USB

All DUELink modules support USB. Some boards have a built-in USB connector; the rest use an adapter like USB Hook or USB Stick.

For first-time setup, see Get Started. This page covers the USB interface itself.

USB on DUELink modules is configured as the standard CDC class, so each module shows up as a virtual serial port on the connected host. No drivers are needed on modern Windows, macOS, Linux, or Android. Any of these can drive a Daisylink of modules using a host language.

USB is the first choice when using the Console and the Demo Website.

On Linux, you may need to grant your user permission to access the serial port — see the notes and example script on the UART interface page.

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Finding the port

Once plugged in, the module appears as:

• Windows: COMx (check Device Manager → Ports)
• macOS: /dev/cu.usbmodem...
• Linux: /dev/ttyACM0 (or similar)

Not sure which port belongs to your module? loader.duelink.com/discover queries everything on the bus and tells you what it finds.

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Keyboard and mouse emulation

Turn a DUELink module into a programmable keyboard or mouse — useful for automation and accessibility devices.

The USB connection is actually a composite device: CDC (virtual serial) for commands, plus HID (Human Interface Device) for keyboard and mouse reports. A connected computer or phone sees Serial, Keyboard, and Mouse devices on the same USB cable, regardless of OS.

The virtual serial side talks to the engine — same as every other interface. The HID side sends keystrokes and mouse movements via the Hid(type, [data]) function:

• type 1 = Keyboard
• type 2 = Mouse

The [data] array depends on which type you chose.

Mouse data:

Data	Use
Byte 0	Buttons (bitmask: Left=1, Right=2, Middle=4)
Byte 1-2	X movement (signed int16)
Byte 3-4	Y movement (signed int16)
Byte 5	Wheel (signed int8)
Byte 6	Pan (signed int8)

Keyboard data:

Data	Use
Byte 0	Modifier keys (e.g., Ctrl, Shift)
Byte 1	Reserved (always 0)
Bytes 2-7	Keycodes for up to 6 simultaneous key presses

Modifier key	Value
Left Ctrl	0x01
Left Shift	0x02
Left Alt	0x04
Left GUI (Win / Cmd)	0x08
Right Ctrl	0x10
Right Shift	0x20
Right Alt	0x40
Right GUI (Win / Cmd)	0x80

USB keyboard keycodes are listed in the USB HID Usage Tables and in community references like this gist.

For example, the codes for G, H, and I are 0x0A, 0x0B, and 0x0C respectively.

The example below reads touch pads on a DUELink module and sends their status as keyboard arrow-key presses. This script runs on the module itself via the Console:

Asio(1) # Enable Asynchronous Commands
dim b1[8] # keyboard need 8 bytes for one report
 
_p = 0 # press status
_s = 0 # backup status
 
while (1)
    if (TouchUp())
        b1[2] = 0x52
        _p = 1
    end
    if (TouchDown())
        b1[2] = 0x51
        _p = 1
    end
    if (TouchLeft())
        b1[2] = 0x50
        _p = 1
    end
    if (TouchRight())
        b1[2] = 0x4F
        _p = 1
    end
    if _p != _s
        if _p = 1
            hid(1,b1) # send key        
        else
            hid(1,[0,0,0,0,0,0,0,0]) # release    
        end
        _s = _p
    end
    _p = 0 # reset press status
wend