Transmission apparatus and transmission method

• US 20040158650A1
• Filed: 12/01/2003
• Published: 08/12/2004
• Est. Priority Date: 05/30/2001
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Adachi, Tatsuya, Kasahara, Tetsushi, Nakamura, Seiji, Iwata, Kazuya
• Granted Patent: US 7,421,527 B2
• Time in Patent Office: Days
• US Class Current: 710/1
• CPC Class Codes: G06F 13/12 using hardware independent of the central processor, e.g. channel or peripheral processor
• CPC Class Codes: G06F 13/24 using interrupt G06F13/32 takes precedence

Abstract

A small-sized and low-cost transmission apparatus and a transmission method (having a high responsivity) capable of transmitting an interrupt signal with a small number of input/output terminals (without a dedicated line for interrupt signals) are provided. A first transmission apparatus of the present invention comprises a central processing unit for carrying out an interrupt process in response to an interrupt signal; an input/output section having at least one data line for transmitting data signals between a second transmission apparatus and the first transmission apparatus and for transmitting an interrupt signal from the second transmission apparatus to the first transmission apparatus; and an interrupt signal detecting section for detecting an interrupt signal from among signals transmitted from the second transmission apparatus via the data line.

Claims

1. A first transmission apparatus comprising:

a central processing unit for carrying out an interrupt process in response to an interrupt signal;

an input/output section having at least one data line for transmitting data signals between a second transmission apparatus and the first transmission apparatus and for transmitting an interrupt signal from said second transmission apparatus to the first transmission apparatus; and

an interrupt signal detecting section for detecting an interrupt signal from among signals transmitted from said second transmission apparatus via said data line.

2. A first transmission apparatus as claimed in claim 1, wherein said interrupt signal detecting section comprises a data signal quiescent period detecting section for detecting a data signal quiescent period during which said data signals are not transmitted on said data line, and detects a signal transmitted during said data signal quiescent period detected by said data signal quiescent period detecting section as an interrupt signal.

3. A first transmission apparatus as claimed in claim 2, wherein

said input/output section further comprises a command line for transmitting command signals at least from the first transmission apparatus to said second transmission apparatus, and transmits data signals between said second transmission apparatus and the first transmission apparatus via said data line in response to said command signals;

said data signal quiescent period detecting section detects any given period in a period from the end of a data signal transmitted in response to said command signal to the end of the next one of said command signal to transfer a data signal on a data line as said data signal quiescent period.

4. A first transmission apparatus as claimed in claim 2, wherein

said data signal quiescent period detecting section detects any given period in a first period T₁ (T₁ is any given period) starting from the end of said data signal as said data signal quiescent period.

5. A first transmission apparatus as claimed in claim 1, further comprising:

a data signal generating section for generating a data signal to be transmitted from the first transmission apparatus to said second transmission apparatus; and

a data signal dividing section for dividing said data signal to generate a plurality of divided data signals each having less than a certain amount of information, if said data signal has a certain amount of information or more;

wherein

said input/output section transmits a plurality of said divided data signals sequentially from the first transmission apparatus to said second transmission apparatus via said data line and has at least a certain transmission quiescent period after the completion of transmitting one of said divided data signals and before the start of transmitting the next one of said divided data signals.

6. A first transmission apparatus comprising:

a central processing unit for determining one transmission mode from among two or more transmission modes including a first transmission mode and a second transmission mode and for carrying out an interrupt process in response to an interrupt signal; and

an input/output section having a plurality of data lines;

wherein,

in said first transmission mode, said input/output section transmits data signals via all of said data lines;

in said second transmission mode, said input/output section transmits data signals via at least one of said data lines and receives an interrupt signal transmitted from said second transmission apparatus to said first transmission apparatus via at least another one of said data lines.

7. A first transmission apparatus as claimed in claim 6, further comprising an interrupt signal detecting section which has a data signal quiescent period detecting section and detects an interrupt signal from among signals transmitted from said second transmission apparatus via another one of said data lines;

wherein

said data signal quiescent period detecting section detects any given period in a period from the end of a data signal transmitted in response to a command signal transmitted from the first transmission apparatus to said second transmission apparatus to the end of the next one of said command signal to transfer a data signal on a data line as said data signal quiescent period;

in said first transmission mode, said interrupt signal detecting section detects a signal transmitted via another one of said data lines during said data signal quiescent period as an interrupt signal; and

in said second transmission mode, said interrupt signal detecting section detects a signal transmitted via another one of said data lines as an interrupt signal regardless of its transmission timing.

8. A second transmission apparatus comprising:

an input/output section having at least one data line for transmitting data signals between a first transmission apparatus and the second transmission apparatus and for transmitting an interrupt signal from the second transmission apparatus to said first transmission apparatus;

a data signal quiescent period detecting section for detecting a data signal quiescent period during which said data signals are not transmitted on said data line; and

an interrupt signal generating section for transmitting an interrupt signal to said input/output section during said data signal quiescent period.

9. A second transmission apparatus as claimed in claim 8, wherein

said input/output section further comprises at least a command line for transmitting command signals from said first transmission apparatus to the second transmission apparatus;

said data line transmits data signals between said first transmission apparatus and the second transmission apparatus in response to said command signals; and

said data signal quiescent period detecting section detects any given period in a period from the end of a data signal transmitted in response to said command signal to the end of the next one of said command signal to transfer a data signal on a data line as said data signal quiescent period.

10. A second transmission apparatus as claimed in claim 8, wherein

said data signal quiescent period detecting section detects any given period in a first period T₁ (T₁ is any given period) starting from the end of said data signal as said data signal quiescent period.

11. A second transmission apparatus as claimed in claim 10, wherein

said input/output section transmits said data signal, and transmits the next one of said data signal after expiring at least a second period T₂ starting from the end of said data signal;

said second period T₂ is a period which is at least one clock longer than said first period T₁.

12. A second transmission apparatus as claimed in claim 10, wherein

said data signal quiescent period detecting section detects a period starting at the point in time when a third period T₃ (T₃ is a period of one clock or more) has elapsed from the end of said data signal and ending at the point when a fourth period T₄ (T₄ is any given period) has,elapsed from said starting point as said data signal quiescent period.

13. A second transmission apparatus as claimed in claim 8, further comprising:

a data signal generating section for generating a data signal to be transmitted from the second transmission apparatus to said first transmission apparatus; and

a data signal dividing section for dividing said data signal to generate a plurality of divided data signals each having less than a certain amount of information, if said data signal has a certain amount of information or more;

wherein

said input/output section transmits a plurality of said divided data signals sequentially from the second transmission apparatus to said first transmission apparatus via said data line and has at least a certain transmission quiescent period after the completion of transmitting one of said divided data signals and before the start of transmitting the next one of said divided data signals.

14. A second transmission apparatus comprising:

a transmission mode determining section for determining one transmission mode from among two or more transmission modes including a first transmission mode and a second transmission mode on the basis of the information about a transmission mode transmitted from a first transmission apparatus to the second transmission apparatus or on the basis of a command signal transmitted from said first transmission apparatus to the second transmission apparatus;

an input/output section having a plurality of data lines; and

an interrupt signal generating section for generating an interrupt signal and transmitting it to said input/output section;

wherein

in said first transmission mode, said input/output section transmits data signals via all of said data lines;

in said second transmission mode, said input/output section transmits data signals via at least one of said data lines and transmits said interrupt signal from the second transmission apparatus to said first transmission apparatus via at least another one of said data lines.

15. A second transmission apparatus as claimed in claim 14, further comprising:

a data signal quiescent period detecting section for detecting any given period in a period from the end of a data signal transmitted in response to a command signal transmitted from said first transmission apparatus to the second transmission apparatus to the end of the next one of said command signal to transfer a data signal on a data line as said data signal quiescent period;

wherein

in said first transmission mode, said input/output section transmits said interrupt signal via another one of said data lines only during said data signal quiescent period;

in said second transmission mode, said input/output section transmits said interrupt signal via another one of said data lines regardless of whether it is during said data signal quiescent period or not.

16. A transmission method between a first transmission apparatus and a second transmission apparatus, comprising:

a data signal transmitting step of transmitting a data signal via a data line;

a data signal quiescent period detecting step of detecting a data signal quiescent period during which no data signal is transmitted on said data line in said second transmission apparatus;

an interrupt signal transmitting step of transmitting an interrupt signal from said second transmission apparatus to said first transmission apparatus during said data signal quiescent period; and

an interrupt processing step of carrying out an interrupt process in said first transmission apparatus based on said interrupt signal.

17. A transmission method as claimed in claim 16, further comprising:

a data signal generating step of generating a data signal to be transmitted in said first transmission apparatus or in said second transmission apparatus;

a data signal dividing step of dividing said data signal generated at said data signal generating step to generate a plurality of divided data signals each having less than a certain amount of information, if said generated data signal has a certain amount of information or more; and

a data signal transmitting step of transmitting a plurality of said divided data signals sequentially via said data line and providing at least a certain transmission quiescent period after the completion of transmitting one of said divided data signals and before the start of transmitting the next one of said divided data signals.

18. A transmission method between a first transmission apparatus and a second transmission apparatus each having a plurality of data lines, comprising:

a transmission mode determining step of determining one transmission mode from among two or more transmission modes including a first transmission mode and a second transmission mode;

a data signal transmitting step of transmitting data signals via all of said data lines in said first transmission mode;

an interrupt signal transmitting step of transmitting data signals via at least one of said data lines and transmitting an interrupt signal from said second transmission apparatus to said first transmission apparatus via at least another one of said data lines in said second transmission mode; and

an interrupt processing step of carrying out an interrupt process in response to said received interrupt signal in said first transmission apparatus.