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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 |