libusb-pharo

This project provides binding to the libusb library for Pharo. We currently target Pharo 7.

Install

Execute the following code snippet to install the package:

Metacello new
    repository: 'github://tamerescrl/libusb-pharo/repository';
    baseline: 'LibUsb';
    load

Quickstart

Listing all the connected USB devices

LUContext withAllDevicesDo: [ :context :devices | "Play with devices..." ]

Get a lsusb like output for a device printed in Transcript

LUContext withAllDevicesDo: [ :context :devices |
    | ps3Controller |
    context logLevelDebug.
    "Searching the ps3 controller using its vendor id and product id."
    ps3Controller := devices detect: [ :dev |
                            dev idVendor = 16r054c
                                and: [ dev idProduct = 16r0268 ] ].
    Transcript
        show: 'Bus ';
        show: (ps3Controller busNumber printPaddedWith: $0 to: 3 base: 10);
        show: ' Device ';
        show: (ps3Controller address printPaddedWith: $0 to: 3 base: 10);
        show: ': ID ';
        show: (ps3Controller idVendor printPaddedWith: $0 to: 4 base: 16);
        show: ':';
        show: (ps3Controller idProduct printPaddedWith: $0 to: 4 base: 16);
        space;
        show: ps3Controller manufacturerDescription;
        show: ps3Controller productDescription; cr ]

HID layer

This repository also holds an implementation of the Human Interface Device protocol with a driver to be used with libusb binding.

Install

Execute the following code snippet to install the package:

Metacello new
    repository: 'github://tamerescrl/libusb-pharo/repository';
    baseline: 'HumanInterfaceDevice';
    load

You are now ready to use this project!

Only install the packages you need

It is also possible to install only the packages you need. For example, you may want to use the libusb-backend with the core package only. To be able to do that, the baseline defines groups:

• 'core': contains only the HumanDeviceInterface package, nothing else.
• 'libusb-backend': contains the core package and the libusb backend.
• 'simulated-backend': contains the core package and the simulated backend (for learning/testing purpose).

If you do not specify a particular group, all packages are loaded including tests packages (this is useful for development).

To load a group (for example 'core'), simply pass the string representing the package name to #load: message as follow:

Metacello new
    repository: 'github://tamerescrl/libusb-pharo/repository';
    baseline: 'HumanInterfaceDevice';
    load: 'core'.

Quick start

The following code gives you hints on how to use the HID layer.

If you use linux, the following command is probably available on your system:

$ lsusb

It will print the following output that shows multiple information about the usb devices connected to the system. For the example we will take the vid:pid of the Linux Foundation 2.0 root hub (046d:c52f).

Bus 004 Device 003: ID 045e:07a5 Microsoft Corp. Wireless Receiver 1461C
Bus 004 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 002: ID 046d:c52f Logitech, Inc. Unifying Receiver
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 004: ID 058f:6366 Alcor Micro Corp. Multi Flash Reader
Bus 001 Device 003: ID 05c8:030d Cheng Uei Precision Industry Co., Ltd (Foxlink) 
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
                       ^    ^
                       vid  pid

Do not forget to replace vid and pid by those from your usb device in the following code:

backend := HIDLibusbBackend vid: 16r046d pid: 16rc52f.

backend open.
backend takeDeviceControl.

"Get the report descriptor from the device or returns the one in cache if it has already be done."
reportDescriptor := backend reportDescriptor.

backend releaseDeviceControl.
backend close.