Freescale Semiconductor,inc.

Nxp Usa, Inc.

Amir Yosha

Hezi Rahamim

Graham Edmiston

Stefania Gandal

Yanina Zaslavsky

A master device has a slave port and a redundant slave port for communicating with slaves according to a network protocol, e.g. EtherCAT, via data packets including a circulating bit. The slaves are arranged in a sequence starting at the slave port, and are connected via a communication medium. A respective slave in the sequence detects whether the connection to its processing receiver is lost, and, if so, internally transfers any data packets from its forwarding arrangement to its processing arrangement, while setting the circulating bit. The master device has a switcher unit coupled to the redundant slave port and a last slave in the sequence. The switcher unit transfers data packets from the switcher receiver to the switcher transmitter, and detects whether a circulating bit is set. If so, the unit switches off said transferring and switches on a connection between the redundant slave port and the switcher for transferring replicated packets to the sequence. Advantageously, the system enables hot plug-in and also distributed clock synchronization, and reduces the processing requirements of the master device.

Redundant packet forwarding system

An EtherCAT packet forwarding system with distributed clocking is provided. The system comprises a master device and a plurality of slaves. The master comprises a processing port and a forward port for being respectively coupled to the at least two Ethernet ports of the master device in a redundant ring topology. The slaves comprise an internal clock indicating a current time, and a slave memory comprising a processing timestamp variable, a forwarding timestamp variable, a temporary timestamp variable and a copy-direct bit.

Ethercat packet forwarding with distributed clocking

An electronic device communicates according to a network protocol that defines data packets, for example EtherCAT. The device has a processor for performing input control on incoming data packets and performing output control on outgoing data packets, and a shared FIFO buffer comprising a multiuser memory. An input unit receives input data, detects the start of a respective data packet, subdivides the data packet into consecutive segments, one segment having a predetermined number of data bytes, and transfers the segment to the FIFO buffer before the next segment has been completely received. The processor accesses, in the input control, the multiuser memory for processing the segment, and, in the output control, initiates outputting the output packet before the corresponding input data packet has been completely received. An output unit transfers the segment from the FIFO buffer, and transmits the segment to the communication medium.

Method for cut through forwarding data packets between electronic communication devices

A device and a method for processing a frame, the method includes: receiving a frame; retrieving a lookup key parse command that includes an instruction field and an bitmap representative of selected frame fields to be searched in the frame; generating a lookup key by extracting at least one frame field if the type of the received frame matches an expected frame type; and looking up, using the lookup key, for additional frame processing instructions.

Growing community of inventors

Rishon Lezion, Israel

Amir Yosha