README

TinyGo - Go compiler for small places

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TinyGo is a Go compiler intended for use in small places such as microcontrollers, WebAssembly (Wasm), and command-line tools.

It reuses libraries used by the Go language tools alongside LLVM to provide an alternative way to compile programs written in the Go programming language.

Here is an example program that blinks the built-in LED when run directly on any supported board with onboard LED:

package main

import (
    "machine"
    "time"
)

func main() {
    led := machine.LED
    led.Configure(machine.PinConfig{Mode: machine.PinOutput})
    for {
        led.Low()
        time.Sleep(time.Millisecond * 1000)

        led.High()
        time.Sleep(time.Millisecond * 1000)
    }
}

The above program can be compiled and run without modification on an Arduino Uno, an Adafruit ItsyBitsy M0, or any of the supported boards that have a built-in LED, just by setting the correct TinyGo compiler target. For example, this compiles and flashes an Arduino Uno:

tinygo flash -target arduino examples/blinky1

Installation

See the getting started instructions for information on how to install TinyGo, as well as how to run the TinyGo compiler using our Docker container.

Supported boards/targets

You can compile TinyGo programs for microcontrollers, WebAssembly and Linux.

The following 62 microcontroller boards are currently supported:

For more information, see this list of boards. Pull requests for additional support are welcome!

Currently supported features:

For a description of currently supported Go language features, please see https://tinygo.org/lang-support/.

Documentation

Documentation is located on our web site at https://tinygo.org/.

You can find the web site code at https://github.com/tinygo-org/tinygo-site.

Getting help

If you're looking for a more interactive way to discuss TinyGo usage or development, we have a #TinyGo channel on the Gophers Slack.

If you need an invitation for the Gophers Slack, you can generate one here which should arrive fairly quickly (under 1 min): https://invite.slack.golangbridge.org

Contributing

Your contributions are welcome!

Please take a look at our CONTRIBUTING.md document for details.

Project Scope

Goals:

  • Have very small binary sizes. Don't pay for what you don't use.
  • Support for most common microcontroller boards.
  • Be usable on the web using WebAssembly.
  • Good CGo support, with no more overhead than a regular function call.
  • Support most standard library packages and compile most Go code without modification.

Non-goals:

  • Using more than one core.
  • Be efficient while using zillions of goroutines. However, good goroutine support is certainly a goal.
  • Be as fast as gc. However, LLVM will probably be better at optimizing certain things so TinyGo might actually turn out to be faster for number crunching.
  • Be able to compile every Go program out there.

Why this project exists

We never expected Go to be an embedded language and so its got serious problems...

-- Rob Pike, GopherCon 2014 Opening Keynote

TinyGo is a project to bring Go to microcontrollers and small systems with a single processor core. It is similar to emgo but a major difference is that we want to keep the Go memory model (which implies garbage collection of some sort). Another difference is that TinyGo uses LLVM internally instead of emitting C, which hopefully leads to smaller and more efficient code and certainly leads to more flexibility.

The original reasoning was: if Python can run on microcontrollers, then certainly Go should be able to run on even lower level micros.

License

This project is licensed under the BSD 3-clause license, just like the Go project itself.

Some code has been copied from the LLVM project and is therefore licensed under a variant of the Apache 2.0 license. This has been clearly indicated in the header of these files.

Some code has been copied and/or ported from Paul Stoffregen's Teensy libraries and is therefore licensed under PJRC's license. This has been clearly indicated in the header of these files.

Documentation

The Go Gopher

There is no documentation for this package.

Directories

Path Synopsis
Package builder is the compiler driver of TinyGo.
Package builder is the compiler driver of TinyGo.
Package cgo implements CGo by modifying a loaded AST.
Package cgo implements CGo by modifying a loaded AST.
Package compileopts contains the configuration for a single to-be-built binary.
Package compileopts contains the configuration for a single to-be-built binary.
ircheck
Package ircheck implements a checker for LLVM IR, that goes a bit further than the regular LLVM IR verifier.
Package ircheck implements a checker for LLVM IR, that goes a bit further than the regular LLVM IR verifier.
llvmutil
Package llvmutil contains utility functions used across multiple compiler packages.
Package llvmutil contains utility functions used across multiple compiler packages.
Package goenv returns environment variables that are used in various parts of the compiler.
Package goenv returns environment variables that are used in various parts of the compiler.
Package interp is a partial evaluator of code run at package init time.
Package interp is a partial evaluator of code run at package init time.
src
device/arm
CMSIS abstraction functions.
CMSIS abstraction functions.
examples/blinkm
Connects to an BlinkM I2C RGB LED.
Connects to an BlinkM I2C RGB LED.
examples/dac
Simplistic example using the DAC on the Circuit Playground Express.
Simplistic example using the DAC on the Circuit Playground Express.
examples/echo
This is a echo console running on the device UART.
This is a echo console running on the device UART.
examples/i2s
Example using the i2s hardware interface on the Adafruit Circuit Playground Express to read data from the onboard MEMS microphone.
Example using the i2s hardware interface on the Adafruit Circuit Playground Express to read data from the onboard MEMS microphone.
examples/mcp3008
Connects to an MCP3008 ADC via SPI.
Connects to an MCP3008 ADC via SPI.
examples/microbit-blink
blink program for the BBC micro:bit
blink program for the BBC micro:bit
os
Package os implements a subset of the Go "os" package.
Package os implements a subset of the Go "os" package.
runtime/debug
Package debug is a dummy package that is not yet implemented.
Package debug is a dummy package that is not yet implemented.
runtime/interrupt
Package interrupt provides access to hardware interrupts.
Package interrupt provides access to hardware interrupts.
runtime/volatile
Package volatile provides definitions for volatile loads and stores.
Package volatile provides definitions for volatile loads and stores.
testing
Package testing provides support for automated testing of Go packages.
Package testing provides support for automated testing of Go packages.
Package stacksize tries to determine the call graph for ELF binaries and tries to parse stack size information from DWARF call frame information.
Package stacksize tries to determine the call graph for ELF binaries and tries to parse stack size information from DWARF call frame information.
tests
tools
Package transform contains transformation passes for the TinyGo compiler.
Package transform contains transformation passes for the TinyGo compiler.