Patent ID: 6339477
Filing Date: 2002-01-15
Classification: H04N

Abstract:
A data communication system capable of communicating data bi-directionally between a first information processing unit and a second information processing unit, comprising:a first information processing unit that provides a transmission request to determine whether there is data in the second information processing unit and that receives said data from said second information processing unit; and a second information processing unit that receives said transmission request provided by said first information processing unit and that sends said data to said first information processing unit in response to said transmission request when said second information processing unit contains said data, wherein said first information processing unit is further for repeatedly providing a subsequent transmission request to said second information processing unit at one of different first and second periodic time intervals depending on whether or not the first information processing unit receives said data, the first information processing unit repeatedly providing the subsequent transmission request to the second information processing unit at the first periodic time interval when said first information processing unit does not receive said data, the first information processing unit repeatedly providing said subsequent transmission request to said second information processing unit at the second periodic time interval, which is shorter than said first periodic time interval, when said first information processing unit receives said data.