Elixircom

A serial port terminal emulator for IEx.

This is useful if you are using Elixir projects that involve communicating with serial port devices that need a terminal like environment. Inspired by picocom.

To use it, add this project to your deps:

def deps do
  [
    {:elixircom, "~> 0.2.0"}
  ]
end

After building and starting a new IEx prompt, run:

iex> Elixircom.run("/dev/tty.usbmodem14103", speed: 115_200)

The name that you use will depend on your computer. This opens a serial port on OSX. To get a list of serial ports, run Circuits.UART.enumerate(). The speed parameter is optional. See Circuits.UART.open/3 for other options.

Here’s an example of how to connect to a Raspberry Pi Zero that’s running Nerves:

$ cd elixircom
$ iex -S mix
Erlang/OTP 21 [erts-10.0.8] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1] [hipe]

Interactive Elixir (1.7.3) - press Ctrl+C to exit (type h() ENTER for help)
iex> Circuits.UART.enumerate()
%{
  "/dev/cu.Bluetooth-Incoming-Port" => %{},
  "/dev/cu.MALS" => %{},
  "/dev/cu.SOC" => %{},
  "/dev/cu.usbmodem14103" => %{
    manufacturer: "Linux 4.14.71 with 20980000.usb",
    product_id: 42154,
    vendor_id: 1317
  }
}
iex> Elixircom.run("/dev/tty.usbmodem14103")

nil
iex(pi@pi.local)107>
nil
iex(pi@pi.local)108> 1 + 1
2
iex(pi@pi.local)109>

To exit out of the serial port terminal, press Ctrl+B.

iex> Elixircom.run("/dev/tty.usbmodem14103")

nil
iex(pi@pi.local)158>
nil
iex(pi@pi.local)159>
nil
iex(pi@pi.local)160> 1 + 1
2
iex(pi@pi.local)161> :ok
iex(2)>
nil
iex(3)>
nil
iex(4)>

Known Issues

Currently if you hit a runtime error when connecting to an IEx prompt over serial, for example a device running nerves, the next line waiting for input will be red along with the error message. To break the red coloring of the text just press enter/return.

We are waiting for a resolution on ERL-768 to fix this.