Phal

Phal (Pokes Hardware And Listens) is a reusable component for end-to-end testing / remote control of embedded devices, written in Rust. The rough idea is to have peripherals of your device connected to another device running phal; you then get a configurable REST interface to .

Development Environment

If you use Nix, nix-shell should land you at a shell with everything you need.

Alternatively, you can manually install the prequisites:

• Rust, with Cargo and rustfmt
• Python 3, with the pytest and requests libraries (only for the end-to-end test)

Building

cargo build
cargo test

Usage

Do cargo run --release to start the server on port 8000. The server is configured by making HTTP POST requests to /config. The configuration file must be a JSON object, with members containing their own specific configuration. For example, the body of such a request could be:

{
  "my_first_limb": { ... },
  "limb_2": { ... },
  "another": { ... }
}

Each limb must be one of a few types, with their own configurations, these are:

Pin

A pin can either have type input-pin or output-pin, where it can either be read or written to, respectively.

To read an input pin called hello, make a GET request to /limb/hello.

To set the state of an output pin called something, make a POST request to /limb/something with either High or Low in the body.

{
  "gpio_10": {
      "type": "input-pin",
      "chip": "/dev/gpiochip0",
      "line": 10,
      "pin-type": "push-pull"
  },
  "gpio_13": {
      "type": "output-pin",
      "chip": "/dev/gpiochip0",
      "line": 13,
      "pin-type": "push-pull"
  }
}

Serial

To read from a serial interface called s, make a GET request to /limb/s. To write to it, POST to /limb/s with content in the request's body.

{
  "serial": {
    "type": "serial",
    "device": "/dev/ttyUSB0",
    "baud-rate": 9600,
    "char-size": 8,
    "parity": "none",
    "stop-bits": 1,
    "flow-control": "none"
  }
}

XMODEM

XMODEM limbs internally function identically to serial interfaces, but act as XMODEM transmitters instead of raw serial interfaces.

To send a file over an XMODEM interface make a POST request with the filename of the file to be transmitted. This must be a file on the remote host (the machine running PHAL).

Note: An XMODEM and Serial limb cannot both be configured for the same device.

{
  "my_xmodem": {
    "type": "xmodem",
    "device": "/dev/ttyUSB0",
    "baud-rate": 9600,
    "char-size": 8,
    "parity": "none",
    "stop-bits": 1,
    "flow-control": "none"
  }
}

Info

The configuration of the server can be queried by making GET requests to /info/types to return available limb types, and /info/limbs to return currently registered limbs, along with their type.

End-to-End Test

The self-test directory contains a Python test suite using phal to test itself. The intended set-up here is two Odroids XU4s with their UARTs connected, and lines connecting pins GPX2.0 on one to GPA2.6 on the other and vice versa. See Odroid XU4 GPIO for more information on using the XU4's GPIO pins.

Change the IP_A and IP_B constants in the python file to the IPs of your running test rigs. Then, running pytest in the directory should run a quick end-to-end test of the system.

Contributing

Please report bugs to the issue tracker and send patches to the phal-dev mailing list.