US 2001/0055232 A1 · Serial access memory and data write/read method

Abstract

There is provided a serial access memory and a data writeread method applicable thereto. The serial access memory is able to function as the prior art FIFO type serial access memory and as the prior art line access type serial access memory, too. This serial access memory 101 is provided with a memory cell array 11, a write register group 17, a read register group 20, and a writeread register group 32. The write/read register group 32 is made up of write/read registers WRreg-1 to WRreg-m. These write/read registers are prepared by the same number as that of memory cells (m pieces) connected with each of word lines WL1 to WLn, in the same way as the write registers Wreg-1 to Wreg-m forming the write register group 17 and the read registers Rreg-1 to Rreg-m forming the read register group 20.

Claims18

Dependent claims

A serial access memory comprising:

a plurality of memory cells which are arranged at each of intersections formed by a plurality of word lines and a plurality of bit lines;
the first register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines, and after storing an input serial data of one word, transferring said stored one word data to plural memory cells connected with one word line selected from among said plural word lines;
the second register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines, receiving the storage data of one word transferred from said plural memory cells connected with one word line selected from among said plural word lines, and outputting said transferred one word data as an output serial data of one word;
and
the third register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines, and after storing an input serial data of one word, outputting it as an output serial data of one word.

2 more elements

A data write/read method applicable to a serial access memory which includes:

a plurality of memory cells which are arranged at each of intersections made by a plurality of word lines and a plurality of bit lines,
the first register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines,
the second register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines, and
the third register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines,
said write/read method comprising:
the first write step of storing an input serial data of one word in said first register and said third register as well;
the second write step of transferring the one word data stored in said first register according to said first write step, to the plural memory cells connected with one word line selected from among said plural word lines;
the third write step of storing, in the first register, an input serial data of one word next to the input serial data of one word stored in said first register and said third register as well according to said first write step;
and
the fourth write step of transferring the one word data stored in said first register according to said third write step, to the plural memory cells connected with the other word line selected from among said plural word lines.

7 more elements

A data write/read method applicable to a serial access memory which includes:

a plurality of memory cells which are arranged at each of intersections made by a plurality of word lines and a plurality of bit lines,
the first register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines,
the second register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines, and
the third register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines,
said write/read method comprising:
the first write step of storing an input serial data of one word in said first register;
the second write step of transferring the one word data stored in said first register according to said first write step, to the plural memory cells connected with one word line selected from among said plural word lines as well as to said third register;
the third write step of storing in the first register an input serial data of one word next to the input serial data of one word stored in said first register according to said first write step;
and
the fourth write step of transferring the one word data stored in said first register according to said third write step, to the plural memory cells connected with the other word line selected from among said plural word lines.

7 more elements

A data write/read method applicable to a serial access memory which includes:

a plurality of memory cells which are arranged at each of intersections made by a plurality of word lines and a plurality of bit lines,
the first register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines,
the second register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines, and
the third register having a capacity capable of storing a data of one word to be stored in said plural memory cells connected with each of said plural word lines,
said write/read method comprising:
the first write step of storing an input serial data of one word in said first register;
the second write step of transferring the one word data stored in said first register according to said first write step, to said third register;
the third write step of storing in the first register an input serial data of one word next to the input serial data of one word stored in said first register according to said first write step;
the fourth write step of transferring the one word data stored in said first register according to said third write step, to the plural memory cells connected with one word line selected from among said plural word lines;
the fifth write step of storing in the first register an input serial data of one word next to the input serial data of one word stored in said first register according to said third write step;
and
the sixth write step of transferring the one word data stored in said first register according to said fifth write step to the plural memory cells connected with the other word line selected from among said plural word lines.

9 more elements

A data write/read method applicable to a serial access memory which includes:

a plurality of memory cells which are arranged at each of intersections made by a plurality of word lines and a plurality of bit lines,
the first register having a capacity capable of storing a data of one word (m bits) to be stored in said plural memory cells connected with each of said plural word lines,
the second register having a capacity capable of storing a data of one word (m bits) to be stored in said plural memory cells connected with each of said plural word lines, and
the third register having a capacity (p bits) smaller than the capacity capable of storing a data of one word (m bits) to be stored in said plural memory cells connected with each of said plural word lines,
said write/read method comprising:
the first write step of storing the first bit through the pth bit of an input serial data of one word in said third register;
the second write step of storing the (p+1)th bit through the mth bit of said input serial data of one word in said first register;
the third write step of transferring the (p+1)th bit through the mth bit of the data stored in said first register according to the second write step, to the plural memory cells connected with one word line selected from among said plural word lines;
the fourth write step of storing, in the first register, an input serial data of one word next to the input serial data of one word stored in said third register as well as in said first register according to said first write step and said second write step;
and
the fifth write step of transferring the one word data stored in said first register according to said fourth write step, to the plural memory cells connected with a word line other than said one word line.

8 more elements

Dependencies are inferred from the claim text.

Serial access memory and data write/read method

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Serial access memory and data write/read method

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Abstract

Claims18