diff options
| author | Ian C <ianc@noddybox.co.uk> | 2016-03-19 00:35:45 +0000 |
|---|---|---|
| committer | Ian C <ianc@noddybox.co.uk> | 2016-03-19 00:35:45 +0000 |
| commit | 618d4de3bd173a7bda6d6a2b911bc0717c10102b (patch) | |
| tree | 59bfa460faf151642e840f22daf5e5394321e1f0 /doc | |
| parent | 4564c7906be89463b8f9637685e1785dd900f4b3 (diff) | |
Moved documentation to an hand-crafted HTML file.
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/Makefile | 32 | ||||
| -rw-r--r-- | doc/README | 2 | ||||
| -rw-r--r-- | doc/casm.html | 1113 | ||||
| -rw-r--r-- | doc/manual.asciidoc | 587 |
4 files changed, 1114 insertions, 620 deletions
diff --git a/doc/Makefile b/doc/Makefile deleted file mode 100644 index 9fb7486..0000000 --- a/doc/Makefile +++ /dev/null @@ -1,32 +0,0 @@ -# casm - Simple, portable assembler -# -# Copyright (C) 2003-2015 Ian Cowburn (ianc@noddybox.demon.co.uk) -# -# This program is free software: you can redistribute it and/or modify -# it under the terms of the GNU General Public License as published by -# the Free Software Foundation, either version 3 of the License, or -# (at your option) any later version. -# -# This program is distributed in the hope that it will be useful, -# but WITHOUT ANY WARRANTY; without even the implied warranty of -# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -# GNU General Public License for more details. -# -# You should have received a copy of the GNU General Public License -# along with this program. If not, see <http://www.gnu.org/licenses/>. -# -# ------------------------------------------------------------------------- -# -# Makefile for documentation -# - -all: manual.html manual.pdf - -manual.html: manual.asciidoc - asciidoc manual.asciidoc - -manual.pdf: manual.asciidoc - a2x manual.asciidoc - -clean: - rm -f manual.html manual.pdf manual.xml @@ -17,6 +17,6 @@ You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. - See manual.pdf or manual.html for instructions on use. + See casm.html for instructions on use. See LICENSE for full license text. diff --git a/doc/casm.html b/doc/casm.html new file mode 100644 index 0000000..d3a545b --- /dev/null +++ b/doc/casm.html @@ -0,0 +1,1113 @@ +<html> +<head> + +<title>CASM - A simple, portable multi-pass assembler</title> + +<style> + +h1 +{ + padding-top: 20px; + padding-top: 10px; +} + +h2 +{ + padding-top: 20px; + padding-top: 10px; +} + +body +{ + background-color: white; + color: black; + font-family: sans-serif; + font-weight: normal; + width: 80%; + margin: auto; +} + +.legalise +{ + font-variant: small-caps; + font-size: 80%; + width: 45%; +} + +.codeblock +{ + font-family: monospace; + border: 1px solid black; + width: 100%; + background-color: #e0e0ff; + padding: 5px; +} + +li +{ + padding-bottom: 3px; +} + +table +{ + padding-top: 10px; + padding-bottom: 10px; +} + +tr +{ + padding-bottom: 5px; +} + +thead +{ + font-weight: bold; + background-color: black; + color: white; + white-space: nowrap; + font-variant: small-caps; +} + +td.head +{ + vertical-align: top; + padding: 10px; +} + +td.cmd +{ + vertical-align: top; + padding: 5px; + font-family: monospace; + font-weight: bold; + background-color: #e0e0e0; + white-space: nowrap; +} + +td.def +{ + padding-left: 10px; + padding-top: 5px; + padding-bottom: 5px; + vertical-align: top; +} + +td.alias +{ + padding-left: 10px; + padding-top: 5px; + padding-bottom: 5px; + vertical-align: top; + font-family: monospace; + background-color: #e0e0e0; + white-space: nowrap; +} + +h1 +{ + border-top: 2px solid black; +} + +h2 +{ + border-top: 1px solid #888888; +} + +</style> + +</head> + +<body> + +<div class="legalise"> +<p><b>casm</b> is a simple, portable multi-pass assembler</p> + +<p>Copyright (C) 2003-2015 Ian Cowburn</p> + +<p>This program is free software: you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version.</p> + +<p>This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details.</p> + +<p>You should have received a copy of the GNU General Public License +along with this program. If not, see +<a href="http://www.gnu.org/licenses/gpl-3.0.html"> +http://www.gnu.org/licenses/gpl-3.0.html)</a></p> +</div> + + +<h1>CASM</h1> + +<h2>Usage</h2> + +<div class="codeblock"> +casm <i>file</i> +</div> + +<p>Assembles <i>file</i>, and places the resulting code in a file called +<b>output</b> by default.</p> + +<p>Note that switches aren't used by <b>casm</b>. Instead options are +controlled by commands in the source <i>file</i>.</p> + + +<h2>Memory Layout</h2> + +<p>There is 64K of RAM that the assembler will generate output into. Extra 64K +banks of RAM can be added by using the <b>bank</b> or <b>org</b> directives. +Banks are numbered from zero upwards.</p> + + +<h2>Source Code</h2> + +<h3>Layout</h3> + +The source files follow this basic format: + +<pre class="codeblock"> + ; Comments + ; + label1: equ 0xffff + + org $4000; + + db "Hello, World\n",0 + + main jp local_label ; Comments + + .local_label + inc a + + another: + inc b + jp local_label ; Actually jumps to the following + ; local_label. + + .local_label + ret +</pre> + + +<p>The source files follow the following rules:</p> + +<ul> + +<li>Any text past a semicolon (;) is discarded as a comment (except when part +of a string constant).</li> + +<li>Labels must start in column zero (the left hand most column).</li> + + <ul> + <li>If the label ends with a colon (:) then the colon is removed.</li> + + <li>If the label doesn't start with a period (.) then it is assumed a global + label.</li> + + <li>If the label starts with a period (.) then it is assumed to be a local + label. Local labels are associated with the preceding global label. + If a global label and related local label have the same name, the local + label will be used on expansion.</li> + + <li>Any label can be followed by an <code>equ</code> directive, in which case + the label is set to that value rather than the current program counter.</li> + + <li>Labels are case-insensitive.</li> + +</ul> + +<li>Directives and opcodes must appear further along the line (anywhere else +other than the left hand column where labels live basically).</li> + +<li>Strings can either be quoted with single or double quotes; this allows you +to put the other quote type inside the string.</li> + +</ul> + + +<h3>Recognised directives</h3> + +<p>The following directives are also recognised with an optional period (.) in +front of them, and are case insensitive. Directives can also be used to +control the output of a program listing, and the output of the assembly +itself. These are documented in subsequent sections.</p> + +<table> + +<thead><tr><td class="head">Directive</td> +<td class="head">Description</td></tr></thead> +<tr> + +<td class="cmd"> +processor <i>cpu</i> +</td> + +<td class="def"> +Sets the processor type to <i>CPU</i>. If omitted then Z80 is the default. +Note that this can appear multiple times in the same file. See the later +sections on processors to see what values are supported.</p> +</td></tr> + +<tr><td class="cmd"> +option <i>setting</i>, <i>value</i> +</td> + +<td class="def"> +Set options. Options are defined later on, and each CPU and output driver +can also have its own options. For options that support booleans +(on/off/true/false),the <i>setting</i> can be prefixed with a plus or minus +character to switch it on or off respectively. +</td></tr> + +<tr><td class="cmd"> +equ <i>value</i></code> +</td> +<td class="def"> +Sets the top level label to <i>value</i>. Note this requires a label on the +same line as this directive. +</td></tr> + +<tr><td class="cmd"> +org <i>value</i>[, <i>bank</i>] +</td> +<td class="def"> +Sets the program counter (PC) to <i>value</i>. The PC defaults to zero on +initialisation. If the optional second argument is passed the current memory +bank in use is set to <i>bank</i>. +</td></tr> + +<tr><td class="cmd"> +bank <i>value</i> +</td> +<td class="def"> +The current memory bank in use is set to <i>value</i>. +</td></tr> + +<tr><td class="cmd"> +ds <i>value</i>[, <i>fill</i>] +</td> +<td class="def"> +Skips the program counter on <i>value</i> bytes. If the optional <i>fill</i> is +provided then the bytes are filled with <i>fill</i>, otherwise they are filled +with zero. +</td> + +<tr><td class="cmd"> +db <i>value</i>[, <i>value</i>] +</td> +<td class="def"> +Writes bytes represented by <i>value</i> to the current PC. The values can be +constants, expressions, labels or strings which are expanded to a list of byte +values for each character in the string. +</td></tr> + +<tr><td class="cmd"> +dw <i>value</i>[, <i>value</i>] +</td> +<td class="def"> +Writes words (16-bit values) represented by <i>value</i> to the current PC. +The values can be constants, expressions, labels or strings. Strings are +written as 16-bit versions of their byte values, i.e. the high byte will be zero +and the low byte the character code. +</td></tr> + +<tr><td class="cmd"> +align <i>value</i>[, <i>fill</i>] +</td> +<td class="def"> +Align the PC so that (PC modulus <i>value</i>) is zero. Will error if +<i>value</i> is less than 2 or greater that 32768. No values are written to +the skipped bytes unless the optional <i>fill</i> is supplied. +</td></tr> + +<tr><td class="cmd"> +include <i>filename</i></code> +</td> +<td class="def"> +Includes the source file <i>filename</i> as if it was text entered at the +current location. +</td></tr> + +<tr><td class="cmd"> +incbin <i>filename</i> +</td> +<td class="def"> +Includes the binary file <i>filename</i> at the current PC, as if it was a +sequence of <code>db</code> directives with all the bytes from the file. +</td></tr> + +<tr><td class="cmd"> +alias <i>command</i>, <i>replacement</i> +</td> +<td class="def"> +Creates an alias so that whenever the command <i>command</i> is found in the +source it is replaced with <i>replacement</i>. The idea of this is to make it +easier to import sources that use unknown directives, e.g. + +<pre class="codeblock"> + alias setaddr,org + alias ldreg,ld + + cpu z80 + + setaddr $8000 ; These two are + org $8000 ; equivalent. + + ld a,(hl) ; These two are + ldreg a,(hl) ; equivalent. +</pre> +</td></tr> + +<tr><td class="cmd"> +nullcmd +</td> +<td class="def"> +Simply does nothing. It's only real use is as an alias if you wished to +strip a directive from a foreign source file. +</td></tr> + +<tr><td class="cmd"> +end +</td> +<td class="def"> +Terminates input processing. Anything past the directive will be ignored. +</td></tr> +</table> + +<h3>Built-in Aliases</h3> + +The following are built-in aliases for the above directives. + +<table> + +<thead><tr><td class="head">Command</td> +<td class="head">Built-in Alias</td></tr></thead> + +<tr><td class="cmd">equ</td> +<td class="alias"> +eq +</td></tr> + +<tr><td class="cmd">ds</td> +<td class="alias"> +defs +</td></tr> + +<tr><td class="cmd">db</td> +<td class="alias"> +defb<br> +byte<br> +text<br> +</td></tr> + +<tr><td class="cmd">dw</td> +<td class="alias"> +defw<br> +word<br> +</td></tr> + +</table> + +<h3>Expressions</h3> + +<p>In any of the directives above, where a value is defined, an expression can +be entered.</p> + +<p>Assembly instructions will also permit these expressions to be used where +applicable. As many opcodes use parenthesis to indicate addressing modes, +remember that {} brackets can be used to alter expression precedence.</p> + +<pre class="codeblock"> + ld a,{8+2}*2 ; On the Z80 loads A with the value 20 + ld a,({8+2}*2) ; On the Z80 loads A with the value stored at + ; address 20 +</pre> + +<p>Note that the expression is evaluated using a standard C int, and then cast +to the appropriate size.</p> + +<p>The following formats for constant numbers are supported:</p> + +<table> + +<thead><tr><td class="head">Format (regular expression)</td> +<td class="head">Description</td></tr></thead> + +<tr><td class="cmd"> +"." <i>or</i> '.' +</td> +<td class="def"> +A single quoted character will be converted into the appropriate character +code. +</td></tr> + +<tr><td class="cmd"> +[1-9][0-9]* +</td> +<td class="def"> +A decimal number, e.g. 42. +</td></tr> + +<tr><td class="cmd"> +0[0-7]* +</td> +<td class="def"> +An octal number, e.g. 052. +</td></tr> + +<tr><td class="cmd"> +0x[0-9a-fA-f]+ +</td> +<td class="def"> +A hex number, e.g. 0x2a. +</td></tr> + +<tr><td class="cmd"> +[0-9a-fA-f]+h +</td> +<td class="def"> +A hex number, e.g. 2ah. +</td></tr> + +<tr><td class="cmd"> +$[0-9a-fA-f]+ +</td> +<td class="def"> +A hex number, e.g. $2a. +</td></tr> + +<tr><td class="cmd"> +[01]+b +</td> +<td class="def"> +A binary number, e.g. 00101010b +</td></tr> + +<tr><td class="cmd"> +[a-zA-Z_0-9]+ +</td> +<td class="def"> +A label, e.g. `main_loop`. +</td></tr> + +</table> + +The following operators are understood. The order here is the order of +precedence. + +<table> + +<thead><tr><td class="head">Arithmetic Operators</td> +<td class="head">Description</td></tr></thead> + +<tr><td class="cmd"> +{ } +</td> +<td class="def"> +Brackets used to alter the order of precedence. Note normal parenthesis +aren't used as the assembly language may make use of them. +</td></tr> + +<tr><td class="cmd"> +~ + - +</td> +<td class="def"> +Bitwise NOT/unary plus/unary minus. +</td></tr> + +<tr><td class="cmd"> +<< >> +</td> +<td class="def"> +Shift left/shift right. +</td></tr> + +<tr><td class="cmd"> +/ * % +</td> +<td class="def"> +Division/multiplication/modulus. +</td></tr> + +<tr><td class="cmd"> ++ - +</td> +<td class="def"> +Addition/subtraction. +</td></tr> + +</table> + +All the following have the same precedence, and so will be done left to right. + +<table> + +<thead><tr><td class="head">Comparison Operators</td> +<td class="head">Description</td></tr></thead> + +<tr><td class="cmd"> +== +</td> +<td class="def"> +Equality. Returns 1 if the arguments are equal, otherwise zero. +</td></tr> + +<tr><td class="cmd"> +!= +</td> +<td class="def"> +Inequality. Returns 1 if the arguments are unequal, otherwise zero. +</td></tr> + +<tr><td class="cmd"> +< <= > >= +</td> +<td class="def"> +Less than/less than or equal/greater than/greater than or equal. Returns 1 +if the arguments are equal, otherwise zero. +</td></tr> + +</table> + +All the following have the same precedence, and so will be done left to right. + +<table> + +<thead><tr><td class="head">Boolean Operators</td> +<td class="head">Description</td></tr></thead> + +<tr><td class="cmd"> +&& & +</td> +<td class="def"> +Boolean/bitwise AND. For boolean operation arguments, zero is FALSE, +otherwise TRUE. +</td></tr> + +<tr><td class="cmd"> +|| | +</td> +<td class="def"> +Boolean/bitwise OR. +</td></tr> + +<tr><td class="cmd"> +^ +</td> +<td class="def"> +Bitwise XOR. +</td></tr> + +</table> + +<h3>Character Sets</h3> + +<p>The assembler has built-in support for a few different character sets. +These can be set by using the options `charset` or `codepage`, i.e.</p> + +<pre class="codeblock"> + option codepage, <i>format</i> + option charset, <i>format</i> +</pre> + +<p>The following values can be used for <i>format</i>.</p> + +<table> + +<thead><tr><td class="head">Format</td> +<td class="head">Description</td></tr></thead> + +<tr><td class="cmd"> +ascii +</td> +<td class="def"> +7-bit ASCII. This is the default. +</td></tr> + +<tr><td class="cmd"> +spectrum +</td> +<td class="def"> +The character codes as used on the Sinclair ZX Spectrum. +</td></tr> + +<tr><td class="cmd"> +zx81 +</td> +<td class="def"> +The character codes as used on the Sinclair ZX-81. Lower case +letters are encoded as normal upper case letters and upper case +letter will be encoded as inverse upper case letters. +</td></tr> + +<tr><td class="cmd"> +cbm +</td> +<td class="def"> +PETSCII as used on the Commodore Business Machine's range from the +PET to the C128. See <a href="https://en.wikipedia.org/wiki/PETSCII"> +https://en.wikipedia.org/wiki/PETSCII</a> more details. +</td></tr> +</table> + +<p>e.g.</p> + +<pre class="codeblock"> + option +list + option +list-hex + + option charset,ascii + db "Hello",'A' + ; $48 $65 $6C $6C $6F $41 + + option charset,zx81 + db "Hello",'A' + ; $AD $2A $31 $31 $34 $A6 + + option codepage,cbm + db "Hello",'A' + ; $48 $45 $4C $4C $4F $41 + + option codepage,spectrum + db "Hello",'A' + ; $48 $65 $6C $6C $6F $41 +</pre> + + +<h3>Macros</h3> + +<p> +Macros can be defined in one of two ways; either parameterless or with named +parameters. Macro names are case-insensitive. In the parameterless mode the +special identifier '*' can be used to expand all arguments, which will be +separated with commas. +</p> + +<p> +When expanded the macro will have an internally generated top-level label +assigned to it, so local variables will work inside the macro. +</p> + +<p>e.g.</p> + +<pre class="codeblock"> +macro1: macro + + ld a,\1 + ld b,\2 + ld hl,data + call \3 + jr dataend +.data + defb \* +.dataend + + endm + +macro2: macro char,junk,interface + + ld a,@char + ld b,@junk + call @interface + + endm +</pre> + +<p> +Note that trying to expand and unknown/missing argument will be replaced with +an empty string. Also the two argument reference styles can be mixed, though +obviously the @ form only makes sense in a parameterised macro, e.g. +</p> + +<pre class="codeblock"> +mac: macro char,junk,interface + + ld a,@char + ld b,\2 + call @interface + + endm +</pre> + +<p> +The at symbol (@) used for parameter expansion in named argument macros can +be replaced by using the following option, e.g. +</p> + +<pre class="codeblock"> + option macro-arg-char,& +</pre> + +<p> +Note that this is enforced when the macro is *used*, not when it is *defined*. +Also the character must not be quoted, as that will be parsed as a string +holding the character code of the character. +</p> + + +<h3>Output Format</h3> + +By default the assembled code is written to a file called `output` as raw +binary covering the block of memory that the assembly touched. If memory +banks have been used then *output* is appended with the memory bank number, so +that a separate output file is generated for each bank. + +The generated output can be controlled with the following options. + +<table> + +<thead><tr><td class="head">Output Option</td> +<td class="head">Description</td></tr></thead> + +<tr><td class="cmd"> +option output-file, <i>file</i> +</td> +<td class="def"> +Send the output to <i>file</i>. +</td></tr> + +<tr><td class="cmd"> +option output-type, <i>format</i> +</td> +<td class="def"> +Controls the format of the output file. The following are the +supported output formats: + +<table> + +<tr><td class="cmd"> +raw +</td> +<td class="def"> +A simply raw binary image of the memory. +</td></tr> + +<tr><td class="cmd"> +spectrum +</td> +<td class="def"> +<p> +Generates a Spectrum TAP file for an emulator. +</p> + +The TAP file will be given the same name as the output filename, and its load +address will be set to the start of the created memory. If memory banks have +been used then each bank is output to the TAP file as separate code files. +</p> + +<p> +Remember that TAP files can be concatenated, so the output could be appended to +another TAP file containing a BASIC loader for example. +</p> +</td></tr> + +</table> + +</td></tr> + +</table> + +<h3>Listing</h3> + +<p> +By default no output listing is generated. This can be controlled by the +following options. +</p> + +<table> + +<thead><tr><td class="head">Listing Option</td> +<td class="head">Description</td></tr></thead> + +<tr><td class="cmd"> +option list, <on|off> +</td> +<td class="def"> +Enables or disables listing. The listing will go to stdout by default. +Defaults to <i>off</i>. +</td></tr> + +<tr><td class="cmd"> +option list-file, <i>filename</i> +</td> +<td class="def"> +Sends the listing to <i>filename</i>. Note this should appear before enabling +the listing. +</td></tr> + +<tr><td class="cmd"> +option list-pc, <on|off> +</td> +<td class="def"> +Control the output of the current PC in the as a comment preceding the +line (so that a listing could be reassembled with no editing). Defaults +to <i>off</i>. +</td></tr> + +<tr><td class="cmd"> +option list-hex, <on|off> +</td> +<td class="def"> +Control the output of the bytes generated by the source line in hex. +Defaults to <i>off</i>. If <i>on</i> then the hex is output in a comment +preceding the line (possibly with the PC above), so that a listing is still +valid as input to the assembler. +</td></tr> + +<tr><td class="cmd"> +option list-labels, <on|off|all> +</td> +<td class="def"> +Controls the listing of labels, either: + +<table> +<tr><td class="cmd"> +off +</td> +<td class="def"> +The default; don't list anything. +</td></tr> + +<tr><td class="cmd"> +on +</td> +<td class="def"> +List labels at the end of the listing. The labels are output commented so that +the list could be used as input. +</td></tr> + +<tr><td class="cmd"> +all +</td> +<td class="def"> +List all labels, including internally generated private labels for macros. +</td></tr> +</table> + +</td></tr> + +<tr><td class="cmd"> +option list-macros, <off|exec|dump|all> +</td> +<td class="def"> +Controls the listing of macro invocations, either: + +<table> +<tr><td class="cmd"> +off +</td> +<td class="def"> +The default; don't list anything. +</td></tr> + +<tr><td class="cmd"> +exec +</td> +<td class="def"> +List invocations of macros. +</td></tr> + +<tr><td class="cmd"> +dump +</td> +<td class="def"> +Produce a list of macro definitions at the end of the listing. +</td></tr> + +<tr><td class="cmd"> +all +</td> +<td class="def"> +Combine <i>exec</i> and <i>dump</i>. +</td></tr> +</table> +</td></tr> + +<tr><td class="cmd"> +option list-rm-blanks, <on|off> +</td> +<td class="def"> +Defaults to <i>on</i>. This option causes multiple blank lines to be collapsed +down to a single blank line in the listing. +</td></tr> +</table> + + +<h1>Z80 CPU</h1> + +<h2>Opcodes</h2> + +<p> +The Z80 assembler uses the standard Zilog opcodes, and supports +undocumented instructions. +</p> + +<p> +For instructions were the Accumulator can be assumed it can be omitted, and +EOR can be used the same as XOR: +</p> + +<pre class="codeblock"> + xor a,a ; These are equivalent + xor a + eor a,a + + and a,b ; These are equivalent + and b +</pre> + +<p> +For exchange opcodes with parameters the parameters can be reversed from their +official form: +</p> + +<pre class="codeblock"> + ; The official forms + ; + ex de,hl + ex af,af' + ex (sp),hl + ex (sp),ix + ex (sp),iy + + ; Also supported + ; + ex hl,de + ex af',af + ex hl,(sp) + ex ix,(sp) + ex iy,(sp) +</pre> + +<p> +Where the high/low register parts of the IX and IY registers are to be used, +simply use ixl, iyl, ixh and iyh. Note that the assembler will accept +illegal pairings involving H and L, but these will be warned about: +</p> + +<pre class="codeblock"> + ld ixh,$e5 + ld iyl,iyl + + ld ixh,l ; This will be turned into "ld ixh,ixl" and a + ; warning will be issued. + + ld iyh,ixl ; This will generate an error as the index registers + ; have been mixed. +</pre> + +<p> +For the hidden bit manipulations that also can copied to a register, these can +be represented by adding the destination register as an extra parameter, e.g. +</p> + +<pre class="codeblock"> + srl (iy-1),d + set 3,(iy-1),a + res 4,(iy-1),b +</pre> + +<p> +For the hidden IN instruction using the flag register the following are all +equivalent: +</p> + +<pre class="codeblock"> + in (c) + in f,(c) +</pre> + +<p> +For the hidden OUT instruction using the flag register, $00 or $ff depending +on where you're reading, the following are all equivalent, where _value_ can +be any value at all: +</p> + +<pre class="codeblock"> + out (c) + out (c),f + out (c),<value> +</pre> + + +<h2>Options</h2> + +The Z80 assembler has no options. + +<h1>6502 CPU</h1> + +<h2>Opcodes</h2> + +The 6502 assembler uses the standard Motorola opcodes. + + +<h2>Options</h2> + +The 6502 assembler has the following options. + +<table> + +<thead><tr><td class="head">6502 Option</td> +<td class="head">Description</td></tr></thead> + +<tr><td class="cmd"> +option zero-page, <on|off|auto> +</td> +<td class="def"> +Controls the assumptions made regarding Zero Page address. Defaults to +<i>off</i>, and can be the following values: + +<table> +<tr><td class="cmd"> +off +</td> +<td class="def"> +The default; all addresses are assumed to be not on the Zero Page, regardless +of the value used. +</td></tr> + +<tr><td class="cmd"> +on +</td> +<td class="def"> +Assumes all addresses are in the Zero Page, raising an error if any address is +not in the Zero Page. +</td></tr> + +<tr><td class="cmd"> +auto +</td> +<td class="def"> +Treats addresses less than 256 as being in the Zero Page automatically. This +mode also makes the assembler perform an extra pass to guard against the +possibility of the calculation being fooled. +</td></tr> +</table> + +e.g. + +<pre class="codeblock"> + cpu 6502 + org $8000 + + lda $0000,x ; Produces $bd $00 $00 + option +zero-page + lda $0000,x ; Produces $b5 $00 + lda $1234,x ; Produces an error + + option zero-page,auto + lda $00,x ; Produces $b5 $00 + lda $8000,x ; Produces $bd $00 $80 +</pre> + +</td></tr> +</table> + +<!-- vim: ai sw=4 ts=8 expandtab spell +--> +</body> +</html> diff --git a/doc/manual.asciidoc b/doc/manual.asciidoc deleted file mode 100644 index 3a20b69..0000000 --- a/doc/manual.asciidoc +++ /dev/null @@ -1,587 +0,0 @@ - -CASM -==== - -A simple, portable multi-pass assembler - -Copyright (C) 2003-2015 Ian Cowburn <ianc@noddybox.co.uk> - -This program is free software: you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation, either version 3 of the License, or -(at your option) any later version. - -This program is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. - -You should have received a copy of the GNU General Public License -along with this program. If not, see http://www.gnu.org/licenses/gpl-3.0.html - -Usage ------ - - ----- -casm file ----- - -Assembles file, and places the output in _output_ by default. - -Memory Layout -------------- - -There is 64K of RAM that the assembler will generate output into. Extra 64K -banks of RAM can be added by using the 'bank' or 'org' directives. Banks are -numbered from zero upwards. - - -Source Format Example ---------------------- - -The source files follow this basic format: - ----- -; Comments -; -label1: equ 0xffff - - org $4000; - - db "Hello, World\n",0 - -main jp local_label ; Comments - -.local_label - inc a - -another: - inc b - jp local_label ; Actually jumps to the following local_label. - -.local_label - ret ----- - - -The source files follow the following rules: - -* Any text past a semicolon (;) is discarded as a comment (except when part - of a string constant). - -* Labels must start in column zero (the left hand most column). - - ** If the label ends with a colon (:) then the colon is removed. - - ** If the label doesn't start with a period (.) then it is assumed a global - label. - - ** If the label starts with a period (.) then it is assumed to be a local - label. Local labels are associated with the preceding global label. If a - global label and related local label have the same name, the local label - will be used on expansion. - - ** Any label can be followed by an 'equ' directive, in which case the label - is set to that value rather than the current program counter. - - ** Labels are case-insensitive. - -* Directives and opcodes must appear further along the line (anywhere else - other than the left hand column where labels live basically). - -* Strings can either be quoted with single or double quotes; this allows you to - put the other quote type inside the string. - - -Recognised directives -~~~~~~~~~~~~~~~~~~~~~ - -All directives are also recognised with an optional period (.) in front of -them, and are case insensitive. Directives can also be used to control the -output of a program listing, and the output of the assembly itself. These are -documented in further sections. - - -processor _CPU_:: - Sets the processor type to _CPU_. If omitted then Z80 is the default. - Note that this can appear multiple times in the same file. Currently - supported _CPU_ values are +Z80+ and +6502+. - -option _setting_, _value_:: - Set options. Options are defined later on, and each CPU can also have its - own options. For options that support booleans (on/off/true/false), - the _setting_ can be prefixed with a plus or minus character to switch it - on or off respectively. - -equ _value_:: - Sets the top level label to _value_. Note this requires a label on the - same line. - -org _value_[,_bank_]:: - Sets the program counter (PC) to _value_. The PC defaults to zero. If the - optional second argument is passed the current memory bank in use is set - to _bank_. - -bank _value_:: - The current memory bank in use is set to _value_. - -ds _value_[, _fill_]:: - Skips on the program counter _value_ bytes. If the optional _fill_ is - provided then the bytes are filled with _fill_, otherwise they are filled - with zero. - -db _value_[, _value_]:: - Writes bytes to the current PC. The values can be constants, expressions, - labels or strings. Built-in aliases are +byte+ and +text+. - -dw <value>[, <value>]:: - Writes words (16-bit values) to the current PC. The values can be - constants, expressions or labels. Note that +word+ is a built-in alias for - this directive. - -align _value_[, _fill_]:: - Align the PC so that (PC modulus _value_) is zero. Will error if _value_ - is less than 2 or greater that 32768. No values are written to the skipped - bytes unless the optional _fill_ is supplied. - -include _filename_:: - Includes the source file _filename_ as if it was text entered at the - current location. - -incbin _filename_:: - Includes the binary data in _filename_ at the current PC, as if it was a - sequence of +db+ directives with all the bytes from the file. - -alias _command_, _replacement_:: - Creates an alias so that whenever the command _command_ is found in the - source it is replaced with _replacement_. The idea of this is to make it - easier to import sources that use unknown directives, e.g. - - alias setaddr,org - alias ldreg,ld - - cpu z80 - - setaddr $8000 ; These two are - org $8000 ; equivalent. - - ld a,(hl) ; These two are - ldreg a,(hl) ; equivalent. - -nullcmd:: - Simply does nothing. It's only real use is as an alias if you wished to - strip a directive from a foreign source file. - -end:: - Terminates the input processing. Anything past the directive will be - ignored. - - -Expressions -~~~~~~~~~~~ - -In any of the directives above, where a value is defined, an expression can be -entered. - -The following formats for constant numbers are supported (note these are -illustrated as a regular expression): - -"x" or 'x':: - A single quoted character will be converted into the appropriate character - code. - -[1-9][0-9]*:: - A decimal number, e.g. 42. - -0[0-7]*:: - An octal number, e.g. 052. - -0x[0-9a-fA-f]+:: - A hex number, e.g. 0x2a. - -[0-9a-fA-f]+h:: - A hex number, e.g. 2ah. - -$[0-9a-fA-f]+:: - A hex number, e.g. $2a. - -[01]+b:: - A binary number, e.g. 00101010b - -[a-zA-Z_0-9]+:: - A label, e.g. +main_loop+. - -The following operators are understood. The order here is the order of -precedence. - -{ }:: - Brackets used to alter the order of precedence. Note normal parenthesis - aren't used as the assembly language may make use of them. - -~ + -:: - Bitwise NOT/unary plus/unary minus. - -<< >>:: - Shift left/shift right. - -/ * %:: - Division/multiplication/modulus. - -+ -:: - Addition/subtraction. - -All the following have the same precedence, and so will be done left to right. - -==:: - Equality. Returns 1 if the arguments are equal, otherwise zero. - -!=:: - Inequality. Returns 1 if the arguments are unequal, otherwise zero. - -< \<= > >=:: - Less than/less than or equal/greater than/greater than or equal. Returns 1 - if the arguments are equal, otherwise zero. - - -All the following have the same precedence, and so will be done left to right. - -&& &:: - Boolean/bitwise AND. For boolean operation arguments, zero is FALSE, - otherwise TRUE. - -|| |:: - Boolean/bitwise OR. - -^:: - Bitwise XOR. - - -Assembly instructions will also permit these expressions to be used where -applicable. As many opcodes use parenthesis to indicate addressing modes, -remember that {} brackets can be used to alter expression precedence. - ----- - ld a,{8+2}*2 ; On the Z80 loads A with the value 20 - ld a,({8+2}*2) ; On the Z80 loads A with the value stored at - ; address 20 ----- - -Note that the expression is evaluated using a standard C int, and then cast -to the appropriate size. - - -Character Sets -~~~~~~~~~~~~~~ - -The assembler has built-in support for a few different character sets. -These can be set by using the options _charset_ or _codepage_, i.e. - ----- - option codepage, <format> - option charset, <format> ----- - -The following values can be used for _format_. - -ascii:: - 7-bit ASCII. This is the default. - -spectrum:: - The character codes as used on the Sinclair ZX Spectrum. - -zx81:: - The character codes as used on the Sinclair ZX-81. Lower case - letters are encoded as normal upper case letters and upper case - letter will be encoded as inverse upper case letters. - -cbm:: - PETSCII as used on the Commodore Business Machine's range from the - PET to the C128. See https://en.wikipedia.org/wiki/PETSCII for - more details. - -e.g. - ----- - option +list - option +list-hex - - option charset,ascii - db "Hello",'A' -; $48 $65 $6C $6C $6F $41 - - option charset,zx81 - db "Hello",'A' -; $AD $2A $31 $31 $34 $A6 - - option codepage,cbm - db "Hello",'A' -; $48 $45 $4C $4C $4F $41 - - option codepage,spectrum - db "Hello",'A' -; $48 $65 $6C $6C $6F $41 - ----- - - -Macros -~~~~~~ - -Macros can be defined in one of two ways; either parameterless or with named -parameters. Macro names are case-insensitive. In the parameterless mode the -special identifier '*' can be used to expand all arguments, which will be -separated with commas. - ----- -macro1: macro - - ld a,\1 - ld b,\2 - call \3 - defb \* - - endm - -macro2: macro char,junk,interface - - ld a,@char - ld b,@junk - call @interface - - endm ----- - -Note that trying to expand and unknown/missing argument will be replaced with -an empty string. Also the two argument reference styles can be mixed, though -obviously the @ form only makes sense in a parameterised macro, e.g. - ----- - -mac: macro char,junk,interface - - ld a,@char - ld b,\2 - call @interface - - endm ----- - -The at symbol (@) used for parameter expansion in named argument macros can -be replaced by using the following option, e.g. - ----- - option macro-arg-char,& ----- - -Note that this is enforced when the macro is *used*, not when it is *defined*. -Also the character must not be quoted, as that will be parsed as a string -holding the character code of the character. - - -Output Format -------------- - -By default the assembled code is written to a file called *output* as raw -binary covering the block of memory that the assembly touched. If memory -banks have been used then *output* is appended with the memory bank number, so -that a separate output file is generated for each bank. - -This can be controlled with the following options. - -option output-file, _file_:: - Send the output to _file_. If memory banks have been used then files are - generated with the names _file_.0, _file_.1, and so on. - -option output-type, _format_:: - Controls the output format with the following settings - - raw;; - The default raw binary. - - spectrum;; - Generates a Spectrum TAP file for an emulator. The TAP file will - be given the same name as the output filename, and its load address - will be set to the start of the created memory. Remember that TAP - files can be concatenated, so the output could be appended to - another TAP file containing a BASIC loader for example. Note that - if memory banks have been used then each bank is output to the TAP - file as separate code blocks. - - -Listing -------- - -By default no output listing is generated. This can be controlled by the -the following options. - -option list, <on|off>:: - Enables/disables listing. The listing will go to stdout. - -option list-file, _file_:: - Sends the listing to _file_. Note this should appear before enabling the - listing. - -option list-pc, <on|off>:: - Control the output of the current PC in the as a comment preceding the - line (so that a listing could be reassembled with no editing). Defaults - to *off*. - -option list-hex, <on|off>:: - Control the output of the bytes generated by the source line in hex. - Defaults to *off*. If *on* then the hex is output in a comment preceding - the line (possibly with the PC above), so that a listing is still valid to - be assembled. - -option list-labels, <on|off|all>:: - Controls the listing of labels, either *off* (the default), *on* to dump - label values at the end of the listing and *all* to dump all labels, - including internally generated private labels for macros. - -option list-macros, <off|exec|dump|all>:: - Controls the listing of macro invocations, either - - off;; - The default; don't list anything. - exec;; - List invocations of macros. - dump;; - Produce a list of macro definitions at the end of the listing. - all;; - Combine "exec" and "dump" - -option list-rm-blanks, <on|off>:: - Defaults to *on*. This option causes multiple blank lines to be collapsed - down to a single line. - - -Z80 CPU -------- - -Opcodes -~~~~~~~ - -The Z80 assembler uses the standard Zilog opcodes, and supports -undocumented instructions. - -For instructions were the Accumulator can be assumed it can be omitted, and -EOR can be used the same as XOR: - ----- - xor a,a ; These are equivalent - xor a - eor a,a - - and a,b ; These are equivalent - and b ----- - -For exchange opcodes with parameters the parameters can be reversed from their -official form: - ----- - ; The official forms - ; - ex de,hl - ex af,af' - ex (sp),hl - ex (sp),ix - ex (sp),iy - - ; Also supported - ; - ex hl,de - ex af',af - ex hl,(sp) - ex ix,(sp) - ex iy,(sp) ----- - -Where the high/low register parts of the IX and IY registers are to be used, -simply use ixl, iyl, ixh and iyh. Note that the assembler will accept -illegal pairings involving H and L, but these will be warned about: - ----- - - ld ixh,$e5 - ld iyl,iyl - - ld ixh,l ; This will be turned into "ld ixh,ixl" and a - ; warning will be issued. - - ld iyh,ixl ; This will generate an error as the index registers - ; have been mixed. - ----- - -For bit manipulations that also can copied to a register, these can be -represented by adding the destination register as an extra parameter, e.g. - ----- - - srl (iy-1),d - set 3,(iy-1),a - res 4,(iy-1),b - ----- - -For the hidden IN instruction using the flag register the following are all -equivalent: - ----- - in (c) - in f,(c) ----- - -For the hidden OUT instruction using the flag register, $00 or $ff depending -on where you're reading, the following are all equivalent, where _value_ can -be any value at all: - ----- - out (c) - out (c),f - out (c),<value> ----- - - -Options -~~~~~~~ - -The Z80 assembler has no options. - - -6502 CPU --------- - -Opcodes -~~~~~~~ - -The 6502 assembler uses the standard Motorola opcodes. - - -Options -~~~~~~~ - -The 6502 assembler has the following options. - -option zero-page, <on|off|auto>:: - Use Zero-Page addressing for _absolute_ and _absolute_,X address modes. - If mode is set to *auto* then tries to calculate the mode based on the - value in the last pass. - Defaults to *off*. e.g. - - cpu 6502 - org $8000 - - lda $0000,x ; Produces $bd $00 $00 - option +zero-page - lda $0000,x ; Produces $b5 $00 - lda $1234,x ; Produces an error - - option zero-page,auto - lda $00,x ; Produces $b5 $00 - lda $8000,x ; Produces $bd $00 $80 - - - -// vim: ai sw=4 ts=8 expandtab spell |