Shift register unit and driving method thereof, gate drive circuit, display device

A shift register unit comprising an input subcircuit, an output subcircuit, a first reset subcircuit, a second reset subcircuit and a second node control subcircuit, wherein the input subcircuit is connected to a scan pulse input terminal and a first node, and is adapted to drive a voltage of the first node to be a first level when a scan pulse signal is of the first level,

• wherein the output subcircuit is connected to the first node, a first clock signal input terminal and an output terminal of the shift register unit, and is adapted to drive a voltage of the output terminal to be a level of a first clock signal inputted through the first clock signal input terminal when the voltage of the first node is of the first level, and to maintain the level of the first node when the first node is floating,
• wherein the second node control subcircuit is connected to the scan pulse input terminal, the output terminal of the shift register unit, a second clock signal input terminal, a second node, a first level DC voltage terminal and a second level DC voltage terminal, and is adapted to connect the second node with the second level DC voltage terminal when either of the scan pulse signal and an output signal of the output terminal is of the first level, and to connect the second node with the first level DC voltage terminal when each of the scan pulse signal and the output signal of the output terminal is of the second level and the second clock signal is of a predetermined level,
• wherein the first reset subcircuit is connected to the first node and the second node, and is adapted to drive the voltage of the first node to be the second level when the voltage of the second node is of the first level, and
• wherein the second reset subcircuit is connected to the second node and the output terminal, and is adapted to drive the output signal of the output terminal to be the second level when the voltage of the second node is of the first level.