@c This is part of the GAS manual.
|
@c This is part of the GAS manual.
|
@c For copying conditions, see the file as.texinfo.
|
@c For copying conditions, see the file as.texinfo.
|
|
|
@ifset GENERIC
|
@ifset GENERIC
|
@page
|
@page
|
@node Z80-Dependent
|
@node Z80-Dependent
|
@chapter Z80 Dependent Features
|
@chapter Z80 Dependent Features
|
@end ifset
|
@end ifset
|
|
|
|
|
@ifclear GENERIC
|
@ifclear GENERIC
|
@node Machine Dependencies
|
@node Machine Dependencies
|
@chapter Z80 Dependent Features
|
@chapter Z80 Dependent Features
|
@end ifclear
|
@end ifclear
|
|
|
@cindex Z80 support
|
@cindex Z80 support
|
@menu
|
@menu
|
* Z80 Options:: Options
|
* Z80 Options:: Options
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* Z80 Syntax:: Syntax
|
* Z80 Syntax:: Syntax
|
* Z80 Floating Point:: Floating Point
|
* Z80 Floating Point:: Floating Point
|
* Z80 Directives:: Z80 Machine Directives
|
* Z80 Directives:: Z80 Machine Directives
|
* Z80 Opcodes:: Opcodes
|
* Z80 Opcodes:: Opcodes
|
@end menu
|
@end menu
|
|
|
@node Z80 Options
|
@node Z80 Options
|
@section Options
|
@section Options
|
@cindex Z80 options
|
@cindex Z80 options
|
@cindex options for Z80
|
@cindex options for Z80
|
The Zilog Z80 and Ascii R800 version of @code{@value{AS}} have a few machine
|
The Zilog Z80 and Ascii R800 version of @code{@value{AS}} have a few machine
|
dependent options.
|
dependent options.
|
@table @option
|
@table @option
|
@cindex @code{-z80} command line option, Z80
|
@cindex @code{-z80} command line option, Z80
|
@item -z80
|
@item -z80
|
Produce code for the Z80 processor. There are additional options to
|
Produce code for the Z80 processor. There are additional options to
|
request warnings and error messages for undocumented instructions.
|
request warnings and error messages for undocumented instructions.
|
@item -ignore-undocumented-instructions
|
@item -ignore-undocumented-instructions
|
@itemx -Wnud
|
@itemx -Wnud
|
Silently assemble undocumented Z80-instructions that have been adopted
|
Silently assemble undocumented Z80-instructions that have been adopted
|
as documented R800-instructions.
|
as documented R800-instructions.
|
@item -ignore-unportable-instructions
|
@item -ignore-unportable-instructions
|
@itemx -Wnup
|
@itemx -Wnup
|
Silently assemble all undocumented Z80-instructions.
|
Silently assemble all undocumented Z80-instructions.
|
@item -warn-undocumented-instructions
|
@item -warn-undocumented-instructions
|
@itemx -Wud
|
@itemx -Wud
|
Issue warnings for undocumented Z80-instructions that work on R800, do
|
Issue warnings for undocumented Z80-instructions that work on R800, do
|
not assemble other undocumented instructions without warning.
|
not assemble other undocumented instructions without warning.
|
@item -warn-unportable-instructions
|
@item -warn-unportable-instructions
|
@itemx -Wup
|
@itemx -Wup
|
Issue warnings for other undocumented Z80-instructions, do not treat any
|
Issue warnings for other undocumented Z80-instructions, do not treat any
|
undocumented instructions as errors.
|
undocumented instructions as errors.
|
@item -forbid-undocumented-instructions
|
@item -forbid-undocumented-instructions
|
@itemx -Fud
|
@itemx -Fud
|
Treat all undocumented z80-instructions as errors.
|
Treat all undocumented z80-instructions as errors.
|
@item -forbid-unportable-instructions
|
@item -forbid-unportable-instructions
|
@itemx -Fup
|
@itemx -Fup
|
Treat undocumented z80-instructions that do not work on R800 as errors.
|
Treat undocumented z80-instructions that do not work on R800 as errors.
|
|
|
@cindex @code{-r800} command line option, Z80
|
@cindex @code{-r800} command line option, Z80
|
@item -r800
|
@item -r800
|
Produce code for the R800 processor. The assembler does not support
|
Produce code for the R800 processor. The assembler does not support
|
undocumented instructions for the R800.
|
undocumented instructions for the R800.
|
In line with common practice, @code{@value{AS}} uses Z80 instruction names
|
In line with common practice, @code{@value{AS}} uses Z80 instruction names
|
for the R800 processor, as far as they exist.
|
for the R800 processor, as far as they exist.
|
@end table
|
@end table
|
|
|
@cindex Z80 Syntax
|
@cindex Z80 Syntax
|
@node Z80 Syntax
|
@node Z80 Syntax
|
@section Syntax
|
@section Syntax
|
The assembler syntax closely follows the 'Z80 family CPU User Manual' by
|
The assembler syntax closely follows the 'Z80 family CPU User Manual' by
|
Zilog.
|
Zilog.
|
In expressions a single @samp{=} may be used as ``is equal to''
|
In expressions a single @samp{=} may be used as ``is equal to''
|
comparison operator.
|
comparison operator.
|
|
|
Suffices can be used to indicate the radix of integer constants;
|
Suffices can be used to indicate the radix of integer constants;
|
@samp{H} or @samp{h} for hexadecimal, @samp{D} or @samp{d} for decimal,
|
@samp{H} or @samp{h} for hexadecimal, @samp{D} or @samp{d} for decimal,
|
@samp{Q}, @samp{O}, @samp{q} or @samp{o} for octal, and @samp{B} for
|
@samp{Q}, @samp{O}, @samp{q} or @samp{o} for octal, and @samp{B} for
|
binary.
|
binary.
|
|
|
The suffix @samp{b} denotes a backreference to local label.
|
The suffix @samp{b} denotes a backreference to local label.
|
|
|
@menu
|
@menu
|
* Z80-Chars:: Special Characters
|
* Z80-Chars:: Special Characters
|
* Z80-Regs:: Register Names
|
* Z80-Regs:: Register Names
|
* Z80-Case:: Case Sensitivity
|
* Z80-Case:: Case Sensitivity
|
@end menu
|
@end menu
|
|
|
@node Z80-Chars
|
@node Z80-Chars
|
@subsection Special Characters
|
@subsection Special Characters
|
|
|
@cindex line comment character, Z80
|
@cindex line comment character, Z80
|
@cindex Z80 line comment character
|
@cindex Z80 line comment character
|
The semicolon @samp{;} is the line comment character;
|
The semicolon @samp{;} is the line comment character;
|
|
|
@cindex location counter, Z80
|
@cindex location counter, Z80
|
@cindex hexadecimal prefix, Z80
|
@cindex hexadecimal prefix, Z80
|
@cindex Z80 $
|
@cindex Z80 $
|
The dollar sign @samp{$} can be used as a prefix for hexadecimal numbers
|
The dollar sign @samp{$} can be used as a prefix for hexadecimal numbers
|
and as a symbol denoting the current location counter.
|
and as a symbol denoting the current location counter.
|
|
|
@cindex character escapes, Z80
|
@cindex character escapes, Z80
|
@cindex Z80, \
|
@cindex Z80, \
|
A backslash @samp{\} is an ordinary character for the Z80 assembler.
|
A backslash @samp{\} is an ordinary character for the Z80 assembler.
|
|
|
@cindex character constant, Z80
|
@cindex character constant, Z80
|
@cindex single quote, Z80
|
@cindex single quote, Z80
|
@cindex Z80 '
|
@cindex Z80 '
|
The single quote @samp{'} must be followed by a closing quote. If there
|
The single quote @samp{'} must be followed by a closing quote. If there
|
is one character in between, it is a character constant, otherwise it is
|
is one character in between, it is a character constant, otherwise it is
|
a string constant.
|
a string constant.
|
|
|
@node Z80-Regs
|
@node Z80-Regs
|
@subsection Register Names
|
@subsection Register Names
|
@cindex Z80 registers
|
@cindex Z80 registers
|
@cindex register names, Z80
|
@cindex register names, Z80
|
|
|
The registers are referred to with the letters assigned to them by
|
The registers are referred to with the letters assigned to them by
|
Zilog. In addition @command{@value{AS}} recognizes @samp{ixl} and
|
Zilog. In addition @command{@value{AS}} recognizes @samp{ixl} and
|
@samp{ixh} as the least and most significant octet in @samp{ix}, and
|
@samp{ixh} as the least and most significant octet in @samp{ix}, and
|
similarly @samp{iyl} and @samp{iyh} as parts of @samp{iy}.
|
similarly @samp{iyl} and @samp{iyh} as parts of @samp{iy}.
|
|
|
@c The @samp{'} in @samp{ex af,af'} may be omitted.
|
@c The @samp{'} in @samp{ex af,af'} may be omitted.
|
|
|
@node Z80-Case
|
@node Z80-Case
|
@subsection Case Sensitivity
|
@subsection Case Sensitivity
|
@cindex Z80, case sensitivity
|
@cindex Z80, case sensitivity
|
@cindex case sensitivity, Z80
|
@cindex case sensitivity, Z80
|
|
|
Upper and lower case are equivalent in register names, opcodes,
|
Upper and lower case are equivalent in register names, opcodes,
|
condition codes and assembler directives.
|
condition codes and assembler directives.
|
The case of letters is significant in labels and symbol names. The case
|
The case of letters is significant in labels and symbol names. The case
|
is also important to distinguish the suffix @samp{b} for a backward reference
|
is also important to distinguish the suffix @samp{b} for a backward reference
|
to a local label from the suffix @samp{B} for a number in binary notation.
|
to a local label from the suffix @samp{B} for a number in binary notation.
|
|
|
@node Z80 Floating Point
|
@node Z80 Floating Point
|
@section Floating Point
|
@section Floating Point
|
@cindex floating point, Z80
|
@cindex floating point, Z80
|
@cindex Z80 floating point
|
@cindex Z80 floating point
|
Floating-point numbers are not supported.
|
Floating-point numbers are not supported.
|
|
|
@node Z80 Directives
|
@node Z80 Directives
|
@section Z80 Assembler Directives
|
@section Z80 Assembler Directives
|
|
|
@command{@value{AS}} for the Z80 supports some additional directives for
|
@command{@value{AS}} for the Z80 supports some additional directives for
|
compatibility with other assemblers.
|
compatibility with other assemblers.
|
|
|
@cindex Z80-only directives
|
@cindex Z80-only directives
|
These are the additional directives in @code{@value{AS}} for the Z80:
|
These are the additional directives in @code{@value{AS}} for the Z80:
|
|
|
@table @code
|
@table @code
|
@item db @var{expression}|@var{string}[,@var{expression}|@var{string}...]
|
@item db @var{expression}|@var{string}[,@var{expression}|@var{string}...]
|
@itemx defb @var{expression}|@var{string}[,@var{expression}|@var{string}...]
|
@itemx defb @var{expression}|@var{string}[,@var{expression}|@var{string}...]
|
For each @var{string} the characters are copied to the object file, for
|
For each @var{string} the characters are copied to the object file, for
|
each other @var{expression} the value is stored in one byte.
|
each other @var{expression} the value is stored in one byte.
|
A warning is issued in case of an overflow.
|
A warning is issued in case of an overflow.
|
|
|
@item dw @var{expression}[,@var{expression}...]
|
@item dw @var{expression}[,@var{expression}...]
|
@itemx defw @var{expression}[,@var{expression}...]
|
@itemx defw @var{expression}[,@var{expression}...]
|
For each @var{expression} the value is stored in two bytes, ignoring
|
For each @var{expression} the value is stored in two bytes, ignoring
|
overflow.
|
overflow.
|
|
|
@item d24 @var{expression}[,@var{expression}...]
|
@item d24 @var{expression}[,@var{expression}...]
|
@itemx def24 @var{expression}[,@var{expression}...]
|
@itemx def24 @var{expression}[,@var{expression}...]
|
For each @var{expression} the value is stored in three bytes, ignoring
|
For each @var{expression} the value is stored in three bytes, ignoring
|
overflow.
|
overflow.
|
|
|
@item d32 @var{expression}[,@var{expression}...]
|
@item d32 @var{expression}[,@var{expression}...]
|
@itemx def32 @var{expression}[,@var{expression}...]
|
@itemx def32 @var{expression}[,@var{expression}...]
|
For each @var{expression} the value is stored in four bytes, ignoring
|
For each @var{expression} the value is stored in four bytes, ignoring
|
overflow.
|
overflow.
|
|
|
@item ds @var{count}[, @var{value}]
|
@item ds @var{count}[, @var{value}]
|
@itemx defs @var{count}[, @var{value}]
|
@itemx defs @var{count}[, @var{value}]
|
@c Synonyms for @code{ds.b},
|
@c Synonyms for @code{ds.b},
|
@c which should have been described elsewhere
|
@c which should have been described elsewhere
|
Fill @var{count} bytes in the object file with @var{value}, if
|
Fill @var{count} bytes in the object file with @var{value}, if
|
@var{value} is omitted it defaults to zero.
|
@var{value} is omitted it defaults to zero.
|
|
|
@item @var{symbol} equ @var{expression}
|
@item @var{symbol} equ @var{expression}
|
@itemx @var{symbol} defl @var{expression}
|
@itemx @var{symbol} defl @var{expression}
|
These directives set the value of @var{symbol} to @var{expression}. If
|
These directives set the value of @var{symbol} to @var{expression}. If
|
@code{equ} is used, it is an error if @var{symbol} is already defined.
|
@code{equ} is used, it is an error if @var{symbol} is already defined.
|
Symbols defined with @code{equ} are not protected from redefinition.
|
Symbols defined with @code{equ} are not protected from redefinition.
|
|
|
@item set
|
@item set
|
This is a normal instruction on Z80, and not an assembler directive.
|
This is a normal instruction on Z80, and not an assembler directive.
|
|
|
@item psect @var{name}
|
@item psect @var{name}
|
A synonym for @xref{Section}, no second argument should be given.
|
A synonym for @xref{Section}, no second argument should be given.
|
@ignore
|
@ignore
|
|
|
The following attributes will possibly be recognized in the future
|
The following attributes will possibly be recognized in the future
|
@table @code
|
@table @code
|
@item abs
|
@item abs
|
The section is to be absolute. @code{@value{AS}} will issue an error
|
The section is to be absolute. @code{@value{AS}} will issue an error
|
message because it can not produce an absolute section.
|
message because it can not produce an absolute section.
|
@item global
|
@item global
|
The section is to be concatenated with other sections of the same name
|
The section is to be concatenated with other sections of the same name
|
by the linker, this is the default.
|
by the linker, this is the default.
|
@item local
|
@item local
|
The section is not global. @code{@value{AS}} will issue a warning if
|
The section is not global. @code{@value{AS}} will issue a warning if
|
object file format is not soff.
|
object file format is not soff.
|
@item ovrld
|
@item ovrld
|
The section is to be overlapped with other sections of the same name by
|
The section is to be overlapped with other sections of the same name by
|
the linker. @code{@value{AS}} will issue an error message
|
the linker. @code{@value{AS}} will issue an error message
|
because it can not mark a section as such.
|
because it can not mark a section as such.
|
@item pure
|
@item pure
|
The section is marked as read only.
|
The section is marked as read only.
|
@end table
|
@end table
|
@end ignore
|
@end ignore
|
|
|
@end table
|
@end table
|
|
|
@node Z80 Opcodes
|
@node Z80 Opcodes
|
@section Opcodes
|
@section Opcodes
|
In line with common practice, Z80 mnemonics are used for both the Z80 and
|
In line with common practice, Z80 mnemonics are used for both the Z80 and
|
the R800.
|
the R800.
|
|
|
In many instructions it is possible to use one of the half index
|
In many instructions it is possible to use one of the half index
|
registers (@samp{ixl},@samp{ixh},@samp{iyl},@samp{iyh}) in stead of an
|
registers (@samp{ixl},@samp{ixh},@samp{iyl},@samp{iyh}) in stead of an
|
8-bit general purpose register. This yields instructions that are
|
8-bit general purpose register. This yields instructions that are
|
documented on the R800 and undocumented on the Z80.
|
documented on the R800 and undocumented on the Z80.
|
Similarly @code{in f,(c)} is documented on the R800 and undocumented on
|
Similarly @code{in f,(c)} is documented on the R800 and undocumented on
|
the Z80.
|
the Z80.
|
|
|
The assembler also supports the following undocumented Z80-instructions,
|
The assembler also supports the following undocumented Z80-instructions,
|
that have not been adopted in the R800 instruction set:
|
that have not been adopted in the R800 instruction set:
|
@table @code
|
@table @code
|
@item out (c),0
|
@item out (c),0
|
Sends zero to the port pointed to by register c.
|
Sends zero to the port pointed to by register c.
|
|
|
@item sli @var{m}
|
@item sli @var{m}
|
Equivalent to @code{@var{m} = (@var{m}<<1)+1}, the operand @var{m} can
|
Equivalent to @code{@var{m} = (@var{m}<<1)+1}, the operand @var{m} can
|
be any operand that is valid for @samp{sla}. One can use @samp{sll} as a
|
be any operand that is valid for @samp{sla}. One can use @samp{sll} as a
|
synonym for @samp{sli}.
|
synonym for @samp{sli}.
|
|
|
@item @var{op} (ix+@var{d}), @var{r}
|
@item @var{op} (ix+@var{d}), @var{r}
|
This is equivalent to
|
This is equivalent to
|
|
|
@example
|
@example
|
ld @var{r}, (ix+@var{d})
|
ld @var{r}, (ix+@var{d})
|
@var{opc} @var{r}
|
@var{opc} @var{r}
|
ld (ix+@var{d}), @var{r}
|
ld (ix+@var{d}), @var{r}
|
@end example
|
@end example
|
|
|
The operation @samp{@var{opc}} may be any of @samp{res @var{b},},
|
The operation @samp{@var{opc}} may be any of @samp{res @var{b},},
|
@samp{set @var{b},}, @samp{rl}, @samp{rlc}, @samp{rr}, @samp{rrc},
|
@samp{set @var{b},}, @samp{rl}, @samp{rlc}, @samp{rr}, @samp{rrc},
|
@samp{sla}, @samp{sli}, @samp{sra} and @samp{srl}, and the register
|
@samp{sla}, @samp{sli}, @samp{sra} and @samp{srl}, and the register
|
@samp{@var{r}} may be any of @samp{a}, @samp{b}, @samp{c}, @samp{d},
|
@samp{@var{r}} may be any of @samp{a}, @samp{b}, @samp{c}, @samp{d},
|
@samp{e}, @samp{h} and @samp{l}.
|
@samp{e}, @samp{h} and @samp{l}.
|
|
|
@item @var{opc} (iy+@var{d}), @var{r}
|
@item @var{opc} (iy+@var{d}), @var{r}
|
As above, but with @samp{iy} instead of @samp{ix}.
|
As above, but with @samp{iy} instead of @samp{ix}.
|
@end table
|
@end table
|
|
|
The web site at @uref{http://www.z80.info} is a good starting place to
|
The web site at @uref{http://www.z80.info} is a good starting place to
|
find more information on programming the Z80.
|
find more information on programming the Z80.
|
|
|
|
|
