Abstract: In a computing system, various components/devices communicate with each other. For example, a microprocessor may communicate with memory or may communicate with another microprocessor over a link. Various factors such as the frequency and transmission speed of a signal can distort what is being communicated over a link. The problem becomes more pronounced as the transmission speed increases. To address this problem, devices on both ends of a link can cooperate to equalize the link. Equalization involves configuring the transmitting device to alter the signal being transmitted so that certain distortions introduced during transmission are negated by the time the signal arrives at the receiving device. Given that each link can have slightly different characteristics, appropriate equalization parameters need to be ascertained for each link. Introduced herein are improved techniques for performing equalization that are quick yet provide equalization parameters that are stable even in a noisy high-speed link.

Abstract: A transmitter for a high speed serial communications link, a serial communications link, and a receiver for a high speed serial communications link are disclosed herein. In one embodiment, the transmitter includes: (1) a communications interface connected to a transmission medium having multiple lanes, and (2) a safe mode circuit coupled to the communications interface and configured to send data over the transmission medium in a safe mode, wherein in the safe mode at least one of the lanes is dedicated to transmitting a link detect signal for link detection.

Abstract: A receiver, transmitter and method for early packet header verification are provided. In one embodiment, the method includes: (1) receiving a payload flit of a preceding packet and a header flit of a current packet; and (2) using a Cyclic Redundancy Check (CRC) in the header flit to verify the payload flit of the preceding packet and the header flit of the current packet.

Abstract: A CRC generator, a method for computing a CRC of a data packet, and an electronic system, such as a circuit board, are disclosed herein. In one embodiment the method is for computing the CRC of a data packet to be transmitted on a serial communications link having multiple lanes. In one embodiment, the CRC generator includes: (1) a CRC calculator configured to define a CRC calculation of a data packet in sequential order and perform parallelized computations, according to the sequential order and the multiple lanes, to generate sub-CRC values and (2) combination circuitry configured to combine the sub-CRC values to provide the CRC value for the packet.

Abstract: A transmitter for a high speed serial communications link, a serial communications link, and a receiver for a high speed serial communications link are disclosed herein. In one embodiment, the transmitter includes: (1) a communications interface connected to a transmission medium having multiple lanes, and (2) a safe mode circuit coupled to the communications interface and configured to send data over the transmission medium in a safe mode, wherein in the safe mode at least one of the lanes is dedicated to transmitting a link detect signal for link detection.

Abstract: A transmitter for a serial communications link, a serial communications link and an electronic system are disclosed herein. In one embodiment, the transmitter includes: (1) a communications interface connected to a transmission medium and (2) a safe mode circuit coupled to the communications interface and configured to send data over the transmission medium in a safe mode.

Abstract: A receiver, transmitter and method for enabling a replay using a packetized link protocol are provided. In one embodiment, the method includes: (1) transmitting a stream of packets including an untagged packet and (2) using synchronized counters to determine a sequence ID of the untagged packet, which is a corrupt/lost packet that needs to be retransmitted.

Abstract: A receiver, transmitter and method for early packet header verification are provided. In one embodiment, the method includes: (1) receiving a payload flit of a preceding packet and a header flit of a current packet; and (2) using a Cyclic Redundancy Check (CRC) in the header flit to verify the payload flit of the preceding packet and the header flit of the current packet.

Abstract: A receiver, transmitter and method for early packet header verification are provided. In one embodiment, the method includes: (1) receiving a payload flit of a preceding packet and a header flit of a current packet; and (2) using a Cyclic Redundancy Check (CRC) in the header flit to verify the payload flit of the preceding packet and the header flit of the current packet.

Abstract: A CRC generator, a method for computing a CRC of a data packet, and an electronic system, such as a circuit board, are disclosed herein. In one embodiment the method is for computing the CRC of a data packet to be transmitted on a serial communications link having multiple lanes. In one embodiment, the CRC generator includes: (1) a CRC calculator configured to define a CRC calculation of a data packet in sequential order and perform parallelized computations, according to the sequential order and the multiple lanes, to generate sub-CRC values and (2) combination circuitry configured to combine the sub-CRC values to provide the CRC value for the packet.

Abstract: A transmitter for a serial communications link, a serial communications link and an electronic system are disclosed herein. In one embodiment, the transmitter includes: (1) a communications interface connected to a transmission medium and (2) a safe mode circuit coupled to the communications interface and configured to send data over the transmission medium in a safe mode.

Abstract: A receiver, transmitter and method for enabling a replay using a packetized link protocol are provided. In one embodiment, the method includes: (1) transmitting a stream of packets including an untagged packet and (2) using synchronized counters to determine a sequence ID of the untagged packet, which is a corrupt/lost packet that needs to be retransmitted.

Abstract: A receiver, transmitter and method for early packet header verification are provided. In one embodiment, the method includes: (1) receiving a payload flit of a preceding packet and a header flit of a current packet; and (2) using a Cyclic Redundancy Check (CRC) in the header flit to verify the payload flit of the preceding packet and the header flit of the current packet.