Data communication system, encoder logic, decoder logic, and encoding and decoding method using the same

An encoder logic provided in a data communication system that drives a link unit consisting of four transmission lines with a PAM4 signal and utilizes twenty-four state symbols in which a sum of the PAM4 signals is zero and results of six comparators are non-overlapping based on graph coloring theory, the encoder logic configured to generate a signal for driving a PHY unit to encode and transmit a state symbol signal, the encoder logic comprising:

• a transmission initial position setting module configured to establish a specific position, set as an initial position in a state transition diagram having twenty-four state symbols where relative distances are defined by conversion symbols X, Y and Z, as a new position;
• a data input module configured to receive transmission data from a transmission data stream;
• and
• a transmission state determination module configured to verify whether the transmission data satisfies any one of a plurality of transmission conditions, determine a corresponding state, and establish a new position.

A decoder logic provided in a data communication system that drives a link unit consisting of four transmission lines with a PAM4 signal and uses 24 state symbols in which a sum of the PAM4 signals is zero and results of six comparators are non-overlapping based on graph coloring theory, the decoder logic configured to restore the 24 state symbols by receiving six PAM4 comparison signals output from a PHY unit of a communication unit, the decoder logic comprising:

• a reception initial position setting module configured to set a specific position, which is set as an initial position in a state transition diagram having 24 state symbols where relative distances between the state symbols are defined by conversion symbols X, Y and Z, as a new position, and set 0 as new data;
• a data analysis module configured to, upon receiving reception data from a reception data stream, set the new data as old data, set the reception data as the new data, calculate a data difference between the set old data and the set new data, and analyze the respective numbers of X, Y and Z;
• and
• a reception state determination module configured to check whether the reception data satisfies any one of a plurality of reception conditions based on the analyzed numbers of X, Y and Z and the reception data, and determine a corresponding state.

An encoding method comprising:

• (a) setting a specific position, which is set as an initial position in a state transition diagram having 24 state symbols where relative distances between the state symbols are defined by conversion symbols X, Y and Z, as a new position;
• (b) receiving transmission data from a transmission data stream;
• (c) when the transmission data satisfies a first transmission condition of 22, determining that the transmission data indicates an IDLE state, setting the new position as an old position, and setting a position converted by X from the old position as the new position;
• (d) transmitting a PAM4 value of data corresponding to the new position through a PHY to a transmission line, and then returning to step (b);
• (e) when the transmission data satisfies a second transmission condition of being greater than or equal to 0 and less than or equal to 10, determining that the transmission data indicates a ROTATE (R) state, setting the new position as an old position, setting a position obtained by adding Y(D+1) to the old position as the new position, and then returning to step (d);
• (f) when the transmission data satisfies a third transmission condition of being greater than or equal to 11 and less than or equal to 20, determining that the transmission data indicates a rotate-swap (RS) state, setting the new position as an old position, and after applying a rotate-swap (RS) to the old position, setting a position moved by Y(D-11) as the new position, and then returning to step (d);
• and
• (g) when the transmission data satisfies a fourth transmission condition of 21, determining that the transmission data indicates an END state, setting the new position as an old position, and after applying a rotate-swap (RS) to the old position, setting a position moved by Y(D-11) as the new position, and then returning to step (a).

A decoding method comprising:

• (a) in a state transition diagram having 24 state symbols where relative distances between the state symbols are defined by conversion symbols X, Y and Z, setting a specific position set as an initial position as a new position and setting 0 as new data;
• (b) upon receiving reception data from a reception data stream, setting the new data as old data, setting the reception data as the new data, calculating a data difference between the set old data and the set new data, and analyzing the respective numbers of X, Y and Z;
• (c) when a result of analyzing the reception data satisfies a first reception condition where a number of X is 1, a number of Y is 0 and a number of Z is 0, determining the reception data as an IDLE state, storing the reception data, and then returning to step (b);
• (d) when the result of analyzing the reception data satisfies a second reception condition where a number of X is 0, a number of Y is 1 to 11 and a number of Z is 0, determining the reception data as a position corresponding to Y-1, storing the reception data, and then returning to step (b);
• (e) when the result of analyzing the reception data satisfies a third reception condition where a number of X is 0, a number of Y is 0 to 9 and a number of Z is 1, determining the reception data as a position corresponding to 11+Y, storing the reception data, and then returning to step (b);
• and
• (f) when the result of analyzing the reception data satisfies a fourth reception condition where a number of X is 0, a number of Y is 10 and a number of Z is 1, determining the reception data as an END state, storing the reception data, and then returning to step (a).