Independent communication control apparatus and independent communication control method

• US 20010047458A1
• Filed: 04/20/2001
• Published: 11/29/2001
• Est. Priority Date: 05/23/2000
• Status: Abandoned Application

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Iizuka, Tsuyoshi
• Application Number:
  US09/838,324
• Publication Number:
  US 20010047458A1
• Time in Patent Office: Days
• US Class Current: 711/154
• CPC Class Codes: G06F 13/385 for adaptation of a particular data processing system to different peripheral devices

Abstract

The present invention aims to eliminate reading operation of control information from a memory by a communication control apparatus, to reduce the time required for sending process and to improve the system performance. The communication control apparatus connected to a processor executing an operating system (OS) and applications, for sending data to an outside device, has a communication control information table for specifying send control information received from the OS. On receiving a send activation instruction from the processor, the communication control apparatus specifies an address of the memory based on the instruction and contents of the send control information table, reads the data from the memory, and starts to send the data to a receiver.

Claims

1. An independent communication control apparatus, connected to a processor executing an operating system (OS) and an application and connected to a memory, for sending data to an outside device via a channel, comprising:

a communication control information table for specifying send control information received from the processor, and

wherein the independent communication control apparatus starts to send data to a receiver specified in the send control information on receiving a send activation instruction from the processor, and reads data from the memory based on the send activation instruction from the processor and contents of the communication control information table.

2. The independent communication control apparatus of

claim 1

, wherein the independent communication control apparatus sends the data to the channel in parallel with reading the data from the memory based on address information specified in the send activation instruction.

3. The independent communication control apparatus of

claim 1

, wherein the processor specifies a send data length in the send activation instruction, and the independent communication control apparatus sends the data at a time as a set of series having the send data length specified in the send activation instruction.

4. The independent communication control apparatus of

claim 1

,

wherein a send control domain to activate a sending process consists of plural send control areas, a size of which is one or multiple of space management unit of the OS, and each send control area is correspondent to an entry of the communication control table.

5. The independent communication control apparatus of

claim 4

, wherein the memory has plural send data buffer areas and send status buffer areas corresponding to each task for storing send data and send status.

6. The independent communication control apparatus of

claim 4

, wherein the processor activates the independent communication control apparatus directly from a task.

7. The independent communication control apparatus of

claim 6

, wherein only the task assigned to the send control area is allowed to activate the communication control apparatus through the send control area.

8. The independent communication control apparatus of

claim 1

, wherein an address of send data and an address of send data status are obtained by operating a predetermined addition/subtraction on the address of the memory specified in the communication control information table and address information specified in the send activation instruction.

9. The independent communication control apparatus of

claim 1

further comprising a queue buffer for storing the send activation instruction received from the processor, and

wherein the independent communication control apparatus starts to send the data to a receiver based on the send activation instruction stored in the queue buffer.

10. The independent communication control apparatus of

claim 9

,

wherein the processor sequentially transfers the send activation instruction to the queue buffer of the independent communication control apparatus;

and

wherein the independent communication control apparatus executes sending operation according to the send activation instruction stored in the queue buffer, and after finishing the sending operation of one set of data, and performs another sending operation according to a subsequent send activation instruction stored in the queue buffer.

11. The independent communication control apparatus of

claim 1

, wherein the communication control information table specifies a range of an address of the memory for storing the send data and informs of an error when the sending operation exceeds the range of the address of the memory.

12. A method for independent communication control having a communication controller connected to a processor executing an operating system (OS) and connected to a memory, for sending data to an outside device via a channel, and wherein the communication controller comprises a communication control information table for specifying send control information from the processor,

the method comprises:

specifying an address of the memory based on a send activation instruction from the processor and contents of the communication control information table; and

starting to send data to a receiver by reading the data from the memory.

13. The method for independent communication control of

claim 12

, the method further comprises:

reading the data from the memory by the communication controller based on address information specified in the send activation instruction; and

sending the data to the receiver in parallel with the reading.

14. The method for independent communication control of

claim 12

,

wherein the communication controller further comprises a queue buffer for storing the send activation instruction received from the processor, and

wherein starting to send data to the receiver by the communication controller is done based on the send activation instruction stored in the queue buffer.

15. The method for independent communication control of

claim 12

,

wherein the processor specifies a send data length in the send activation instruction, and

the method further comprises sending the data at a time as a set of series having the send data length specified in the send activation instruction.

16. The method for independent communication control of

claim 12

, the method further comprises setting the send activation instruction to a send control area by the processor directly from a task.