Based on USBKeyboardMouse example. I added USB String Descriptor so mbed reports itself to host not only with VID & PID but also with name of manufacturer, product name, serial number, configuration number and interface name. These can be changed to matching Yours in USBhid.cpp file on lines 88 - 122.

Dependencies:   mbed

Revision:
0:f97b1f255167
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/USBKeyboardMouse/USBKeyboard.h	Thu Sep 08 15:01:33 2011 +0000
@@ -0,0 +1,37 @@
+#include "usbhid.h"
+
+#ifndef MBED_USBKEYBOARD_H
+#define MBED_USBKEYBOARD_H
+
+/* Class: USBKeyboard
+ * Emulate a USB Keyboard HID device
+ *
+ * Example:
+ * > #include "mbed.h"
+ * > #include "USBKeyboard.h"
+ * > 
+ * > USBKeyboard kb;
+ * >
+ * > int main() {
+ * >     while(1) {
+ * >         kb.sendKeys("Foo goes here!");
+ * >         wait(2);
+ * >     }
+ * > }
+ */
+class USBKeyboard : private usbhid {
+public:
+    /* Constructor: USBKeyboard
+     * Create a USB Keyboard using the mbed USB Device interface
+     */
+    USBKeyboard();
+
+    void sendKeys(char *szString);
+    void sendKey(char c);
+    
+
+private:
+
+};
+
+#endif
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