Usb connections

A system comprising:

• a host device having a plurality of ports connected to a host controller;
• a peripheral device having a plurality of ports connected to a peripheral controller;
• and
• a Universal Serial Bus (USB) cable between the host device and the peripheral device, the system providing a USB connection comprising a plurality of data channels, each data channel comprising a pair of signal links, each signal link comprising a port in the host device, a port at the peripheral device and a signal wire extending between corresponding ports, together with the host and peripheral controllers, each signal wire comprising one or more physical wires, wherein the USB connection is configured by:
• configuring both of the signal links of at least one of the data channels to be capable of transmitting data bidirectionally;
• initially determining a first direction for transmission of data for each of the bidirectionally configured signal links based on an initial required data transmission capacity in each direction between the first and second devices;
• transmitting data along each of the bidirectionally configured signal links in the determined first direction;
• selecting which of the bidirectionally configured signal links that are transmitting data in the first direction should change their direction of transmission to a second direction;
• sending a re-direction signal to each of the selected bidirectionally configured signal links to cause the selected bidirectionally configured signal links to change their direction of transmission of data to a second direction;
• and
• transmitting data along each of the selected bidirectionally configured signal links in the second direction.