Patent ID: 7092478

Claim:
A local timer, comprising: a first input circuit which has input thereto a first clock; a dividing counter which counts the first clock and outputs a reference counting signal, wherein a frequency of the reference counting signal is divided from the first clock; a timing synchronizing timer which counts a timing synchronizing timer value in synchronization with a reference timer in an access point, in response to the reference counting signal; a second input circuit which has input thereto a second clock, wherein a frequency of the second clock is less than a frequency of the first clock; a first buffer which stores a counted value of the dividing counter in synchronization with the second clock, when operation is in accordance with the first clock; a second buffer which stores the timing synchronizing timer value in synchronization with the second clock, when operation is in accordance with the first clock; a first adder which adds a first offset value or a second offset value to the counted value stored in the first buffer in synchronization with the second clock, when the first clock is suspended, wherein the first offset value and the second offset value are selected by a set ratio; and a second adder which adds a set value to the stored timing synchronizing timer value in response to a carry from the first adder, wherein the set value is set based on a ratio between the first clock and the second clock, wherein the first buffer sets therein the counted value to the output of the dividing counter in synchronization with the second clock, after the first clock is restarted, and wherein the second buffer sets therein the timing synchronizing timer value in synchronization with the second clock, after the first clock is restarted.