#sdl2 #arm #monotron

monotron-app

Support crate for writing Monotron applications

1 unstable release

Uses old Rust 2015

0.5.0 May 5, 2019

#1140 in Embedded development

24 downloads per month

Custom license

32KB
816 lines

Monotron Application Binary Interface

This crate allows you to write applications for the Monotron. Think of this like the Linux kernel syscall ABI, or the MS-DOS programming API, but designed for applications written in Rust, better suited to a system with very few resources and not as well developed.

The crate provides a entry pointer of the format:

pub static ENTRY_POINT: fn(*const Table, *mut Context) -> i32 = entry_point;

This pointer is placed at the bottom of the memory address range reserved for applications (0x2000_2000). Monotron will jump to the function pointed to by this pointer at application start time, and pass in a structure full of callback pointers. These pointers can be used by the application to call various OS functions. This crate wraps all that up into a Host object, on which the application can call methods, e.g.:

Host::puts(b"Hello, world!");

If you compile for a non bare-metal target, you get an SDL2 window which contains a pixel perfect rendering of the Monotron screen. Be aware though that the screen only updates if you call wfvbi(), so do that in your main loop.

This crate compiles as a static library which you can also link against C applications if you prefer to use C instead of Rust - see monotron.h for the C compatible declarations.

Dependencies

~18MB
~393K SLoC