Information processing system in which information expressing a current time point is transmitted from one computer to another for use in calculating an amount of delay in transferring data between the computers

• US 20060206613A1
• Filed: 03/09/2006
• Published: 09/14/2006
• Est. Priority Date: 03/09/2005
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Narita, Nobuaki
• Granted Patent: US 7,949,120 B2
• Time in Patent Office: Days
• US Class Current: 709/227
• CPC Class Codes: B60W 2050/065 by reducing the computational load on the digital processor of the control computer
• CPC Class Codes: F16H 59/18 dependent on the position of the accelerator pedal
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols

Abstract

In a system in which a first computer transmits data to a second computer, the first computer transmits data conveying time information to the second computer, with the information expressing a first time point that occurs prior to commencement of the transmission and, following reception of the time information, the second computer compares the first time point information with a current time point, to thereby obtain a communication delay amount that includes a delay in transmitting data from the first to the second computer.

Claims

1. An information processing system comprising a first computer and second computer which mutually communicate via a data communication line, and time counter means for deriving time point information expressing successive current time point values and for providing said time point data to each of said first computer and second computer, with said first computer comprising first communication means for communicating with said second computer via said data communication line and said second computer comprising second communication means for communicating with said first computer via said data communication line,

wherein:

said first communication means periodically or at irregular intervals executes a transmission operation for transmitting time point information via said data communication line to said second communication means, said time point information expressing a first time point, that is derived by said time counter means prior to commencement of said transmission operation, and

said second computer comprises delay calculation means for receiving said time point information from said second communication means, and for calculating a communication delay amount based on said first time point value and on a second time point value that is measured by said time counter means subsequent to reception of said time point information, said communication delay amount thereby including a time interval that elapses in transmitting data from said first computer to said second computer via said data communication line.

2. An information processing system according to claim 1, wherein:

said first communication means of said first computer periodically or at irregular intervals transmits respective specific data sets to said second communication means of said second computer via said data communication line, said specific data sets conveying information other than time point information;

said second computer performs calculation processing based on each of said specific data sets; and

,

said second computer applies compensation to said calculation processing, based upon said delay amount.

3. An information processing system according to claim 2, wherein:

said first computer received input values that are produced by an input apparatus; and

,

said input values constitute said information conveyed in said specific data sets.

4. An information processing system according to claim 3, wherein successive ones of said input values are conveyed in respective ones of said specific data sets.

5. An information processing system according to claim 4, wherein:

said input apparatus comprises a first sensor, for deriving successive detected values of a first physical quantity, and said input values comprise said detected values of the first physical quantity;

said second computer receives successive detected values of a second physical quantity from a second sensor, said second physical quantity being different from said first physical quantity; and

,

said second computer repetitively performs a calculation based on a combination of a detected value of said second physical quantity, obtained at a current time point of said calculation, and a received detected value of said first physical quantity, and applies compensation to a result of said calculation based upon said delay amount, for eliminating an error in said result due to a deviation between a time point currently measured by said time counter means and a time point of deriving said detected value of said first physical quantity by said first sensor.

6. An information processing system according to claim 2, wherein:

said first communication means of said first computer transmits each said specific data set to said second communication means together with time point information corresponding to said information conveyed in said specific data set.

7. An information processing system according to claim 1, wherein:

said time counter means comprises a first time counter of said first computer and a second time counter of said second computer;

each of said first computer and said second computer is responsive to each of successive occurrences of a predetermined concurrent event for resetting the corresponding one of said first time counter and second time counter at a time point of said occurrence;

at each occasion when time point information is received from said first communication means of said first computer by said second communication means of said second computer, said delay calculation means of said second computer calculates said delay amount based upon a time point value that is currently measured by said second time counter and said time point value expressed by said received time point information.