mirror of
https://github.com/irmen/prog8.git
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Irmen de Jong
GitHub
commit
f20c4f98ac
@ -68,7 +68,7 @@ It contains all of the program's code and data and has a certain file format tha
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allows it to be loaded directly on the target system. Prog8 currently has no built-in
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support for programs that exceed 64 Kb of memory, nor for multi-part loaders.
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For the Commodore-64, most programs will have a tiny BASIC launcher that does a SYS into the generated machine code.
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For the Commodore 64, most programs will have a tiny BASIC launcher that does a SYS into the generated machine code.
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This way the user can load it as any other program and simply RUN it to start. (This is a regular ".prg" program).
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Prog8 can create those, but it is also possible to output plain binary programs
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that can be loaded into memory anywhere.
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@ -95,7 +95,7 @@ For normal use the compiler can be invoked with the command:
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By default, assembly code is generated and written to ``sourcefile.asm``.
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It is then (automatically) fed to the `64tass <https://sourceforge.net/projects/tass64/>`_ assembler tool
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that creastes the final runnable program.
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that creates the final runnable program.
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Command line options
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@ -182,7 +182,7 @@ One or more .p8 module files
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``-esa <address>``
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Override the base address of the evaluation stack. Has to be page-aligned.
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You can specify an integer or hexadecimal address.
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When not compiling for the CommanderX16 target, the location of the 16 virtual registers cx16.r0..r15
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When not compiling for the Commander X16 target, the location of the 16 virtual registers cx16.r0..r15
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is changed accordingly (to keep them in the same memory space as the evaluation stack).
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@ -15,7 +15,7 @@ This is a compiled programming language targeting the 8-bit
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`6510 <https://en.wikipedia.org/wiki/MOS_Technology_6510>`_ /
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`65c02 <https://en.wikipedia.org/wiki/MOS_Technology_65C02>`_ microprocessors.
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This CPU is from the late 1970's and early 1980's and was used in many home computers from that era,
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such as the `Commodore-64 <https://en.wikipedia.org/wiki/Commodore_64>`_.
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such as the `Commodore 64 <https://en.wikipedia.org/wiki/Commodore_64>`_.
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The language aims to provide many conveniences over raw assembly code (even when using a macro assembler),
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while still being low level enough to create high performance programs.
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You can compile programs for various machines with this CPU:
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@ -177,9 +177,9 @@ If you're scared of Oracle's licensing terms, most Linux distributions ship Open
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For Windows it's possible to get that as well; check out `AdoptOpenJDK <https://adoptopenjdk.net/>`_ .
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For MacOS you can use the Homebrew system to install a recent version of OpenJDK.
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Finally: an **emulator** (or a real machine ofcourse) to test and run your programs on.
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Finally: an **emulator** (or a real machine of course) to test and run your programs on.
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In C64 mode, the compiler assumes the presence of the `Vice emulator <http://vice-emu.sourceforge.net/>`_.
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If you're targeting the CommanderX16 instead, there's a choice of the official `x16emu <https://github.com/commanderx16/x16-emulator>`_
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If you're targeting the Commander X16 instead, there's a choice of the official `x16emu <https://github.com/commanderx16/x16-emulator>`_
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and the unofficial `box16 <https://github.com/indigodarkwolf/box16>`_ (you can select which one you want to launch
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using the ``-emu`` or ``-emu2`` command line options)
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@ -45,8 +45,8 @@ sys (part of syslib)
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system when the program is running.
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The following return values are currently defined:
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- 16 = compiled for CommanderX16 with 65C02 CPU
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- 64 = compiled for Commodore-64 with 6502/6510 CPU
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- 16 = compiled for Commander X16 with 65C02 CPU
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- 64 = compiled for Commodore 64 with 6502/6510 CPU
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``exit(returncode)``
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Immediately stops the program and exits it, with the returncode in the A register.
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@ -150,7 +150,7 @@ Provides string manipulation routines.
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``length(str) -> ubyte length``
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Number of bytes in the string. This value is determined during runtime and counts upto
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the first terminating 0 byte in the string, regardless of the size of the string during compilation time.
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Don't confuse this with ``len`` and ``sizeof``
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Don't confuse this with ``len`` and ``sizeof``!
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``left(source, length, target)``
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Copies the left side of the source string of the given length to target string.
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@ -176,8 +176,8 @@ Provides string manipulation routines.
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and the index in the string. Or 0+carry bit clear if the character was not found.
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``compare(string1, string2) -> ubyte result``
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Returns -1, 0 or 1 depeding on wether string1 sorts before, equal or after string2.
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Note that you can also directly compare strings and string values with eachother
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Returns -1, 0 or 1 depending on whether string1 sorts before, equal or after string2.
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Note that you can also directly compare strings and string values with each other
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using ``==``, ``<`` etcetera (it will use string.compare for you under water automatically).
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``copy(from, to) -> ubyte length``
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@ -283,7 +283,7 @@ Use the ``gfx2`` library if you want full-screen graphics or non-monochrome draw
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math
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----
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Low level integer math routines (which you usually don't have to bother with directly, but they are used by the compiler internally).
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Low-level integer math routines (which you usually don't have to bother with directly, but they are used by the compiler internally).
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Pseudo-Random number generators (byte and word).
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Various 8-bit integer trig functions that use lookup tables to quickly calculate sine and cosines.
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Usually a custom lookup table is the way to go if your application needs these,
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@ -337,7 +337,7 @@ and allows you to print it anywhere on the screen.
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prog8_lib
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---------
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Low level language support. You should not normally have to bother with this directly.
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Low-level language support. You should not normally have to bother with this directly.
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The compiler needs it for various built-in system routines.
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@ -356,7 +356,7 @@ Full-screen multicolor bitmap graphics routines, available on the Cx16 machine o
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palette (cx16 only)
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--------------------
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Available for the Cx16 target. Various routines to set the display color palette.
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There are also a few better looking Commodore-64 color palettes available here,
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There are also a few better looking Commodore 64 color palettes available here,
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because the Commander X16's default colors for this (the first 16 colors) are too saturated
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and are quite different than how they looked on a VIC-II chip in a C-64.
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@ -50,7 +50,7 @@ ROM routines
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------------
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#. provide a list of the core ROM routines on the system, with names, addresses, and call signatures.
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Ideally there are at least some routines to manipulate the screen and get some user input(clear, print text, print numbers, input strings from the keyboard)
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Ideally there are at least some routines to manipulate the screen and get some user input (clear, print text, print numbers, input strings from the keyboard)
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Routines to initialize the system to a sane state and to do a warm reset are useful too.
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The more the merrier.
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@ -74,7 +74,7 @@ the new target system.
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There are several other support libraries that you may want to port (``diskio``, ``graphics`` to name a few).
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Also ofcourse if there are unique things available on the new target system, don't hesitate to provide
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Also of course if there are unique things available on the new target system, don't hesitate to provide
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extensions to the ``syslib`` or perhaps a new special custom library altogether.
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@ -108,7 +108,7 @@ Be careful when importing other modules; blocks in your own code cannot have
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the same name as a block defined in an imported module or library.
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If you omit both the name and address, the entire block is *ignored* by the compiler (and a warning is displayed).
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This is a way to quickly "comment out" a piece of code that is unfinshed or may contain errors that you
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This is a way to quickly "comment out" a piece of code that is unfinished or may contain errors that you
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want to work on later, because the contents of the ignored block are not fully parsed either.
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The address can be used to place a block at a specific location in memory.
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@ -260,7 +260,7 @@ Floating point numbers
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^^^^^^^^^^^^^^^^^^^^^^
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Floats are stored in the 5-byte 'MFLPT' format that is used on CBM machines,
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and currently all floating point operations are specific to the Commodore-64.
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and currently all floating point operations are specific to the Commodore 64.
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This is because routines in the C-64 BASIC and KERNAL ROMs are used for that.
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So floating point operations will only work if the C-64 BASIC ROM (and KERNAL ROM)
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are banked in.
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@ -353,7 +353,7 @@ It can be correctly displayed on the screen only if a iso-8859-15 charset has be
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You can concatenate two string literals using '+', which can be useful to
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split long strings over separate lines. But remember that the length
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of the total string still cannot exceed 255 characaters.
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of the total string still cannot exceed 255 characters.
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A string literal can also be repeated a given number of times using '*', where the repeat number must be a constant value.
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And a new string value can be assigned to another string, but no bounds check is done
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so be sure the destination string is large enough to contain the new value (it is overwritten in memory)::
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@ -370,7 +370,7 @@ as newlines, quote characters themselves, and so on. The ones used most often ar
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``\\``, ``\"``, ``\n``, ``\r``. For a detailed description of all of them and what they mean,
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read the syntax reference on strings.
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Using the ``in`` operator you can easily check if a characater is present in a string,
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Using the ``in`` operator you can easily check if a character is present in a string,
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example: ``if '@' in email_address {....}`` (however this gives no clue about the location
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in the string where the character is present, if you need that, use the ``string.find()``
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library function instead)
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@ -412,10 +412,10 @@ for the constant itself). This is only valid for the simple numeric types (byte,
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When using ``&`` (the address-of operator but now applied to a datatype), the variable will point to specific location in memory,
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rather than being newly allocated. The initial value (mandatory) must be a valid
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memory address. Reading the variable will read the given data type from the
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address you specified, and setting the varible will directly modify that memory location(s)::
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address you specified, and setting the variable will directly modify that memory location(s)::
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const byte max_age = 2000 - 1974 ; max_age will be the constant value 26
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&word SCREENCOLORS = $d020 ; a 16-bit word at the addres $d020-$d021
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&word SCREENCOLORS = $d020 ; a 16-bit word at the address $d020-$d021
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.. _pointervars_programming:
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@ -511,7 +511,7 @@ Conditional Execution
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if statements
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^^^^^^^^^^^^^
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Conditional execution means that the flow of execution changes based on certiain conditions,
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Conditional execution means that the flow of execution changes based on certain conditions,
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rather than having fixed gotos or subroutine calls::
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if xx==5 {
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@ -567,7 +567,7 @@ So ``if_cc goto target`` will directly translate into the single CPU instruction
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.. caution::
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These special ``if_XX`` branching statements are only useful in certain specific situations where you are *certain*
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that the status register (still) contains the correct status bits.
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This is not always the case after a fuction call or other operations!
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This is not always the case after a function call or other operations!
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If in doubt, check the generated assembly code!
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.. note::
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@ -643,7 +643,7 @@ If possible, the expression is parsed and evaluated by the compiler itself at co
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Expressions that cannot be compile-time evaluated will result in code that calculates them at runtime.
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Expressions can contain procedure and function calls.
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There are various built-in functions such as sin(), cos() that can be used in expressions (see :ref:`builtinfunctions`).
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You can also reference idendifiers defined elsewhere in your code.
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You can also reference identifiers defined elsewhere in your code.
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Read the :ref:`syntaxreference` chapter for all details on the available operators and kinds of expressions you can write.
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@ -680,7 +680,7 @@ Logical expressions are expressions that calculate a boolean result: true or fal
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logical expressions will compile more efficiently than when you're using regular integer type operands
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(because these have to be converted to 0 or 1 every time)
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You can use parentheses to group parts of an expresion to change the precedence.
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You can use parentheses to group parts of an expression to change the precedence.
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Usually the normal precedence rules apply (``*`` goes before ``+`` etc.) but subexpressions
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within parentheses will be evaluated first. So ``(4 + 8) * 2`` is 24 and not 20,
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and ``(true or false) and false`` is false instead of true.
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@ -845,18 +845,18 @@ pokemon(address, value)
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Doesn't have anything to do with a certain video game.
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push(value)
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pushes a byte value on the CPU hardware stack. Lowlevel function that should normally not be used.
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pushes a byte value on the CPU hardware stack. Low-level function that should normally not be used.
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pushw(value)
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pushes a 16-bit word value on the CPU hardware stack. Lowlevel function that should normally not be used.
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pushes a 16-bit word value on the CPU hardware stack. Low-level function that should normally not be used.
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pop(variable)
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pops a byte value off the CPU hardware stack into the given variable. Only variables can be used.
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Lowlevel function that should normally not be used.
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Low-level function that should normally not be used.
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popw(value)
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pops a 16-bit word value off the CPU hardware stack into the given variable. Only variables can be used.
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Lowlevel function that should normally not be used.
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Low-level function that should normally not be used.
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rol(x)
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Rotate the bits in x (byte or word) one position to the left.
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@ -907,7 +907,7 @@ memory(name, size, alignment)
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You can only treat it as a pointer or use it in inline assembly.
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callfar(bank, address, argumentaddress) ; NOTE: specific to cx16 target for now
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Calls an assembly routine in another ram-bank on the CommanderX16 (using the ``jsrfar`` routine)
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Calls an assembly routine in another ram-bank on the Commander X16 (using the ``jsrfar`` routine)
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The banked RAM is located in the address range $A000-$BFFF (8 kilobyte), but you can specify
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any address in system ram (why this can be useful is explained at the end of this paragraph)
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The third argument can be used to designate the memory address
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@ -921,7 +921,7 @@ callfar(bank, address, argumentaddress) ; NOTE: specific to cx16 target for
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This is not very efficient though, so maybe you should write a small piece of inline assembly for this instead.
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callrom(bank, address, argumentaddress) ; NOTE: specific to cx16 target for now
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Calls an assembly routine in another rom-bank on the CommanderX16
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Calls an assembly routine in another rom-bank on the Commander X16
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The banked ROM is located in the address range $C000-$FFFF (16 kilobyte).
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There are 32 banks (0 to 31).
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The third argument can be used to designate the memory address
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@ -8,7 +8,7 @@ Module file
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-----------
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This is a file with the ``.p8`` suffix, containing *directives* and *code blocks*, described below.
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The file is a text file wich can also contain:
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The file is a text file which can also contain:
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Lines, whitespace, indentation
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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@ -48,7 +48,7 @@ Directives
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Global setting, selects the program launcher stub to use.
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Only relevant when using the ``prg`` output type. Defaults to ``basic``.
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- type ``basic`` : add a tiny C64 BASIC program, whith a SYS statement calling into the machine code
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- type ``basic`` : add a tiny C64 BASIC program, with a SYS statement calling into the machine code
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- type ``none`` : no launcher logic is added at all
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.. data:: %zeropage <style>
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@ -86,7 +86,7 @@ Directives
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The other options need those locations for other things so those virtual registers have
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to be put into memory elsewhere (outside of the zeropage). Trying to use them as zero page
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variables or pointers etc. will be a lot slower in those cases!
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On the CommanderX16 the registers are always in zeropage. On other targets, for now, they
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On the Commander X16 the registers are always in zeropage. On other targets, for now, they
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are always outside of the zeropage.
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.. data:: %zpreserved <fromaddress>,<toaddress>
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@ -119,7 +119,7 @@ Directives
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Sets special compiler options.
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- ``enable_floats`` (module level) tells the compiler
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to deal with floating point numbers (by using various subroutines from the Commodore-64 kernal).
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to deal with floating point numbers (by using various subroutines from the Commodore 64 kernal).
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Otherwise, floating point support is not enabled. Normally you don't have to use this yourself as
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importing the ``floats`` library is required anyway and that will enable it for you automatically.
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- ``no_sysinit`` (module level) which cause the resulting program to *not* include
|
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@ -150,7 +150,7 @@ Directives
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The assembler will include the file as raw assembly source text at this point,
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prog8 will not process this at all. Symbols defined in the included assembly can not be referenced
|
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from prog8 code. However they can be referenced from other assembly code if properly prefixed.
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You can ofcourse use a label in your prog8 code just before the %asminclude directive, and reference
|
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You can of course use a label in your prog8 code just before the %asminclude directive, and reference
|
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that particular label to get to (the start of) the included assembly.
|
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Be careful: you risk symbol redefinitions or duplications if you include a piece of
|
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assembly into a prog8 block that already defines symbols itself.
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@ -225,7 +225,7 @@ and after that, a combination of letters, numbers, or underscores. Examples of v
|
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Code blocks
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-----------
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||||
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A named block of actual program code. Itefines a *scope* (also known as 'namespace') and
|
||||
A named block of actual program code. It defines a *scope* (also known as 'namespace') and
|
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can only contain *directives*, *variable declarations*, *subroutines* or *inline assembly*::
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||||
|
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<blockname> [<address>] {
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@ -270,7 +270,7 @@ Variable declarations
|
||||
|
||||
Variables should be declared with their exact type and size so the compiler can allocate storage
|
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for them. You can give them an initial value as well. That value can be a simple literal value,
|
||||
or an expression. If you don't provide an intial value yourself, zero will be used.
|
||||
or an expression. If you don't provide an initial value yourself, zero will be used.
|
||||
You can add a ``@zp`` zeropage-tag, to tell the compiler to prioritize it
|
||||
when selecting variables to be put into zeropage (but no guarantees). If the ZP is full,
|
||||
the variable will be allocated in normal memory elsewhere.
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@ -505,7 +505,7 @@ logical: ``not`` ``and`` ``or`` ``xor``
|
||||
the ``bool`` variable type instead, where this conversion doesn't need to occur.
|
||||
|
||||
.. note::
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||||
Unlike most other programming languages, there is no short-cirquit or McCarthy-evaluation
|
||||
Unlike most other programming languages, there is no short-circuit or McCarthy evaluation
|
||||
for the logical ``and`` and ``or`` operators. This means that prog8 currently always evaluates
|
||||
all operands from these logical expressions, even when one of them already determines the outcome!
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@ -662,7 +662,7 @@ flag such as Carry (Pc).
|
||||
The 'virtual' 16-bit registers from the Commander X16 can also be specified as ``R0`` .. ``R15`` .
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||||
This means you don't have to set them up manually before calling a subroutine that takes
|
||||
one or more parameters in those 'registers'. You can just list the arguments directly.
|
||||
*This also works on the Commodore-64!* (however they are not as efficient there because they're not in zeropage)
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*This also works on the Commodore 64!* (however they are not as efficient there because they're not in zeropage)
|
||||
In prog8 and assembly code these 'registers' are directly accessible too via
|
||||
``cx16.r0`` .. ``cx16.r15`` (these are memory mapped uword values),
|
||||
``cx16.r0s`` .. ``cx16.r15s`` (these are memory mapped word values),
|
||||
@ -765,7 +765,7 @@ Conditional Execution and Jumps
|
||||
Unconditional jump: goto
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||||
^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
To jump to another part of the program, you use a ``goto`` statement with an addres or the name
|
||||
To jump to another part of the program, you use a ``goto`` statement with an address or the name
|
||||
of a label or subroutine::
|
||||
|
||||
goto $c000 ; address
|
||||
@ -806,7 +806,7 @@ However if <statements> is a block of multiple statements, you'll have to enclos
|
||||
**Special status register branch form:**
|
||||
|
||||
There is a special form of the if-statement that immediately translates into one of the 6502's branching instructions.
|
||||
It is almost the same as the regular if-statement but it lacks a contional expression part, because the if-statement
|
||||
It is almost the same as the regular if-statement but it lacks a conditional expression part, because the if-statement
|
||||
itself defines on what status register bit it should branch on::
|
||||
|
||||
if_XX <statements> [else <statements> ]
|
||||
@ -826,7 +826,7 @@ It can also be one of the four aliases that are easier to read: ``if_z``, ``if_n
|
||||
.. caution::
|
||||
These special ``if_XX`` branching statements are only useful in certain specific situations where you are *certain*
|
||||
that the status register (still) contains the correct status bits.
|
||||
This is not always the case after a fuction call or other operations!
|
||||
This is not always the case after a function call or other operations!
|
||||
If in doubt, check the generated assembly code!
|
||||
|
||||
|
||||
|
||||
@ -64,7 +64,7 @@ reserved address in use for
|
||||
================== =======================
|
||||
|
||||
The actual machine will often have many other special addresses as well,
|
||||
For example, the Commodore-64 has:
|
||||
For example, the Commodore 64 has:
|
||||
|
||||
- ROMs installed in the machine: BASIC, kernal and character roms. Occupying ``$a000``--``$bfff`` and ``$e000``--``$ffff``.
|
||||
- memory-mapped I/O registers, for the video and sound chips, and the CIA's. Occupying ``$d000``--``$dfff``.
|
||||
@ -80,7 +80,7 @@ ZeroPage ("ZP")
|
||||
|
||||
The ZeroPage memory block ``$02``--``$ff`` can be regarded as 254 CPU 'registers', because
|
||||
they take less clock cycles to access and need fewer instruction bytes than accessing other memory locations outside of the ZP.
|
||||
Theoretically they can all be used in a program, with the follwoing limitations:
|
||||
Theoretically they can all be used in a program, with the following limitations:
|
||||
|
||||
- several addresses (``$02``, ``$03``, ``$fb - $fc``, ``$fd - $fe``) are reserved for internal use
|
||||
- most other addresses will already be in use by the machine's operating system or kernal,
|
||||
@ -100,7 +100,7 @@ There's a global program directive to specify the way the compiler
|
||||
treats the ZP for the program. The default is to be reasonably restrictive to use the
|
||||
part of the ZP that is not used by the C64's kernal routines.
|
||||
It's possible to claim the whole ZP as well (by disabling the operating system or kernal).
|
||||
If you want, it's also possible to be more restricive and stay clear of the addresses used by BASIC routines too.
|
||||
If you want, it's also possible to be more restrictive and stay clear of the addresses used by BASIC routines too.
|
||||
This allows the program to exit cleanly back to a BASIC ready prompt - something that is not possible in the other modes.
|
||||
|
||||
|
||||
@ -163,5 +163,5 @@ The Commander X16 provides two additional routines that should be used *in your
|
||||
|
||||
cx16.push_vera_context()
|
||||
; ... do your work that uses vera here...
|
||||
cx15.pop_vera_context()
|
||||
cx16.pop_vera_context()
|
||||
|
||||
|
||||
@ -7,7 +7,7 @@ All variables are static in memory
|
||||
|
||||
All variables are allocated statically, there is no concept of dynamic heap or stack frames.
|
||||
Essentially all variables are global (but scoped) and can be accessed and modified anywhere,
|
||||
but care should be taken ofcourse to avoid unexpected side effects.
|
||||
but care should be taken of course to avoid unexpected side effects.
|
||||
|
||||
Especially when you're dealing with interrupts or re-entrant routines: don't modify variables
|
||||
that you not own or else you will break stuff.
|
||||
@ -42,7 +42,7 @@ Calling a subroutine requires three steps:
|
||||
|
||||
#. preparing the arguments (if any) and passing them to the routine
|
||||
#. calling the routine
|
||||
#. preparig the return value (if any) and returning that from the call.
|
||||
#. preparing the return value (if any) and returning that from the call.
|
||||
|
||||
|
||||
Calling the routine is just a simple JSR instruction, but the other two work like this:
|
||||
@ -83,7 +83,7 @@ Some builtin functions have a fully custom implementation.
|
||||
|
||||
|
||||
The compiler will warn about routines that are called and that return a value, if you're not
|
||||
doing something with that returnvalue. This can be on purpuse if you're simply not interested in it.
|
||||
doing something with that returnvalue. This can be on purpose if you're simply not interested in it.
|
||||
Use the ``void`` keyword in front of the subroutine call to get rid of the warning in that case.
|
||||
|
||||
|
||||
@ -138,7 +138,7 @@ Some notes and references into the compiler's source code modules:
|
||||
Most notably, node type information is now baked in. (``codeCore`` module)
|
||||
#. An *Intermediate Representation* has been defined that is generated from the intermediate AST. This IR
|
||||
is more or less a machine code language for a virtual machine - and indeed this is what the built-in
|
||||
prog8 VM will execute if you use the 'virtual' compilaton target and use ``-emu`` to launch the VM.
|
||||
prog8 VM will execute if you use the 'virtual' compilation target and use ``-emu`` to launch the VM.
|
||||
(``intermediate`` and ``codeGenIntermediate`` modules, and ``virtualmachine`` module for the VM related stuff)
|
||||
#. Currently the 6502 ASM code generator still works directly on the *Compiler AST*. A future version
|
||||
should replace this by working on the IR code, and should be much smaller and simpler.
|
||||
|
||||
Loading…
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Reference in New Issue
Block a user