Portable storage medium based on universal serial bus standard and UFI standard

• US 6,757,783 B2
• Filed: 11/28/2001
• Issued: 06/29/2004
• Est. Priority Date: 11/13/2001
• Status: Expired due to Fees

• Current Assignee: Gsinstruments Company Limited
• Original Assignee: Daesung EC&P Co., Ltd.
• Inventors: Koh, Young Sook
• Primary Examiner(s): Sparks, Donald
• Assistant Examiner(s): Peugh, Brian R.
• Application Number:
  US09/996,219
• Publication Number:
  US 20030167376A1
• Time in Patent Office: 944 Days
• Field of Search: 711/103, 711/115, 711/137, 711/140, 711/107, 711/169, 711/133, 711/134, 711/141, 711/142, 711/143, 711/146, 711/154, 711/159, 710/105, 710/106, 710/313, 710/315
• US Class Current: 711/115
• CPC Class Codes: G06F 3/0601 Interfaces specially adapted for storage systems
• CPC Class Codes: G06F 3/0664 at device level, e.g. emulation of a storage device or system
• CPC Class Codes: G06K 19/077 Constructional details, e.g. mounting of circuits in the carrier
• CPC Class Codes: G06K 19/07732 the record carrier having a housing or construction similar to well-known portable memory devices, such as SD cards, USB or memory sticks housings for electrical equipment in general, see H05K5/02

Abstract

There is provided a portable storage medium, based on USB standard, connected to a USB port of a host computer applying UFI protocol. The portable storage medium comprises a USB connector through which the storage medium is physically connected to the USB port of the host computer; at least one nonvolatile flash memory for storing data transmitted from the host computer; a program storage for storing a predetermined operation program based on USB and UFI; and a controller for controlling the entire operation of the storage medium based on the operation program stored in the program storage. The operation program of the program storage includes a memory processing block for checking and updating header block information of the flash memory, a device recognition processing block for transmitting device descriptor information and interface descriptor information for loading a UFI driver to the host computer, and a UFI processing block for generating predetermined UFI response packets by UFI commands sent from the host computer to transmit them to the host computer.

Claims

1. A portable storage medium, based on USB standard, connected to a USB port of a host computer applying UFI protocol, comprising:

a USB connector through which the storage medium is physically connected to the USB port of the host computer;

at least one nonvolatile flash memory for storing data transmitted from the host computer;

a program storage for storing a predetermined operation program based on USB and UFI; and

a controller for controlling the entire operation of the storage medium based on the predetermined operation program stored in the program storage,

wherein the predetermined operation program of the program storage includes a memory processing block for checking and updating header block information of the flash memory, a device recognition processing block for transmitting device descriptor information and interface descriptor information for loading a UFI driver to the host computer, and a UFI processing block for generating predetermined UFI response packets by UFI commands sent from the host computer to transmit them to the host computer.

2. The portable storage medium as recited in claim 1, wherein the flash memory is a NAND type flash memory, and the storage medium includes a USB controller for transmitting and receiving data to and from the host computer based on USB standard, an SMC controller for controlling the operation of the flash memory using an SMC interface signal, and a microprocessor connected to the USB controller and SMC controller to control the operation of the USB controller and SMC controller based on the predetermined operation program of the program storage and a UFI command transmitted from the host computer.

3. The portable storage medium as recited in claim 2,

wherein the SMC controller is connected to the flash memory through a data/address bus to transmit data read or written and address information of the data;

wherein the program storage includes a memory driving block for selectively driving the flash memory based on memory address information contained in “

write” and

“

read”

commands transmitted from the host computer; and

wherein the microprocessor is connected to the flash memory through a system bus to apply a chip select signal for driving the flash memory according to the operation routine of the memory driving block.

4. The portable storage medium as recited in claim 1, wherein the program storage further includes a write processing block, the write processing block directly writing data in pages into a current memory address, when at least two “

write”

commands are sequently transmitted from the host computer for the same memory block of the flash memory, and when the memory address of a first “

write”

command, transmitted after a second “

write”

command of a corresponding memory block, follows the memory address of an immediate previous “

write”

command.

5. The portable medium as recited in claim 1, further comprising:

a toggle switch for operating a low-level-formatting operation when FAT information of the flash memory is damaged;

wherein the program storage further includes a format processing block for deleting a block 0 of the flash memory when the number of times of switching operations of the toggle switch exceeds a predetermined number of times.

6. A method for controlling the recognition of a portable storage medium which is connected to a USB port of a host computer applying UFI protocol and USB standard, the method comprising the steps of:

transmitting device descriptor information, containing a manufacturer ID, a product ID and a first class information for selecting a UFI method, to the host computer in response to a request of the device descriptor of the host computer;

transmitting interface descriptor information, containing a second class information for selecting UFI protocol, to the host computer in response to a request of the interface descriptor of the host computer;

loading a UFI driver of the host computer according to the selected UFI protocol;

transmitting a UFI response packet, including predetermined device information and capacity information, to the host computer in response to a request of identifying device and capacity of the host computer; and

sending FAT information stored in a flash memory to the host computer in response to a request of FAT information of the host computer.

7. A method for controlling data writing operation of a portable storage medium adapting USB standard, comprising:

a first step of confirming if a “

write”

command is transmitted from a host computer to which the storage medium is connected;

a second step of confirming if a transmitted “

write”

command is a first “

write”

command;

a third step of confirming if the memory address of a current “

write”

command follows the memory address of a previous “

write”

command, when the transmitted “

write”

command is not the first “

write”

command; and

a fourth step of writing a new page, after a previous page, when the memory address of a previous “

write”

command follows the memory address of a current “

write”

command,

the first to fourth steps being performed in a memory block where pages into which data will be written and pages into which data was written exist concurrently.

8. The method as recited in claim 7, wherein a general writing method of NAND type flash memory is executed, if the transmitted “

write”

command is identified as the first “

write”

command in the second step.

9. The method as recited in claim 8, wherein the general writing method of the NAND type flash memory is executed, if it is confirmed that the memory address of the current “

write”

command does not follow the memory address of the previous “

write”

command in the third step.

10. The method as recited in claim 7, wherein the first to fourth steps are repeated until writing of all a pages in a corresponding block is completed.