- name=".MACPACK"></tt> directive is encountered. If <tt>--macpack-dir</tt>
- was specified, a <tt>.mac</tt> extension is added to the package name and
- the resulting file is loaded from the given directory. This is most useful
- when debugging the builtin macro packages.
-
-
<label id="option-mm">
<tag><tt>-mm model, --memory-model model</tt></tag>
id=".PAGELENGTH" name=".PAGELENGTH"></tt> directive for more information.
+ <label id="option--relax-checks">
+ <tag><tt>--relax-checks</tt></tag>
+
+ Relax some checks done by the assembler. This will allow code that is an
+ error in most cases and flagged as such by the assembler, but can be valid
+ in special situations.
+
+ Examples are:
+<itemize>
+<item>Short branches between two different segments.
+<item>Byte sized address loads where the address is not a zeropage address.
+</itemize>
+
+
<label id="option-s">
<tag><tt>-s, --smart-mode</tt></tag>
Normal include files are searched in the following places:
<enum>
-<item>The current directory.
-<item>A compiled-in directory, which is often <tt>/usr/lib/cc65/asminc</tt>
- on Linux systems.
+<item>The current file's directory.
+<item>Any directory added with the <tt/<ref id="option-I" name="-I">/ option
+on the command line.
<item>The value of the environment variable <tt/CA65_INC/ if it is defined.
<item>A subdirectory named <tt/asminc/ of the directory defined in the
environment variable <tt/CC65_HOME/, if it is defined.
-<item>Any directory added with the <tt/<ref id="option-I" name="-I">/ option
-on the command line.
+<item>An optionally compiled-in directory.
</enum>
Binary include files are searched in the following places:
<enum>
-<item>The current directory.
+<item>The current file's directory.
<item>Any directory added with the <tt/<ref id="option--bin-include-dir"
name="--bin-include-dir">/ option on the command line.
</enum>
<tt><ref id=".PC02" name=".PC02"></tt> command was given).
<item>all valid 65618 mnemonics when in 65816 mode (after the
<tt><ref id=".P816" name=".P816"></tt> command was given).
-<item>all valid SunPlus mnemonics when in SunPlus mode (after the
- <tt><ref id=".SUNPLUS" name=".SUNPLUS"></tt> command was given).
</itemize>
</verb></tscreen>
-<label id=".SET">
+<label id="variables">
<sect1>Numeric variables<p>
Within macros and other control structures (<tt><ref id=".REPEAT"
prefer the "cheap" local labels). Nevertheless, unnamed labels are
convenient in some situations, so it's your decision.
+<bf/Note:/ <ref id="scopes" name="Scopes"> organize named symbols, not
+unnamed ones, so scopes don't have an effect on unnamed labels.
+
+
<sect1>Using macros to define labels and constants<p>
-While there are drawbacks with this approach, it may be handy in some
-situations. Using <tt><ref id=".DEFINE" name=".DEFINE"></tt>, it is
-possible to define symbols or constants that may be used elsewhere. Since
-the macro facility works on a very low level, there is no scoping. On the
-other side, you may also define string constants this way (this is not
+While there are drawbacks with this approach, it may be handy in a few rare
+situations. Using <tt><ref id=".DEFINE" name=".DEFINE"></tt>, it is possible
+to define symbols or constants that may be used elsewhere. One of the
+advantages is that you can use it to define string constants (this is not
possible with the other symbol types).
+Please note: <tt/.DEFINE/ style macros do token replacements on a low level,
+so the names do not adhere to scoping, diagnostics may be misleading, there
+are no symbols to look up in the map file, and there is no debug info.
+Especially the first problem in the list can lead to very nasty programming
+errors. Because of these problems, the general advice is, <bf/NOT/ do use
+<tt/.DEFINE/ if you don't have to.
+
Example:
<tscreen><verb>
<tscreen><verb>
.struct Point ; Struct size = 4
xcoord .word
- xcoord .word
+ ycoord .word
.endstruct
P: .tag Point ; Declare a point
<sect1><tt>.CHARMAP</tt><label id=".CHARMAP"><p>
Apply a custom mapping for characters. The command is followed by two
- numbers in the range 1..255. The first one is the index of the source
- character, the second one is the mapping. The mapping applies to all
- character and string constants when they generate output, and overrides
- a mapping table specified with the <tt><ref id="option-t" name="-t"></tt>
+ numbers. The first one is the index of the source character (range 1..255),
+ the second one is the mapping (range 0..255). The mapping applies to all
+ character and string constants when they generate output, and overrides a
+ mapping table specified with the <tt><ref id="option-t" name="-t"></tt>
command line switch.
Example:
Start a define style macro definition. The command is followed by an
identifier (the macro name) and optionally by a list of formal arguments
in braces.
+
+ Please note that <tt/.DEFINE/ shares most disadvantages with its C
+ counterpart, so the general advice is, <bf/NOT/ do use <tt/.DEFINE/ if you
+ don't have to.
+
See also the <tt><ref id=".UNDEFINE" name=".UNDEFINE"></tt> command and
section <ref id="macros" name="Macros">.
and unions"">.
+<sect1><tt>.ENDUNION</tt><label id=".ENDUNION"><p>
+
+ Ends a union definition. See the <tt/<ref id=".UNION" name=".UNION">/
+ command and the separate section named <ref id="structs" name=""Structs
+ and unions"">.
+
+
<sect1><tt>.ENUM</tt><label id=".ENUM"><p>
Start an enumeration. This directive is very similar to the C <tt/enum/
at character is not allowed to start an identifier, even with this
feature enabled.
- <tag><tt>c_comments</tt></tag>
+ <tag><tt>c_comments</tt><label id="c_comments"></tag>
Allow C like comments using <tt>/*</tt> and <tt>*/</tt> as left and right
comment terminators. Note that C comments may not be nested. There's also a
dollar character is not allowed to start an identifier, even with this
feature enabled.
- <tag><tt>dollar_is_pc</tt></tag>
+ <tag><tt>dollar_is_pc</tt><label id="dollar_is_pc"></tag>
The dollar sign may be used as an alias for the star (`*'), which
gives the value of the current PC in expressions.
Note: Assignment to the pseudo variable is not allowed.
- <tag><tt>labels_without_colons</tt></tag>
+ <tag><tt>force_range</tt><label id="force_range"></tag>
+
+ Force expressions into their valid range for immediate addressing and
+ storage operators like <tt><ref id=".BYTE" name=".BYTE"></tt> and
+ <tt><ref id=".WORD" name=".WORD"></tt>. Be very careful with this one,
+ since it will completely disable error checks.
+
+ <tag><tt>labels_without_colons</tt><label id="labels_without_colons"></tag>
Allow labels without a trailing colon. These labels are only accepted,
if they start at the beginning of a line (no leading white space).
overridden. When using this feature, you may also get into trouble if
later versions of the assembler define new keywords starting with a dot.
- <tag><tt>loose_char_term</tt></tag>
+ <tag><tt>loose_char_term</tt><label id="loose_char_term"></tag>
Accept single quotes as well as double quotes as terminators for char
constants.
- <tag><tt>loose_string_term</tt></tag>
+ <tag><tt>loose_string_term</tt><label id="loose_string_term"></tag>
Accept single quotes as well as double quotes as terminators for string
constants.
- <tag><tt>missing_char_term</tt></tag>
+ <tag><tt>missing_char_term</tt><label id="missing_char_term"></tag>
Accept single quoted character constants where the terminating quote is
missing.
effect will only enable absolute mode for the current segment. Dito for
<tt><ref id=".RELOC" name=".RELOC"></tt>.
- <tag><tt>pc_assignment</tt></tag>
+ <tag><tt>pc_assignment</tt><label id="pc_assignment"></tag>
Allow assignments to the PC symbol (`*' or `$' if <tt/dollar_is_pc/
is enabled). Such an assignment is handled identical to the <tt><ref
removing the lines with the assignments may also be an option when porting
code written for older assemblers).
- <tag><tt>ubiquitous_idents</tt></tag>
+ <tag><tt>ubiquitous_idents</tt><label id="ubiquitous_idents"></tag>
Allow the use of instructions names as names for macros and symbols. This
makes it possible to "overload" instructions by defining a macro with the
same name. This does also make it possible to introduce hard to find errors
in your code, so be careful!
+ <tag><tt>underline_in_numbers</tt><label id="underline_in_numbers"></tag>
+
+ Allow underlines within numeric constants. These may be used for grouping
+ the digits of numbers for easier reading.
+ Example:
+ <tscreen><verb>
+ .feature underline_in_numbers
+ .word %1100001110100101
+ .word %1100_0011_1010_0101 ; Identical but easier to read
+ </verb></tscreen>
+
</descrip>
It is also possible to specify features on the command line using the
This command is often used to check if a macro parameter was given. Since an
empty macro parameter will evaluate to nothing, the condition will evaluate
- to FALSE if an empty parameter was given.
+ to TRUE if an empty parameter was given.
Example:
id=".RODATA" name=".RODATA"></tt>
+<sect1><tt>.SET</tt><label id=".SET"><p>
+
+ <tt/.SET/ is used to assign a value to a variable. See <ref id="variables"
+ name="Numeric variables"> for a full description.
+
+
<sect1><tt>.SETCPU</tt><label id=".SETCPU"><p>
Switch the CPU instruction set. The command is followed by a string that
specifies the CPU. Possible values are those that can also be supplied to
the <tt><ref id="option--cpu" name="--cpu"></tt> command line option,
- namely: 6502, 6502X, 65SC02, 65C02, 65816, sunplus and HuC6280. Please
- note that support for the sunplus CPU is not available in the freeware
- version, because the instruction set of the sunplus CPU is "proprietary
- and confidential".
+ namely: 6502, 6502X, 65SC02, 65C02, 65816and HuC6280.
See: <tt><ref id=".CPU" name=".CPU"></tt>,
<tt><ref id=".IFP02" name=".IFP02"></tt>,
Starts a struct definition. Structs are covered in a separate section named
<ref id="structs" name=""Structs and unions"">.
- See: <tt><ref id=".ENDSTRUCT" name=".ENDSTRUCT"></tt>
-
-
-<sect1><tt>.SUNPLUS</tt><label id=".SUNPLUS"><p>
-
- Enable the SunPlus instructions set. This command will not work in the
- freeware version of the assembler, because the instruction set is
- "proprietary and confidential".
-
- See: <tt><ref id=".P02" name=".P02"></tt>, <tt><ref id=".PSC02"
- name=".PSC02"></tt>, <tt><ref id=".PC02" name=".PC02"></tt>, and
- <tt><ref id=".P816" name=".P816"></tt>
+ See also: <tt><ref id=".ENDSTRUCT" name=".ENDSTRUCT"></tt>,
+ <tt><ref id=".ENDUNION" name=".ENDUNION"></tt>,
+ <tt><ref id=".UNION" name=".UNION"></tt>
<sect1><tt>.TAG</tt><label id=".TAG"><p>
section <ref id="macros" name="Macros">.
+<sect1><tt>.UNION</tt><label id=".UNION"><p>
+
+ Starts a union definition. Unions are covered in a separate section named
+ <ref id="structs" name=""Structs and unions"">.
+
+ See also: <tt><ref id=".ENDSTRUCT" name=".ENDSTRUCT"></tt>,
+ <tt><ref id=".ENDUNION" name=".ENDUNION"></tt>,
+ <tt><ref id=".STRUCT" name=".STRUCT"></tt>
+
+
<sect1><tt>.WARNING</tt><label id=".WARNING"><p>
Force an assembly warning. The assembler will output a warning message
.endmacro
</verb></tscreen>
- See also: <tt><ref id=".ERROR" name=".ERROR"></tt>
+ See also: <tt><ref id=".ERROR" name=".ERROR"></tt>,
<tt><ref id=".FATAL" name=".FATAL"></tt>,
<tt><ref id=".OUT" name=".OUT"></tt>
.endmacro
</verb></tscreen>
-But imagine what happens, if you use this macro twice? Since the label
-"Skip" has the same name both times, you get a "duplicate symbol" error.
-Without a way to circumvent this problem, macros are not as useful, as
-they could be. One solution is, to start a new lexical block inside the
-macro:
+But imagine what happens, if you use this macro twice? Since the label "Skip"
+has the same name both times, you get a "duplicate symbol" error. Without a
+way to circumvent this problem, macros are not as useful, as they could be.
+One possible solution is the command <tt><ref id=".LOCAL" name=".LOCAL"></tt>.
+It declares one or more symbols as local to the macro expansion. The names of
+local variables are replaced by a unique name in each separate macro
+expansion. So we can solve the problem above by using <tt/.LOCAL/:
+
+<tscreen><verb>
+ .macro inc16 addr
+ .local Skip ; Make Skip a local symbol
+ inc addr
+ bne Skip
+ inc addr+1
+ Skip: ; Not visible outside
+ .endmacro
+</verb></tscreen>
+
+Another solution is of course to start a new lexical block inside the macro
+that hides any labels:
<tscreen><verb>
.macro inc16 addr
.proc
- inc addr
+ inc addr
bne Skip
inc addr+1
Skip:
.endmacro
</verb></tscreen>
-Now the label is local to the block and not visible outside. However,
-sometimes you want a label inside the macro to be visible outside. To make
-that possible, there's a new command that's only usable inside a macro
-definition: <tt><ref id=".LOCAL" name=".LOCAL"></tt>. <tt/.LOCAL/ declares one
-or more symbols as local to the macro expansion. The names of local variables
-are replaced by a unique name in each separate macro expansion. So we could
-also solve the problem above by using <tt/.LOCAL/:
-
-<tscreen><verb>
- .macro inc16 addr
- .local Skip ; Make Skip a local symbol
- clc
- lda addr
- adc #$01
- sta addr
- bcc Skip
- inc addr+1
- Skip: ; Not visible outside
- .endmacro
-</verb></tscreen>
-
<sect1>C style macros<p>
don't like that, use classic macros instead:
<tscreen><verb>
- .macro message
+ .macro DEBUG message
.out message
.endmacro
</verb></tscreen>
beq Arg
bcc Arg
.endmacro
+
+ .macro bnz Arg
+ bne Arg
+ .endmacro
+
+ .macro bze Arg
+ beq Arg
+ .endmacro
+
</verb></tscreen>
CPU_65SC02
CPU_65C02
CPU_65816
- CPU_SUNPLUS
CPU_SWEET16
CPU_HUC6280
</verb></tscreen>
CPU_ISET_65SC02
CPU_ISET_65C02
CPU_ISET_65816
- CPU_ISET_SUNPLUS
CPU_ISET_SWEET16
CPU_ISET_HUC6280
</verb></tscreen>
compiler, depending on the target system selected:
<itemize>
-<item><tt/__APPLE2__/ - Target system is <tt/apple2/
+<item><tt/__APPLE2__/ - Target system is <tt/apple2/ or <tt/apple2enh/
<item><tt/__APPLE2ENH__/ - Target system is <tt/apple2enh/
-<item><tt/__ATARI__/ - Target system is <tt/atari/
+<item><tt/__ATARI__/ - Target system is <tt/atari/ or <tt/atarixl/
+<item><tt/__ATARIXL__/ - Target system is <tt/atarixl/
<item><tt/__ATMOS__/ - Target system is <tt/atmos/
<item><tt/__BBC__/ - Target system is <tt/bbc/
<item><tt/__C128__/ - Target system is <tt/c128/
-<item><tt/__C16__/ - Target system is <tt/c16/
+<item><tt/__C16__/ - Target system is <tt/c16/ or <tt/plus4/
<item><tt/__C64__/ - Target system is <tt/c64/
<item><tt/__CBM__/ - Target is a Commodore system
<item><tt/__CBM510__/ - Target system is <tt/cbm510/
<item><tt/__CBM610__/ - Target system is <tt/cbm610/
-<item><tt/__GEOS__/ - Target system is <tt/geos/
+<item><tt/__GEOS__/ - Target is a GEOS system
+<item><tt/__GEOS_APPLE__/ - Target system is <tt/geos-apple/
+<item><tt/__GEOS_CBM__/ - Target system is <tt/geos-cbm/
<item><tt/__LUNIX__/ - Target system is <tt/lunix/
+<item><tt/__LYNX__/ - Target system is <tt/lynx/
<item><tt/__NES__/ - Target system is <tt/nes/
<item><tt/__PET__/ - Target system is <tt/pet/
<item><tt/__PLUS4__/ - Target system is <tt/plus4/
+<item><tt/__SIM6502__/ - Target system is <tt/sim6502/
+<item><tt/__SIM65C02__/ - Target system is <tt/sim65c02/
<item><tt/__SUPERVISION__/ - Target system is <tt/supervision/
<item><tt/__VIC20__/ - Target system is <tt/vic20/
</itemize>
</verb></tscreen>
A union shares the total space between all its members, its size is the same
-as that of the largest member.
+as that of the largest member. The offset of all members relative to the union
+is zero.
+
+<tscreen><verb>
+ .union Entry
+ index .word
+ ptr .addr
+ .endunion
+</verb></tscreen>
A struct or union must not necessarily have a name. If it is anonymous, no
local scope is opened, the identifiers used to name the members are placed
Using the <tt><ref id=".CONSTRUCTOR" name=".CONSTRUCTOR"></tt>, <tt><ref
id=".DESTRUCTOR" name=".DESTRUCTOR"></tt> and <tt><ref id=".INTERRUPTOR"
-name=".INTERRUPTOR"></tt> keywords it it possible to export functions in a
+name=".INTERRUPTOR"></tt> keywords it is possible to export functions in a
special way. The linker is able to generate tables with all functions of a
specific type. Such a table will <em>only</em> include symbols from object
files that are linked into a specific executable. This may be used to add
</enum>
-<sect>Bugs/Feedback<p>
-
-If you have problems using the assembler, if you find any bugs, or if
-you're doing something interesting with the assembler, I would be glad to
-hear from you. Feel free to contact me by email
-(<htmlurl url="mailto:uz@cc65.org" name="uz@cc65.org">).
-
-
-
<sect>Copyright<p>
ca65 (and all cc65 binutils) are (C) Copyright 1998-2003 Ullrich von
projects / cc65 / blobdiff