mirror of
https://github.com/irmen/prog8.git
synced 2024-11-23 07:32:10 +00:00
151 lines
6.4 KiB
Markdown
151 lines
6.4 KiB
Markdown
[](https://saythanks.io/to/irmen)
|
|
[](https://travis-ci.org/irmen/prog8)
|
|
[](https://prog8.readthedocs.io/)
|
|
|
|
Prog8 - Structured Programming Language for 8-bit 6502/65c02 microprocessors
|
|
============================================================================
|
|
|
|
*Written by Irmen de Jong (irmen@razorvine.net)*
|
|
|
|
*Software license: GNU GPL 3.0, see file LICENSE*
|
|
|
|
|
|
This is a structured programming language for the 8-bit 6502/6510/65c02 microprocessor from the late 1970's and 1980's
|
|
as used in many home computers from that era. It is a medium to low level programming language,
|
|
which aims to provide many conveniences over raw assembly code (even when using a macro assembler).
|
|
|
|
Documentation
|
|
-------------
|
|
Full documentation (syntax reference, how to use the language and the compiler, etc.) can be found at:
|
|
https://prog8.readthedocs.io/
|
|
|
|
|
|
What does Prog8 provide?
|
|
------------------------
|
|
|
|
- reduction of source code length over raw assembly
|
|
- fast execution speed due to compilation to native assembly code. It's possible to write certain raster interrupt 'demoscene' effects purely in Prog8.
|
|
- modularity, symbol scoping, subroutines
|
|
- various data types other than just bytes (16-bit words, floats, strings)
|
|
- automatic static variable allocations, automatic string and array variables and string sharing
|
|
- subroutines with input parameters and result values
|
|
- high-level program optimizations
|
|
- small program boilerplate/compilersupport overhead
|
|
- Programs can be run multiple times without reloading because of automatic variable (re)initializations.
|
|
- conditional branches
|
|
- floating point operations (requires the C64 Basic ROM routines for this)
|
|
- 'when' statement to provide a concise jump table alternative to if/elseif chains
|
|
- structs to group together sets of variables and manipulate them at once
|
|
- many built-in functions such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``sort`` and ``reverse``
|
|
- various powerful built-in libraries to do I/O, number conversions, graphics and more
|
|
- convenience abstractions for low level aspects such as ZeroPage handling, program startup, explicit memory addresses
|
|
- inline assembly allows you to have full control when every cycle or byte matters
|
|
- supports the sixteen 'virtual' 16-bit registers R0 .. R15 from the Commander X16, and provides them also on the C64.
|
|
- encode strings and characters into petscii or screencodes as desired (C64/Cx16)
|
|
|
|
*Rapid edit-compile-run-debug cycle:*
|
|
|
|
- use a modern PC to do the work on, use nice editors and enjoy quick compilation times
|
|
- can automatically run the program in the Vice emulator after succesful compilation
|
|
- breakpoints, that let the Vice emulator drop into the monitor if execution hits them
|
|
- source code labels automatically loaded in Vice emulator so it can show them in disassembly
|
|
|
|
*Two supported compiler targets* (contributions to improve these or to add support for other machines are welcome!):
|
|
|
|
- "c64": Commodore-64 (6510 CPU = almost a 6502)
|
|
- "cx16": [CommanderX16](https://www.commanderx16.com) (65c02 CPU)
|
|
- If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for both machines (just change the compiler target flag)!
|
|
|
|
|
|
|
|
Additional required tools
|
|
-------------------------
|
|
|
|
[64tass](https://sourceforge.net/projects/tass64/) - cross assembler. Install this on your shell path.
|
|
A recent .exe version of this tool for Windows can be obtained from my [clone](https://github.com/irmen/64tass/releases) of this project.
|
|
For other platforms it is very easy to compile it yourself (make ; make install).
|
|
|
|
A **Java runtime (jre or jdk), version 11 or newer** is required to run a prepackaged version of the compiler.
|
|
If you want to build it from source, you'll need a Java SDK + Kotlin 1.3.x SDK (or for instance,
|
|
IntelliJ IDEA with the Kotlin plugin).
|
|
|
|
It's handy to have an emulator (or a real machine perhaps!) to run the programs on. The compiler assumes the presence
|
|
of the [Vice emulator](http://vice-emu.sourceforge.net/) for the C64 target,
|
|
and the [x16emu emulator](https://github.com/commanderx16/x16-emulator) for the CommanderX16 target.
|
|
|
|
|
|
Example code
|
|
------------
|
|
|
|
This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
|
|
|
|
%import textio
|
|
%zeropage basicsafe
|
|
|
|
main {
|
|
|
|
ubyte[256] sieve
|
|
ubyte candidate_prime = 2 ; is increased in the loop
|
|
|
|
sub start() {
|
|
sys.memset(sieve, 256, false) ; clear the sieve
|
|
txt.print("prime numbers up to 255:\n\n")
|
|
ubyte amount=0
|
|
repeat {
|
|
ubyte prime = find_next_prime()
|
|
if prime==0
|
|
break
|
|
txt.print_ub(prime)
|
|
txt.print(", ")
|
|
amount++
|
|
}
|
|
txt.nl()
|
|
txt.print("number of primes (expected 54): ")
|
|
txt.print_ub(amount)
|
|
txt.nl()
|
|
}
|
|
|
|
sub find_next_prime() -> ubyte {
|
|
while sieve[candidate_prime] {
|
|
candidate_prime++
|
|
if candidate_prime==0
|
|
return 0 ; we wrapped; no more primes
|
|
}
|
|
|
|
; found next one, mark the multiples and return it.
|
|
sieve[candidate_prime] = true
|
|
uword multiple = candidate_prime
|
|
|
|
while multiple < len(sieve) {
|
|
sieve[lsb(multiple)] = true
|
|
multiple += candidate_prime
|
|
}
|
|
return candidate_prime
|
|
}
|
|
}
|
|
|
|
|
|
|
|
|
|
when compiled an ran on a C-64 you'll get:
|
|
|
|
|
|
|
|
One of the included examples (wizzine.p8) animates a bunch of sprite balloons and looks like this:
|
|
|
|
|
|
|
|
Another example (cube3d-sprites.p8) draws the vertices of a rotating 3d cube:
|
|
|
|
|
|
|
|
If you want to play a video game, a fully working Tetris clone is included in the examples:
|
|
|
|
|
|
|
|
There are a couple of examples specially made for the CommanderX16 compiler target.
|
|
For instance here's a well known space ship animated in 3D with hidden line removal,
|
|
in the CommanderX16 emulator:
|
|
|
|
|