A printhead assembly for an ink jet printer. A coordinate inputting apparatus includes a pen for transmitting an ultrasonic wave and a coordinate inputting apparatus for inputting coordinate positions of the pen based on a propagation time of the ultrasonic wave transmitted by the pen and received by a plurality of ultrasonic wave receivers. The flexible package offers manufacturing ease and cost-savings, and tamper-resistance. Otherwise, the holding client computer first attempts to downgrade its lock to meet the request, and if compatibility is not achieved thereby, the holding client refuses to relinquish the lock. The temperature sensor generates a temperature signal indicative of a head ambient temperature.