Abstract: Approaches for communicating data from a source device to a target device. In one approach, a communicated data value is segmented into a plurality of data chunks at the source device. A sequence of interrupt transactions is transmitted from the source device to a system bus. The transmitting of each interrupt transaction in the sequence includes transmitting a target identifier on an address bus of the system bus, and the target identifier of each interrupt transaction in the sequence includes a respective one of the data chunks. The sequence of interrupt transactions from the system bus is received at the target device. The communicated data value is reassembled at the target device from the data chunks in the target identifier of the interrupt transactions in the sequence.

Abstract: Within a system comprising a programmable integrated circuit (IC), a method can include storing a first configuration within the system in a read-only memory that is independent of the programmable IC. The programmable IC, being loaded with the first configuration, comprises a circuit that accesses a data source external to the system over a communication link. A second configuration can be downloaded by the programmable IC from the data source. The second configuration can be stored within a random access memory within the system that is independent of the programmable IC. Responsive to a reconfiguration event, the programmable IC can be loaded with the second configuration from the random access memory.

Abstract: In one embodiment, an output driver is disclosed. The output driver has a first driving device (Q1) that has a first terminal coupled to a bus line terminal, and a second driving device (Q2) that has a first terminal coupled to the bus line terminal. The first driving device (Q1) is configured to couple the bus line terminal to a reference voltage when activated by a first control signal, and the second driving device (Q2) is configured to couple the bus line terminal to a first supply voltage (Vcc) when the second driving device (Q2) is activated by a second control signal. The output driver also has a controller configured to activate the second control signal after the first control signal is deactivated. The second control signal remains active for a first fixed period of time.

Abstract: Circuits and methods for a differential signal interface for coupling differential signals at a first frequency on a pair of opposite polarity signals to a multiple gigabit transceiver with generic buffers for receiving, transmitting or transceiving out of band signals at a second frequency lower than the first frequency are disclosed. Termination networks are provided coupling generic input buffers to respective ones of the pair of opposite polarity signals for receiving out of band signals where the opposite polarity signals are placed at voltages so that the differential voltage between them is below a threshold voltage. Methods for providing generic buffers with multiple gigabit transceivers for receiving and transmitting out of band signals on a differential signal interface are provided. Out of band signals are received when the out of band signaling protocol is not known.

Abstract: Circuits and methods for a differential signal interface for coupling differential signals at a first frequency on a pair of opposite polarity signals to a multiple gigabit transceiver with generic buffers for receiving, transmitting or transceiving out of band signals at a second frequency lower than the first frequency are disclosed. Termination networks are provided coupling generic input buffers to respective ones of the pair of opposite polarity signals for receiving out of band signals where the opposite polarity signals are placed at voltages so that the differential voltage between them is below a threshold voltage. Methods for providing generic buffers with multiple gigabit transceivers for receiving and transmitting out of band signals on a differential signal interface are provided. Out of band signals are received when the out of band signaling protocol is not known.

Abstract: A circuit for optimizing the transmission of data on a communication channel is disclosed. According to one embodiment of the invention, a circuit comprises a transmitter circuit having a programmable output characteristic and being coupled to a transmission media. The transmission media receives serial data from the transmitter circuit and couples the data to a receiver circuit by way of the transmission media. A signal quality monitor associated with the receiver circuit generates received signal quality data. Finally, a feedback path couples the received signal quality data to the transmitter circuit.

Abstract: Individual IP vendors can directly license their IP modules to PLD users. Each PLD has a unique device identifier (UDI). If a user obtains a license to use an IP module on a particular PLD, then the IP vendor issues the user an authorization code (AC). The user supplies the AC to a license manager. The license manager decrypts the AC and checks that the UDI of the supplied AC matches the UDI of the PLD. If the two match, then the license manager encrypts a key, and sends the encrypted key to the PLD. The PLD uses a private key to decrypt the key. When the configuration bitstream for the design is later sent to the PLD, the license manager encrypts the IP module portion of the bitstream with the key. The PLD receives the bitstream and uses the decrypted key to decrypt the IP module portion.