Patent ID: 7548581

Claim:
An AT-command analyzing device, comprising: a controller which analyzes a rate of a received AT-command; a first counter which measures the span of the start bit of the first character of the AT-command based on instructions from the controller; a decoder which receives an output of the first counter and outputs, when the rate of the start bit is more than a preset value, a flag indicating that the rate of the start bit is more than the preset value, and outputs frequency-dividing data obtained based on the output of the first counter; a second counter which selects, in accordance with whether or not the flag has been set, the frequency-dividing data from either the decoder or the controller, and produces the sampling clock; and a shift-register which receives data subsequent to the start bit of the first character based on the sampling clock produced by the second counter, and holds the received data, which data is then read by the controller.