A Scheme subset for Atmel microcontrollers.
C MAXScript Assembly Scheme Makefile C++ Python
Latest commit c98938a May 19, 2016 @ryansuchocki Adding instruction to install avr-libc, which is optional dependency …
…of avr-gcc on some distros.

README.md

Microscheme

Microscheme is a Scheme subset designed for Atmel microcontrollers, especially as found on Arduino boards.

Recent Changes

  1. Microscheme now has apply!
  2. Microscheme now has an FFI!

Compiling

Quick-Start

$ make hexify

$ make build

$ ./microscheme examples/BLINK.ms

If you have an arduino on hand:

$ ./microscheme -m [MODEL] -d [/dev/WHATEVER] -auc examples/BLINK.ms

Detail

The microscheme source code is located in src/, and includes files written in C (.c, .h), assembly (.s) and in microscheme (.ms).

In order to compile microscheme, those source files written in assembly and microscheme are 'hexified', i.e. converted into C byte arrays by invoking $ make hexify. Next, the compiler is compiled by invoking $ make build.

The result is a standalone binary called 'microscheme' which is entirely self-contained, and can be separated from other files in this repository. On linux systems, invoke $ sudo make install to copy the binary to /usr/local/bin/, thus making it available system-wide.

Usage

As of the latest commit, the usage is:

Usage: microscheme [-auscvrio] [-m model] [-d device] [-p programmer] [-w filename] [-t rounds] program[.ms]

Option flags:
  -a    Assemble (implied by -u or -s) (requires -m)
  -u    Upload (requires -d)
  -s    Disassemble (to inspect final binary)
  -c    Cleanup (removes intermediate files)
  -v    Verbose
  -r    Verify (Uploading takes longer)
  -i    Allow the same file to be included more than once
  -o    Disable optimisations  
  -h    Show this help message 

Configuration flags:
  -m model       Specify a model (UNO/MEGA/LEO...)
  -d device      Specify a physical device
  -p programmer  Tell avrdude to use a particular programmer
  -w files       'Link' with external C or assembly files
  -t rounds      Specify the maximum number of tree-shaker rounds

Prerequisites

In order to compile microscheme, you will need some implementation of GCC and the unix utility XXD. (Readily available on Linux/OSX.)

In order to assemble programs and upload them to real Arduinos, you will need some implementation of avr-gcc, avr-libc and avrdude. Microscheme will try to invoke these tools directly, if the -a or -u options are used. Packages are available on all good linux distro's:

For example, on Arch linux:

$ sudo pacman -S avr-gcc avr-libc avrdude

Or, on Ubuntu or Debian:

$ sudo apt-get install gcc-avr avr-libc avrdude

These tools are available via the Homebrew and MacPorts package managers on Mac OS X and the winavr project on Windows.

Targets

Microscheme currently supports the ATMega168/328 (used on the Arduino UNO), the ATMega2560 (used on most Arduino MEGA boards), and the ATMega32u4. The target controller is set using the command line argument -m follwed by MEGA, UNO, or LEO (not required if you're just compiling).

Note: An Arduino Pro Mini with a 168/328 chip (programmed via an UNO board with its chip removed) can be treated as an UNO, because it uses the same chip.

Other chips can be supported by writing model definitions in models.c, containing values derived from the relevant Atmel datasheet.

Compiler pipeline

The entire compiler pipeline, as orchestrated by main.c, is:

[source code] → lexer.c → [token tree] → parser.c → [abstract syntax tree] → scoper.c → [(scoped) AST] → treeshaker.c → [(reduced) AST] → codegen.c → [assembly code] ...

If the -a (assemble) option is given:

[assembly code] → avr-gcc → [ELF binary] → avr-objcopy → [IHEX binary] ...

If the -u (upload) option is given:

[IHEX binary] → avrdude → Arduino Device

License

The MIT License (MIT)

Copyright (c) 2014 Ryan Suchocki

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.