Existing pressure sensing fabrics may involve two portions, i. A user has a personal card with a code, the code identifying the user to the cash register and being related to a user ID. The present invention provides an algorithm engine which searches to determine whether the incoming phone number is in a format recognized by the network, and if not formats the phone number in the correct format for the PCS device for display thereon. The modulator circuit also comprises a feedforward structure that determines an approximated duty cycle for the pulse signal based on the value of the input voltage, the sensed output voltage and the amount of current flow in the inductor. If a pool is too large or too small, or if a pool’s rate of growth is too large or too small, the central computer sends a message to all terminals which contribute to the pool, causing the terminals to modify operations so as to bring the pool size or rate of growth to within desired target ranges.