Granted Patent B2

US 9,298,529 · App. 14/290,924 · Granted Mar 29, 2016

Abstract

Claims (24)

1. A method, comprising:

initiating, by a device coupled to a Controller Area Network (CAN), transmission of a message via the CAN;

detecting an error by the device during the transmission;

including an indication of the error in at least one cyclic redundancy check (CRC) field of the message by inverting at least a subset of bits in the CRC field; and

continuing, by the device after having detected the error, the transmission of the message without triggering a bus error condition.

2. The method of claim 1 , wherein detecting the error includes detecting a memory transfer error with respect to a memory within the device.

3. The method of claim 2 , wherein detecting the memory transfer error occurs after transmission of an identification field of the message over a CAN bus.

4. The method of claim 1 , further comprising finishing the transmission of the message without causing or indicating the bus error condition.

5. The method of claim 1 , further comprising inverting each bit in the CRC field.

6. The method of claim 1 , further comprising indicating a corresponding type of failure internal of the device in the subset of bits.

7. A Controller Area Network (CAN) node, comprising:

message processing circuitry configured to receive a frame from a transmitter, the frame comprising a cyclic redundancy check (CRC) field, the message processing circuitry further configured to identify an internal error of the transmitter based upon the CRC field by determining that at least a subset of bits in the CRC field is inverted.

8. The CAN node of claim 7 , wherein the message processing circuitry is configured to determine that each bit in the CRC field is inverted.

9. The CAN node of claim 7 , wherein the message processing circuitry is configured to report the internal error as distinct from a bus error.

10. The CAN node of claim 7 , wherein the message processing circuitry is configured to report the internal error as one of a plurality of different types of internal errors originated by the transmitter.

11. The CAN node of claim 7 , wherein a first portion of the inverted bits in the CRC field corresponds to a first type of internal error and wherein a second portion of the inverted bits in the CRC field corresponds to a second type of internal error.

12. A Controller Area Network (CAN), comprising:

a transmitter node configured to initiate transmission of a message, detect an error internal to the transmitter node during the transmission, modify a portion of the bits in a CRC field of the message in response to the detection, and continue the transmission of the message; and

a receiver node coupled to the transmitter node, the receiver node configured to receive the message and to identify the error internal to the transmitter node based on the modified portion of the bits in the CRC field.

13. The CAN of claim 12 , wherein the transmitter node is configured to continue the transmission of the message without indicating a bus error.

14. The CAN of claim 12 , wherein to modify the portion of the bits, the transmitter node is configured to invert all bits in the CRC field.

15. The CAN of claim 14 , wherein the receiver node is configured to determine that all bits in the CRC field are inverted.

16. The CAN of claim 12 , wherein to modify the portion of the bits, the transmitter node is configured to invert fewer than all bits in the CRC field.

17. The CAN of claim 16 , wherein the receiver node is configured to identify which bits in the CRC field are inverted and to report the error as corresponding to one of a plurality of possible errors internal to the transmitter node.

Assignments (16)