Memory card type identification method

Abstract

A method for identifying the type of a memory card, wherein the pin numbering of the memory card conforms to a memory card specification defined by the Security Digital Association, the method comprising: performing a conventional memory card initialization procedure on the memory card; and sequentially determining whether the memory card is a Security Digital Fast Card, a Type II Ultra-High Speed ​​Security Digital Card, or a conventional memory card.

Description

Technical Field

[0001] This invention relates to Secure Digital (SD) memory cards, and more particularly to SD card reader devices, electronic devices, and methods for identifying SD card types. Background Technology

[0002] Currently, the most common secure digital memory cards are of three types: traditional SD cards, SD cards supporting the Peripheral Component Interconnect Express (PCIe) interface (i.e., SD Express cards), and SD cards supporting the Ultra High Speed ​​type II (UHS-II) interface (UHS-II SD cards). Both SD Express and UHS-II SD cards are backward compatible with traditional SD cards. However, because SD Express and UHS-II SD cards have identical signal contact point arrangements, but the PCIe interface is AC-coupled while the UHS-II interface is DC-coupled, identifying SD Express and UHS-II SD cards is not easy, causing considerable inconvenience to users. Furthermore, if a card reader is to also backward support traditional SD cards, recognizing the type of memory card becomes an even greater challenge.

[0003] Therefore, a method for identifying SD card types is needed. Summary of the Invention

[0004] In view of the shortcomings of the prior art, one object of the present invention is to provide a method for identifying SD card types, so as to improve the shortcomings of the prior art.

[0005] An embodiment of the present invention provides a method for identifying the type of a memory card, used to identify the type of a secure digital card, wherein the pin numbering of the secure digital card conforms to a secure digital card specification formulated by the Secure Digital Association. The method includes: performing one of a Type II Ultra-High Speed ​​Secure Digital Card initialization procedure and a Secure Digital Fast Card initialization procedure on the secure digital card; controlling a pin numbered 4 of the secure digital card to be substantially 0 volts; controlling a pin numbered 14 of the secure digital card to be substantially 0 volts; performing the other of the Type II Ultra-High Speed ​​Secure Digital Card initialization procedure and the Secure Digital Fast Card initialization procedure on the secure digital card; and determining whether the secure digital card is a Type II Ultra-High Speed ​​Secure Digital Card or a Secure Digital Fast Card.

[0006] Another embodiment of the present invention provides a memory card type identification method for identifying the type of a secure digital card, wherein the pin numbering of the secure digital card conforms to a secure digital card specification formulated by the Secure Digital Association. The method includes: performing a conventional secure digital card initialization procedure on the secure digital card; and sequentially determining whether the secure digital card is a secure digital fast card, a second-class ultra-high-speed secure digital card, or a conventional secure digital card.

[0007] Another embodiment of the present invention provides a memory card type identification method for identifying the type of a secure digital card, wherein the pin numbering of the secure digital card conforms to a secure digital card specification formulated by the Secure Digital Association. The method includes: performing a Type II Ultra-High Speed ​​Secure Digital Card initialization procedure on the secure digital card; determining whether the secure digital card is a Type II Ultra-High Speed ​​Secure Digital Card; when the secure digital card is not a Type II Ultra-High Speed ​​Secure Digital Card, controlling pin 4 of the secure digital card to be substantially 0 volts and pin 14 of the secure digital card to be substantially 0 volts; and performing a conventional secure digital card initialization procedure on the secure digital card; determining whether the secure digital card is a Secure Digital Fast Card; and when the secure digital card is not a Secure Digital Fast Card, determining whether the secure digital card is a conventional secure digital card.

[0008] Compared to existing technologies, the invented memory card type identification method can identify at least SD Express cards, UHS-II SD cards, and traditional SD cards.

[0009] The features, implementation, and technical effects of this invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0010] Figure 1 This is a functional block diagram of an embodiment of the electronic device of the present invention;

[0011] Figure 2 Displays the pin numbers of the security digital card;

[0012] Figure 3 A flowchart showing an embodiment of the memory card type identification method of the present invention;

[0013] Figure 4 show Figure 3 A flowchart of an embodiment of step S11;

[0014] Figure 5 show Figure 3 A flowchart of an embodiment of step S21;

[0015] Figure 6 show Figure 3A flowchart of an embodiment of step S13;

[0016] Figure 7 show Figure 3 A flowchart of an embodiment of step S22;

[0017] Figure 8 show Figure 3 A flowchart of an embodiment of step S15;

[0018] Figure 9 show Figure 3 A flowchart of an embodiment of step S23;

[0019] Figure 10 A flowchart showing another embodiment of the memory card type identification method of the present invention;

[0020] Figure 11 show Figure 10 A flowchart of an embodiment of step S16;

[0021] Figure 12 A flowchart showing another embodiment of the memory card type identification method of the present invention;

[0022] Figure 13 show Figure 12 A flowchart of an embodiment of step S24;

[0023] Figure 14 show Figure 12 A flowchart of an embodiment of step S25;

[0024] Figure 15 show Figure 12 A flowchart of an embodiment of step S26;

[0025] Figure 16 A flowchart showing another embodiment of the memory card type identification method of the present invention; and

[0026] Figure 17 show Figure 16 A flowchart of an embodiment of step S27.

[0027] Symbol Explanation

[0028] 10A: Electronic devices

[0029] 20: SD card

[0030] 12: Chip

[0031] C1, C2: Capacitors

[0032] 11A: Card reader

[0033] 18: Memory card slot

[0034] S0, S1, S2, S4, S5, S7: Signals

[0035] P1, P3, P2, P4: Pins

[0036] 105: Selection Circuit

[0037] 120: Control Circuit

[0038] 130: Bridged card reader circuit

[0039] 135: UHS-II Physical Layer

[0040] S3: Control signal

[0041] Pa, Pb: Endpoints

[0042] S11, S12, S13, S14, S15, S16, S21, S22, S23, S24, S25, S26, S27, S31, S32, S33, S34, S35, S112, S114, S116, S118, S132, S134, S136, S138, S152, S154, S162, S164, S166, S212, S216, S218, S221, S223, S224, S225, S226, S227, S232, S234, S242, S244, S246, S252, S254, S262, S272, S274: Steps Detailed Implementation

[0043] The technical terms used in the following description are based on the customary terms in this technical field. If this specification provides explanations or definitions for certain terms, the explanations or definitions in this specification shall prevail.

[0044] The present invention discloses a card reader or electronic device supporting various SD cards, and a method for identifying SD card types. Since some components of the card reader and electronic device of the present invention may be known individually, details of known components will be omitted in the following description without affecting the full disclosure and implementability of the invention. Furthermore, part or all of the process of the method for identifying SD card types of the present invention may be in the form of software and / or firmware, and can be executed by the card reader of the present invention or its equivalent. Without affecting the full disclosure and implementability of the method invention, the following description of the method invention will focus on the steps rather than the hardware.

[0045] Figure 1This is a functional block diagram of an embodiment of the electronic device of the present invention. The electronic device 10A has a card reading function and can access an SD card 20. The electronic device 10A includes a chip 12, a capacitor C1, a card reader 11A, a capacitor C2, and a memory card slot 18. The card reader 11A is coupled between the chip 12 and the memory card slot 18. More specifically, the card reader 11A is coupled to the chip 12 via capacitor C1 and to the memory card slot 18 via capacitor C2. The memory card slot 18 is used to receive the SD card 20 (i.e., for inserting the SD card 20).

[0046] One end of capacitor C1 is coupled or electrically connected to chip 12, and the other end is coupled or electrically connected to card reader 11A. Capacitor C1 acts as an AC coupling capacitor. When the signal transmission direction is from chip 12 to card reader 11A, the signal S0 between chip 12 and capacitor C1 contains both AC and DC components, while the signal S1 between capacitor C1 and card reader 11A contains only the AC component and not the DC component. When the signal transmission direction is from card reader 11A to chip 12, signal S1 contains both AC and DC components, while signal S0 contains only the AC component and not the DC component. Because PCIe signals are transmitted through AC coupling, one of the purposes of capacitor C1 is to provide a PCIe signal connection between chip 12 and card reader 11A, that is, to establish a PCIe interface between chip 12 and card reader 11A.

[0047] One end of capacitor C2 is coupled or electrically connected to pin P1 of card reader 11A, and the other end of capacitor C2 is coupled or electrically connected to pin P3 of memory card slot 18. Capacitor C2 acts as an AC coupling capacitor. When the signal transmission direction is from memory card slot 18 to card reader 11A, signal S5 between pin P3 and capacitor C2 contains both AC and DC components, while signal S2 between capacitor C2 and pin P1 contains only the AC component and not the DC component. When the signal transmission direction is from card reader 11A to memory card slot 18, signal S2 may contain both AC and DC components, while signal S5 contains only the AC component and not the DC component. It is worth noting that when the signal transmitted between pin P1 and pin P3 is a PCIe signal, both signal S5 and signal S2 are PCIe signals.

[0048] The card reader 11A also includes pins P2 and P4. Pin P2 is coupled or electrically connected to pin P3, and pin P4 is coupled or electrically connected to at least one pin (not shown) of the memory card slot 18. When the SD card 20 is a conventional SD card, the card reader 11A accesses the SD card 20 at least through pin P4 (signal S7 is a signal conforming to the conventional SD card specification, hereinafter referred to as the conventional SD card signal). When the SD card 20 is a UHS-II SD card (in this case, signal S5 is a signal conforming to the UHS-II SD card specification, hereinafter referred to as the UHS-II SD card signal), the card reader 11A accesses the SD card 20 at least through pin P2, but not through pin P1. In this case, pin P1 becomes a sideband signal for auxiliary use, such as providing a clock or some control signals. When the SD card 20 is an SD Express card (at this time, signal S5 is the SD Express card signal), the card reader 11A accesses the SD card 20 at least through pin P1, but not through pin P2.

[0049] In some embodiments, chip 12, capacitors C1, C2, 11A and memory card slot 18 are disposed on the circuit board (not shown) of electronic device 10A, and the aforementioned signals S0, S1, S2, S5 and S7 are transmitted via traces on the circuit board or wires.

[0050] The card reader 11A includes a selection circuit 105 (e.g., a multiplexer, MUX), a control circuit 120, and a bridged card reader circuit 130. The control circuit 120 is coupled to the selection circuit 105 and the bridged card reader circuit 130 and is used to control the selection circuit 105 and the bridged card reader circuit 130.

[0051] The bridging card reader circuit 130 converts a conventional SD card signal (i.e., signal S7) into a PCIe signal (i.e., signal S4). The bridging card reader circuit 130 includes a UHS-II physical layer 135 used to convert UHS-II SD card signals (e.g., signal S5) into signal S4. In other words, the bridging card reader circuit 130 is a bridging card reader circuit for conventional SD cards and UHS-II SD cards. The bridging card reader circuits for conventional SD cards and UHS-II SD cards are well known to those skilled in the art, and therefore their details will not be elaborated upon. For the conventional SD card part, please refer to the Physical Layer Simplified Specification on the SD Association website https: / / www.sdcard.org / downloads / pls / ; and for the UHS-II part, please refer to the UHS-II Simplified Addendum.

[0052] Selection circuit 105 receives signals S2 and S4. Control circuit 120 controls selection circuit 105 via control signal S3. When SD card 20 is an SD Express card, control circuit 120 controls selection circuit 105 to select terminal Pa; that is, to form a path between capacitor C1 and pin P1 (i.e., signal connection: signal S1 = signal S2), and to form an open circuit between capacitor C1 and bridge card reader circuit 130 (i.e., no signal connection: signal S1 ≠ signal S4). When SD card 20 is a UHS-II SD card or a conventional SD card, control circuit 120 controls selection circuit 105 to select terminal Pb; that is, to form a path between capacitor C1 and bridge card reader circuit 130 (signal S1 = signal S4), and to form an open circuit between capacitor C1 and pin P1 (signal S1 ≠ signal S2).

[0053] When SD card 20 is an SD Express card, chip 12 accesses SD card 20 through the following path: When SD card 20 is a UHS-II SD card, chip 12 accesses SD card 20 through the following path: When SD card 20 is a traditional SD card, chip 12 accesses SD card 20 through the following path: In other words, the card reader 11A supports access to multiple SD cards, and the electronic device 10A using the card reader 11A has the ability to access multiple SD cards.

[0054] Figure 1 Chip 12 is connected to or communicates with card reader 11A via a PCIe interface; in other words, the presence of capacitor C1 ensures that the signal transmission between chip 12 and card reader 11A conforms to PCIe specifications. Therefore, in some embodiments, capacitor C2 can be omitted to save cost or circuit area.

[0055] Figure 2 This displays the pin numbers of the Secure Digital Card (SD card, UHS-II SD card, and SD Express card). These pin numbers conform to the Secure Digital Card specification defined by the Secure Digital Association (SDA). For a description of these pins and more details, please refer to the Physical Layer Simplified Specification on the SDA website: https: / / www.sdcard.org / downloads / pls / . Figure 2 The pin or signal names listed (such as clock RCLK+ / -, clock REFCLK+ / -, signal PERST#, CLKREQ#, etc.) can all be found in the Security Digital Card Specification for definitions or related implementation details.

[0056] exist Figure 1 In this embodiment, the control circuit 120 communicates with the SD card 20 (including but not limited to transmitting / receiving clock signals, commands, data, etc.) through pins P1, P2, P4 and / or other pins of the card reader 11A (not shown). For simplicity, Figure 1 The connections between these pins and the control circuit 120 and the memory card slot 18 are omitted.

[0057] Figure 3 A flowchart illustrating an embodiment of the memory card type identification method of the present invention is shown. This process can be executed by a card reader 11A and includes the following steps.

[0058] Step S11: Perform the UHS-II SD card initialization procedure on SD card 20. Details of step S11 will be provided below. Figure 4 Let's have a discussion.

[0059] Step S21: Determine whether SD card 20 is a UHS-II SD card. If the result is yes, proceed to step S31; otherwise, proceed to step S12. Details of step S21 will be provided below. Figure 5 Let's have a discussion.

[0060] Step S31: Continue the UHS-II SD card initialization procedure (see the Secure Digital Card Specification for details).

[0061] Step S12: Control pin 4 is essentially 0 volts (V) and control pin 14 is essentially 0V (i.e., equivalent to turning off pins 4 and 14). Note that "essentially a voltage" means equal to or approximately that voltage.

[0062] Step S13: Perform the SD Express card initialization procedure on SD card 20. Details of step S13 will be provided below. Figure 6 Let's have a discussion.

[0063] Step S22: Determine whether SD card 20 is an SD Express card. If the result is yes, proceed to step S32; otherwise, proceed to step S14. Details of step S22 will be provided below. Figure 7 Let's have a discussion.

[0064] Step S32: Continue with the SD Express card initialization procedure (see the Secure Digital Card Specification for details).

[0065] Step S14: Step S14 is the same as step S12.

[0066] Step S15: Perform the traditional SD card initialization procedure on SD card 20. Details of step S15 will be provided below. Figure 8 Let's have a discussion.

[0067] Step S23: Determine whether SD card 20 is a traditional SD card. If the result is yes, proceed to step S33; otherwise, proceed to step S34. Details of step S23 will be provided below. Figure 9 Let's have a discussion.

[0068] Step S33: Continue with the traditional SD card initialization procedure (see the Secure Digital Card Specification for details).

[0069] Step S34: Control pin 4 is actually 0V because SD card 20 is another type of memory card or not a memory card.

[0070] Figure 4 show Figure 3 A flowchart of an embodiment of step S11 includes the following steps.

[0071] Step S112: Control pin number 4 is actually 3.3V.

[0072] Step S114: Control pin number 14 to be 1.8V.

[0073] Step S116: Control pin 1 is essentially at a low voltage (e.g., 0V). Please refer to [link / reference]. Figure 2 Since the Secure Digital Card specification does not define pin number 1 in UHS-II mode, pin number 1 can be either high or low voltage for UHS-II mode. However, for PCIe mode, the SD Express card will not operate when pin number 1 (i.e., PERST#) is low voltage. Therefore, step S116 can prevent the SD Express card from being mistakenly identified as a UHS-II SD card.

[0074] Step S118: Control pins 9, 2, and 5 to be essentially at a low voltage (e.g., 0V). Please refer to [link / reference]. Figure 2 Since the Security Digital Card specification does not define pins 9, 2, and 5 in UHS-II mode, these three pins can be at high or low voltage for UHS-II mode. Note that in some embodiments, step S118 is optional.

[0075] Figure 5 show Figure 3 A flowchart of an embodiment of step S21 includes the following steps.

[0076] Step S212: Simultaneously provide clock RCLK+ to pin 7 and clock RCLK- to pin 8.

[0077] Step S216: Provide signal STB.L to pins 11 and 12. Please refer to the Security Digital Card specification for the definition or implementation details of signal STB.L.

[0078] Step S218: Determine whether the signal STB.L is detected at pins 15 and 16. If the determination result is yes, the control circuit 120 can determine that the SD card 20 is a UHS-II SD card; otherwise, the SD card 20 is not a UHS-II SD card.

[0079] Figure 6 show Figure 3 A flowchart of an embodiment of step S13 includes the following steps.

[0080] Step S132: Control pin number 4 to be 3.3V.

[0081] Step S134: Control pin number 18 to be 1.2V.

[0082] Step S136: Control pin 9 to be at a high voltage (e.g., 3.3V).

[0083] Step S138: Control pin number 1 is essentially at a low voltage (e.g., 0V).

[0084] Figure 7 show Figure 3 A flowchart of an embodiment of step S22 includes the following steps.

[0085] Step S221: Simultaneously provide clock RRFCLK+ to pin 7 and clock RRFCLK- to pin 8.

[0086] Step S223: Control pin 1 to be at a high voltage (e.g., 3.3V).

[0087] Step S224: Determine whether pin 9 is actually at a low voltage (e.g., 0V). If the determination result is yes, the control circuit 120 can determine that the SD card 20 is an SD Express card; otherwise, proceed to step S225.

[0088] Step S225: Control pin 18 to be essentially 0V (i.e., equivalent to turning off pin 18).

[0089] Step S226: Control pin number 14 to be 1.8V.

[0090] Step S227: Determine whether pin 9 is actually at a low voltage (e.g., 0V). If the determination result is yes, then the control circuit 120 can determine that the SD card 20 is an SD Express card; otherwise, the SD card 20 is not an SD Express card.

[0091] Figure 8 show Figure 3 A flowchart of an embodiment of step S15 includes the following steps.

[0092] Step S152: Control pin number 4 to be 3.3V.

[0093] Step S154: Provide the clock to pin number 5.

[0094] Figure 9 show Figure 3 A flowchart of an embodiment of step S23 includes the following steps.

[0095] Step S232: Send several SD commands to SD card 20 via pin number 2.

[0096] Step S234: Determine whether the expected response has been received. If the determination result is yes, the control circuit 120 can determine that the SD card 20 is a traditional SD card; otherwise, the SD card 20 is not a traditional SD card.

[0097] In some embodiments, the above-described SD commands and expected responses can be found on page 36 of the Secure Digital Card Specification, version 7.10 (available here: www.sdcard.org / downloads / pls / archives / ).

[0098] Figure 10 A flowchart showing another embodiment of the memory card type identification method of the present invention is displayed. Figure 10 and Figure 3 Similar, the difference lies in Figure 10 The process first determines whether SD card 20 is an SD Express card, and then determines whether SD card 20 is a UHS-II SD card; therefore, please refer to [link / reference needed]. Figure 3 To understand through discussion Figure 10 Details of step S16 will be provided below. However, step S16 differs slightly from step S11, and the details of step S16 will be explained in detail below. Figure 11 Let's have a discussion.

[0099] Figure 11 show Figure 10 A flowchart of an embodiment of step S16 includes the following steps.

[0100] Step S162: Control pin number 4 to be 3.3V.

[0101] Step S164: Control pin number 14 to be 1.8V.

[0102] Step S166: Control pins 1, 9, 2, and 5 are essentially at a low voltage (e.g., 0V). Note that in some embodiments, step S166 is optional.

[0103] Figure 12 A flowchart showing another embodiment of the memory card type identification method of the present invention is displayed. This process can be executed by a card reader 11A and includes the following steps.

[0104] Step S15: Perform the traditional SD card initialization procedure on SD card 20. Details of step S15 are shown in... Figure 8 .

[0105] Step S24: Determine whether SD card 20 is an SD Express card. If the result is yes, proceed to step S32; otherwise, proceed to step S25. Details of step S24 will be provided below. Figure 13 Let's have a discussion.

[0106] Step S32: Continue with the SD Express card initialization procedure (see the Secure Digital Card Specification for details).

[0107] Step S25: Determine whether SD card 20 is a UHS-II SD card. If the result is yes, proceed to step S35; otherwise, proceed to step S26. Details of step S25 will be provided below. Figure 14 Let's have a discussion.

[0108] Step S35: Control pin 4 to be essentially 0V and perform the UHS-II SD card initialization procedure on SD card 20 (see the Secure Digital Card Specification for initialization details).

[0109] Step S26: Determine whether SD card 20 is a traditional SD card. If the result is yes, proceed to step S33; otherwise, proceed to step S34. Details of step S26 will be provided below. Figure 15 Let's have a discussion.

[0110] Step S33: Continue with the traditional SD card initialization procedure (see the Secure Digital Card Specification for details).

[0111] Step S34: Same Figure 3 Step S34.

[0112] Figure 13 show Figure 12 A flowchart of an embodiment of step S24 includes the following steps.

[0113] Step S242: Send the SD CMD0 command to the SD card 20 via pin number 2.

[0114] Step S244: Send the SD CMD8 command to the SD card 20 via pin number 2.

[0115] Step S246: Determine if a CMD8 PCIe response has been received. More specifically, this step determines whether the "PCIe response" field in the CMD8 PCIe response indicates that the SD card 20 is an SD Express card. If the result is yes, the control circuit 120 can determine that the SD card 20 is an SD Express card; otherwise, the SD card 20 is not an SD Express card.

[0116] For information on SD CMD0, SD CMD8 commands, and CMD8 PCIe responses, please refer to page 81 of the All Digital Card Specification, version 7.10.

[0117] Figure 14 show Figure 12 A flowchart of an embodiment of step S25 includes the following steps.

[0118] Step S252: Send the SD ACMD41 command to the SD card 20 via pin number 2.

[0119] Step S254: Determine whether SD card 20 is an ACMD41 UHS-II SD card. More specifically, this step determines whether the "UHS-II status" field in the response of SD card 20 indicates that SD card 20 is a UHS-II SD card. If the determination result is yes, then control circuit 120 can determine that SD card 20 is a UHS-II SD card; otherwise, SD card 20 is not a UHS-II SD card.

[0120] For information on the SD ACMD41 command and the ACMD41 UHS-II SD card status, please refer to page 39 of the All Digital Card Specification, version 7.10.

[0121] Figure 15 show Figure 12 A flowchart of an embodiment of step S26 includes the following steps.

[0122] Step S262: Determine whether CMD8 and ACMD41 commands have been received from SD card 20. If the determination result is yes, the control circuit 120 can determine that SD card 20 is a traditional SD card; otherwise, SD card 20 is not a traditional SD card.

[0123] Figure 16A flowchart showing another embodiment of the memory card type identification method of the present invention is displayed. This process can be executed by a card reader 11A and includes the following steps.

[0124] Step S11: Perform the UHS-II SD card initialization procedure on SD card 20. Details of step S11 are shown in... Figure 4 .

[0125] Step S21: Determine whether SD card 20 is a UHS-II SD card. If the result is yes, proceed to step S31; otherwise, proceed to step S12. Details of step S21 are shown in... Figure 5 .

[0126] Step S31: Continue the UHS-II SD card initialization procedure (see the Secure Digital Card Specification for details).

[0127] Step S12: Control pin 4 is actually 0V and control pin 14 is actually 0V.

[0128] Step S15: Perform the traditional SD card initialization procedure on SD card 20. Details of step S15 are shown in... Figure 8 .

[0129] Step S24: Determine whether SD card 20 is an SD Express card. If the result is yes, proceed to step S32; otherwise, proceed to step S27. Details of step S24 are shown in... Figure 13 .

[0130] Step S32: Continue with the SD Express card initialization procedure (see the Secure Digital Card Specification for details).

[0131] Step S27: Determine whether SD card 20 is a traditional SD card. If the result is yes, proceed to step S33; otherwise, proceed to step S34. Details of step S27 will be provided below. Figure 17 Let's have a discussion.

[0132] Step S33: Continue with the traditional SD card initialization procedure (see the Secure Digital Card Specification for details).

[0133] Step S34: Same Figure 3 Step S34.

[0134] Figure 17 show Figure 16 A flowchart of an embodiment of step S27 includes the following steps.

[0135] Step S272: Send the SD ACMD41 command to the SD card 20 via pin number 2.

[0136] Step S274: Determine whether the SD card 20 has received the SD ACMD41 command. If the determination result is yes, the control circuit 120 can determine that the SD card 20 is a conventional SD card; otherwise, the SD card 20 is not a conventional SD card.

[0137] In summary, this disclosure also provides four types of memory card identification methods. Figure 3 , Figure 10 , Figure 12 and Figure 16 ). Figure 1 The device or circuit can use any of these four methods to determine the type of SD card 20.

[0138] Although the foregoing embodiments use traditional SD cards, SD Express cards, and UHS-II SD cards as examples, this is not a limitation of the present invention. Those skilled in the art can appropriately apply the present invention to other types of SD memory cards based on the disclosure of the present invention.

[0139] Since those skilled in the art can understand the implementation details and variations of the method invention disclosed herein through the disclosure of the device invention, repeated descriptions are omitted here to avoid redundancy, without affecting the disclosure requirements and implementability of the method invention. Please note that the shapes, sizes, and proportions of the elements in the foregoing figures are merely illustrative and intended for those skilled in the art to understand the invention, and are not intended to limit the invention. Furthermore, in some embodiments, the order of the steps mentioned in the foregoing flowchart can be adjusted according to actual operation, and they may even be performed simultaneously or partially simultaneously.

[0140] While the embodiments of the present invention have been described above, these embodiments are not intended to limit the present invention. Those skilled in the art can make changes to the technical features of the present invention based on the explicit or implicit content of the present invention, and all such changes may fall within the scope of patent protection sought by the present invention. In other words, the scope of patent protection of the present invention shall be determined by the claims of this specification.

Claims

1. A method for identifying the type of a memory card, used to identify the type of a secure digital card, wherein the pin numbering of the secure digital card conforms to a secure digital card specification defined by the Secure Digital Association, the method comprising the following steps: (A) Perform one of a Class II ultra-high-speed secure digital card initialization procedure and a secure digital fast card initialization procedure on the secure digital card, wherein, Determine whether the security digital card is either a Class II ultra-high-speed security digital card or a security digital fast card; (B) If the judgment result is negative, the number 4 pin of the security digital card is effectively set to 0 volts; (C) Pin number 14 of the security digital card is essentially 0 volts; (D) Performing either the Type II Ultra-High-Speed ​​Secure Digital Card initialization procedure or the Secure Digital Fast Card initialization procedure on the secure digital card; and (E) Determine whether the security digital card is a Class II ultra-high-speed security digital card or a security digital fast card; The security digital card was not removed between steps (A) and (D).

2. The memory card type identification method as described in claim 1, wherein, The steps for initializing this type of ultra-high-speed secure digital card include: The number 4 pin controlling this security digital card is actually 3.3 volts; and The number 14 pin that controls this security digital card is actually 1.8 volts.

3. The memory card type identification method as described in claim 1, wherein, The steps for determining whether the security digital card is a Class II ultra-high-speed security digital card include: Provide a first clock to pin number 7 of the security digital card; Provide a second clock to pin number 8 of the security digital card; and Provide signal STB.L to pin 11 and pin 12 of the security digital card.

4. The memory card type identification method as described in claim 1, wherein, The steps to determine whether the security card is the security fast card include: Provide a first clock to pin number 7 of the security digital card; Provide a second clock to pin number 8 of the security digital card; Pin number 1 of the security digital card is essentially a high voltage; Determine whether pin 9 of the security digital card is actually at a low voltage; and When pin 9 of the security digital card is actually at a low voltage, the security digital card is determined to be the security digital fast card.

5. The memory card type identification method as described in claim 1, wherein, When the security digital card is neither the Type II Ultra-High Speed ​​Security Digital Card nor the Security Digital Fast Card, perform the following steps: The number 4 pin that controls this security digital card is actually 0 volts; Pin number 14, which controls the security digital card, is actually 0 volts. Perform a traditional secure digital card initialization procedure on the secure digital card; and Determine whether the security digital card is a traditional security digital card.

6. The memory card type identification method as described in claim 5, wherein, The steps for determining whether the security card is a traditional security card also include: Send multiple commands to the secure digital card; and Determine whether an expected response has been received; Specifically, when the expected response is received, the security digital card is identified as such.

7. A method for identifying the type of a memory card, used to identify the type of a secure digital card, wherein the pin numbering of the secure digital card conforms to a secure digital card specification defined by the Secure Digital Association, the method comprising the following steps: Perform a traditional secure digital card initialization procedure on the secure digital card; and After the traditional security digital card initialization procedure, it is determined in sequence whether the security digital card is a security digital fast card, a Class II ultra-high speed security digital card, or a traditional security digital card.

8. The memory card type identification method as described in claim 7, wherein, The steps to determine whether the security card is the security fast card include: Send an SD CMD0 command to the secure digital card; and Send an SD CMD8 command to the secure digital card.

9. A method for identifying the type of a memory card, used to identify the type of a secure digital card, wherein the pin numbering of the secure digital card conforms to a secure digital card specification defined by the Secure Digital Association, the method comprising the following steps: Before determining whether the security digital card is a Class II ultra-high-speed security digital card, a Class II ultra-high-speed security digital card initialization procedure is performed on the security digital card. When the security digital card is not the second type of ultra-high speed security digital card, a number 4 pin of the security digital card is controlled to be essentially 0 volts, a number 14 pin of the security digital card is controlled to be essentially 0 volts, and a conventional security digital card initialization procedure is performed on the security digital card. Determine whether the security digital card is a security digital fast card; and If the security digital card is not the security digital fast card, determine whether the security digital card is a traditional security digital card.

10. The memory card type identification method as described in claim 9, wherein, The steps to determine whether the security card is the security fast card include: Send a CMD8 command to the secure digital card.

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