Data transfer system

A data transfer method for transferring digital data from a sender to a receiver comprising the steps of:

• converting numerical data to be transferred into a sequence of character codes representing a numeral thereof;
• affixing a start code to the beginning of said converted sequence of character codes;
• affixing error detection data following said converted sequence of character codes;
• affixing a predetermined transfer control code following said error detection data;
• forming a transfer frame by said individual codes;
• computing a parity code for a character code representing said numeral;
• dividing a plurality of parity bits constituting said computed parity code into a plurality of parity bit groups;
• affixing to each of the divided parity bit groups a predetermined code different from said predetermined transfer control code to form a plurality of modified parity bit groups corresponding to the parity bit groups;
• constituting said error detection data by said plural parity bit groups;
• and
• transferring said transfer frame to a controller on a receiver side from a controller on a sender side.