External interface detection circuit of keyboard plate

The invention provides an external interface detection circuit of a key board, which is used for detecting the working current of the key board so as to judge a power input interface. The interface detection circuit identifies an interrupt signal of the sensor so as to judge an interrupt signal interface; the interface detection circuit identifies an angular velocity sensor L3GD statement, an acceleration sensor MMA statement, a geomagnetic sensor ST480 statement and a key extender KEY statement so as to judge whether sensing data of the sensors are valid or not and whether a key value detected by the key extender is correct or not; the interface detection circuit can control the on and off of the LED lamp on the detected key board so as to judge whether the LED lamp control interface is normal or not; the interface detection circuit transmits a detection result to a detection terminal in a TTL serial port mode. 本发明提供了一种按键板的对外接口检测电路，所检测电路对按键板工作电流进行检测，以对电源输入接口进行判断；所述接口检测电路识别传感器的中断信号，以对中断信号接口进行判断；所述接口检测电路识别角速度传