Data transmission apparatus and electronic control unit

• US 20030200366A1
• Filed: 02/25/2003
• Published: 10/23/2003
• Est. Priority Date: 04/19/2002
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kondo, Haruhiko, Komori, Hirokazu
• Granted Patent: US 7,299,308 B2
• Time in Patent Office: Days
• US Class Current: 710/52
• CPC Class Codes: F02D 41/2496 the memory being part of a closed loop
• CPC Class Codes: F02D 41/266 the computer being backed-up or assisted by another circuit, e.g. analogue
• CPC Class Codes: F02D 41/28 Interface circuits
• CPC Class Codes: G06F 5/06 for changing the speed of data flow, i.e. speed regularising or timing, e.g. delay lines, FIFO buffers; over- or underrun control therefor G06F7/78 takes precedence

Abstract

An electronic control unit has two microcomputers. Each microcomputer has a data buffer storing data to be transmitted in every 8 ms, a data buffer storing data to be transmitted in every 16 ms, and another data buffer storing data to be transmitted in every 16 ms and being different from the data buffer. The microcomputer transfers at the transmission timing of every 8 ms data in the data buffer to the transmitting buffer, while it transfers alternately the data in the data buffer and the data in the data buffer to the transmitting buffer. The microcomputer also transfers an ID that indicates content of the present transmitting data to the transmitting buffer.

Claims

1. A data transmission apparatus comprising:

a transmitting buffer for transmitting a plurality of data to other apparatuses;

a plurality of data buffers storing the plurality of data to be transmitted at specified transmission timings among a plurality of different transmission timings; and

a transmission process means identifying one of the plurality of data buffers storing data to be transmitted at the specified transmission timing from the plurality of data buffers, thereby to transfer the data in the identified data buffer to the transmitting buffer.

2. The transmission apparatus according to claim 1, further comprising:

a memory for storing a definition table that defines a relation between the plurality of data buffers storing the data to be transmitted and the plurality of the specified timings so that the transmission process means identifies the data buffer storing the data to be transmitted at the specified transmission timing based on the definition table.

3. The transmission apparatus according to claim 2,

wherein the transmission process means transfers to the transmitting buffer data of identification information indicating content of the data to be transmitted from the transmitting buffer.

4. An electronic control unit comprising:

a plurality of microcomputers for controlling control objects while performing data communications therebetween,

wherein the plurality of the microcomputers has a transmitting side microcomputer used for transmitting data and including a plurality of data buffers storing data to be transmitted at a plurality of specified transmission timings, and

the transmitting side microcomputer identifies one of the data buffers storing the data to be transmitted from the plurality of data buffers thereby to transfer the data in the identified data buffer to a receiving side microcomputer.

5. The electronic control unit according to claim 4,

wherein the transmitting side microcomputer has a memory storing a definition table defining a relation between the data buffers and the transmission timings, and

wherein the transmitting side microcomputer identifies the data buffer storing data to be transmitted at the specified transmission timing based on the relation defined in the definition table.

6. The electronic control unit according to claim 5,

wherein the transmitting side microcomputer transmits the data in the data buffer identified based on the definition table and identification information indicating content of data to be transmitted to the receiving side microcomputer.