Method and an apparatus of flash cards access

Abstract

A method for flash cards access is provided, said method comprises detecting signals from specific pins of slots of flash cards and determining flash card insertion according to said signals. Said method further comprises disabling flash cards by sending signals for at least one pin of other flash cards' slots.

Description

FIELD OF INVENTION

The invention is a method related to accessing flash card memory, and more particularly is a method, which allows the insertion of a second type of flash card memory without interference to a first type flash card memory that is accessing data.

BACKGROUND

With the wide spread of consumer wireless multimedia electronic devices, there is an increasing demand for mobile storage. The great varieties of memory card type products are expected to take place in the near future as the mainstream data storage platform. Compact, large storage capacity, quick accessing time for both read and write, low power consumption, good vibration resistance, therefore very suitable for carrying around. The more commonly seen portable memory devices include compact flash cards (CF card), smart media card (SM card), memory stick (MS), multi media card (MMC) and secure digital card (SD card). These flash card memories all come with a set of specification and are incompatible with each other. Therefore the devices each standard support and available accessories have become a crucial determinant for its success in the consumer market. It is not challenging technically to support a single memory card standard; however, to satisfy the current trend of consumer demand, a device integrated with slots to adapt various flash memory card accessing is necessary.

Please refer to FIG. 1. FIG. 1 illustrates device used presently to read flash memory cards of multiple standards. As shown, the device consists of a flash card interface 110, bus 120 and a control device 130. Flash card interface 110 further comprises plurality of slots suitable for various types of flash memory cards. The pins are connected to the control device 130 via bus 120. The control device could be a chip.

Users of this known device inserts a first flash memory card to a compatible flash card interface 110 and control device 130 determines the specific type of the flash card inserted via signals received from bus 120. The card is then activated and able to be accessed. If a second flash memory card is inserted, control device 130, lacking mechanism to disable this second card, will repeat the same process with the first card, detect the second card and activate the second card. The activation of the second card will affect accessing the first flash memory card.

SUMMARY OF INVENTION

The present invention is a method which ensures data accessing of a flash memory card unaffected when a second flash memory card of different type is inserted. To be more specific, the method makes sure that while accessing an inserted flash memory card, the insertion and activation of a second flash memory card will not have an affect on the interaction of the device and the first memory card.

The present invention is a method which ensures data accessing of a flash memory card unaffected when a second flash memory card of different type is inserted. The method contains at least the following steps; detecting signals from specific pins of the plurality of slots, using the said signal to determine which slot the memory card was inserted to, and send signal to the disable pin of other slots to disable those slots.

The present invention is a method which ensures data accessing of a flash memory card unaffected when a second flash memory card of different type is inserted. The apparatus related to the method includes a detecting module which detects and determines which slot the card was inserted to; a data accessing module, which access data from the inserted flash memory card; and a disable module that disables the activation flash memory cards inserted to other slots.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows prior implementation of multiple flash memory card accessing devices.

FIG. 2 illustrates the best embodiment of the present invention relating to multiple flash memory card accessing device.

FIG. 3 show another best embodiment of the present invention relating to multiple flash memory card access device.

FIG. 4 describes steps of the present invention for accessing flash memory cards

FIG. 5 demonstrates the connection between flash memory card slots for the best embodiment of present invention

DETAILED DESCRIPTION OF THE INVENTION

To further explain the features and techniques related to the present invention, please follow description with reference to picture below. The following description intends to present the present invention within the context of a particular application and its requirement. Various modifications to the preferred will, however, be apparent to one skilled in the art, and the general principles defined herein may be applied to other embodiments. Therefore, the present invention is not intended to be limited to the particular embodiment shown and described herein, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed.

Now please turn to FIG. 2. FIG. 2 shows a preferred embodiment of the present invention. The diagram includes a flash memory card interface 210, a bus 220 and a control device 230. The flash memory card interface 210 has a plurality of slots that interfaces with different types of cards. The pins found in the slots are connected to bus 220. Signals received by these pins are transmitted to control device 230 via bus 220. Control device 230 contains a detection module 231 for determining which type of flash card is inserted into the slot, a data access module 232 for reading and writing data to the flash memory card and a disabling module 233 that disables flash cards inserted other slots when there is a first card in one of the slots in order to prevent flash memory cards in these slots from initializing.

There are several methods to send control signals to the card disabling pins in the slots; the detection module 231 detects a card being inserted from the signal change of the pins. If inserted card is the first flash memory card inserted to the device, signals will be sent to initialize the card for data access. Disabling module 233 will send signals to the disabling pins of other flash memory card slots to disable all other flash memory cards.

Please refer to FIG. 3. FIG. 3 illustrates one of the better modes of embodiment of the invention. The embodiment includes a flash memory card interface 310, a bus 320 and a control device 330. The flash memory card interface further includes slots for varies types of flash memory cards. The pins of these slots are connected to bus 320, which means the pins from the various slots uses a common circuitry. This means there are fewer connections required and therefore the cost for production is lower and surface required is smaller. Pins C, D for detecting whether a flash memory card is inserted and pin E for enabling flash memory card are exceptions; these pins do not connect with their counterparts from other slots. Control module further comprises a detection module 331 for detecting the insertion of a flash memory card; an access module 332 for accessing data stored in the flash memory card and a disabling module 333 to initialize flash memory card. Disabling module 333 send signal to pin E of the first inserted flash memory card and enable it for data accessing. The module also send out disabling signal to pin E of other flash memory cards to disable those cards. This disabling procedure prevents any interruption that may occur during data transmission caused by other flash memory cards transmitting signals to the shared bus.

Please turn to FIG. 4. FIG. 4 illustrates steps taken by the present invention to access data from a flash memory card, including;

• • Step 41: Scan for signals from flash memory card slot pins;
  • Step 42: Detect the insertion of a flash memory card from the signals
  • Step 43: Commence accessing data from the flash memory card; and
  • Step 44: Send out signals to disable other flash memory card slots to disable other cards.
    Please refer to FIG. 5. FIG. 5 describes the pins of present invention's embodiment. The table summarizes the pin assignment of five types of flash memory cards. The table further describes which pins of the different flash memory cards are joined together. For example, the third pin of SD/MMC card are assigned as the SDD1 pin and it is joint with the CF card's CFD2 and SM card's SMD4.

The present embodiment prevents flash memory cards from interrupting the data accessing of the first flash memory card by;

1. When a CF Card is Being Accessed

• • SMCE_ pin of SM card is pulled high to keep SM card from being initialized and remains inactive. The CFREST of CF card is a reset pin, normally it would remain pulled up or pulled down, however according to FIG. 5, CFREST signal line is connected to the SDCLK signal line of MMC and SD card, as well as the MSCLK signal line of the MS card. This means SDCLK and MSCLK will be pulled high or low together constantly and will not be activated since there is no transition.

2. When SM card is being accessed

• • Please refer to FIG. 5. The table shows that the CFRESET of CF card, CFCS1 and CFCS2 of SM card are not connected. The CFREST is a reset pin, and the CFCS1 and CFCS2 are control pins. An active SM card will set CFREST, CFCSO and CFCS1 high and therefore the CF card would not be reset and the control pins are not enabled. In other words, the CF card will not be activated. The SDCLK of SM card and MSCLK of the MS card the MSCLK of MS card are connected to the CF card's CFRESET signal line. As the SDCLK and MSCLK will be pulled high, there will be no transition to activate or enable the SM and MS cards.

3. When SD/MMC Card are Being Accessed

• • Please refer to FIG. 5. None of the SD/MMC pins are connection to the CFCS0 and CFCS1 of the CF card. CFCS0 and CFCS1 are the control pins of CF card. When SD or MMC cards are being accessed, CFCS0 and CFCS1 are being pulled high, the CF card control pins remain inactive and the CF card is not activated. The SD/MMC card slot pins are not connected with the enable pin of the SM card SMCE_. SM card is activated by passing a low voltage to the SMCE_ pin. However, while SD/MMC card are active, the SMCE_ receives constant high voltage; therefore, the SM card is never activated. On the other hand, the MS card and the SD/MMC card do not share any common connection.

4. When MS Card are Being Accessed

• • Please refer to FIG. 5. MS card does not share connection with CF cards CFCS0 and CFCS1. The CFS0 and CFS1 are the control pins of CF cards. While MS card is activated, CFS0 and CFSC1 continue to be pulled high. The CF card will not be activated as there is no control signal received at any of the pins. CF card remains disabled. MS card and SM card's enable pin, SMCE_, are not connected. SM card is activated when its SMCE_ pin receives a low input. However, while MS card is active, it consistently sends high voltage to the SMCE_ corresponding pin, so the SM card is never activated. On the other hand, the SD/MMC card pins share no connections with the MS card and SD/MMC card enable pin, SDCMD, is set low while MS is active, so SD/MMC card will not be enabled.

The present invention provides a method for accessing flash memory card. More particularly, the present invention is used for accessing multiple types of flash memory cards. As signal is received from a particular pin of a first flash memory card, the said first memory card is enabled and ready to be accessed. Disabling signal is sent to all other flash memory card pins so that other flash memory cards will not be enabled and accessed. While the first flash memory card in a multiple flash memory card reader is being accessed, any other flash memory card inserted to the card reader will not affect the operation with the first memory card.

The above-described embodiments of the invention are given to better illustrate the principals of the present invention. Alternative embodiments may be devised by those skilled in the art without departing from the spirit and scope of the following claims.

Claims

1. A method for accessing flash memory card, comprising

detecting at least one signal from at least one pin belonging to a plurality of flash memory card slots,

determining the type of flash memory card inserted base on said signals,

sending at least one control signal to at least one disable pin of any other memory card slots to disable any other memory cards.

2. The method as recited in claim 1, wherein methods for sending at least one control signal to at least one disable pin of any other memory card slots to disable any other memory cards is achieved by one of the following:

sending a control signal to at least one disable pin of other memory card slots after detecting the insertion of a first memory card; and

monitoring for signals from slots other than the first memory card slot after the insertion of a first memory card is detected, and then sending out a control signal to the second memory card slot to disable the card that is inserted after the first memory card is detected.

3. The method as recited in claim 2, when the first flash memory card inserted is Compact Flash card, send at least one control signal to at least one disable pin of other slots to disable flash memory cards inserted to slots other than the first memory card slot, the inserted memory card could be any of the following type: Compact flash card, smart media card, secure digital card/multi media card and memory stick card.

4. The method as recited in claim 2, when the first flash memory card inserted is Smart Media card, send at least one control signal to at least one disable pin of other slots to disable flash memory cards inserted to slots other than the first memory card slot, the inserted memory card could be any of the following type: Compact Flash card, Smart Media Card, Secure Digital Card/Multi Media Card and Memory Stick Card.

5. The method as recited in claim 2, when the first flash memory card inserted is Secure Digital/Multi Media card, send at least one control signal to at least one disable pin of other slots to disable flash memory cards inserted to slots other than the first memory card slot, the inserted memory card could be any of the following type: Compact Flash card, Smart Media Card, Secure Digital Card/Multi Media Card and Memory Stick Card.

6. The method as recited in claim 2, when the first flash memory card inserted is Memory Stick card, send at least one control signal to at least one disable pin of other slots to disable flash memory cards inserted to slots other than the first memory card slot the inserted memory card could be any of the following type: Compact Flash card, Smart Media Card, Secure Digital Card/Multi Media Card and Memory Stick Card.

7. The method as recited in claim 2, wherein control signal is sent to pin CFRESET of other memory card slots to pull pin CFRESET high continuously, such that the any CF card inserted in other slots will not be enabled.

8. The method as recited in claim 2, wherein control signal is sent to CFCS0 and CFCS1 to pull CFCS0 and CFCS1 high continuously, such that CFCS0 and CFCS1, CFCS0 and CFCS1 cannot control other pins of the CF card and therefore CF cards in other slots are not enabled.

9. The method as recited in claim 2, wherein control signal is sent to pull SMCE_ of other slots high continuously to prevent SM cards in any other slots from being enabled.

10. The method as recited in claim 2, wherein control signal is sent to pull SDCLK of other slots continuously high or low, such that the SD card inserted other slots are not enabled.

11. The method as recited in claim 2, wherein control signal is sent to pull SDCMD pin of other slots continuously high so that SD cards in other slots will not receive signal to activate and remains disabled.

12. The method as recited in claim 2, wherein control signal is sent to pull MSCLK continuously high or continuously low; MS cards in other slots remain disabled since there is no transition at pin MSCLK.

13. The method as recited in claim 2, wherein control signal is sent to pull MSBS of other slots continuously high so that MS cards in other slots will not receive signal to activate and remains disabled.

14. A device which operates unaffected by the insertion of other types of flash memory cards comprising;

a detection module which detects the insertion of a first flash memory card into a flash memory card slot;

an accessing module which access data in said first flash memory card; and

a disabling module which disables at least one flash memory card inserted on other than said first flash memory card.

15. The device as recited in claim 14, wherein the kind of the inserted first flash memory card type is determined by where the detected signal is from; that is the pin and the slot of the signal origin is used to determine the card type.

16. The device as recited in claim 14, wherein the disabling module send signals to particular pins in slots other than the one with said first flash memory card to disable any flash memory cards inserted in other than said first flash memory card.

17. The device as recited in claim 14, wherein the device further comprises a bus between flash memory card interface and said modules for transferring data between the accessing module and the flash memory card interface.

18. The device as recited in claim 14, wherein the device further comprises a flash memory card device for connecting flash memory card and the bus.

19. The device as recited in claim 14, wherein the flash memory card interface consists of at least two flash memory card slots.

20. The device as recited in claim 14 wherein pins of different slots for transferring data in flash memory cards are interconnected