Method for data transmission

A method for transmitting data in a serial bus system, comprising:

• providing a network comprising a serial data bus, and further comprising a controller and a plurality of users connected to the bus, each user comprising a processor, a memory, a receive unit, and a transmit unit, and each user connected to an automation device for data input therefrom;
• transmitting a first telegram from the controller onto the bus, wherein the first telegram comprises a plurality of data fields, each said data field identified within the telegram for one of the users;
• each of the users sequentially becoming a receiving user of the first telegram via the bus, and each receiving user sequentially performing the steps of
• receiving the first telegram;
• forwarding the first telegram onto the bus toward a subsequent receiving user;
• determining if one of the data fields is identified in the first telegram for the receiving user, and, if so,
• reading said one of the data fields identified for the receiving user;
• preparing a receiving user response;
• and
• if the automation device attached to the receiving user provides input data needed for the receiving user response within a predetermined time limit, and if a response telegram of a subsequent receiving user is received by the receiving user within the predetermined time limit,
• then
• appending the receiving user response to the response telegram of the subsequent receiving user;
• and
• forwarding the response telegram of the subsequent receiving user toward the controller;
• else
• forwarding the response telegram received from the subsequent receiving user unchanged toward the controller;
• forming a new response telegram containing the receiving user response;
• and
• transmitting the new response telegram toward the controller;
• wherein a designated last one of the receiving users jumps from the preparing step to the forming step.