A machine for imprinting patterns onto uncured concrete in an elongated bed includes a frame for positioning the finishing machine over the bed. This \u201cwatcher\u201d security device may be integrated within the computer system or may be separate from it. If the uplink period indicated by the PSMP frame is insufficient to transmit the queued data, the STA transmits a data unit including a part of the queued data and a resource request message for the remaining queued data in the uplink period.