The invention relates to a portable wireless anti-theft flash memory having a body proper in which there are a flash memory, a high frequency receiver circuit, and a monode switch to go with a cap, in which are a high frequency transmitter, an encoding circuit, and a counter, for casing the body proper. These test cells are connected in parallel respectively to the p outputs of the logic unit such that the logic values of the outputs of the logic unit are loaded into the test cells in a normal mode, and are connected in series with each other to form a shift register for propagating logic values of the outputs of the logic unit to a collecting node in a test mode. While ascertaining the contents of the files in a predetermined folder and comparing among the files with the icons displayed as thumbnails in the file display window W1, the user can select files to be processed by double-clicking. The wavelength adjusting step changes DBR current injected into the DBR region and phase current injected into the phase region based on the relationship. In this manner, a user can rotate the side plates and inner support plates parallel to the upper plates and the lower plate causing a collapsed configuration that provides for easy storage and shipping. Each state is characterized by assigning a single node as the data-generating node, and configuring all other nodes in the network as repeaters and receivers.