Abstract: A position detection circuit for detecting, by using a touch sensor, a position indicated by a passive pointer to a touch surface disposed on the touch sensor. The position detection circuit includes a detection circuit that detects a touch of the passive pointer to the touch surface, a calculation circuit that calculates a total value of capacitance values in a calculation region surrounding at least part of a touch region indicating a region of the touch, and an output circuit that outputs an indicated position that is indicated by the touch, based on the total value of the capacitance values. The output circuit outputs the indicated position when the total value is equal to or less than a threshold value, and does not output the indicated position or invalidates the indicated position and outputs the indicated position that has been invalidated, when the total value exceeds the threshold value.

Abstract: A wireless LAN access point communicates wirelessly with a wireless LAN communication terminal using an encryption key. The wireless LAN access point includes a proximate access point detecting section and an encryption key transmitting section. The proximate access point detecting section detects a proximate wireless LAN access point arranged at a short distance from the wireless LAN access point. The encryption key transmitting section transmits the encryption key to the proximate wireless LAN access point.