High speed embedded protocol for distributed control systems

A method of communication among two or more modules over a common control network, the method comprising:

• during transmission of a message packet over a control network according to a first protocol, sending from a first module over the control network a second message embedded within the message packet using a second protocol;
• wherein the first protocol is defined in part by:
• a receiving device checking at a sample point within a received first protocol bit to determine a value of the bit, and
• the receiving device adjusting a position of the sample point within the received first protocol bit in response to sensing a transition edge within a defined portion of the received first protocol bit;
• the method further comprising transmitting a series of bits according to the first protocol having the transition edge to effect movement of the sample point for a receiving communication device to provide additional room within a first protocol bit in which to embed the second message using the second protocol.

A communication device apparatus for communicating with other devices over a control network, the communication device apparatus comprising:

• a communication port configured to connect to a control network;
• a processing device operatively connected to the communication port to
• transmit a message packet over a control network according to a modified CAN-FD protocol, the message packet having a first portion having a first data rate and a second portion having a second data rate higher than the first data rate, and
• send a dominant bit following a recessive signal to define an edge at a beginning of the second portion of the message;
• wherein the modified CAN-FD protocol is defined in part by a receiving device adjusting a position of a sample point for second portion bits in response to sensing the edge.

An apparatus for use in communicating with other devices over a control network, the apparatus comprising:

• a processing device configured to operatively connect through a communication port to control receiving and sending communications over a control network;
• the processing device configured to communicate, during transmission of a message packet over the control network according to a first protocol, a second message embedded within the message packet using a second protocol;
• wherein the first protocol is defined in part by:
• a receiving device checking at a sample point within a received first protocol bit to determine a value of the bit, and
• the receiving device adjusting a position of the sample point within the received first protocol bit in response to sensing a transition edge within a defined portion of the received first protocol bit;
• wherein the processing device is further configured to transmit a series of bits according to the first protocol having the transition edge to effect movement of the sample point for a receiving communication device to provide additional room within a first protocol bit in which to embed the second message using the second protocol.