-<!doctype linuxdoc system>
+<!doctype linuxdoc system> <!-- -*- text-mode -*- -->
<article>
<title>ca65 Users Guide
-<author>Ullrich von Bassewitz, <htmlurl url="mailto:uz@cc65.org" name="uz@cc65.org">
-<date>19.07.2000, 29.11.2000, 02.10.2001
+<author><url url="mailto:uz@cc65.org" name="Ullrich von Bassewitz">
+<date>2014-04-24
<abstract>
ca65 is a powerful macro assembler for the 6502, 65C02 and 65816 CPUs. It is
---------------------------------------------------------------------------
Usage: ca65 [options] file
Short options:
- -D name[=value] Define a symbol
- -I dir Set an include directory search path
- -U Mark unresolved symbols as import
- -V Print the assembler version
- -W n Set warning level n
- -g Add debug info to object file
- -h Help (this text)
- -i Ignore case of symbols
- -l Create a listing if assembly was ok
- -mm model Set the memory model
- -o name Name the output file
- -s Enable smart mode
- -t sys Set the target system
- -v Increase verbosity
+ -D name[=value] Define a symbol
+ -I dir Set an include directory search path
+ -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
+ -l name Create a listing file if assembly was ok
+ -mm model Set the memory model
+ -o name Name the output file
+ -s Enable smart mode
+ -t sys Set the target system
+ -v Increase verbosity
Long options:
- --auto-import Mark unresolved symbols as import
- --cpu type Set cpu type
- --debug-info Add debug info to object file
- --feature name Set an emulation feature
- --help Help (this text)
- --ignore-case Ignore case of symbols
- --include-dir dir Set an include directory search path
- --listing Create a listing 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
- --smart Enable smart mode
- --target sys Set the target system
- --verbose Increase verbosity
- --version Print the assembler version
+ --auto-import Mark unresolved symbols as import
+ --bin-include-dir dir Set a search path for binary includes
+ --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
+ --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
+ --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
+ --version Print the assembler version
---------------------------------------------------------------------------
</verb></tscreen>
<descrip>
+ <label id="option--bin-include-dir">
+ <tag><tt>--bin-include-dir dir</tt></tag>
+
+ Name a directory which is searched for binary include files. The option
+ may be used more than once to specify more than one directory to search. The
+ current directory is always searched first before considering any
+ additional directories. See also the section about <ref id="search-paths"
+ name="search paths">.
+
+
<label id="option--cpu">
<tag><tt>--cpu type</tt></tag>
Set the default for the CPU type. The option takes a parameter, which
may be one of
- 6502, 65SC02, 65C02, 65816, sunplus, sweet16, HuC6280
+ 6502, 65SC02, 65C02, 65816, sweet16, HuC6280
+
+
+ <label id="option-create-dep">
+ <tag><tt>--create-dep name</tt></tag>
+
+ Tells the assembler to generate a file containing the dependency list for
+ the assembled module in makefile syntax. The output is written to a file
+ with the given name. The output does not include files passed via debug
+ information to the assembler.
+
+
+ <label id="option-create-full-dep">
+ <tag><tt>--create-full-dep name</tt></tag>
+
+ Tells the assembler to generate a file containing the dependency list for
+ the assembled module in makefile syntax. The output is written to a file
+ with the given name. The output does include files passed via debug
+ information to the assembler.
+
- The sunplus cpu is not available in the freeware version, because the
- instruction set is "proprietary and confidential".
+ <tag><tt>-d, --debug</tt></tag>
+
+ Enables debug mode, something that should not be needed for mere
+ mortals:-)
<label id="option--feature">
monitor.
+ <label id="option-h">
<tag><tt>-h, --help</tt></tag>
Print the short option summary shown above.
+ <label id="option-i">
<tag><tt>-i, --ignore-case</tt></tag>
This option makes the assembler case insensitive on identifiers and labels.
<tt><ref id=".CASE" name=".CASE"></tt> control command.
- <tag><tt>-l, --listing</tt></tag>
+ <label id="option-l">
+ <tag><tt>-l name, --listing name</tt></tag>
+
+ Generate an assembler listing with the given name. A listing file will
+ never be generated in case of assembly errors.
+
- Generate an assembler listing. The listing file will always have the
- name of the main input file with the extension replaced by ".lst". This
- may change in future versions.
+ <label id="option--large-alignment">
+ <tag><tt>--large-alignment</tt></tag>
+ Disable warnings about a large combined alignment. See the discussion of the
+ <tt><ref id=".ALIGN" name=".ALIGN"></tt> directive for futher information.
+
+ <label id="option--list-bytes">
<tag><tt>--list-bytes n</tt></tag>
Set the maximum number of bytes printed in the listing for one line of
number of printed bytes.
- <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>
Define the default memory model. Possible model specifiers are near, far and
huge.
+ <label id="option-o">
<tag><tt>-o name</tt></tag>
The default output name is the name of the input file with the extension
the source file, or, if -o is given, the full path in this name is used.
+ <label id="option--pagelength">
<tag><tt>--pagelength n</tt></tag>
sets the length of a listing page in lines. See the <tt><ref
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>
In smart mode (enabled by -s or the <tt><ref id=".SMART" name=".SMART"></tt>
<label id="option-t">
<tag><tt>-t sys, --target sys</tt></tag>
- Set the target system. This will enable translation of character strings
- and character constants into the character set of the target platform.
- The default for the target system is "none", which means that no translation
+ Set the target system. This will enable translation of character strings and
+ character constants into the character set of the target platform. The
+ default for the target system is "none", which means that no translation
will take place. The assembler supports the same target systems as the
compiler, see there for a list.
+ Depending on the target, the default CPU type is also set. This can be
+ overriden by using the <tt/<ref id="option--cpu" name="--cpu">/ option.
+
+ <label id="option-v">
<tag><tt>-v, --verbose</tt></tag>
Increase the assembler verbosity. Usually only needed for debugging
verbose output.
+ <label id="option-D">
<tag><tt>-D</tt></tag>
This option allows you to define symbols on the command line. Without a
you may have to quote the expression.
+ <label id="option-I">
<tag><tt>-I dir, --include-dir dir</tt></tag>
Name a directory which is searched for include files. The option may be
used more than once to specify more than one directory to search. The
current directory is always searched first before considering any
- additional directories.
+ additional directories. See also the section about <ref id="search-paths"
+ name="search paths">.
+ <label id="option-U">
<tag><tt>-U, --auto-import</tt></tag>
Mark symbols that are not defined in the sources as imported symbols. This
which is not always true for assembler programmers.
+ <label id="option-V">
<tag><tt>-V, --version</tt></tag>
Print the version number of the assembler. If you send any suggestions
<p>
+
+<sect>Search paths<label id="search-paths"><p>
+
+Normal include files are searched in the following places:
+
+<enum>
+<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>An optionally compiled-in directory.
+</enum>
+
+Binary include files are searched in the following places:
+
+<enum>
+<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>
+
+
+
<sect>Input format<p>
<sect1>Assembler syntax<p>
<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>
DEA is an alias for DEC A
INA is an alias for INC A
SWA is an alias for XBA
- TAD is an alias for TCD
+ TAD is an alias for TCD
TAS is an alias for TCS
TDA is an alias for TDC
TSA is an alias for TSC
6502X mode is an extension to the normal 6502 mode. In this mode, several
mnemonics for illegal instructions of the NMOS 6502 CPUs are accepted. Since
these instructions are illegal, there are no official mnemonics for them. The
-unofficial ones are taken from <htmlurl
-url="http://oxyron.net/graham/opcodes02.html"
-name="http://oxyron.net/graham/opcodes02.html">. Please note that only the
+unofficial ones are taken from <url
+url="http://www.oxyron.de/html/opcodes02.html">. Please note that only the
ones marked as "stable" are supported. The following table uses information
from the mentioned web page, for more information, see there.
<itemize>
-<item><tt>ALR: A:=(A and #{imm})*2;</tt>
+<item><tt>ALR: A:=(A and #{imm})/2;</tt>
<item><tt>ANC: A:=A and #{imm};</tt> Generates opcode $0B.
<item><tt>ARR: A:=(A and #{imm})/2;</tt>
<item><tt>AXS: X:=A and X-#{imm};</tt>
][ programmers do probably know how to use sweet16 mode.
For more information about SWEET 16, see
-<htmlurl url="http://www.6502.org/source/interpreters/sweet16.htm"
-name="http://www.6502.org/source/interpreters/sweet16.htm">.
+<url url="http://www.6502.org/source/interpreters/sweet16.htm">.
<sect1>Number format<p>
<item> If the expression contains symbols that are not defined, and these
symbols are local symbols, the enclosing scopes are searched for a
symbol with the same name. If one exists and this symbol is defined,
- it's attributes are used to determine the result size.
+ its attributes are used to determine the result size.
<item> In all other cases the expression is assumed to be word sized.
</itemize>
<sect1>Available operators<label id="operators"><p>
-Available operators sorted by precedence:
-
<table>
-<tabular ca="llc">
-Op|Description|Precedence@<hline>
- |Builtin string functions|0@
- |Builtin pseudo variables|1@
- |Builtin pseudo functions|1@
-+|Unary plus|1@
--|Unary minus|1@
-˜|Unary bitwise not|1@
-.BITNOT|Unary bitwise not|1@
-<|Low byte operator|1@
->|High byte operator|1@
-^|Bank byte operator|1@
-*|Multiplication|2@
-/|Division|2@
-.MOD|Modulo operation|2@
-&|Bitwise and|2@
-.BITAND|Bitwise and|2@
-^|Bitwise xor|2@
-.BITXOR|Bitwise xor|2@
-<<|Shift left operator|2@
-.SHL|Shift left operator|2@
->>|Shift right operato|r@
-.SHR|Shift right operator|2@
-+|Binary plus|3@
--|Binary minus|3@
-||Binary or|3@
-.BITOR|Binary or|3@
-=|Compare operation (equal)|4@
-<>|Compare operation (not equal)|4@
-<|Compare operation (less)|4@
->|Compare operation (greater)|4@
-<=|Compare operation (less or equal)|4@
->=|Compare operation (greater or equal)|4@
-&&|Boolean and|5@
-.AND|Boolean and|5@
-.XOR|Boolean xor|5@
-|||Boolean or|6@
-.OR|Boolean or|6@
-!|Boolean not|7@
-.NOT|Boolean not|7@
+<tabular ca="clc">
+<bf/Operator/| <bf/Description/| <bf/Precedence/@<hline>
+| Built-in string functions| 0@
+||~@
+| Built-in pseudo-variables| 1@
+| Built-in pseudo-functions| 1@
++| Unary positive| 1@
+-| Unary negative| 1@
+˜<newline>
+.BITNOT| Unary bitwise not| 1@
+<<newline>
+.LOBYTE| Unary low-byte operator| 1@
+><newline>
+.HIBYTE| Unary high-byte operator| 1@
+^<newline>
+.BANKBYTE| Unary bank-byte operator| 1@
+||~@
+*| Multiplication| 2@
+/| Division| 2@
+.MOD| Modulo operator| 2@
+&<newline>
+.BITAND| Bitwise and| 2@
+^<newline>
+.BITXOR| Binary bitwise xor| 2@
+<<<newline>
+.SHL| Shift-left operator| 2@
+>><newline>
+.SHR| Shift-right operator| 2@
+||~@
++| Binary addition| 3@
+-| Binary subtraction| 3@
+|<newline>
+.BITOR| Bitwise or| 3@
+||~@
+= | Compare operator (equal)| 4@
+<>| Compare operator (not equal)| 4@
+<| Compare operator (less)| 4@
+>| Compare operator (greater)| 4@
+<=| Compare operator (less or equal)| 4@
+>=| Compare operator (greater or equal)| 4@
+||~@
+&&<newline>
+.AND| Boolean and| 5@
+.XOR| Boolean xor| 5@
+||~@
+||<newline>
+.OR| Boolean or| 6@
+||~@
+!<newline>
+.NOT| Boolean not| 7@<hline>
</tabular>
-<caption>Available operators sorted by precedence
+<caption>Available operators, sorted by precedence
</table>
-To force a specific order of evaluation, braces may be used as usual.
-<p>
+To force a specific order of evaluation, parentheses may be used, as usual.
<sect>Symbols and labels<p>
+A symbol or label is an identifier that starts with a letter and is followed
+by letters and digits. Depending on some features enabled (see
+<tt><ref id="at_in_identifiers" name="at_in_identifiers"></tt>,
+<tt><ref id="dollar_in_identifiers" name="dollar_in_identifiers"></tt> and
+<tt><ref id="leading_dot_in_identifiers" name="leading_dot_in_identifiers"></tt>)
+other characters may be present. Use of identifiers consisting of a single
+character will not work in all cases, because some of these identifiers are
+reserved keywords (for example "A" is not a valid identifier for a label,
+because it is the keyword for the accumulator).
+
The assembler allows you to use symbols instead of naked values to make
the source more readable. There are a lot of different ways to define and
use symbols and labels, giving a lot of flexibility.
-
<sect1>Numeric constants<p>
Numeric constants are defined using the equal sign or the label assignment
operator. After doing
<tscreen><verb>
- two = 2
+ two = 2
</verb></tscreen>
may use the symbol "two" in every place where a number is expected, and it is
-evaluated to the value 2 in this context. The label assignment operator causes
-the same, but causes the symbol to be marked as a label, which may cause a
-different handling in the debugger:
+evaluated to the value 2 in this context. The label assignment operator is
+almost identical, but causes the symbol to be marked as a label, so it may be
+handled differently in a debugger:
<tscreen><verb>
- io := $d000
+ io := $d000
</verb></tscreen>
The right side can of course be an expression:
<tscreen><verb>
- four = two * two
+ four = two * two
+</verb></tscreen>
+
+
+<label id="variables">
+<sect1>Numeric variables<p>
+
+Within macros and other control structures (<tt><ref id=".REPEAT"
+name=".REPEAT"></tt>, ...) it is sometimes useful to have some sort of
+variable. This can be achieved by the <tt>.SET</tt> operator. It creates a
+symbol that may get assigned a different value later:
+
+<tscreen><verb>
+ four .set 4
+ lda #four ; Loads 4 into A
+ four .set 3
+ lda #four ; Loads 3 into A
+</verb></tscreen>
+
+Since the value of the symbol can change later, it must be possible to
+evaluate it when used (no delayed evaluation as with normal symbols). So the
+expression used as the value must be constant.
+
+Following is an example for a macro that generates a different label each time
+it is used. It uses the <tt><ref id=".SPRINTF" name=".SPRINTF"></tt> function
+and a numeric variable named <tt>lcount</tt>.
+
+<tscreen><verb>
+ .lcount .set 0 ; Initialize the counter
+
+ .macro genlab
+ .ident (.sprintf ("L%04X", lcount)):
+ lcount .set lcount + 1
+ .endmacro
</verb></tscreen>
names like "Loop". Here is an example:
<tscreen><verb>
- Clear: lda #$00 ; Global label
- ldy #$20
- @Loop: sta Mem,y ; Local label
- dey
- bne @Loop ; Ok
- rts
+ Clear: lda #$00 ; Global label
+ ldy #$20
+ @Loop: sta Mem,y ; Local label
+ dey
+ bne @Loop ; Ok
+ rts
Sub: ... ; New global label
- bne @Loop ; ERROR: Unknown identifier!
+ bne @Loop ; ERROR: Unknown identifier!
</verb></tscreen>
<sect1>Unnamed labels<p>
understand this:
<tscreen><verb>
- : lda (ptr1),y ; #1
- cmp (ptr2),y
- bne :+ ; -> #2
- tax
- beq :+++ ; -> #4
- iny
- bne :- ; -> #1
- inc ptr1+1
- inc ptr2+1
- bne :- ; -> #1
-
- : bcs :+ ; #2 -> #3
- ldx #$FF
- rts
-
- : ldx #$01 ; #3
- : rts ; #4
+ : lda (ptr1),y ; #1
+ cmp (ptr2),y
+ bne :+ ; -> #2
+ tax
+ beq :+++ ; -> #4
+ iny
+ bne :- ; -> #1
+ inc ptr1+1
+ inc ptr2+1
+ bne :- ; -> #1
+
+ : bcs :+ ; #2 -> #3
+ ldx #$FF
+ rts
+
+ : ldx #$01 ; #3
+ : rts ; #4
</verb></tscreen>
As you can see from the example, unnamed labels will make even short
prefer the "cheap" local labels). Nevertheless, unnamed labels are
convenient in some situations, so it's your decision.
+<em/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>
- .DEFINE two 2
- .DEFINE version "SOS V2.3"
+ .DEFINE two 2
+ .DEFINE version "SOS V2.3"
- four = two * two ; Ok
- .byte version ; Ok
+ four = two * two ; Ok
+ .byte version ; Ok
- .PROC ; Start local scope
- two = 3 ; Will give "2 = 3" - invalid!
- .ENDPROC
+ .PROC ; Start local scope
+ two = 3 ; Will give "2 = 3" - invalid!
+ .ENDPROC
</verb></tscreen>
<tscreen><verb>
.proc foo
...
- .endscope
+ .endproc
</verb></tscreen>
is actually the same as
This is the reason why a procedure must have a name. If you want a scope
without a name, use <tt/<ref id=".SCOPE" name=".SCOPE">/.
-<bf/Note:/ As you can see from the example above, scopes and symbols live in
+<em/Note:/ As you can see from the example above, scopes and symbols live in
different namespaces. There can be a symbol named <tt/foo/ and a scope named
<tt/foo/ without any conflicts (but see the section titled <ref
id="scopesearch" name=""Scope search order"">).
Reading this pseudo variable will give the assembler version according to
the following formula:
- VER_MAJOR*$100 + VER_MINOR*$10 + VER_PATCH
+ VER_MAJOR*$100 + VER_MINOR*$10
It may be used to encode the assembler version or check the assembler for
special features not available with older versions.
Example:
- Version 2.11.1 of the assembler will return $2B1 as numerical constant when
+ Version 2.14 of the assembler will return $2E0 as numerical constant when
reading the pseudo variable <tt/.VERSION/.
either a string or an expression.
+<sect1><tt>.BANK</tt><label id=".BANK"><p>
+
+ The <tt/.BANK/ function is used to support systems with banked memory. The
+ argument is an expression with exactly one segment reference - usually a
+ label. The function result is the value of the <tt/bank/ attribute assigned
+ to the run memory area of the segment. Please see the linker documentation
+ for more information about memory areas and their attributes.
+
+ The value of <tt/.BANK/ can be used to switch memory so that a memory bank
+ containing specific data is available.
+
+ The <tt/bank/ attribute is a 32 bit integer and so is the result of the
+ <tt/.BANK/ function. You will have to use <tt><ref id=".LOBYTE"
+ name=".LOBYTE"></tt> or similar functions to address just part of it.
+
+ Please note that <tt/.BANK/ will always get evaluated in the link stage, so
+ an expression containing <tt/.BANK/ can never be used where a constant known
+ result is expected (for example with <tt/.RES/).
+
+ Example:
+
+ <tscreen><verb>
+ .segment "BANK1"
+ .proc banked_func_1
+ ...
+ .endproc
+
+ .segment "BANK2"
+ .proc banked_func_2
+ ...
+ .endproc
+
+ .proc bank_table
+ .addr banked_func_1
+ .byte <.BANK (banked_func_1)
+
+ .addr banked_func_2
+ .byte <.BANK (banked_func_2)
+ .endproc
+ </verb></tscreen>
+
+
+
<sect1><tt>.BANKBYTE</tt><label id=".BANKBYTE"><p>
The function returns the bank byte (that is, bits 16-23) of its argument.
See: <tt><ref id=".XMATCH" name=".XMATCH"></tt>
+<sect1><tt>.MAX</tt><label id=".MAX"><p>
+
+ Builtin function. The result is the larger of two values.
+
+ The syntax is
+
+ <tscreen><verb>
+ .MAX (<value #1>, <value #2>)
+ </verb></tscreen>
+
+ Example:
+
+ <tscreen><verb>
+ ; Reserve space for the larger of two data blocks
+ savearea: .max (.sizeof (foo), .sizeof (bar))
+ </verb></tscreen>
+
+ See: <tt><ref id=".MIN" name=".MIN"></tt>
+
+
<sect1><tt>.MID</tt><label id=".MID"><p>
Builtin function. Takes a starting index, a count and a token list as
name=".RIGHT"></tt> builtin functions.
+<sect1><tt>.MIN</tt><label id=".MIN"><p>
+
+ Builtin function. The result is the smaller of two values.
+
+ The syntax is
+
+ <tscreen><verb>
+ .MIN (<value #1>, <value #2>)
+ </verb></tscreen>
+
+ Example:
+
+ <tscreen><verb>
+ ; Reserve space for some data, but 256 bytes minimum
+ savearea: .min (.sizeof (foo), 256)
+ </verb></tscreen>
+
+ See: <tt><ref id=".MAX" name=".MAX"></tt>
+
+
<sect1><tt>.REF, .REFERENCED</tt><label id=".REFERENCED"><p>
Builtin function. The function expects an identifier as argument in braces.
<tscreen><verb>
.struct Point ; Struct size = 4
xcoord .word
- xcoord .word
+ ycoord .word
.endstruct
P: .tag Point ; Declare a point
<sect1><tt>.ALIGN</tt><label id=".ALIGN"><p>
Align data to a given boundary. The command expects a constant integer
- argument that must be a power of two, plus an optional second argument
+ argument in the range 1 ... 65536, plus an optional second argument
in byte range. If there is a second argument, it is used as fill value,
otherwise the value defined in the linker configuration file is used
(the default for this value is zero).
- Since alignment depends on the base address of the module, you must
- give the same (or a greater) alignment for the segment when linking.
- The linker will give you a warning, if you don't do that.
+ <tt/.ALIGN/ will insert fill bytes, and the number of fill bytes depend of
+ the final address of the segment. <tt/.ALIGN/ cannot insert a variable
+ number of bytes, since that would break address calculations within the
+ module. So each <tt/.ALIGN/ expects the segment to be aligned to a multiple
+ of the alignment, because that allows the number of fill bytes to be
+ calculated in advance by the assembler. You are therefore required to
+ specify a matching alignment for the segment in the linker config. The
+ linker will output a warning if the alignment of the segment is less than
+ what is necessary to have a correct alignment in the object file.
Example:
.align 256
</verb></tscreen>
+ Some unexpected behaviour might occur if there are multiple <tt/.ALIGN/
+ commands with different arguments. To allow the assembler to calculate the
+ number of fill bytes in advance, the alignment of the segment must be a
+ multiple of each of the alignment factors. This may result in unexpectedly
+ large alignments for the segment within the module.
+
+ Example:
+
+ <tscreen><verb>
+ .align 15
+ .byte 15
+ .align 18
+ .byte 18
+ </verb></tscreen>
+
+ For the assembler to be able to align correctly, the segment must be aligned
+ to the least common multiple of 15 and 18 which is 90. The assembler will
+ calculate this automatically and will mark the segment with this value.
+
+ Unfortunately, the combined alignment may get rather large without the user
+ knowing about it, wasting space in the final executable. If we add another
+ alignment to the example above
+
+ <tscreen><verb>
+ .align 15
+ .byte 15
+ .align 18
+ .byte 18
+ .align 251
+ .byte 0
+ </verb></tscreen>
+
+ the assembler will force a segment alignment to the least common multiple of
+ 15, 18 and 251 - which is 22590. To protect the user against errors, the
+ assembler will issue a warning when the combined alignment exceeds 256. The
+ command line option <tt><ref id="option--large-alignment"
+ name="--large-alignment"></tt> will disable this warning.
+
+ Please note that with alignments that are a power of two (which were the
+ only alignments possible in older versions of the assembler), the problem is
+ less severe, because the least common multiple of powers to the same base is
+ always the larger one.
+
+
<sect1><tt>.ASCIIZ</tt><label id=".ASCIIZ"><p>
Add an assertion. The command is followed by an expression, an action
specifier, and an optional message that is output in case the assertion
fails. If no message was given, the string "Assertion failed" is used. The
- action specifier may be one of <tt/warning/ or <tt/error/. The assertion is
- evaluated by the assembler if possible, and also passed to the linker in the
- object file (if one is generated). The linker will then evaluate the
+ action specifier may be one of <tt/warning/, <tt/error/, <tt/ldwarning/ or
+ <tt/lderror/. In the former two cases, the assertion is evaluated by the
+ assembler if possible, and in any case, it's also passed to the linker in
+ the object file (if one is generated). The linker will then evaluate the
expression when segment placement has been done.
Example:
when the output file is written, and abort with an error if this is not
the case. More complex expressions are possible. The action specifier
<tt/warning/ outputs a warning, while the <tt/error/ specifier outputs
- an error message. In the latter case, generation if the output file is
+ an error message. In the latter case, generation of the output file is
suppressed in both the assembler and linker.
.autoimport + ; Switch on auto import
</verb></tscreen>
+<sect1><tt>.BANKBYTES</tt><label id=".BANKBYTES"><p>
+
+ Define byte sized data by extracting only the bank byte (that is, bits 16-23) from
+ each expression. This is equivalent to <tt><ref id=".BYTE" name=".BYTE"></tt> with
+ the operator '^' prepended to each expression in its list.
+
+ Example:
+
+ <tscreen><verb>
+ .define MyTable TableItem0, TableItem1, TableItem2, TableItem3
+
+ TableLookupLo: .lobytes MyTable
+ TableLookupHi: .hibytes MyTable
+ TableLookupBank: .bankbytes MyTable
+ </verb></tscreen>
+
+ which is equivalent to
+
+ <tscreen><verb>
+ TableLookupLo: .byte <TableItem0, <TableItem1, <TableItem2, <TableItem3
+ TableLookupHi: .byte >TableItem0, >TableItem1, >TableItem2, >TableItem3
+ TableLookupBank: .byte ^TableItem0, ^TableItem1, ^TableItem2, ^TableItem3
+ </verb></tscreen>
+
+ See also: <tt><ref id=".BYTE" name=".BYTE"></tt>,
+ <tt><ref id=".HIBYTES" name=".HIBYTES"></tt>,
+ <tt><ref id=".LOBYTES" name=".LOBYTES"></tt>
+
<sect1><tt>.BSS</tt><label id=".BSS"><p>
<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.
- See section <ref id="macros" name="Macros">.
+
+ 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">.
+
+
+<sect1><tt>.DELMAC, .DELMACRO</tt><label id=".DELMACRO"><p>
+
+ Delete a classic macro (defined with <tt><ref id=".MACRO"
+ name=".MACRO"></tt>) . The command is followed by the name of an
+ existing macro. Its definition will be deleted together with the name.
+ If necessary, another macro with this name may be defined later.
+
+ See: <tt><ref id=".ENDMACRO" name=".ENDMACRO"></tt>,
+ <tt><ref id=".EXITMACRO" name=".EXITMACRO"></tt>,
+ <tt><ref id=".MACRO" name=".MACRO"></tt>
+
+ See also section <ref id="macros" name="Macros">.
<sect1><tt>.DEF, .DEFINED</tt><label id=".DEFINED"><p>
<tt><ref id=".IFDEF" name=".IFDEF"></tt> statement may be replaced by
<tscreen><verb>
- .if .defined(a)
+ .if .defined(a)
</verb></tscreen>
<sect1><tt>.ENDMAC, .ENDMACRO</tt><label id=".ENDMACRO"><p>
- End of macro definition (see section <ref id="macros" name="Macros">).
+ Marks the end of a macro definition.
+
+ See: <tt><ref id=".DELMACRO" name=".DELMACRO"></tt>,
+ <tt><ref id=".EXITMACRO" name=".EXITMACRO"></tt>,
+ <tt><ref id=".MACRO" name=".MACRO"></tt>
+
+ See also section <ref id="macros" name="Macros">.
<sect1><tt>.ENDPROC</tt><label id=".ENDPROC"><p>
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/
<sect1><tt>.ERROR</tt><label id=".ERROR"><p>
Force an assembly error. The assembler will output an error message
- preceded by "User error" and will <em/not/ produce an object file.
+ preceded by "User error". Assembly is continued but no object file will
+ generated.
This command may be used to check for initial conditions that must be
set before assembling a source file.
.endif
</verb></tscreen>
- See also the <tt><ref id=".WARNING" name=".WARNING"></tt> and <tt><ref
- id=".OUT" name=".OUT"></tt> directives.
+ See also: <tt><ref id=".FATAL" name=".FATAL"></tt>,
+ <tt><ref id=".OUT" name=".OUT"></tt>,
+ <tt><ref id=".WARNING" name=".WARNING"></tt>
<sect1><tt>.EXITMAC, .EXITMACRO</tt><label id=".EXITMACRO"><p>
Abort a macro expansion immediately. This command is often useful in
- recursive macros. See separate section <ref id="macros" name="Macros">.
+ recursive macros.
+
+ See: <tt><ref id=".DELMACRO" name=".DELMACRO"></tt>,
+ <tt><ref id=".ENDMACRO" name=".ENDMACRO"></tt>,
+ <tt><ref id=".MACRO" name=".MACRO"></tt>
+
+ See also section <ref id="macros" name="Macros">.
<sect1><tt>.EXPORT</tt><label id=".EXPORT"><p>
Make symbols accessible from other modules. Must be followed by a comma
- separated list of symbols to export, with each one optionally followed by
- an address specification. The default is to export the symbol with the
- address size it actually has. The assembler will issue a warning, if the
- symbol is exported with an address size smaller than the actual address
- size.
+ separated list of symbols to export, with each one optionally followed by an
+ address specification and (also optional) an assignment. Using an additional
+ assignment in the export statement allows to define and export a symbol in
+ one statement. The default is to export the symbol with the address size it
+ actually has. The assembler will issue a warning, if the symbol is exported
+ with an address size smaller than the actual address size.
- Example:
+ Examples:
<tscreen><verb>
.export foo
.export bar: far
+ .export foobar: far = foo * bar
+ .export baz := foobar, zap: far = baz - bar
</verb></tscreen>
+ As with constant definitions, using <tt/:=/ instead of <tt/=/ marks the
+ symbols as a label.
+
See: <tt><ref id=".EXPORTZP" name=".EXPORTZP"></tt>
Make symbols accessible from other modules. Must be followed by a comma
separated list of symbols to export. The exported symbols are explicitly
- marked as zero page symbols.
+ marked as zero page symbols. An assignment may be included in the
+ <tt/.EXPORTZP/ statement. This allows to define and export a symbol in one
+ statement.
- Example:
+ Examples:
<tscreen><verb>
.exportzp foo, bar
+ .exportzp baz := $02
</verb></tscreen>
See: <tt><ref id=".EXPORT" name=".EXPORT"></tt>
See: <tt><ref id=".ADDR" name=".ADDR"></tt>
+<sect1><tt>.FATAL</tt><label id=".FATAL"><p>
+
+ Force an assembly error and terminate assembly. The assembler will output an
+ error message preceded by "User error" and will terminate assembly
+ immediately.
+
+ This command may be used to check for initial conditions that must be
+ set before assembling a source file.
+
+ Example:
+
+ <tscreen><verb>
+ .if foo = 1
+ ...
+ .elseif bar = 1
+ ...
+ .else
+ .fatal "Must define foo or bar!"
+ .endif
+ </verb></tscreen>
+
+ See also: <tt><ref id=".ERROR" name=".ERROR"></tt>,
+ <tt><ref id=".OUT" name=".OUT"></tt>,
+ <tt><ref id=".WARNING" name=".WARNING"></tt>
+
+
<sect1><tt>.FEATURE</tt><label id=".FEATURE"><p>
This directive may be used to enable one or more compatibility features
<descrip>
- <tag><tt>at_in_identifiers</tt></tag>
+ <tag><tt>at_in_identifiers</tt><label id="at_in_identifiers"></tag>
Accept the at character (`@') as a valid character in identifiers. The
at character is not allowed to start an identifier, even with this
feature enabled.
- <tag><tt>dollar_in_identifiers</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
+ pitfall when using C like comments: All statements must be terminated by
+ "end-of-line". Using C like comments, it is possible to hide the newline,
+ which results in error messages. See the following non working example:
+
+ <tscreen><verb>
+ lda #$00 /* This comment hides the newline
+*/ sta $82
+ </verb></tscreen>
+
+ <tag><tt>dollar_in_identifiers</tt><label id="dollar_in_identifiers"></tag>
Accept the dollar sign (`$') as a valid character in identifiers. The
- at character is not allowed to start an identifier, even with this
+ 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).
- <tag><tt>leading_dot_in_identifiers</tt></tag>
+ <tag><tt>leading_dot_in_identifiers</tt><label id="leading_dot_in_identifiers"></tag>
Accept the dot (`.') as the first character of an identifier. This may be
used for example to create macro names that start with a dot emulating
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.
<tscreen><verb>
lda #'a
</verb></tscreen>
- <bf/Note:/ This does not work in conjunction with <tt/.FEATURE
+ <em/Note:/ This does not work in conjunction with <tt/.FEATURE
loose_string_term/, since in this case the input would be ambiguous.
- <tag><tt>pc_assignment</tt></tag>
+ <tag><tt>org_per_seg</tt><label id="org_per_seg"></tag>
+
+ This feature makes relocatable/absolute mode local to the current segment.
+ Using <tt><ref id=".ORG" name=".ORG"></tt> when <tt/org_per_seg/ is in
+ effect will only enable absolute mode for the current segment. Dito for
+ <tt><ref id=".RELOC" name=".RELOC"></tt>.
+
+ <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
.globalzp foo, bar
</verb></tscreen>
+<sect1><tt>.HIBYTES</tt><label id=".HIBYTES"><p>
+
+ Define byte sized data by extracting only the high byte (that is, bits 8-15) from
+ each expression. This is equivalent to <tt><ref id=".BYTE" name=".BYTE"></tt> with
+ the operator '>' prepended to each expression in its list.
+
+ Example:
+
+ <tscreen><verb>
+ .lobytes $1234, $2345, $3456, $4567
+ .hibytes $fedc, $edcb, $dcba, $cba9
+ </verb></tscreen>
+
+ which is equivalent to
+
+ <tscreen><verb>
+ .byte $34, $45, $56, $67
+ .byte $fe, $ed, $dc, $cb
+ </verb></tscreen>
+
+ Example:
+
+ <tscreen><verb>
+ .define MyTable TableItem0, TableItem1, TableItem2, TableItem3
+
+ TableLookupLo: .lobytes MyTable
+ TableLookupHi: .hibytes MyTable
+ </verb></tscreen>
+
+ which is equivalent to
+
+ <tscreen><verb>
+ TableLookupLo: .byte <TableItem0, <TableItem1, <TableItem2, <TableItem3
+ TableLookupHi: .byte >TableItem0, >TableItem1, >TableItem2, >TableItem3
+ </verb></tscreen>
+
+ See also: <tt><ref id=".BYTE" name=".BYTE"></tt>,
+ <tt><ref id=".LOBYTES" name=".LOBYTES"></tt>,
+ <tt><ref id=".BANKBYTES" name=".BANKBYTES"></tt>
+
<sect1><tt>.I16</tt><label id=".I16"><p>
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:
</verb></tscreen>
+<sect1><tt>.LOBYTES</tt><label id=".LOBYTES"><p>
+
+ Define byte sized data by extracting only the low byte (that is, bits 0-7) from
+ each expression. This is equivalent to <tt><ref id=".BYTE" name=".BYTE"></tt> with
+ the operator '<' prepended to each expression in its list.
+
+ Example:
+
+ <tscreen><verb>
+ .lobytes $1234, $2345, $3456, $4567
+ .hibytes $fedc, $edcb, $dcba, $cba9
+ </verb></tscreen>
+
+ which is equivalent to
+
+ <tscreen><verb>
+ .byte $34, $45, $56, $67
+ .byte $fe, $ed, $dc, $cb
+ </verb></tscreen>
+
+ Example:
+
+ <tscreen><verb>
+ .define MyTable TableItem0, TableItem1, TableItem2, TableItem3
+
+ TableLookupLo: .lobytes MyTable
+ TableLookupHi: .hibytes MyTable
+ </verb></tscreen>
+
+ which is equivalent to
+
+ <tscreen><verb>
+ TableLookupLo: .byte <TableItem0, <TableItem1, <TableItem2, <TableItem3
+ TableLookupHi: .byte >TableItem0, >TableItem1, >TableItem2, >TableItem3
+ </verb></tscreen>
+
+ See also: <tt><ref id=".BYTE" name=".BYTE"></tt>,
+ <tt><ref id=".HIBYTES" name=".HIBYTES"></tt>,
+ <tt><ref id=".BANKBYTES" name=".BANKBYTES"></tt>
+
+
<sect1><tt>.LOCAL</tt><label id=".LOCAL"><p>
This command may only be used inside a macro definition. It declares a
<tscreen><verb>
.macpack longbranch ; Include macro package
- cmp #$20 ; Set condition codes
- jne Label ; Jump long on condition
+ cmp #$20 ; Set condition codes
+ jne Label ; Jump long on condition
</verb></tscreen>
Macro packages are explained in more detail in section <ref
id="macropackages" name="Macro packages">.
-<sect1><tt>.MAC, .MACRO</tt><label id=".MAC"><p>
+<sect1><tt>.MAC, .MACRO</tt><label id=".MACRO"><p>
Start a classic macro definition. The command is followed by an identifier
(the macro name) and optionally by a comma separated list of identifiers
- that are macro parameters.
+ that are macro parameters. A macro definition is terminated by <tt><ref
+ id=".ENDMACRO" name=".ENDMACRO"></tt>.
- See section <ref id="macros" name="Macros">.
+ Example:
+
+ <tscreen><verb>
+ .macro ldax arg ; Define macro ldax
+ lda arg
+ ldx arg+1
+ </verb></tscreen>
+
+ See: <tt><ref id=".DELMACRO" name=".DELMACRO"></tt>,
+ <tt><ref id=".ENDMACRO" name=".ENDMACRO"></tt>,
+ <tt><ref id=".EXITMACRO" name=".EXITMACRO"></tt>
+
+ See also section <ref id="macros" name="Macros">.
<sect1><tt>.ORG</tt><label id=".ORG"><p>
assembled. Use <tt><ref id=".RELOC" name=".RELOC"></tt> to switch back to
relocatable code.
- Please note that you <em/do not need/ this command in most cases. Placing
+ By default, absolute/relocatable mode is global (valid even when switching
+ segments). Using <tt>.FEATURE <ref id="org_per_seg" name="org_per_seg"></tt>
+ it can be made segment local.
+
+ Please note that you <em/do not need/ <tt/.ORG/ in most cases. Placing
code at a specific address is the job of the linker, not the assembler, so
there is usually no reason to assemble code to a specific address.
- You may not switch segments while inside a section of absolute code.
-
Example:
<tscreen><verb>
.out "This code was written by the codebuster(tm)"
</verb></tscreen>
- See also the <tt><ref id=".WARNING" name=".WARNING"></tt> and <tt><ref
- id=".ERROR" name=".ERROR"></tt> directives.
+ See also: <tt><ref id=".ERROR" name=".ERROR"></tt>,
+ <tt><ref id=".FATAL" name=".FATAL"></tt>,
+ <tt><ref id=".WARNING" name=".WARNING"></tt>
<sect1><tt>.P02</tt><label id=".P02"><p>
name=".PSC02"></tt> and <tt><ref id=".P816" name=".P816"></tt>
+<sect1><tt>.POPCPU</tt><label id=".POPCPU"><p>
+
+ Pop the last CPU setting from the stack, and activate it.
+
+ This command will switch back to the CPU that was last pushed onto the CPU
+ stack using the <tt><ref id=".PUSHCPU" name=".PUSHCPU"></tt> command, and
+ remove this entry from the stack.
+
+ The assembler will print an error message if the CPU stack is empty when
+ this command is issued.
+
+ See: <tt><ref id=".CPU" name=".CPU"></tt>, <tt><ref id=".PUSHCPU"
+ name=".PUSHCPU"></tt>, <tt><ref id=".SETCPU" name=".SETCPU"></tt>
+
+
<sect1><tt>.POPSEG</tt><label id=".POPSEG"><p>
Pop the last pushed segment from the stack, and set it.
name=".PC02"></tt> and <tt><ref id=".P816" name=".P816"></tt>
+<sect1><tt>.PUSHCPU</tt><label id=".PUSHCPU"><p>
+
+ Push the currently active CPU onto a stack. The stack has a size of 8
+ entries.
+
+ <tt/.PUSHCPU/ allows together with <tt><ref id=".POPCPU"
+ name=".POPCPU"></tt> to switch to another CPU and to restore the old CPU
+ later, without knowledge of the current CPU setting.
+
+ The assembler will print an error message if the CPU stack is already full,
+ when this command is issued.
+
+ See: <tt><ref id=".CPU" name=".CPU"></tt>, <tt><ref id=".POPCPU"
+ name=".POPCPU"></tt>, <tt><ref id=".SETCPU" name=".SETCPU"></tt>
+
+
<sect1><tt>.PUSHSEG</tt><label id=".PUSHSEG"><p>
Push the currently active segment onto a stack. The entries on the stack
None = 0 ; No error
File = 1 ; File error
Parse = 2 ; Parse error
- .endproc ; Close lexical level
+ .endscope ; Close lexical level
...
lda #Error::File ; Use symbol from scope Error
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, 65816 and 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>
</verb></tscreen>
+<sect1><tt>.UNDEF, .UNDEFINE</tt><label id=".UNDEFINE"><p>
+
+ Delete a define style macro definition. The command is followed by an
+ identifier which specifies the name of the macro to delete. Macro
+ replacement is switched of when reading the token following the command
+ (otherwise the macro name would be replaced by its replacement list).
+
+ See also the <tt><ref id=".DEFINE" name=".DEFINE"></tt> command and
+ 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
<tscreen><verb>
.macro jne target
- .local L1
- .ifndef target
- .warning "Forward jump in jne, cannot optimize!"
- beq L1
- jmp target
+ .local L1
+ .ifndef target
+ .warning "Forward jump in jne, cannot optimize!"
+ beq L1
+ jmp target
L1:
.else
- ...
- .endif
+ ...
+ .endif
.endmacro
</verb></tscreen>
- See also the <tt><ref id=".ERROR" name=".ERROR"></tt> and <tt><ref id=".OUT"
- name=".OUT"></tt> directives.
+ See also: <tt><ref id=".ERROR" name=".ERROR"></tt>,
+ <tt><ref id=".FATAL" name=".FATAL"></tt>,
+ <tt><ref id=".OUT" name=".OUT"></tt>
<sect1><tt>.WORD</tt><label id=".WORD"><p>
<sect1>Macros without parameters<p>
-In it's simplest form, a macro does not have parameters. Here's an
+In its simplest form, a macro does not have parameters. Here's an
example:
<tscreen><verb>
.macro asr ; Arithmetic shift right
- cmp #$80 ; Put bit 7 into carry
- ror ; Rotate right with carry
- .endmacro
+ cmp #$80 ; Put bit 7 into carry
+ ror ; Rotate right with carry
+ .endmacro
</verb></tscreen>
The macro above consists of two real instructions, that are inserted into
by using the name, like this:
<tscreen><verb>
- lda $2010
- asr
- sta $2010
+ lda $2010
+ asr
+ sta $2010
</verb></tscreen>
When using macro parameters, macros can be even more useful:
<tscreen><verb>
- .macro inc16 addr
- clc
- lda addr
- adc #$01
- sta addr
- lda addr+1
- adc #$00
- sta addr+1
- .endmacro
+ .macro inc16 addr
+ clc
+ lda addr
+ adc #$01
+ sta addr
+ lda addr+1
+ adc #$00
+ sta addr+1
+ .endmacro
</verb></tscreen>
When calling the macro, you may give a parameter, and each occurrence of
parameter. So
<tscreen><verb>
- inc16 $1000
+ inc16 $1000
</verb></tscreen>
will be expanded to
<tscreen><verb>
- clc
- lda $1000
- adc #$01
- sta $1000
- lda $1000+1
- adc #$00
- sta $1000+1
+ clc
+ lda $1000
+ adc #$01
+ sta $1000
+ lda $1000+1
+ adc #$00
+ sta $1000+1
</verb></tscreen>
A macro may have more than one parameter, in this case, the parameters
Look at this example:
<tscreen><verb>
- .macro ldaxy a, x, y
- .ifnblank a
- lda #a
- .endif
- .ifnblank x
- ldx #x
- .endif
- .ifnblank y
- ldy #y
- .endif
- .endmacro
+ .macro ldaxy a, x, y
+ .ifnblank a
+ lda #a
+ .endif
+ .ifnblank x
+ ldx #x
+ .endif
+ .ifnblank y
+ ldy #y
+ .endif
+ .endmacro
</verb></tscreen>
This macro may be called as follows:
<tscreen><verb>
- ldaxy 1, 2, 3 ; Load all three registers
+ ldaxy 1, 2, 3 ; Load all three registers
ldaxy 1, , 3 ; Load only a and y
immediately:
<tscreen><verb>
- .macro push r1, r2, r3, r4, r5, r6, r7
- .ifblank r1
- ; First parameter is empty
- .exitmacro
- .else
- lda r1
- pha
- .endif
- push r2, r3, r4, r5, r6, r7
- .endmacro
+ .macro push r1, r2, r3, r4, r5, r6, r7
+ .ifblank r1
+ ; First parameter is empty
+ .exitmacro
+ .else
+ lda r1
+ pha
+ .endif
+ push r2, r3, r4, r5, r6, r7
+ .endmacro
</verb></tscreen>
When expanding this macro, the expansion will push all given parameters
until an empty one is encountered. The macro may be called like this:
<tscreen><verb>
- push $20, $21, $32 ; Push 3 ZP locations
- push $21 ; Push one ZP location
+ push $20, $21, $32 ; Push 3 ZP locations
+ push $21 ; Push one ZP location
</verb></tscreen>
.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>
be omitted.
<item> Since <tt><ref id=".DEFINE" name=".DEFINE"></tt> style macros may not
- contain end-of-line tokens, there are things that cannot be done. They
+ contain end-of-line tokens, there are things that cannot be done. They
may not contain several processor instructions for example. So, while
some things may be done with both macro types, each type has special
usages. The types complement each other.
don't like that, use classic macros instead:
<tscreen><verb>
- .macro message
+ .macro DEBUG message
.out message
.endmacro
</verb></tscreen>
be sure to take the translation into account.
+<sect1>Deleting macros<p>
+
+Macros can be deleted. This will not work if the macro that should be deleted
+is currently expanded as in the following non working example:
+
+<tscreen><verb>
+ .macro notworking
+ .delmacro notworking
+ .endmacro
+
+ notworking ; Will not work
+</verb></tscreen>
+
+The commands to delete classic and define style macros differ. Classic macros
+can be deleted by use of <tt><ref id=".DELMACRO" name=".DELMACRO"></tt>, while
+for <tt><ref id=".DEFINE" name=".DEFINE"></tt> style macros, <tt><ref
+id=".UNDEFINE" name=".UNDEFINE"></tt> must be used. Example:
+
+<tscreen><verb>
+ .define value 1
+ .macro mac
+ .byte 2
+ .endmacro
+
+ .byte value ; Emit one byte with value 1
+ mac ; Emit another byte with value 2
+
+ .undefine value
+ .delmacro mac
+
+ .byte value ; Error: Unknown identifier
+ mac ; Error: Missing ":"
+</verb></tscreen>
+
+A separate command for <tt>.DEFINE</tt> style macros was necessary, because
+the name of such a macro is replaced by its replacement list on a very low
+level. To get the actual name, macro replacement has to be switched off when
+reading the argument to <tt>.UNDEFINE</tt>. This does also mean that the
+argument to <tt>.UNDEFINE</tt> is not allowed to come from another
+<tt>.DEFINE</tt>. All this is not necessary for classic macros, so having two
+different commands increases flexibility.
<sect>Macro packages<label id="macropackages"><p>
<sect1><tt>.MACPACK generic</tt><p>
This macro package defines macros that are useful in almost any program.
-Currently, two macros are defined:
+Currently defined macros are:
<tscreen><verb>
.macro add Arg
clc
- adc Arg
- .endmacro
+ adc Arg
+ .endmacro
+
+ .macro sub Arg
+ sec
+ sbc Arg
+ .endmacro
+
+ .macro bge Arg
+ bcs Arg
+ .endmacro
+
+ .macro blt Arg
+ bcc Arg
+ .endmacro
+
+ .macro bgt Arg
+ .local L
+ beq L
+ bcs Arg
+ L:
+ .endmacro
+
+ .macro ble Arg
+ beq Arg
+ bcc Arg
+ .endmacro
+
+ .macro bnz Arg
+ bne Arg
+ .endmacro
+
+ .macro bze Arg
+ beq Arg
+ .endmacro
- .macro sub Arg
- sec
- sbc Arg
- .endmacro
</verb></tscreen>
scheme:
<tscreen><verb>
- .macro jeq Target
+ .macro jeq Target
.if .def(Target) .and ((*+2)-(Target) <= 127)
beq Target
.else
- bne *+5
- jmp Target
+ bne *+5
+ jmp Target
.endif
.endmacro
</verb></tscreen>
+<sect1><tt>.MACPACK atari</tt><p>
+
+The atari macro package will define a macro named <tt/scrcode/. It takes a
+string as argument and places this string into memory translated into screen
+codes.
+
+
<sect1><tt>.MACPACK cbm</tt><p>
The cbm macro package will define a macro named <tt/scrcode/. It takes a
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/__ACE__/ - Target system is <tt/ace/
-<item><tt/__APPLE2__",/ - Target system is <tt/apple2/
-<item><tt/__APPLE2ENH__",/ - Target system is <tt/apple2enh/
-<item><tt/__ATARI__/ - Target system is <tt/atari/
-<item><tt/__ATMOS__",/ - Target system is <tt/atmos/
-<item><tt/__BBC__",/ - Target system is <tt/bbc/
+<item><tt/__APPLE2__/ - Target system is <tt/apple2/ or <tt/apple2enh/
+<item><tt/__APPLE2ENH__/ - Target system is <tt/apple2enh/
+<item><tt/__ATARI5200__/ - Target system is <tt/atari5200/
+<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/__LUNIX__",/ - Target system is <tt/lunix/
-<item><tt/__NES__",/ - Target system is <tt/nes/
+<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/__SUPERVISION__",/ - Target system is <tt/supervision/
+<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>
<sect>Structs and unions<label id="structs"><p>
-<sect1>Overview<p>
+<sect1>Structs and unions Overview<p>
Structs and unions are special forms of <ref id="scopes" name="scopes">. They
are to some degree comparable to their C counterparts. Both have a list of
</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
useful for assembler programs.
-<sect1>Overview<p>
+<sect1>Module constructors/destructors Overview<p>
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