<title>ca65 Users Guide
<author><url url="mailto:uz@cc65.org" name="Ullrich von Bassewitz">,<newline>
<url url="mailto:greg.king5@verizon.net" name="Greg King">
-<date>2015-11-17
<abstract>
ca65 is a powerful macro assembler for the 6502, 65C02, and 65816 CPUs. It is
Set the default for the CPU type. The option takes a parameter, which
may be one of
- 6502, 65SC02, 65C02, 65816, sweet16, HuC6280
+ 6502, 6502X, 65SC02, 65C02, 65816, sweet16, HuC6280, 4510
<label id="option-create-dep">
<tt><ref id=".PSC02" name=".PSC02"></tt> command was given).
<item>all valid 65C02 mnemonics when in 65C02 mode (after the
<tt><ref id=".PC02" name=".PC02"></tt> command was given).
-<item>all valid 65618 mnemonics when in 65816 mode (after the
+<item>all valid 65816 mnemonics when in 65816 mode (after the
<tt><ref id=".P816" name=".P816"></tt> command was given).
+<item>all valid 4510 mnemonics when in 4510 mode (after the
+ <tt><ref id=".P4510" name=".P4510"></tt> command was given).
</itemize>
In 65816 mode, several aliases are accepted, in addition to the official
mnemonics:
-<tscreen><verb>
-CPA is an alias for CMP
-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
-TAS is an alias for TCS
-TDA is an alias for TDC
-TSA is an alias for TSC
-</verb></tscreen>
+<itemize>
+<item><tt>CPA</tt> is an alias for <tt>CMP</tt>
+<item><tt>DEA</tt> is an alias for <tt>DEC A</tt>
+<item><tt>INA</tt> is an alias for <tt>INC A</tt>
+<item><tt>SWA</tt> is an alias for <tt>XBA</tt>
+<item><tt>TAD</tt> is an alias for <tt>TCD</tt>
+<item><tt>TAS</tt> is an alias for <tt>TCS</tt>
+<item><tt>TDA</tt> is an alias for <tt>TDC</tt>
+<item><tt>TSA</tt> is an alias for <tt>TSC</tt>
+</itemize>
<sect1>6502X mode<label id="6502X-mode"><p>
</itemize>
+<sect1>4510 mode<p>
+
+The 4510 is a microcontroller that is the core of the Commodore C65 aka C64DX.
+It contains among other functions a slightly modified 65CE02/4502 CPU, to allow
+address mapping for 20 bits of address space (1 megabyte addressable area).
+As compared to the description of the CPU in the
+<url url="http://www.zimmers.net/anonftp/pub/cbm/c65/c65manualupdated.txt.gz"
+name="C65 System Specification">
+<url url="https://raw.githubusercontent.com/MEGA65/c65-specifications/master/c65manualupdated.txt"
+name="(updated version)"> uses these changes:
+<itemize>
+<item><tt>LDA (d,SP),Y</tt> may also be written as <tt>LDA (d,S),Y</tt>
+(matching the 65816 notataion).
+<item>All branch instruction allow now 16 bit offsets. To use a 16 bit
+branch you have to prefix these with an "L" (e.g. "<tt>LBNE</tt>" instead of
+"<tt>BNE</tt>"). This might change at a later implementation of the assembler.
+</itemize>
+For more information about the Commodore C65/C64DX and the 4510 CPU, see
+<url url="http://www.zimmers.net/anonftp/pub/cbm/c65/"> and
+<url url="https://en.wikipedia.org/wiki/Commodore_65" name="Wikipedia">.
+
<sect1>sweet16 mode<label id="sweet16-mode"><p>
<sect1>Address sizes of symbols<p>
+The address size of a symbol can be specified with a prefix:
+
+<itemize>
+<item>z: zeropage addressing (8 bits).
+<item>a: absolute addressing (16 bits).
+<item>f: far addressing (24 bits).
+</itemize>
+
+The zeropage addressing override can be used to ensure the use of optimal
+zeropage instructions, or correct cases where the size isn't yet known
+due to the single-pass assembly model.
+The larger addressing overrides can be used to promote a smaller address
+to absolute or far addressing, instead of being automatically fit into
+a smaller addressing type.
<sect1>Memory models<p>
<tscreen><verb>
; Reserve space for the larger of two data blocks
- savearea: .max (.sizeof (foo), .sizeof (bar))
+ savearea: .res .max (.sizeof (foo), .sizeof (bar))
</verb></tscreen>
See: <tt><ref id=".MIN" name=".MIN"></tt>
Example:
<tscreen><verb>
- ; Reserve space for some data, but 256 bytes minimum
- savearea: .min (.sizeof (foo), 256)
+ ; Reserve space for some data, but 256 bytes maximum
+ savearea: .res .min (.sizeof (foo), 256)
</verb></tscreen>
See: <tt><ref id=".MAX" name=".MAX"></tt>
<sect1><tt>.CHARMAP</tt><label id=".CHARMAP"><p>
Apply a custom mapping for characters. The command is followed by two
- numbers. The first one is the index of the source character (range 1..255),
+ numbers. The first one is the index of the source character (range 0..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>
+ character and string constants <em/when/ they generate output; and, overrides
+ a mapping table specified with the <tt><ref id="option-t" name="-t"></tt>
command line switch.
Example:
-
<tscreen><verb>
- .charmap $41, $61 ; Map 'A' to 'a'
+ .charmap $41, $61 ; Map 'A' to 'a'
</verb></tscreen>
<tag><tt>at_in_identifiers</tt><label id="at_in_identifiers"></tag>
- Accept the at character (`@') as a valid character in identifiers. The
+ Accept the at character ('@') as a valid character in identifiers. The
at character is not allowed to start an identifier, even with this
feature enabled.
<tag><tt>dollar_in_identifiers</tt><label id="dollar_in_identifiers"></tag>
- Accept the dollar sign (`$') as a valid character in identifiers. The
+ Accept the dollar sign ('$') as a valid character in identifiers. The
dollar character is not allowed to start an identifier, even with this
feature enabled.
<tag><tt>dollar_is_pc</tt><label id="dollar_is_pc"></tag>
- The dollar sign may be used as an alias for the star (`*'), which
+ The dollar sign may be used as an alias for the star ('*'), which
gives the value of the current PC in expressions.
Note: Assignment to the pseudo variable is not allowed.
<tag><tt>leading_dot_in_identifiers</tt><label id="leading_dot_in_identifiers"></tag>
- Accept the dot (`.') as the first character of an identifier. This may be
+ Accept the dot ('.') as the first character of an identifier. This may be
used for example to create macro names that start with a dot emulating
control directives of other assemblers. Note however, that none of the
reserved keywords built into the assembler, that starts with a dot, may be
<tag><tt>pc_assignment</tt><label id="pc_assignment"></tag>
- Allow assignments to the PC symbol (`*' or `$' if <tt/dollar_is_pc/
+ Allow assignments to the PC symbol ('*' or '$' if <tt/dollar_is_pc/
is enabled). Such an assignment is handled identical to the <tt><ref
id=".ORG" name=".ORG"></tt> command (which is usually not needed, so just
removing the lines with the assignments may also be an option when porting
Conditional assembly: Check if there are any remaining tokens in this line,
and evaluate to FALSE if this is the case, and to TRUE otherwise. If the
condition is not true, further lines are not assembled until an <tt><ref
- id=".ELSE" name=".ESLE"></tt>, <tt><ref id=".ELSEIF" name=".ELSEIF"></tt> or
+ id=".ELSE" name=".ELSE"></tt>, <tt><ref id=".ELSEIF" name=".ELSEIF"></tt> or
<tt><ref id=".ENDIF" name=".ENDIF"></tt> directive.
This command is often used to check if a macro parameter was given. Since an
(see <tt><ref id=".P02" name=".P02"></tt> command).
+<sect1><tt>.IFP4510</tt><label id=".IFP4510"><p>
+
+ Conditional assembly: Check if the assembler is currently in 4510 mode
+ (see <tt><ref id=".P4510" name=".P4510"></tt> command).
+
+
<sect1><tt>.IFP816</tt><label id=".IFP816"><p>
Conditional assembly: Check if the assembler is currently in 65816 mode
<tt><ref id="option--cpu" name="--cpu"></tt> command line option.
See: <tt><ref id=".PC02" name=".PC02"></tt>, <tt><ref id=".PSC02"
- name=".PSC02"></tt> and <tt><ref id=".P816" name=".P816"></tt>
+ name=".PSC02"></tt>, <tt><ref id=".P816" name=".P816"></tt> and
+ <tt><ref id=".P4510" name=".P4510"></tt>
+
+
+<sect1><tt>.P4510</tt><label id=".P4510"><p>
+
+ Enable the 4510 instruction set. This is a superset of the 65C02 and
+ 6502 instruction sets.
+
+ 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>
<sect1><tt>.P816</tt><label id=".P816"><p>
6502 instruction sets.
See: <tt><ref id=".P02" name=".P02"></tt>, <tt><ref id=".PSC02"
- name=".PSC02"></tt> and <tt><ref id=".PC02" name=".PC02"></tt>
+ name=".PSC02"></tt>, <tt><ref id=".PC02" name=".PC02"></tt> and
+ <tt><ref id=".P4510" name=".P4510"></tt>
<sect1><tt>.PAGELEN, .PAGELENGTH</tt><label id=".PAGELENGTH"><p>
6502 and 65SC02 instructions.
See: <tt><ref id=".P02" name=".P02"></tt>, <tt><ref id=".PSC02"
- name=".PSC02"></tt> and <tt><ref id=".P816" name=".P816"></tt>
+ name=".PSC02"></tt>, <tt><ref id=".P816" name=".P816"></tt> and
+ <tt><ref id=".P4510" name=".P4510"></tt>
<sect1><tt>.POPCPU</tt><label id=".POPCPU"><p>
6502 instructions.
See: <tt><ref id=".P02" name=".P02"></tt>, <tt><ref id=".PC02"
- name=".PC02"></tt> and <tt><ref id=".P816" name=".P816"></tt>
+ name=".PC02"></tt>, <tt><ref id=".P816" name=".P816"></tt> and
+ <tt><ref id=".P4510" name=".P4510"></tt>
<sect1><tt>.PUSHCPU</tt><label id=".PUSHCPU"><p>
page and direct (short) addressing is possible for data in this segment.
Beware: Only labels in a segment with the zeropage attribute are marked
- as reachable by short addressing. The `*' (PC counter) operator will
+ as reachable by short addressing. The '*' (PC counter) operator will
work as in other segments and will create absolute variable values.
Please note that a segment cannot have two different address sizes. A
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 and HuC6280.
+ namely: 6502, 6502X, 65SC02, 65C02, 65816, 4510 and HuC6280.
See: <tt><ref id=".CPU" name=".CPU"></tt>,
<tt><ref id=".IFP02" name=".IFP02"></tt>,
<tt><ref id=".IFPSC02" name=".IFPSC02"></tt>,
<tt><ref id=".P02" name=".P02"></tt>,
<tt><ref id=".P816" name=".P816"></tt>,
+ <tt><ref id=".P4510" name=".P4510"></tt>,
<tt><ref id=".PC02" name=".PC02"></tt>,
<tt><ref id=".PSC02" name=".PSC02"></tt>
some things may be done with both macro types, each type has special
usages. The types complement each other.
+<item> Parentheses work differently from C macros.
+ The common practice of wrapping C macros in parentheses may cause
+ unintended problems here, such as accidentally implying an
+ indirect addressing mode. While the definition of a macro requires
+ parentheses around its argument list, when invoked they should not be
+ included.
+
</itemize>
Let's look at a few examples to make the advantages and disadvantages
DEBUG "Assembling include file #3"
</verb></tscreen>
-Note that, while formal parameters have to be placed in braces, this is
-not true for the actual parameters. Beware: Since the assembler cannot
-detect the end of one parameter, only the first token is used. If you
-don't like that, use classic macros instead:
+Note that, while formal parameters have to be placed in parentheses,
+the actual argument used when invoking the macro should not be.
+The invoked arguments are separated by commas only, if parentheses are
+used by accident they will become part of the replaced token.
+
+If you wish to have an expression follow the macro invocation, the
+last parameter can be enclosed in curly braces {} to indicate the end of that
+argument.
+
+Examples:
<tscreen><verb>
-.macro DEBUG message
- .out message
-.endmacro
+.define COMBINE(ta,tb,tc) ta+tb*10+tc*100
+
+.word COMBINE 5,6,7 ; 5+6*10+7*100 = 765
+.word COMBINE(5,6,7) ; (5+6*10+7)*100 = 7200 ; incorrect use of parentheses
+.word COMBINE 5,6,7+1 ; 5+6*10+7+1*100 = 172
+.word COMBINE 5,6,{7}+1 ; 5+6*10+7*100+1 = 766 ; {} encloses the argument
+.word COMBINE 5,6-2,7 ; 5+6-2*10+7*100 = 691
+.word COMBINE 5,(6-2),7 ; 5+(6-2)*10+7*100 = 745
+.word COMBINE 5,6,7+COMBINE 0,1,2 ; 5+6*10+7+0+1*10+2*100*100 = 20082
+.word COMBINE 5,6,{7}+COMBINE 0,1,2 ; 5+6*10+7*100+0+1*10+2*100 = 975
</verb></tscreen>
-(That is an example where a problem can be solved with both macro types).
+With C macros it is common to enclose the results in parentheses to
+prevent unintended interactions with the text of the arguments, but
+additional care must be taken in this assembly context where parentheses
+may alter the meaning of a statement. In particular, indirect addressing modes
+may be accidentally implied:
+
+<tscreen><verb>
+.define DUO(ta,tb) (ta+(tb*10))
+
+ lda DUO(5,4), Y ; LDA (indirect), Y
+ lda 0+DUO(5,4), Y ; LDA absolute indexed, Y
+</verb></tscreen>
<sect1>Characters in macros<p>
+<sect1><tt>.MACPACK apple2</tt><p>
+
+This macro package defines a macro named <tt/scrcode/. It takes a string
+as argument and places this string into memory translated into screen codes.
+
+
<sect1><tt>.MACPACK atari</tt><p>
This macro package defines a macro named <tt/scrcode/. It takes a string
CPU_65816
CPU_SWEET16
CPU_HUC6280
+ CPU_4510
</verb></tscreen>
is defined. These constants may be used to determine the exact type of the
CPU_ISET_65816
CPU_ISET_SWEET16
CPU_ISET_HUC6280
+ CPU_ISET_4510
</verb></tscreen>
The value read from the <tt/<ref id=".CPU" name=".CPU">/ pseudo variable may
<itemize>
<item><tt/__APPLE2__/ - Target system is <tt/apple2/ or <tt/apple2enh/
<item><tt/__APPLE2ENH__/ - Target system is <tt/apple2enh/
+<item><tt/__ATARI2600__/ - Target system is <tt/atari2600/
<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/
projects / cc65 / blobdiff