US 6,581,843 B2 · Record medium and data transferring method using nonvolatile memory

Abstract

A data transferring method for a nonvolatile memory composed of a flash memory. The flash memory allows a gaplessly read process to be performed unless a transfer error takes place. The flash memory comprises a first shift register, a second shift register, and a switching circuit. The first shift register stores data of the first half area of one page for a data re-transfer process in the case that a transfer error takes place. The second shift register stores data of the second half area of one page for a data re-transfer process in the case that a transfer error takes place. The switching circuit switches between output data of a memory cell array and output data of the first and second shift registers. As a result, data can be transferred at the logically maximum speed. In addition, a transfer error is detected page by page. When a transfer error is detected, the data re-transfer process is performed using the shift registers. Thus, the throughput can be suppressed from deteriorating.

Claims7

Dependent claims

A record medium composed of a nonvolatile memory, the nonvolatile memory having a nonvolatile memory cell array that is accessible page by page, a controlling portion for controlling the nonvolatile memory cell array, and an input/output portion for connecting the nonvolatile memory to an external device, the record medium comprising:

latching means for latching data for one page that is read from the memory cell array;
a shift register for storing data that is output from said latching means for a data re-transfer process in the case that a transfer error is detected;
switching means for switching between output data of said latching means and output data of said shift register;
and
controlling means for transferring data for each page that is output from the memory cell array through said switching means to the external device through the input/output portion, determining whether or not a transfer error takes place in the transferred data, and performing the data re-transfer process for the data when a transfer error takes place in the transferred data,
wherein when the transfer error does not take place in the transferred data, said switching means is controlled so that output data of said latching means is transferred to the external device, and
wherein when the transfer error takes place in the transferred data and the data re-transfer process is performed for the transferred data, said switching means is controlled so that the data for one page stored in said shift register is transferred to the external device.

4 more elements

first latching means for latching data of the first half area of one page read from the memory cell array;
second latching means for latching data of the second half area of one page read from the memory cell array;
controlling means for controlling a read process of the memory cell array in such a manner that while data of the first half area of one page or data of the second half area of one page is being transferred, data of the second half area of one page or data of the first half area of one page is accessed;
a first shift register for storing data that is output from said first latching means for a data re-transfer process in the case that a transfer error is detected;
a second shift register for storing data that is output from said second latching means for the data re-transfer process in the case that a transfer error is detected;
switching means for switching between output data of said first latching means and said second latching means and output data of said first shift register and said second shift register;
and
controlling means for transferring data for each page that is output from the memory cell array through said switching means to the external device through the input/output portion, determining whether or not a transfer error takes place in the transferred data, and performing the data re-transfer process for the data when a transfer error takes place in the transferred data,
wherein when the transfer error does not take place in the transferred data, said switching means is controlled so that output data of said first latching means and said second latching means is transferred to the external device, and
wherein when the transfer error takes place in the transferred data and the data re-transfer process is performed for the transferred data, said switching means is controlled so that the data of the first half area of one page stored in said first shift register and the data of the second half area of one page stored in said second shift register are transferred to the external device.

7 more elements

first latching means for latching data of the first half area of one page read from the memory cell array;
second latching means for latching data of the second half area of one page read from the memory cell array;
controlling means for controlling a read process of the memory cell array in such a manner that while data of the first half area of one page or data of the second half area of one page is being transferred, data of the second half area of one page or data of the first half area of one page is accessed;
a shift register for storing data that is read from said first latching means for a data re-transfer process in the case that a transfer error is detected;
switching means for switching between output data of said first latching means and said second latching means and output data of said shift register;
and
controlling means for transferring data for each page that is output from the memory cell array through said switching means to the external device through the input/output portion, determining whether or not a transfer error takes place in the transferred data, and performing the data re-transfer process for the data when a transfer error takes place in the transferred data,
wherein when the transfer error does not take place in the transferred data, said switching means is controlled so that output data of said first latching means and said second latching means is transferred to the external device, and
wherein when the transfer error takes place in the transferred data and the data re-transfer process is performed for the transferred data, said switching means is controlled so that the data of the first half area of one page stored in said shift register and the data of the second half area of one page stored in said second latching means are transferred to the external device.

6 more elements

A data transferring method for a record medium composed of a flash memory for dividing a nonvolatile memory cell array that is accessible page by page into a first half area of one page and a second half area of one page and performing a gapless read process in such a manner that while data of the first half area of one page or data of the second half area of one page is being transferred, data of the second half area of one page or data of the first half area of one page is accessed, the method comprising the steps of:

accessing the data of the first half area of one page from the memory cell array and latching the data of the first half area of one page to first latching means;
transferring the data of the first half area of one page from the first latching means to an external device, storing the data of the first half area of one page to a first shift register for a data re-transfer process in the case that a transfer error is detected, accessing the data of the second half area of one page from the memory cell array, and latching the data of the second half area of one page to second latching means;
after the data of the first half area of one page has been transferred, transferring the data of the second half area of one page to the external device, storing the data of the second half area of one page to a second shift register for a data re-transfer process in the case that a transfer error is detected, and accessing data of the first half area of the next page from the memory cell array;
after the data of the first half area of one page and the data of the second half area of one page have been transferred to the external device, determining whether or not a transfer error takes place in the data for one page transferred to the external device;
when the transfer error is not detected, reading and transferring data for the next page;
and
when the transfer error is detected, transferring the data of the first half area of one page stored in the first shift register to the external device and transferring the data of the second half area of one page stored in the second shift register to the external device.

4 more elements

accessing the data of the first half area of one page from the memory cell array and latching the data of the first half area of one page to first latching means;
transferring the data of the first half area of one page from the first latching means to an external device, storing the data of the first half area of one page to a shift register for a data re-transfer process in the case that a transfer error is detected, accessing the data of the second half area of one page from the memory cell array, and latching the data of the second half area of one page to second latching means;
after the data of the first half area of one page has been transferred, transferring the data of the second half area of one page to the external device and accessing data of the first half area of the next page from the memory cell array;
after the data of the first half area of one page and the data of the second half area of one page have been transferred to the external device, determining whether or not a transfer error takes place in the data for one page transferred to the external device;
when the transfer error is not detected, transferring data for the next page;
and
when the transfer error is detected, transferring the data of the first half area of one page stored in the first shift register to the external device and transferring the data of the second half area of one page latched in the second latching means to the external device.

4 more elements

Dependencies are inferred from the claim text.

Record medium and data transferring method using nonvolatile memory

Life of this patent

Record medium and data transferring method using nonvolatile memory

Life of this patent

Abstract

Claims7