Abstract: A bit error measuring device for modem device, comprises; a bit error measuring unit for measuring a bit error in an input signal from the modem device, a clock controlling unit for controlling an output of a clock signal on the basis of a control signal outputted from the modem device, and a test pattern transmitting unit for transmitting a test pattern signal by synchronizing with the clock signal when clock pulses of the clock signal are outputted from the clock controlling unit, and for stopping a transmission of the test pattern signal when the clock pulses of the clock signal are not outputted from the clock controlling unit.

Abstract: A bit error measuring device for modem device, comprises; a control code detecting unit for detecting a flow control code set in an input signal from the modem device, and for masking the flow control code, a bit error measuring unit for measuring bit errors in the input signal of which the flow control code is masked, a clock controlling unit for controlling an output of a clock signal by the flow control code, and a test pattern transmitting unit for transmitting a test pattern signal by synchronizing with the clock signal when clock pulses of the clock signal are outputted from the clock signal controlling unit, and for stopping a transmission of the test pattern signal when the clock pulses of the clock signal are not outputted from the clock signal controlling unit.