Device connected to a bus and method for operating the device

• US 20040003143A1
• Filed: 04/25/2003
• Published: 01/01/2004
• Est. Priority Date: 04/25/2002
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Herz, Karl, Vowe, Achim, Barrenscheen, Jens
• Granted Patent: US 7,340,539 B2
• Time in Patent Office: Days
• US Class Current: 710/1
• CPC Class Codes: H04L 12/40032 Details regarding a bus interface enhancer
• CPC Class Codes: H04L 12/40163 by assigning priority to messages according to a message field
• CPC Class Codes: H04L 12/4135 using bit-wise arbitration
• CPC Class Codes: H04L 2012/40215 Controller Area Network CAN
• CPC Class Codes: H04L 49/90 Buffering arrangements

Abstract

A device that is connected to a bus can transmit data to one or more other devices and/or can receive data from other devices, through the bus, includes storage (i.e., memories or memory areas) in which data to be transmitted or received is temporarily stored, and a control device that determines whether or not any data is to be transmitted and, if appropriate, in which storage the data that are to be transmitted next is stored and/or in which storage the received data is to be stored. Information not contained in the data transmitted through the bus is stored in each storage, and is used to allocate a priority level to the respective storage, and the control device takes this information into account to decide the storage in which the next data to be transmitted will be stored and/or the storage in which the received data is to be stored.

Claims

1. A bus-connected device at least one of transmitting data to at least one other device through a bus and receiving data from at least one other device through the bus, comprising:

storage devices in which data to be transmitted or received is temporarily stored, said storage devices being memories or memory areas and storing information not contained in the data transmitted through the bus;

a control device connected to said storage devices and programmed to at least one of;

determine if any data is to be transmitted and, if data is to be transmitted, to determine which of said storage devices is storing the data to be transmitted next; and

determine in which of said storage devices the received data are to be stored; and

said control device being programmed to utilize the information to allocate a priority level to a respective one of said storage devices and to take the information into account when deciding at least one of;

which of said storage devices stores the data to be transmitted next; and

in which of said storage devices the received data are to be stored.

2. The device according to claim 1, wherein said control device is programmed to search all available ones of said storage devices when determining at least one of which of said storage devices stores the data to be transmitted next and in which of said storage devices the received data are to be stored.

3. The device according to claim 2, wherein, while searching through said available storage devices, said control device is programmed to simultaneously determine which of said storage devices stores the data to be transmitted next and in which of said storage devices the received data are to be stored.

4. The device according to claim 2, wherein said control device is programmed to search said storage devices in a predetermined sequence.

5. The device according to claim 4, wherein:

said control device contains a list; and

said list predetermines said sequence.

6. The device according to claim 4, wherein:

said storage devices store pointers predetermining said sequence; and

said pointers at least one of;

point to the storage device following the storage device containing the respective pointer in said sequence; and

point to the storage device preceding the storage device containing the respective pointer in said sequence.

7. The device according to claim 2, wherein said control device is programmed to take into account only said storages devices that, among the searched ones of said storage devices, contain priority information representing a highest priority level found when determining which of said storage devices stores the data to be transmitted next and in which of said storage devices the received data are to be stored.

8. The device according to claim 7, wherein said control device is programmed to choose from said storage devices to be taken into account, as said storage device to be determined, said storage device that was a first one of said storage devices to be taken into account that has been found when searching said available storage devices.

9. The device according to claim 7, wherein said control device is programmed to choose from said storage devices to be taken into account as a storage device to be determined, said storage device having contents with the best chance of winning an arbitration process carried out when at least two devices connected to the bus emit data to the bus at the same time.

10. The device according to claim 7, wherein said control device is programmed to choose from said storage devices to be taken into account as a storage device to be determined, said storage device stipulated which is according to stipulation in said control device to be used at the current time.

11. The device according to claim 7, wherein:

said control device is programmed to select said storage device to be determined based upon different criteria from said storage devices to be taken into account; and

the criterion on which said selection is based depends on said priority information of said storage device to be taken into account.

12. The device according to claim 1, wherein, when determining which of said storage devices stores the data to be transmitted next and in which of said storage devices the received data are to be stored, said control device being programmed to ignore ones of said storage devices containing specific priority information in given circumstances.

13. The device according to claim 1, wherein the device is a node in a controller area network.

14. A bus-connected node in a controller area network at least one of transmitting data to at least one other device through a bus and receiving data from at least one other device through the bus, comprising:

storage devices in which data to be transmitted or received is temporarily stored, said storage devices being memories or memory areas and storing information not contained in the data transmitted through the bus;

a control device connected to said storage devices and programmed to at least one of;

determine if any data is to be transmitted and, if data is to be transmitted, to determine which of said storage devices is storing the data to be transmitted next; and

determine in which of said storage devices the received data are to be stored; and

said control device being programmed to utilize the information to allocate a priority level to a respective one of said storage devices and to take the information into account when deciding at least one of;

which of said storage devices stores the data to be transmitted next; and

in which of said storage devices the received data are to be stored.

15. The device according to claim 14, wherein said control device is programmed to ignore ones of said storage devices containing specific priority information if the node is a node usable in a time-triggered controller area network but is being used as a node in a normal controller area network.

16. The device according to claim 14, wherein said control device is programmed to ignore ones of said storage devices containing specific priority information if the node is a node in a time-triggered controller area network and the time-triggered controller area network is currently in an arbitration window.

17. The device according to claim 15, wherein said control device is programmed to ignore ones of said storage devices containing specific priority information if the node is a node in a time-triggered controller area network and the time-triggered controller area network is currently in an arbitration window.

18. The device according to claim 16, wherein said ones of said storage devices ignored when the time-triggered controller area network is currently in an arbitration window, and said ones of said storage devices ignored when the time-triggered controller area network is currently in an exclusive window, are different ones of said storage devices.

19. The device according to claim 14, wherein said storage devices are message objects.

20. A method for operating a bus device connected to a bus, which bus is connected to other devices, which comprises:

at least one of transmitting data from the bus device to at least one other device through the bus and receiving data from at least one other device through the bus;

temporarily storing data to be transmitted or received data in storage devices of the bus device, the storage devices being memories or memory areas;

storing information not contained in the data transmitted through the bus in the storage devices;

determining with a control device;

if any data is to be transmitted and, if data is to be transmitted, determining with the control device which of the storage devices is storing the data to be transmitted next; and

determining in which of the storage devices the received data are to be stored; and

utilizing the information with the control device to allocate a priority level to a respective one of the storage devices and taking the information into account with the control device when deciding at least one of;

which of the storage devices stores the data to be transmitted next; and

in which of the storage devices the received data are to be stored.