Method and device for increasing the data transmission capacity in a serial bus system
First Claim
1. A method for serial data transmission processing in a bus system that includes a bus and at least two subscribed data processing units that are configured to exchange messages via the bus, the method comprising:
- obtaining a message transmitted by one of the at least two subscribed data processing units and on the bus, wherein the message is structured according to a predefined logical structure that includes a start-of-frame bit, an arbitration field, a control field including a data length code, a data field, a CRC field, an acknowledge field, and an end-of-frame sequence;
interpreting according to a first interpretation implemented when a switchover condition is not satisfied, by a data processing device, the data length code to determine a length of the data field; and
when the switchover condition is satisfied, the data processing device;
(i) switching from the first interpretation to a second interpretation that is at least partially in deviation from the first interpretation, and (ii) interpreting according to the second interpretation the data length code to determine the length of the data field,wherein;
at least one of the first interpretation and the second interpretation is performed according to an algorithm that causes the processing device to interpret certain values of the data length code as indicating respective lengths of the data field that are more than eight bytes,the switchover condition is one of satisfied or not satisfied based on at least one switchover bit included in a portion of the message that does not include the data length code, andthe data length code is composed of four bits.
1 Assignment
0 Petitions
Accused Products
Abstract
In a bus system that includes at least two subscribed data processing units that exchange messages via a bus in a serial data transmission, the transmitted messages are of a logical structure that includes a start-of-frame bit, an arbitration field, a control field, a data field, a CRC field, an acknowledge field and an end-of-frame sequence, the control field including a data length code, which contains information regarding the length of the data field. The messages are constructed such that the data field of the messages can include more than eight bytes, and, in a method of such serial data transmission, the values of the data length code are interpreted at least partially in a manner that deviates from the CAN standard ISO 11898-1 for determining the size of the data field.
-
Citations
34 Claims
-
1. A method for serial data transmission processing in a bus system that includes a bus and at least two subscribed data processing units that are configured to exchange messages via the bus, the method comprising:
-
obtaining a message transmitted by one of the at least two subscribed data processing units and on the bus, wherein the message is structured according to a predefined logical structure that includes a start-of-frame bit, an arbitration field, a control field including a data length code, a data field, a CRC field, an acknowledge field, and an end-of-frame sequence; interpreting according to a first interpretation implemented when a switchover condition is not satisfied, by a data processing device, the data length code to determine a length of the data field; and when the switchover condition is satisfied, the data processing device;
(i) switching from the first interpretation to a second interpretation that is at least partially in deviation from the first interpretation, and (ii) interpreting according to the second interpretation the data length code to determine the length of the data field,wherein; at least one of the first interpretation and the second interpretation is performed according to an algorithm that causes the processing device to interpret certain values of the data length code as indicating respective lengths of the data field that are more than eight bytes, the switchover condition is one of satisfied or not satisfied based on at least one switchover bit included in a portion of the message that does not include the data length code, and the data length code is composed of four bits. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27)
-
-
28. A data processing device which is one of a plurality of data processing devices subscribed to a bus of a bus system for exchanging messages over the bus via serial data transmission, the data processing device comprising:
-
a processor configured to; obtain a message transmitted on the bus by another of the plurality of data processing devices, wherein the message is structured according to a predefined logical structure that includes a start-of-frame bit, an arbitration field, a control field including a data length code, a data field, a CRC field, an acknowledge field, and an end-of-frame sequence; interpret, according to a first interpretation implemented when a switchover condition is not satisfied, the data length code to determine a length of the data field; and when the switchover condition is satisfied;
(i) switching from the first interpretation to a second interpretation that is at least partially in deviation from the first interpretation, and (ii) interpreting according to the second interpretation the data length code to determine the length of the data field,wherein; the data length code comprises four bits that provide for a total of 16 possible bit value combinations, the total of 16 possible bit combinations represents the length of the message in the data field; at least one of the first interpretation and the second interpretation is performed according to an algorithm that causes the processor to interpret certain values of the data length code as indicating respective lengths of the data field that are more than eight bytes; and the switchover condition is one of satisfied or not satisfied based on at least one switchover bit included in a portion of the message that does not include the data length code. - View Dependent Claims (29, 30, 31)
-
-
32. A method for serial data transmission processing in a bus system that includes a bus and at least two subscribed data processing units that are configured to exchange messages via the bus, the method comprising:
-
encoding in at least one switchover bit of a message, by one of the at least two subscribed data processing units, a switchover condition that indicates whether the message is to be interpreted by an other one of the data processing units according to;
(i) a first interpretation when the switchover condition is not satisfied, or (ii) a second interpretation when the switchover condition is satisfied, wherein the second interpretation is at least partially in deviation from the first interpretation; andtransmitting the message by the one of the at least two subscribed data processing units and on the bus, wherein the message is structured according to a predefined logical structure that includes a start-of-frame bit, an arbitration field, a control field including a data length code, a data field, a CRC field, an acknowledge field, and an end-of frame sequence, wherein; the length of the data field is greater than eight bytes; the data length code comprises four bits that provide for a total of 16 possible bit value combinations; the total of 16 possible bit value combinations represents the length of the message in the data field; the at least one encoded bit is included in a portion of the message that does not include the data length code; and the first interpretation and the second interpretation interpret the four bits of the data length code. - View Dependent Claims (33, 34)
-
Specification