User manual

GHI Electronics,LLC Embedded Master User Manual
Hardware and Software Library
Notes:
• Current implementation supports multiple devices but only one USB Hub can be
detected. A USB Hub has a maximum of 7 devices. Therefore, a USB Hub and
seven USB devices can be used.
• Only supports one Interface per device (Several Interfaces might be present in a
device).
• Device Connection/Disconnection events are sent per device and each device has
a unique ID among the other connected devices.
• Self-Powered USB Hubs are highly recommended, Embedded Master and USBizi
are not designed to deliver power for multiple USB devices.
• Some USB Hubs are built as two separate USB Hubs internally. For example, one
USB Hub with seven ports is actually two Hubs inside. Therefore, Embedded
Master will only detect one USB Hub with few ports.
Embedded Master library has a built in event system to handle connection/disconnection
of devices. When a device is connected, an event is raised to the user and another event
for disconnection when the device is removed.
This event system is useful to dynamically check for the available devices. However, it is
not a requirement. The user can, at any time, retrieve a list of the available devices and
use some or all of them.
For an event driven system, the user registers to
GHIElectronics.System.SystemManager.SystemEvent event.
To use USB Host you must start it first using (need to be called once):
GHIElectronics.System.SystemManager.Start
After initialization, a list of current devices can be retrieved through
GHIElectronics.System.SystemManager.GetDevices
The list of devices is a GHIElectronics.System.SystemDevices.Device array. Each Device has a
type and a unique ID. The type is simply the type of the device (Mouse, Printer, ...) and the
ID is unique among the other current connected devices. The ID is useful if a user has two
similar devices and needs to distinguish them, for example, two mice but each with a
unique ID.
Example
Using the system with no events.
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