Universal serial bus peripheral bridge simulates a device disconnect condition to a host when the device is in a not-ready condition to avoid wasting bus resources

A Universal Serial Bus to parallel bus bridge comprising:

• a D+ and a D− serial bus connection;
• a peripheral-device-ready signal parallel bus connection;
• and
• a serial bus disconnect circuit connected to said peripheral-device-ready signal parallel bus connection, said serial bus disconnect circuit responding to a floating condition or a not-ready signal appearing at said peripheral-device-ready signal parallel bus connection by providing for a single-ended zero state on said D+ and D− serial bus connections.

A Universal Serial Bus to IEEE-1284-1994 compliant parallel bus bridge comprising:

• a Universal Serial Bus port having a D+ connection, a D− connection, a Vbus connection, and a serial bus ground connection;
• an IEEE-1284-1994 compliant parallel port having a Peripheral Logic High signal connection;
• and
• a serial bus disconnect circuit tied to said Peripheral Logic High signal connection, said serial bus disconnect circuit responding to a floating condition or a deassert signal appearing at said Peripheral Logic High signal connection by providing for a single-ended zero state on said D+ and D− connections.