Apparatus And Method For Serial To Parallel In An I/O Circuit

A serial to parallel input/output circuit, comprising a plurality of selecting elements, each including:

• a first input terminal for receiving a first input signal;
• a second input terminal for receiving a second input signal;
• an enable control signal receiving terminal for receiving an enable control signal so as to determine whether the selecting element selects the first input signal or the second input signal;
• and
• an input terminal;
• a plurality of first storage elements, each of the first storage elements for receiving an input data, wherein an output terminal of each of the first storage elements is coupled to an input terminal of a next first storage element and also coupled to the first input terminal of a corresponding one of the plurality of selecting elements, for sending an input data received by a first input terminal to the corresponding selecting element as a first input signal;
• a plurality of second storage elements, each of the second storage elements for receiving an enable control signal, wherein an output terminal of each of the second storage elements is coupled to an input terminal of a next second storage element and also coupled to an enable control signal receiving terminal of a corresponding one of the plurality of selecting elements, for sending an enable control signal received by the second storage element to the corresponding selecting element;
• and
• a plurality of third storage elements, wherein an input terminal of each of the third storage elements is coupled to an output terminal of a corresponding selecting element, for outputting a data selected by the corresponding selecting element and feeding back the data signal output by the selecting element to a second input terminal of the selecting element so as to be selected as a second input signal for outputting a next set of data signals,
• wherein bits of an input data signal stream are input into the first storage elements sequentially and can be output at once as soon as having received the input data signal, without waiting for all the data are written in the plurality of first storage elements.

A method for serial to parallel of an input/output circuit system outputs an input data at once without waiting for the serial to parallel input/output circuit system to finish a writing of all the input data, comprising the steps of:

• inputting an input data, wherein the input data is one bit of an input data stream, and the input data stream is input into a serial to parallel input/output circuit system sequentially and each time one bit of the input data is input;
• inputting an enable control signal, wherein:
• when the enable control signal is of a first level, the serial to parallel input/output circuit system selecting the input data as its output;
• and
• when the enable control signal is of a second level, the serial to parallel input/output circuit system selecting a feedback data as its output;
• and
• outputting a data from the input data or the feedback data according to the enable control signal.