Event signaling between peripheral modules and a processing unit

• US 8,060,672 B2
• Filed: 06/12/2007
• Issued: 11/15/2011
• Est. Priority Date: 06/12/2006
• Status: Expired due to Fees

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Zenger, Hermann, Maul, Jürgen, Ziemann, Wolfgang, Tretter, Albert
• Primary Examiner(s): Hafiz; Tariq
• Assistant Examiner(s): YU, HENRY W
• Application Number:
  US11/811,941
• Publication Number:
  US 20080005428A1
• Time in Patent Office: 1,617 Days
• Field of Search: None
• US Class Current: 710/65
• CPC Class Codes: G06F 13/426 using an embedded synchronisation, e.g. Firewire bus, Fibre Channel bus, SSA bus

Abstract

There is described a method, a bus protocol, a peripheral module, a processing unit, a hub and also to a system consisting of said components, for event signaling between at least one peripheral module and a processing unit by means of a system bus. In this case the data to be transmitted data is encoded into a larger symbol space, from which a standard idle symbol is used in telegram pauses for synchronizing a connection between transmitter and receiver. A message present at the peripheral modules is enabled to be signaled to the processing unit independently of the telegram traffic initiated by the processing unit. This is achieved by a peripheral module wishing to signal an event to the processing unit sending to the processing unit in a telegram pause, instead of the standard idle character, a signaling sequence consisting of an alarm idle symbol and an alarm identifier which contain information about the relevant event as well as the module address of the peripheral module at which the event is present, with the information about the event also being transcoded into the larger symbol space.

Claims

1. A method for event signaling between at least one peripheral module and a processing unit connected to one another as part of an automation system configured to control an automated process via a system bus, comprising:

establishing a connection with the automation system by way of said at least one peripheral module;

operating the system bus based upon a system bus master, wherein the system bus master reads data from said at least one peripheral module or sends data to said at least one peripheral module;

using individual symbols for the data in a symbol space;

transcoding the data into a larger symbol space by an encoder, wherein the data are transmitted in a bit transmission layer via a transmitter;

using a telegram method for the transmission based upon a request/response paradigm, wherein specific symbols from the larger symbol space are used to identify a start and an end of a telegram, and wherein a standard idle symbol is used in telegram pauses to synchronize a connection between the transmitter and a receiver;

converting back the data via a decoder at the receiver;

sending a signaling sequence by said at least one peripheral module to the processing unit in a telegram pause instead of a standard idle symbol, to signal essentially in real time occurrence of a pending alarm and/or diagnostic event related to the process controlled by the automation system to the processing unit, wherein the signaling sequence has an alarm idle symbol and an alarm identifier, wherein the alarm identifier contains information about the pending alarm and/or diagnostic event related to the process controlled by the automation system and a module address of said at least one peripheral module with the event, and wherein the information about the pending alarm and/or diagnostic event is transcoded into the larger symbol space;

specifying a reaction time for the signaling sequence, the reaction time comprising a time of duration for transmitting the signaling sequence from said at least one peripheral module to the processing unit, and further comprising a delay time when a maximum-length telegram is transmitted before the signaling sequence;

displaying, within said reaction time, the alarm identifier containing the information about the pending alarm and/or diagnostic event and the module address of the peripheral module;

storing in a hold stage of said at least one peripheral module respective signaling sequences of further peripheral modules;

allocating in a priority stage of said at least one peripheral module a respective priority level to the signaling sequence of said at least one peripheral module and to the respective signaling sequences of said further peripheral modules, wherein the priority level of the signaling sequence is dynamically selected based on the importance of the pending alarm and/or diagnostic event related to the process being controlled by the automation system; and

forwarding from the priority stage a signaling sequence with a highest priority level, wherein the alarm identifier of each signaling sequence has a field containing the respective priority level.

2. The method as claimed in claim 1, wherein the signaling sequence is interrupted at any given point in a symbol string of the signaling sequence, if a request or a response telegram is sent.

3. The method as claimed in claim 1, wherein the processing unit is used as the system bus master.

4. The method as claimed in claim 1, wherein an interface module is used as the system bus master, wherein the interface module establishes a link between said at least one peripheral module and the processing unit via a field bus.

5. The method as claimed in claim 1, wherein the signaling sequence is sent by said at least one peripheral module until the processing unit signals by a corresponding telegram to the peripheral module that the signaling sequence has arrived at the processing unit.

6. The method as claimed in claim 1, wherein the processing unit and said at least one peripheral module are connected based upon a daisy-chain structure.

7. The method as claimed in claim 1, wherein the processing unit and said at least one peripheral module are connected based upon a backplane structure.

8. The method as claimed in claim 1, wherein the processing unit is a Programmable Logic Controller.

9. A peripheral module for communication with a processing unit connected to one another as part of an automation system configured to control an automated process via a system bus, comprising:

a transmitter for transmitting data to a system bus master, wherein the data are transcoded for transmission in a bit transmission layer at the transmitter by an encoder into a larger symbol space;

a receiver to receive data from the system bus master, wherein the data are converted in a smaller symbol space at the receiver by a decoder;

a telegram method based on a request/response paradigm used for data transmission, wherein specific symbols from the larger symbol space are used to identify a start and an end of a telegram, and wherein a standard idle symbol is used in telegram pauses for synchronizing a connection between the transmitter and the receiver; and

a signaling sequence for signaling essentially in real time occurrence of a pending alarm and/or diagnostic event related to the process controlled by the automation system to be sent by the peripheral module to the processing unit instead of a standard idle symbol, wherein the signaling sequence has an alarm idle symbol and an alarm identifier, wherein the alarm identifier contains information about the pending alarm and/or diagnostic event as well as the module address of the peripheral module, wherein a reaction time is specified for the signaling sequence, the reaction time comprising a time of duration for transmitting the signaling sequence from the peripheral module to the processing unit and further comprising a delay time when a maximum-length telegram is transmitted before the signaling sequence, and further wherein the alarm identifier containing the information about the pending alarm and/or diagnostic event and the module address of the peripheral module are displayed within the specified reaction time;

a hold stage configured to store respective signaling sequences of further peripheral modules; and

a priority stage configured to allocate a respective priority level to the signaling sequence of the peripheral module and to the respective signaling sequences of said further peripheral modules, the priority stage configured to forward a signaling sequence allocated with a highest level of priority, wherein the priority level of the signaling sequence is dynamically selected based on the importance of the pending alarm and/or diagnostic event related to the process being controlled by the automation system, wherein the alarm identifier of each signaling sequence has a field containing the respective level of priority.

10. The peripheral module as claimed in claim 9, wherein the information about the event is transcoded into the larger symbol space.

11. The peripheral module as claimed in claim 9, wherein the peripheral module has a sample stage to store a signaling sequence to be sent.

12. The peripheral module as claimed in claim 9, wherein the peripheral module has at least one further transmitter and at least one further receiver for connecting at least one further peripheral module.

13. The peripheral module as claimed in claim 12, wherein the peripheral module has a hold stage to store signaling sequences from said at least one further peripheral module.

14. The peripheral module as claimed in claim 13, wherein the peripheral module has a priority stage to evaluate the own signaling sequence and to evaluate the signaling sequence of further peripheral modules.

15. The peripheral module as claimed in claim 14, wherein a forwarding of the signaling sequence with a highest priority is based upon the priority stage.

16. The peripheral module as claimed in claim 14, wherein signaling sequences with the same priority are forwarded based upon a priority scheme applicable on the system bus.

17. A processing unit for communication with at least one peripheral module connected to one another as part of an automation system configured to control an automated process via a system bus, comprising:

a transmitter for transmitting data to said at least one peripheral module, wherein the data are transcoded for transmission in a bit transmission layer at the transmitter by an encoder into a larger symbol space;

a receiver to receive data from said at least one peripheral module, wherein the data are converted in a smaller symbol space at the receiver by a decoder;

a telegram method based on a request/response paradigm used for data transmission, wherein specific symbols from the larger symbol space are used to identify a start and an end of a telegram, and wherein a standard idle symbol is used in telegram pauses for synchronizing a connection between the transmitter and the receiver; and

a signaling sequence for signaling occurrence of a pending alarm and/or diagnostic event related to the process controlled by the automation system to be sent by the processing unit to the peripheral module instead of a standard idle symbol, wherein the signaling sequence has an alarm idle symbol and an alarm identifier, wherein the alarm identifier contains information about the pending alarm and/or diagnostic event as well as the module address of the peripheral module, wherein a reaction time is specified for the signaling sequence, the reaction time comprising a time of duration for transmitting the signaling sequence to the peripheral module and further comprising a delay time when a maximum-length telegram is transmitted before the signaling sequence, and further wherein the alarm identifier containing the information about the pending alarm and/or diagnostic event and the module address of the peripheral module are displayed within the specified reaction time, wherein the processing unit has a hold stage for storing signaling sequences of said at least one peripheral module and further peripheral modules, and wherein the processing unit has a priority stage for evaluating a priority level of the stored signaling sequences and processing a signaling sequence with a highest priority level, wherein the priority level of the signaling sequence is dynamically selected based on the importance of the pending alarm and/or diagnostic event related to the process being controlled by the automation system.

18. The processing unit as claimed in claim 17, wherein the processing unit is a system bus master.

19. The processing unit as claimed in claim 17, wherein the processing unit has at least one further transmitter and at least one further receiver for connecting at least one further peripheral module.