Hewlett-packard Company

Hewlett-packard Development Company, L.P.

Mark J Jedrzejewski

Gregory A Standiford

Mark A Wahl

Makarand P Gore

Shane Ward

Mark E Nash

John W Slattery

Linden H McClure

Terry W Norton

Disclosed herein is a temperature monitoring system including a circuit board and a thermochromic coating covering at least a portion of the circuit board, wherein the thermochromic coating is capable of indicating a temperature gradient on the circuit board. The thermochromic coating may comprise a color forming leuco dye, an activator, and optionally a deprotecting agent.

Temperature monitoring system

Two interfaces or operating modes are designed into the hardware and firmware. Selection between these two interfaces, or operating modes, is indicated by the position of a jumper on an IDE/ATAPI-style jumper block. A pull-up resistor and interface type detection signal are connected to a pin on the IDE/ATAPI-style jumper block associated with a jumper that is not monitored by the IDE/ATAPI master/slave selection detect (or other configuration) hardware or used to pull-down or pull-up another jumpered pin on the jumper block. When a jumper is placed between this pin, and a pin used to pull-up or pull-down another jumpered pin the interface type detection signal will be read as being at the pulled-up or pulled-down logic level, respectively. Otherwise, the IDE/ATAPI master/slave selection (or other configuration) detect hardware will function normally.

Selection apparatus and method

A device for connection to a Universal Serial Bus (USB) signals connection and disconnection from the bus without physically removing or reinserting the USB cable. The devices system controller controls the signaling so that connection or disconnection may be signaled in a variety of situations to accomplish certain tasks. Connection signaling may be delayed until power-up reset procedures are complete to prevent the device from being polled by the host. A disconnect then a connect may be signaled to help recover from certain error conditions. The same data lines may also be used for interfaces other than the USB bus. A switched connection from a USB data line through a pull-up resistor to a positive supply voltage. The switched connection is controlled by a logic function so that it will not be connected when the power supply on the USB cable is not present. The switched connection is also controlled by a logic signal that may be supplied by the USB device's system controller.

Universal serial bus controlled connect and disconnect

Firmware updates for embedded systems are accomplished by using PROM in favor of conventional ROM, dividing the PROM into pages zero, one, two, etc., that can each contain an entire version of the embedded system. Pages of PROM are addressable by MSB address bits that originate from a circuit that selects page zero upon power-up, and that is responsive to a command in the firmware of the embedded system to increment the value of the MSB address bits. Upon initial fabrication, a product containing the embedded system has entirely unprogrammed PROM. An initial embedded system is zapped into page zero when the product is tested after being turned on for the first time. Replacement versions can be zapped into successive pages as the need arises. Each version includes an initialization routine and its own Get Next Page (GNP) bit. If a version is superseded by another, the old version indicates this by a GNP bit that gets programmed on the old page at the same time the replacement version is zapped into the new page. When that GNP bit is checked by its initialization routine the page selecting MSB address bits are incremented and the micro-processor executing the embedded system is reset; it now runs the initialization routine of the replacement version on the next page, which if not itself replaced, eventually branches out of the initialization routine to the main code of the replacement embedded system.

Method and apparatus for firmware upgrades in embedded systems

A configurable driver/termination circuit for use in a peripheral device connected to a computer input/output controller bus. The driver/termination circuit has the pull-up current source characteristics of a three-state driver and the pull-down current sink characteristics of a open collector driver. Logic circuit defines the operating mode. In a default mode, the driver/termination circuit can function in either open collector or three-state bus designs. The circuit mode is changed by command from a host computer to explicitly operate as an open collector driver/terminator, as a three-state driver, or as an inactive high impedance. Alternatively, peripheral devices automatically select the mode which minimizes data transmission errors.

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Thornton, CO, United States of America

Mark J Jedrzejewski