Patent ID: 7187924

Claim:
A method for implementing two-way communication between at least first and second devices, comprising steps of: (a 1 ) during finite time periods following transmission of respective first messages from the first device to the second device, using the first device to listen for second messages transmitted from the second device to the first device; (a 2 ) after each of the finite time periods following the transmission of the respective first messages from the first device to the second device, ceasing to use the first device to listen for second messages transmitted from the second device to the first device until after the first device transmits another first message to the second device; (a 3 ) ceasing to use the second device to listen for first messages received from the first device at least occasionally when the second device is operational; (b) with the first device, receiving a sensor input from an accelerometer supported by a person in locomotion on foot; and (c) in response to the sensor input, with the first device, generating processed data comprising at least one of at least one foot contact time, a distance traveled, a pace, and a speed of the person for inclusion in at least one of the first messages that are transmitted to the second device.