GRiSP Mix plug-in

Mix plug-in to build and deploy GRiSP applications for the GRiSP board.

Summary

The package can be installed by adding mix_grisp to your list of dependencies in mix.exs:

def deps do
  [
    {:mix_grisp, "~> 0.2.0", only: :dev}
  ]
end

New Project Step-By-Step

Create New Project

Create a project using Elixir default project template:

```
$ mix new testex --module TestEx
$ cd testex
```

Add Dependencies

Add the following dependencies in the project configuration mix.exs:

```
    defp deps do
        [
            ...
            {:grisp, "~> 2.4"},
            {:mix_grisp, "~> 0.2.0", only: :dev},
        ]
    end
```

Configure Grisp

Add the following configuration to your project configuration mix.exs:

```
    def project do
        [
            ...
            grisp: grisp(),
            releases: releases()
        ]
    end

    def grisp do
        [
            otp: [version: "27"],
            deploy: [
                # pre_script: "rm -rf /Volumes/GRISP/*",
                # destination: "tmp/grisp"
                # post_script: "diskutil unmount /Volumes/GRISP",
            ]
        ]
    end

    def releases do
        [
            {:myapp,
                [
                    overwrite: true,
                    cookie: "grisp",
                    include_erts: &MixGrisp.Release.erts/0,
                    steps: [&MixGrisp.Release.init/1, :assemble],
                    include_executables_for: [],
                    strip_beams: Mix.env() == :prod
                ]}
            ]
    end
```

You can uncomment the lines in the deploy list after setting the proper mount point for your SD card if you want to deploy directly to it. The destination can be a normal path if you want to deploy to a local directory.

Add the following boot configuration files after changing GRISP_HOSTNAME to the hostname you want the grisp board to have, WLAN_SSID and WLAN_PASSWORD to the ssid and password of the WiFi network the Grisp board should connect to.

* `grisp/grisp2/common/deploy/files/grisp.ini.mustache`

    ```
    [erlang]
    args = erl.rtems -C multi_time_warp -- -mode embedded -home . -pa . -root {{release_name}} -bindir {{release_name}}/erts-{{erts_vsn}}/bin -boot {{release_name}}/releases/{{release_version}}/start -boot_var RELEASE_LIB {{release_name}}/lib  -config {{release_name}}/releases/{{release_version}}/sys.config -s elixir start_iex -extra --no-halt
    shell = none

    [network]
    ip_self=dhcp
    wlan=enable
    hostname=GRISP_HOSTNAME
    wpa=wpa_supplicant.conf
    ```


* `grisp/grisp2/common/deploy/files/wpa_supplicant.conf`

    ```
    network={
        ssid="WLAN_SSID"
        key_mgmt=WPA-PSK
        psk="WLAN_PASSWORD"
    }
    ```

Add Configuration

If not generated bu Mix template, add the file config/config.exs:

```
import Config
```

Check OTP Version

Verify that your default erlang version matches the one configured (26 in the example).

This is required because the beam files are compiled locally and need to be compiled by the same version of the VM.

Get Dependencies

Get all the dependencies:

```
$ mix deps.get
```

Deploy The Project

To deploy, use the grisp command provided by mix_grisp:

```
$ mix grisp.deploy
```

Troubleshooting

This BEAM file was compiled for a later version of the run-time system

Some bema files were compiled with a newer version of OTP, delete _build and deps, get the fresh dependencies (mix deps.get), and redeploy (mix grisp.deploy).

Enabling Erlang Distribution

1. Add the erlang epmd to your release to be able to run Erlang distribution on GRiSP

   1. Add the following line in your deps, this will ship epmd without starting it at boot.

      {:epmd, git: "https://github.com/erlang/epmd", ref: "4d1a59", runtime: false},

   2. Add epmd to the included applications so its modules are loaded at runtime

       def application do
        [
          extra_applications: [:logger],
          included_applications: [:epmd]
        ]
      end

2. Read the GRiSP.ini chapter of the wiki

3. Your grisp.ini.mustache file args should terminate with the following flags, choose a nodename and cookie of your liking.

   ... -s elixir start_iex -kernel inetrc "./erl_inetrc" -internal_epmd epmd_sup -sname mynode -setcookie mycookie -extra --no-halt