Data buffering device having simple data reading and/or storing function

Abstract

A data buffering device having a data buffer permitting data storage in a first storage area A while the area A is advanced over a predetermined number of storage areas of the buffer in a predetermined sequence and permitting data reading from a second storage area B while the area B is advanced in the same sequence; a first device judging whether or not it is permissible to carry out at least one of a simple data storage and a simple data reading; a second device executing, if the judgement of the first device is negative, a return judgement whether or not it is necessary to return a corresponding one, or each, of the areas A and B to a leading storage area of the buffer, and a possibility judgement whether or not the buffer has at least a predetermined number of storage area or areas permitting a corresponding one, or each, of a data storage and a data reading, if the possibility judgement is affirmative the second device placing the first device in a condition in which the first device provides an affirmative judgement, and carrying out the corresponding one or each of the data storage and reading; and a third device carrying out, if the judgement of the first device is affirmative, the at least one of the simple data storage and reading, without the return and possibility judgements of the second device.