Component: USB HID (Comms: USB)

Author	Matrix Ltd
Version	1.4
Category	Comms: USB

USB HID component

Component to create and communicate using a standard HID type USB class. Compatible with simulation and USB enabled microcontroller devices PIC/dsPIC/AVR. Note that AVR is currently in Beta and may have problems with custom descriptors.

Component Source Code

Please click here to download the component source project: FC_Comp_Source_USBHID.fcfx

Please click here to view the component source code (Beta): FC_Comp_Source_USBHID.fcfx

Detailed description

No detailed description exists yet for this component

Examples

Here are some examples to get you started with USB HID communications using Flowcode.

HID Mouse

Reads a EB014 keypad and depending on the key pressed sends the appropriate movement and button clicks to control the mouse.

The speed is set by the speed variable which can range from 1 to 127.

Mouse Keypad Example

Key breakdown: 1 = UpLeft, 2=Up, 3=UpRight, 4=Left, 6=Right, 7=DownLeft, 8=Down, 9=DownRight, *=Left Click, #=Right Click.

Reads two encoders and moves the mouse cursor based on their movement since the last operation.

A switch on pin B0 can be used to toggle the left mouse click on and off and pin B1 can be connected to an LED to show the status of the left mouse button.

The EB073 encoders board connected to PortB will allow all of this functionality.

Mouse Encoder Example

HID Keyboard

Converts a ASCII character into a keypress that will be sent to the USB host device.

A demo string is provided which is then broken down into characters and sent to the USB host.

Keyboard Example

Here is a file showing the standard HID keyboard scan codes to help make sense of the example.

File:HID Keyboard Scan Codes.xls

With the example running if you create a text file and highlight the text file then the USB device will populate the file with data.

E.g.

HelloFromYourUSBKeyboardDevice12345

HelloFromYourUSBKeyboardDevice12345

HelloFromYourUSBKeyboardDevice12345

Currently only compatible with the following characters: 0123456789!"£$%^&*()/\*-+ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz\n\t

A complete list of keyboard scan codes can be found here under section 7 - Keyboards.

http://www.freebsddiary.org/APC/usb_hid_usages.php

HID Descriptor Tool

This tool allows you to create your own descriptors which can then be inserted into the HID descriptor property with the custom descriptor type selected.

File:HID Descriptor Tool.zip

Macro reference

	ReceiveByte
Receives a byte from the USB.
- BYTE	Idx
- BYTE	Return

	SetSerialNumber
Allows the device serial number to be edited.
- STRING	SerialNumber
- VOID	Return

	SendData
Sends the contents of the transmit buffer to the USB.
- BYTE	Return

	CheckRx
Checks for any incoming data. Returns the number of data bytes received since the last check.
- BYTE	Return

	UpdateData
Allows a byte of the transmit buffer to be assigned.
- BYTE	idx
- BYTE	value
- VOID	Return

	ReceiveString
Receives a string of bytes from the USB
- BYTE	NumBytes
- STRING	Return

	SendDataDirect
Sends data directly to the USB
- STRING	Data
- BYTE	Return

	Initialise
Starts up the USB connection and waits for the device driver to be correctly installed on the PC.
- BYTE	Return

Property reference

	Properties
	USB Properties
	Vendor ID
USB vendor identifier tied to the manufacturer of the USB device
	Product ID
USB product identifier
	Device Name
Name used to identify the device
	Manufacturer
Manufacturer of the device
	Major Version
Firmware major version
	Minor Version
Device firmware minor version
	Enumeration Timeout
Specifies if the initialise routine is allowed to timeout instead of waiting forever for success
	Maximum Current (mA)
Maximum current the host should source to the device - max 500mA
	Country Code
Specific country code - if required
	Descriptor Select
Built in descriptor selection
	HID Descriptor
Contents of the HID descriptor
	Subclass
USB Subclass - Normally only mice and keyboards are boot devices
	Interface
Standard HID interface type
	Transmit Packet Size
Number of bytes to send to the PC
	Transmit Period (ms)
Delay between transmit packets
	Receive Packet Size
Number of bytes to receive from the PC
	Receive Period (ms)
Delay between receive packets
	Simulation
	Label
Simulation label used to indicate the USB HID component on the panel.