Dell USA L P

Dell Products Inc.

Erik A Schuchmann

Stuart William Hayes

Joseph A Vivio

Farzad Khosrowpour

An adaptive card-sensitive bus slot system and method. The method and system include a substantially universal bus slot structure. In one embodiment, the substantially universal bus slot structure includes at least one Peripheral Component Interconnect adaptive key. In another embodiment, the substantially universal bus slot structure includes at least one Peripheral Component Interconnect adaptive key piston. In another embodiment, a data processing system includes the adaptive card-sensitive bus slot system.

Adaptive card-sensitive bus slot method and system

A filter circuit for filtering bus accesses from a computer bus (such as e.g. a bus conforming to the PCI standard) to a group of devices operably coupled to the computer bus in a computer system. The filter circuit operates in a filter mode and a non filter mode. In the non filter mode, the filter circuit allows bus accesses to pass from the computer bus to the group. In the filter mode, the filter circuit blocks bus accesses from passing to the group. Upon determining that a bus access is an allowable bus access, the filter circuit initiates a retry request to signal the bus master that initiated the allowable bus access to reinitiate the bus access, wherein the filter circuit allows the allowable bus access to pass to the group. The filter circuit includes a switch circuit and a control circuit that places the switch circuit in the conductive and non conductive switch states to allow bus accesses to pass and to be blocked from passing to the group, respectively. In the filter mode, the filter circuit allows bus accesses to pass from a device of the group to the computer bus. The filter circuit includes a second switch circuit for controlling the bus accesses by the device of the group. The control circuit includes a programmable logic device. The filter circuit can be used in debugging a computer system which has a malfunctioning flash ROM. A second flash ROM can be inserted into a PCI slot and the filter circuit activated to filter accesses directed towards the malfunctioning flash ROM during the boot-up of the computer system.

Filter-circuit for computer system bus

It has been discovered that providing a computer system with a hot pluggable power supply as well as a disconnectable resistive load allows a second power supply to be brought on-line while operating within the proper voltage range and then disconnecting the resistive load from the power supply so as to conserve energy and lower the operating temperature of the computer system. Such a system also conserves energy by reducing the size of the fan that the computer system requires. Such a system also allows for a the use of larger test resistor thus providing a more accurate load test. Such a system also allows for saving space as one test circuit can be used for both power supplies. Such a system also allows for a reduced capacity power supply as the power supply does not have to continuously supply power to the resistive test load.

Method for making redundant power supplies hot-pluggable

A power supply line of a communications interface provides communication between two devices when one device is unable to utilize the communications interface in a standard manner. The power supply line is specified to operate within a first voltage range and normally operates at a first voltage within a second voltage range, the second voltage range being within the first voltage range. A voltage circuit changes the power supply line to a second voltage outside of the second voltage range but within the first voltage range. A voltage detecting circuit coupled to the power supply line asserts a signal indicating when the second voltage is present on the power supply line, thereby providing communication between the first device and the other device.

Sideband communication on the standard parallel SCSI bus

The present application describes a tuned guard circuit device and method for controlling impedance levels of transmission lines on a printed circuit board having at least one ground plane and at least two circuit components coupled by a conductive transmission line. The guard circuit device of the present invention includes two etched conducting guard bands on the printed circuit board disposed on opposite sides of a selected transmission line and affixed in a spaced parallel relation to the transmission line. The guard bands are of substantially constant width and substantially constant distance from the ground plane and have substantially the same length as the transmission line, and each guard band has a first and a second terminal end. Also included is a capacitor connected to the ground plane and connected at each of the first and second terminal ends of each guard band wherein the guard bands are connected to ground through the capacitors. The guard circuit device controls the impedance level of the transmission line by varying the capacitance values of the capacitors to optimize the impedance level of the transmission line. The capacitance values of all the capacitors are, preferably, equal.

Growing community of inventors

Austin, TX, United States of America

Erik A Schuchmann