Abstract: A wireless presentation system includes a first wireless input element, a second wireless input element and a wireless receiving and processing host. A pairing method for use in the wireless presentation system includes the following steps. The wireless receiving and processing host generates a first identification code, and if the first wireless input element is present, issues the first identification code to the first wireless input element for storage, so that a pairing relation therebetween is established by the first identification code. The wireless receiving and processing host automatically generates a second identification code after the first identification code is issued, and if the second wireless input element is present, issues the second identification code to the second wireless input element for storage, so that the pairing relation therebetween is established by the second identification code.

Abstract: A power supply topology with pulse width modulation frequency control allows the use of an inductor with higher inductance in a converter. By controlling the switching frequency of the pulse width modulation signal, the inductor can achieve high efficiency during a light load condition and is also suitable for a heavy load condition.

Abstract: A cursor control device includes a pen-like body, a motion-detecting element, a microcontroller and a button element. The motion-detecting element is disposed at a first side of the pen-like body for generating a coordinate change signal in response to a motion of a first finger of the user. The microcontroller is disposed within the pen-like body and communicated with the motion-detecting element and the computer system. According to the coordinate change signal, the microcontroller issues a cursor control signal to the computer system. The button element is disposed at a second side of the pen-like body and communicated with the microcontroller for triggering the microcontroller to generate an object locking control signal in response to a depressing action of a second finger of the user. The object pointed by the cursor is locked according to the object locking control signal and moved according to the cursor control signal.

Abstract: A wireless presentation system includes a first wireless input element, a second wireless input element and a wireless receiving and processing host. A pairing method for use in the wireless presentation system includes the following steps. The wireless receiving and processing host generates a first identification code, and if the first wireless input element is present, issues the first identification code to the first wireless input element for storage, so that a pairing relation therebetween is established by the first identification code. The wireless receiving and processing host automatically generates a second identification code after the first identification code is issued, and if the second wireless input element is present, issues the second identification code to the second wireless input element for storage, so that the pairing relation therebetween is established by the second identification code.

Abstract: A power supply topology with pulse width modulation frequency control allows the use of an inductor with higher inductance in a converter. By controlling the switching frequency of the pulse width modulation signal, the inductor can achieve high efficiency during a light load condition and is also suitable for a heavy load condition.

Abstract: A system and method for the transfer of media content from an Internet server to a portable device is disclosed which may be configured using currently existing WAP and Internet server technologies with a new file downloading mechanism called Internal Code Control which makes use of Multipurpose Internet Mail Extension types and file segmentation techniques to facilitate file transfer and download verification. An Index Parsing method of the Internal Code Control mechanism is disclosed for facilitating content download and billing functions.