JP2006119963A - Card system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a card system wherein performance is improved by improving efficiency of an initial setting process. <P>SOLUTION: In a host 10 connectable with various cards 11, registries [1]13, [2]14 each having a storage function is provided in addition to an application 10a, a file system 10b, a device controller 10c and a host controller 10d. The registry [1]13 stores information wherein a frequency of connection of the card 11 is stored in each kind of the card, and information about a command issuing period when setting an operation voltage of the card 11. The registry [2]14 accumulates card identification information of the connected card 11, card characteristic information and application-related information or the like, and stores them for the plurality of cards. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a card system, and more particularly to a technique effective when applied to a card system including a host corresponding to various cards.

  According to a study by the present inventor, the following can be considered regarding the technology of the card system.

  For example, SDIO (Secure Digital I / O) cards, SD (Secure Digital) memory cards, MMC (MultiMediaCard (registered trademark)) cards, and the like are known as compatible cards. The SDIO card is used, for example, as an external I / O device that implements a GPS (Global Positioning System) function, a Bluetooth function, and the like. An SD memory card (hereinafter, sometimes abbreviated as an SD card) and an MMC card are externally connected. Used as a memory device.

  The SDIO card and the SD card have an increased number of data pins and the like with respect to the MMC card, but have a specification in which upward compatibility is maintained by a pin arrangement or the like. That is, these cards can be driven by the same card slot, and there are host devices that can drive all these cards. When such a host device drives the card, it first recognizes the specification of the card connected to the card slot, and performs an optimal operation setting according to the specification of the card.

  By the way, as a result of the study of the card system technology as described above, the following has been clarified.

  For example, in the SDIO card standard, the SD card standard, and the MMC card standard, a certain process is required until the card is connected to the host and the host and the card can communicate at the application level. This is defined as the initial setting process. In particular, in a system that conforms to the SDIO card standard and can drive SD cards and MMC cards in addition to SDIO cards, the initial setting process in the SD mode and MMC mode is as follows: (1) The host identifies the type of card. And (2) a process in which the host sets the operating voltage of the card, (3) a process in which the host acquires information from the card, and (4) a process in which the host sets the communication mode of the card.

  Note that the SD mode and the MMC mode are operation modes defined by the SD card standard and the MMC card standard, and other SPI modes are defined. In general, the SD mode and the MMC mode are more preferable. Widely used. Hereinafter, the details of each initial setting process described above will be described.

(1) Process for Host to Identify Card Type FIG. 5 is a process flow diagram showing the process for the host to identify the card type in the card system of the technology studied as the premise of the present invention. In this process, the host issues a command that only responds to the card of the corresponding type to the card, and determines the type of the card based on the presence or absence of the response. As shown in FIG. 5, the command to be issued includes CMD5 (0) with an argument of 0 as a command corresponding to the SDIO card, ACMD41 (0) with an argument of 0 as a command corresponding to the SD card, and an MMC card. CMD1 (0) with an argument of 0 as a command corresponding to.

  If there is no response, the host must wait for the timeout time, so the time required for this process differs depending on the order of command issuance. In the standard, the timeout time is defined as 64 clocks, but in a general system, it is set to about several milliseconds in consideration of compatibility with each card, response delay, and the like. For example, when an SDIO card is connected, the system A that first issues CMD5 shown in FIG. 5 is efficient because this process is completed without waiting for a timeout, but commands are issued in the order of ACMD41 → CMD1 → CMD5. The issuing system B is not efficient because it waits for two timeouts. Usually, the order of issuing commands is fixed by the system.

(2) Process in which the host sets the card operating voltage FIG. 6 is a process flow diagram showing the process in which the host sets the card operating voltage in the card system of the technology studied as the premise of the present invention. The host and the card must operate at the same voltage, and this process is a process for setting the host to operate at the same voltage as the card. Hereinafter, description will be made in association with the numbers in FIG.

  [1] The host issues an operation voltage setting command (hereinafter referred to as CMDV) using the operating voltage (hereinafter referred to as WV) at which the host is operating as an argument. This command is CMD5 for an SDIO card, ACMD41 for an SD card, and CMD1 for an MMC card.

  [2] Upon receiving CMDV, the card analyzes WV and prepares to operate with WV.

  [3] The card checks whether or not the operation preparation is completed. If the operation preparation is completed, the process proceeds to the process [4] below. Otherwise, the process proceeds to the process [5] below.

  [4] If the card is ready for operation, the card clears the busy flag indicating that the operating voltage is being set.

  [5] The card transmits a response including busy flag information to the host.

  [6] The host receives the response.

  [7] The host analyzes the response and checks whether the busy flag is cleared. If it has been cleared, the process ends. If not cleared, the processes [1] to [7] are executed again.

  Although the time until the card becomes operable varies depending on the operating voltage and the card characteristics, the host normally repeats the processes [1] to [7] a plurality of times.

(3) Process in which the host obtains information from the card The host defines the card identification information for distinguishing individual cards, card characteristic information such as operating voltage and transfer size, etc. Get application-related information specific to the application defined in the application standard. Such information and its acquisition method differ between the SDIO card and the SD card or MMC card.

(3-1) SDIO Card FIG. 7 is a diagram for explaining an example of processing when acquiring information from the SDIO card in the card system of the technology studied as the premise of the present invention. As shown in FIG. 7, the host 70 acquires card identification information from the SDIO card 71 by using CMD3, CMD52, and CMD53. The acquired card identification information 70a includes RCA (Relational Card Address) as a simple identification ID and CIS (Card Information Structure) as a detailed identification ID.

  In addition, the host 70 acquires card characteristic information from the SDIO card 71 using the CMD5, the CMD52, and the CMD53. The acquired card characteristic information 70b includes an OCR (Operation Condition Register) indicating an operable voltage range of the card, a CCCR (Card Common Control Registers) storing information such as a transfer size, and an FBR (Function Function) storing function functions. Basic Registers).

  Furthermore, the host 70 acquires application-related information from the SDIO card 71 using the CMD52 and the CMD53. The acquired application related information 70c includes information related to applications such as GPS and Bluetooth defined in the SDIO card application standard.

(3-2) Case of Memory Card (SD Card or MMC Card) FIG. 8 illustrates an example of processing when acquiring information from the SD card or MMC card in the card system of the technology studied as the premise of the present invention. It is a figure for doing. As shown in FIG. 8, the host 80 acquires card identification information from the memory card 81 by CMD2 (or CMD10). The acquired card identification information 80a includes a CID (Card IDentification) register.

  In addition, the host 80 acquires card characteristic information from the memory card 81 by CMD9 or the like, and acquires application-related information by CMD18 or the like. The acquired card characteristic information 80b includes an OCR indicating a card operable voltage range, a CSD (Card Specific Data) register for storing information such as a transfer size, and the acquired application related information 80c. , Information such as FAT (File Allocation Table) for storing information related to the file system and RootDirectory is included.

(4) Process in which the host sets the communication mode of the card The host sets the communication mode based on the information acquired from the card. The mode setting method differs between the SDIO card and the SD card or MMC card.

(4-1) SDIO Card FIG. 9 is a diagram for explaining an example of processing when setting the communication mode of the SDIO card in the card system of the technology studied as the premise of the present invention. As shown in FIG. 9, the host 70 performs settings such as enabling the clock frequency, bus width, and function based on the acquired card characteristic information 70b. Further, based on the acquired application related information 70c, the CMD52 and the CMD53 perform interrupt acceptance from the function and setting of the operation mode specific to the function.

(4-2) In the case of a memory card (SD card or MMC card) FIG. 10 shows an example of processing when setting the communication mode of the SD card or MMC card in the card system of the technology studied as the premise of the present invention. It is a figure for demonstrating. As shown in FIG. 10, the host 80 performs settings such as a clock frequency and a transfer block size based on the acquired card characteristic information 80b, a file system mounting process based on the acquired application-related information 80c, etc. Performed by CMD24 and CMD25.

  The card can be actually used through the initial setting process as described above. However, such an initial setting process becomes a problem as it degrades the performance particularly in a system corresponding to a plurality of types of cards as described above and having a high card exchange frequency. Specifically, there are the following problems (1) to (3).

  (1) In the operation of identifying the type of card by the host, the order in which the host classifies the card is usually fixed for each system, so that the card to be used is a card that needs to wait for timeout as described above. If it is biased, a lot of time is wasted.

  (2) In the process of setting the operating voltage of the card by the host, the exchange of useless commands and responses is repeated until the card is ready for operation.

  (3) Even if the card has been connected in the past, each time the card is reconnected, information is acquired from the card, so that exchange of commands, responses, and data is repeated for the acquisition. .

  SUMMARY OF THE INVENTION An object of the present invention is to provide a card system capable of improving the efficiency by improving the efficiency of the initial setting process.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  The memory system according to the present invention includes a host capable of controlling a plurality of types of cards, and the host identifies the type of the connected card when any type of the plurality of types of cards is connected. The function of counting the number of times a plurality of types of cards are connected for each type of card, the function of storing the number of connections counted for each type of card, and the memory for identifying the type of card And a function for determining the order of issuing a plurality of types of identification commands respectively corresponding to a plurality of types of cards based on the number of connections for each type of card stored in the function.

  This makes it possible to issue the identification commands corresponding to each card, which are issued when identifying the card type, in an optimal order. Therefore, the time until the card is identified is shortened, and the initial setting process can be made efficient.

  Here, the function for determining the order in which the identification commands are issued is, for example, identification corresponding to the type of card in order from the type of card corresponding to the card having the largest number of connections stored in the function to be stored. A command is issued.

  In other words, when a card is connected, it is assumed that there is a high possibility that the type of card that has been connected so far is likely to be connected, and is issued in order from the identification command corresponding to this card type. I do. This probabilistically increases the possibility of identifying the type of the connected card at an early stage, and can improve the efficiency of the initial setting process.

  The function of counting and the function of determining the order in which the identification commands are issued can be realized, for example, by a device driver provided in the host performing program processing using a computer provided in the host. . In this case, since it can be dealt with by adding a software function, it can be easily realized.

  The memory system according to the present invention includes a host that controls the card, and the host stores a cycle when a command for setting the operating voltage of the card is issued to the card when the card is initially set. A function, a function of counting the time required to complete the setting of the operating voltage of the card, and a function of correcting the period stored in the function to be stored based on the counted time. .

  This makes it possible to optimize the command issuance period when setting the operating voltage, and to reduce the number of times of command transmission / reception normally required a plurality of times between the host and the card. Therefore, power saving and the like can be achieved, and the initial setting process can be made efficient.

  The memory system according to the present invention includes a host for controlling the card, and the host has a function of storing card identification information acquired from each card and various setting information corresponding to the card identification information for a plurality of cards, When the card identification information acquired from the card is included in the function to be stored when the initial setting of the card is performed, various setting information stored in the function to be stored corresponding to the card identification information is used. Thus, the initial setting of the card is performed. Otherwise, the various setting information is acquired from the card, and the acquired various setting information is stored in the storing function in association with the card identification information.

  Accordingly, when a card that has been connected at least once in the past is connected again, the efficiency of the process of acquiring information from the card can be obtained in the card initial setting operation.

  Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  A function that stores the number of connections for each card type in the host, a function that stores the command issuance period when setting the card operating voltage, and a function that stores various card setting information for multiple cards Etc., the initial setting process is made efficient in terms of time and power, and the performance of the card system can be improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted.

  FIG. 1 is a schematic diagram showing an example of the configuration of a card system according to an embodiment of the present invention. The card system shown in FIG. 1 includes a host 10 and a card 11, and the host 10 and the card 11 are connected by a command line 12a, a data line 12b, and the like. The card 11 is, for example, one of an SDIO card, an SD card, and an MMC card. The host 10 includes a registry [1] 13 and a registry [2] 14 in addition to the application 10a, the file system 10b, the device driver 10c, and the host controller 10d.

  The application 10a includes software for SD cards and MMC cards, such as an explorer having a function for operating folders and files, and an audio player having a music data playback function, a car navigation system, a digital camera, and the like. This is software for an SDIO card having a control function.

  The file system 10b is system software that converts data input to and output from the device driver 10c into a file so that the application 10a can handle the data as a file. Specific examples include those conforming to FAT (File Allocation Table) standards such as FAT16 and FAT32.

  The device driver 10c is software for managing transactions and command sequences and controlling the host controller 10d. In the present invention, the function for optimizing the initial setting process based on the information registered in the registry [1] 13 and the registry [2] 14 and the information on the newly connected card are further stored in the registry [1]. 1] 13 and registry [2] 14 are provided with the function of registration.

  The host controller 10d is hardware that receives control of the device driver 10c and performs command transmission, response reception, and data transmission / reception with the card 11 via the command line 12a and the data line 12b.

  The registry [1] 13 and the registry [2] 14 are configured as shown in FIG. 2, for example. FIG. 2 is a schematic diagram showing an example of a registry configuration in the card system of FIG.

  As shown in FIG. 2, the registry [1] 13 counts the number of connections for each type of the connected card, and stores the counted value (hereinafter referred to as a type counter value). A type counter storage area 13a and an average waiting time storage area 13b in which an average value (average waiting time) until the card becomes operable at a specified operating voltage are provided. The size of the registry [1] 13 is, for example, 16 bytes, and its contents are 4 bytes × 3 (= number of card types) in the type counter storage area 13a and 4 bytes in the average waiting time storage area 13b. .

  The registry [2] 14 includes a card identification information storage area 14a, and card characteristic information storage area 14b and application-related information storage area 14c as various setting information storage areas. For example, when the maximum number of connectable cards is 800, the size of this registry is 100 Kbytes on the premise of 128 bytes per card. The breakdown of 128 bytes is, for example, 32 bytes for the card identification information storage area 14a, 32 bytes for the card characteristic information storage area 14b, and 64 bytes for the application related information storage area 14c.

  The present invention is characterized by using such a card system to improve the efficiency of the initial setting process after the card is connected to the host until the host and the card can communicate at the application level. That is, efficiency is achieved by the following methods (1) to (3).

  (1) In the process of identifying the card type, the host refers to the type counter storage area 13a of the registry [1] 13 and, for example, issues an identification command in the order of the card type corresponding to the one with the large type counter value. By issuing, we will improve the efficiency drop due to the bias of cards used.

  (2) In the process of setting the operating voltage of the card by referring to the storage area 13b of the average waiting time of the registry [1] 13 and issuing an operating voltage setting command in the period of the average waiting time, Eliminate unnecessary commands and responses until the card is ready for operation, reducing power consumption.

  (3) When a card is newly connected, card identification information, card characteristic information, and application-related information are registered in the corresponding storage areas 14a, 14b, and 14c in the registry [2] 14. Then, when a card in which such information has been registered is connected again, the card characteristic information and application related information stored in the registry [2] 14 are loaded and referenced to obtain the card information. The exchange of commands, responses, and data is omitted to reduce time and power.

  More specifically, the above method can be realized by an operation as shown in FIG. 3, for example. FIG. 3 is a process flow diagram showing an example of the operation of the card system of FIG. The processing flow in FIG. 3 is realized by, for example, the device driver 10c in FIG. Note that software processing such as the application 10a and the file system 10b including the device driver 10c is executed by using a computer (not shown in FIG. 1) such as a microprocessor or a microcomputer provided in the host 10, for example. . Hereinafter, the processing flow of FIG. 3 will be described in association with the numbers in FIG.

  [1] The host 10 detects the card 11.

  [2] The type counter storage area 13 a is loaded from the registry [1] 13. When the size of the type counter storage area 13a of the registry [1] 13 is 4 bytes × 3 (= number of card types), the number of card connections is from 0 to the maximum FFFFFFFF′h (hexadecimal number) times. Can be stored.

  [3] It is considered that the type of card having the largest number of connections in the past has a high probability of being connected again. Therefore, a card identification command (identification command) corresponding to the card type having the largest type counter value is issued. For example, if the value of the type counter of the SDIO card is the largest, CMD5 that is a command corresponding to the SDIO card is issued (see FIG. 5). If there is no response as a result of issuing CMD5 (if it is not an SDIO card), an identification command corresponding to the card with the next largest type counter value is issued. Note that if there are two or more cards having the same type counter value, the priority order is SDIO card> SD card> MMC card.

  [4] After the card type identification is completed, the value of the corresponding type counter is incremented by 1, and the type counter storage area 13a of the registry [1] 13 is updated.

  [5] Load the storage area 13b of the average waiting time from the registry [1] 13. The average waiting time storage area 13b can store from 0 μsec to a maximum of about 10 sec if the size is 4 bytes in units of μsec.

  [6] Generally, the time deviation until the card becomes operable at a specified operating voltage is small. Therefore, an operation voltage setting command corresponding to the card type is issued in a cycle corresponding to the average waiting time. In parallel, the time required for setting the operating voltage is measured.

  [7] The actual time required for the processing of [6] (= R (N) μsec), the average waiting time loaded from the registry [1] 13 (= D (N) μsec), and various counters The average waiting time (= D (N + 1) μsec) is recalculated from the total value (= N), and the storage area 13b of the average waiting time of the registry [1] 13 is updated to the recalculated value. The update calculation is D (N + 1) = {R (N) + D (N) × N} / (N + 1).

  [8] Obtain card identification information (ID = X) from the card 11. Here, if it is an SDIO card, RCA and CIS are acquired by CMD3 and CMD52. In the case of an SD card or MMC card, the CID is acquired by CMD2 or CMD10.

  [9] Load the card identification information and various setting information from the storage areas 14a to 14c of the registry [2] 14. These pieces of information are 128 bytes per card. The contents are 32 bytes for card identification information, 32 bytes for card characteristic information, and 64 bytes for application related information.

  [10] Search whether the card identification information (ID = X) acquired from the card 11 is registered in the card identification information storage area 14a of the registry [2] 14.

  [11] If registered, the card characteristic information and application related information corresponding to (ID = X) are loaded from the registry [2] 14, and the information of the card 11 can be obtained without accessing the card 11. .

  [12] If not registered, the card 11 is accessed to obtain card characteristic information and application related information.

  [13] Card identification information, card characteristic information, and application-related information acquired from the card 11 are newly registered in the storage areas 14a to 14c of the registry [2].

  [14] The host 10 sets a mode for communication such as a clock frequency and a bus width in the card 11 based on the information acquired up to the processing of [13], and the initial setting process ends.

  With the configuration and operation described above, for example, the following effects can be obtained.

  (1) In the card initial setting operation, it is possible to improve the efficiency drop due to the bias of the cards used. That is, the process of [3] in FIG. 3 described above reduces the probability of waiting for a response timeout, and improves the efficiency of the process of identifying the type of card. As a result, the time can be reduced by about several milliseconds.

  (2) In the card initial setting operation, useless commands and responses until the card operation preparation is completed can be omitted, and the efficiency of the process of setting the card operating voltage can be obtained. That is, by the process of [6] in FIG. 3 described above, exchange of useless commands and responses when setting the operating voltage of the card is reduced, and power can be reduced.

  (3) When a card that has been connected at least once in the past is connected again, the efficiency of the process of acquiring information from the card in the card initial setting operation can be obtained. That is, the process of [11] in FIG. 3 described above reduces the exchange of commands, responses, and data repeated until the card information is acquired. In particular, when the mounting of the file system is omitted, since a read operation of about 10 Kbytes can be omitted, a time reduction of about several msec and an energy reduction of about several hundred μJ can be obtained.

  (4) The time shortened by (1) and (3) can be used in other functions of the product (decoding multimedia data, operation of SDIO function application, etc.).

  (5) With the above (2) and (3), it is possible to save power in the card system. In addition, the deterioration of the memory card can be prevented by reducing the data exchange.

  Next, examples of configurations and operations obtained by modifying (applying) the configurations and operations described so far are shown in the following (1) to (3).

(1) Example of Applying Probability Distribution to Registry [1] FIG. 4 illustrates an example of the configuration and operation when the probability distribution is applied to registry [1] 13 in the card system of FIGS. FIG. In the description of the card system of FIGS. 1 to 3 described above, an example in which the type of the card is identified and the operating voltage is set using the value of the type counter of the registry [1] 13 and the average waiting time as they are.

  Here, as shown in FIG. 4, the value of the type counter of the registry [1] 13 and the average waiting time are not used as they are, but the value of the type counter, the value of the random number (= N), the average waiting time, A random number value (= N ′) is input to a probability distribution function such as a binomial distribution or a Lorentz distribution, and the calculated results P and P ′ are used. As a result, it is possible to further improve the decrease in efficiency due to the bias of the cards used, and to further increase the accuracy of the waiting time when setting the card operating voltage. Such a method is particularly effective when the information registered in the registry [1] 13 is small. The random number may be generated using, for example, a random number used for the SD card CPRM process (encryption technology for protecting the copyright of digital content).

(2) Example of adding a user selection function when recognizing a card There may be a case where a user gives priority to a specific type of card according to an application or the like and wants to make an initial setting. In that case, by providing a dip switch or the like on the host 10, in addition to the functions described in the card system of FIGS. 1 to 3, a function that allows the user to select which card to prioritize and make initial settings is added. can do.

(3) An example of selecting a registry area corresponding to the system scale In recent years, a system having an area of several gigabytes when including a hard disk such as a PC (Personal Computer) such as a cellular phone or a built-in system having a small memory area. The card interface is installed in various systems. Therefore, it is possible to select a registry to be secured according to the scale of the system.

  For example, only a registry [1] 13 including a type counter storage area 13a and an average waiting time storage area 13b in FIG. In that case, the efficiency of the process of identifying the type of card and the process of setting the operating voltage can be improved only by using a 16-byte memory. In a system with abundant memory areas, for example, in the registry [2] 14 of FIG. 1, the number of support cards can be increased or the storage area 14c for application-related information can be expanded to increase the degree of efficiency.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  The card system of the present invention has many types at the time of initial setting, such as a host system compatible with an SDIO card having various functions and a host system compatible with a combo card having an I / O function and a memory module. The present invention is particularly useful when applied to a host system that requires identification of the card and acquisition of detailed information on the card, and is not limited to this. For example, an MS (Memory Stick) corresponding to an I / O card and a memory card The present invention is widely applicable to card systems in general, including host systems and host systems compatible with cards that are frequently exchanged.

In the card system by one embodiment of this invention, it is the schematic which shows an example of the structure. FIG. 2 is a schematic diagram illustrating an example of a registry configuration in the card system of FIG. 1. FIG. 2 is a process flow diagram showing an example of the operation in the card system of FIG. 1. FIG. 4 is a diagram for explaining an example of a configuration and an operation when a probability distribution is applied to a registry [1] in the card system of FIGS. FIG. 11 is a process flow diagram showing a process of identifying a card type by a host in the card system of the technology studied as a premise of the present invention. FIG. 5 is a processing flow diagram showing a process in which a host sets an operating voltage of a card in the card system of the technology studied as a premise of the present invention. It is a figure for demonstrating an example of the process at the time of acquiring information from an SDIO card in the card system of the technique examined as a premise of the present invention. It is a figure for demonstrating an example of the process at the time of acquiring information from an SD card or an MMC card in the card system of the technique examined as a premise of the present invention. It is a figure for demonstrating an example of the process at the time of setting the communication mode of an SDIO card in the card system of the technique examined as a premise of this invention. It is a figure for demonstrating an example of the process at the time of setting the communication mode of an SD card or an MMC card | curd in the card system of the technique examined as a premise of this invention.

Explanation of symbols

10, 70, 80 Host 10a Application 10b File system 10c Device driver 10d Host controller 11, 71, 81 Card 12a Command line 12b Data line 13 Registry [1]
13a Type counter storage area 13b Average waiting time storage area 14 Registry [2]
14a Card identification information storage area 14b Card characteristic information storage area 14c Application related information storage area 70a, 80a Acquired card identification information 70b, 80b Acquired card characteristic information 70c, 80c Acquired application related information

Claims (5)

A card system including a host capable of controlling multiple types of cards,
The host is
A function of identifying the type of the connected card and counting the number of connection times of the plurality of types of cards for each type of the card when any of the types of cards is connected. When,
A function for storing the number of connections counted for each type of the card;
When identifying the type of card, the order of issuing a plurality of types of identification commands respectively corresponding to the plurality of types of cards is determined based on the number of connections for each type of card stored in the function to be stored The card system characterized by having a function to perform. The card system according to claim 1,
The function for determining the order in which the identification commands are issued corresponds to the type of the corresponding card in order from the type of the card corresponding to the card having the largest number of connections for each type of card stored in the function to be stored. A card system characterized by issuing an identification command. The card system according to claim 1 or 2,
The function of counting and the function of determining the order of issuing the identification commands are realized by a device driver provided in the host performing program processing using a computer provided in the host. Card system. A card system including a host controlling the card,
The host is
A function for storing a cycle of issuing a command for setting an operating voltage of the card to the card when performing the initial setting of the card;
A function that counts the time required to complete the setting of the operating voltage of the card;
A card system comprising: a function of correcting a period stored in the function to be stored based on the counted time. A card system including a host that controls a plurality of cards,
The host is
The card identification information obtained from each card and a function for storing various setting information corresponding to the card identification information for a plurality of cards,
When the card identification information acquired from the card that performs the initial setting is included in the function to be stored when performing the initial setting of the card, the card is stored in the function to be stored corresponding to the card identification information. The initial setting of the card is performed by using the various setting information, and if not, the various setting information is acquired from the card that performs the initial setting, and the acquired various setting information is associated with the card identification information. A card system storing the function in the memory.