5 results about "Port expander" patented technology

A port extender provides individual flow control for ports multiplexed from a network device. The port extender is configured to multiplex a network device port across the front panel ports on the port extender. The port extender also determines that an input buffer for the network device port is overloaded, and generates a Priority-based Flow Control (PFC) frame identifying that the network device port is congested. The port extender sends the PFC frame via the network device port to the network device. The PFC frame causes the network device coupled to the network device port to discontinue sending data for transmission from the plurality of ports on the port extender.

The present invention discloses a pan-tilt control device and method for matching the rotation speed and torque of a pan-tilt. The device includes a micro-control unit electrically connected to a pan-tilt controller, and is provided with a port expander for outputting pulse signals with different duty cycles at the port expander according to the motion trend of the pan-tilt; a filtering circuit electrically connected to the micro-control unit through the port expander for filtering the pulse signals to form different reference levels; a digital-to-analog converter electrically connected to the filtering circuit for converting the reference levels into digital level signals; a driving circuit electrically connected to a power supply and a driving motor for controlling the current of the driving motor; a pulse modulation circuit electrically connected to the digital-to-analog converter and the driving circuit for adjusting the current of the driving motor according to a target peak current; and a pan-tilt driving motor electrically connected to the driving circuit and the pulse modulation circuit for driving the pan-tilt. The present invention can avoid excessive power consumption when the pan-tilt is locked, and motor out-of-step caused by insufficient torque when the rotation speed is increased, etc.

A network device of a motor vehicle network structure is described, comprising an Ethernet switch and a defined total number of network devices to be connected via the Ethernet switch, wherein a port expander is connected to the Ethernet switch, the port expander having a number of device ports corresponding to the difference between the total number and the number of device ports provided for network devices on the Ethernet switch.