JPH01276253A - Memory card and its system - Google Patents

Abstract

PURPOSE:To execute an action corresponding to the kind of cards and simultaneously, to recognize the kind of cards at any time at a main body equipment side by causing the main body equipment side to know a card kind recognizing signal when the memory card is mounted to main body equipment. CONSTITUTION:When a memory card 11 is mounted to main body equipment 12, positive and negative potentials are impressed to power source terminals 13a and 13b, as a result, a grounding potential is connected to terminals 17a and 17 for card kind recognizing signals, and a positive electrode potential is connected to terminals 17b and 17d. In such a way, a signal 0101 is impressed to the terminals 17a-17d for card kind recognizing signals, the signal is sent as the card kind recognizing signal to the main body equipment 12, and for example, the fact that the card at such a time is an SRAM card can be recognized. Thus, the kind of cards can be known to the main body equipment side.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a memory card equipped with, for example, a ROMSRAM and its system, and particularly relates to recognition of the type of the memory card.

(Prior Art and Problems to be Solved by the Invention) Conventionally, in this type of memory card, it has been common to use one type of card for the main device.

However, 1. In recent years, there have been many opportunities to use several types of memory cards with convertible connectors for main body devices. For example, for one main device, mask RO
M card, OTP card, SRAM card, EEFRO
Many types of memory cards, such as M cards, have come into use.

However, conventional memory cards do not have a structure that informs the main device about the type of memory card, and as a result, the main device cannot recognize what type of memory card is currently connected, leading to problems such as the following: was.

b) If the main device is configured to support a RAM card and a ROM card is installed, writing will be performed in the same way as in the case of a RAM card. in this case,
You think you have memorized the data, but it actually doesn't.

口) If the main unit is configured to support EEFROM cards and an SRAM card is installed,
Writing is performed in the same way as in the case of an EPROM card. In this case, a situation may occur where the information is erroneously written to the SRAM card or is not stored.

The present invention has been made to solve such problems, and an object thereof is to provide a memory card and its system that make it possible to notify the main device of the card type.

(Means for Solving the Problems) A memory card according to the present invention has a card type recognition terminal that sends a card type recognition signal corresponding to the card type to the main device when inserted into the main device.

Furthermore, it has a gate circuit that is provided between the card type recognition terminal and the power supply terminal and is turned on by the output of the output command from the main device. This gate circuit is conductive for a predetermined time after inputting an output command from the main device or while the output command is being input.

Further, the memory card system according to the present invention includes a memory card that includes a power supply terminal and a card type recognition terminal that sends a signal corresponding to the card type to the main device when inserted into the main device.

Furthermore, the main device includes a gate circuit whose output is connected to the power supply terminal and which becomes conductive in response to the output of an output command from the main device.

(Function) In this invention, when a memory card is inserted into the main device, a card type recognition signal corresponding to the card type is sent to the main device from the card type recognition terminal.

(Example) FIG. 1 is a diagram showing an embodiment of the present invention.

In the figure, (11) is a memory card, and (12) is a main device. (13) is a power supply line, (14) is an address line, (15) is a control line, (1B) is a data bus, and (17) is a card type recognition signal line. ) Signals are exchanged between the memory card (11) and the main device (12).

Figure 2 is an output circuit diagram of the memory card type signal, in which (13a) and (13b) are power supply terminals, (17a
) (17b) (17c) (17d) are card type recognition signal terminals, (21) is ground potential, (22)
is the power supply. As shown in the figure, the card type recognition signal terminals (17a) (17C) are connected to the ground potential (21), and the card type recognition signal terminals (17b) (1
7d) is connected to the positive electrode side of the power source (22).

FIG. 3 is a time chart showing the operation of FIG. 2.

For example, at time 11, the memory card (11) is transferred to the main device (
12), the power terminals (13a) (13b)
Positive and negative potentials are applied to as shown, and as a result,
A ground potential is connected to the card type recognition signal terminals (17a) and (17c), and a positive potential is connected to the terminals (17b) and (17d). In this way, card type recognition signal terminals (17a) (17b) (17c) (17
A signal (0101) is applied to d), and the signal is sent to the main device (12) as a card type recognition signal, so that it can be recognized that the card at that time is an SRAM card, for example.

Next, when the memory card (11) is removed at time t2 in FIG. 3, it returns to the potential state before attachment.

Here, the following examples are given as the card type recognition signal.

(17a) (17b) (17c) (1,7d) Mask ROM card 00 01 07P card 00 10 EEPROM card 00 1 l EPROM card 01 0 O 5RAM card 01 01 Fig. 4 relates to another embodiment of the present invention It is a block diagram of a memory card system, in which (19) is a gate circuit provided in a memory card (11). (41
) is a CPU, (42) is a ROM, (43) is a RAM, and (44) is an interface. Gate circuit (
19) through the interface (44).
Discontinuity is controlled.

FIG. 5 is a time chart showing the operation timing of the memory card system of FIG. 4.

When an output command is output from the CPU (41), an output signal is sent out via the interface (44), the gate circuit (19) becomes conductive, and a card type recognition signal similar to the embodiment shown in FIG. 2 is output. Send. Thereby, the main device (12) side can grasp the type of the inserted memory card.

After the gate circuit (19) maintains the conductive state for a predetermined time Δt, it returns to the non-conductive state again. It is like this,
The configuration described above eliminates the risk of leakage.

Furthermore, as shown by the broken line of the output command in FIG. If there is some margin, it may be made conductive only while the output command is being output.

FIG. 6 is a block diagram of a memory card system according to another embodiment of the invention. In this example, the gate circuit (
19) is provided on the main device (12) side.
This embodiment is only different from the embodiment shown in the figure, and otherwise has the same configuration and operates in the same manner.

(Effects of the Invention) As described above, according to the present invention, while the memory card is installed in the main device, the card type recognition signal can be notified to the main device, so that the main device can recognize the card type. In addition to being able to perform actions corresponding to the type of card, the type of card can be recognized at any time.

Furthermore, according to the present invention, the gate circuit is provided on the memory card or the main device side, and the card type recognition signal is sent out only after or while the output command from the main device is output. Power consumption is reduced and there is no risk of leakage.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a memory card system according to an embodiment of the present invention, FIG. 2 is a block diagram of a memory card type recognition signal output circuit, and FIG. 3 is a timing chart showing its operation. FIG. 4 is a block diagram of a memory card type recognition signal output circuit in a memory card system according to another embodiment of the present invention, and FIG. 5 is a timing chart showing its operation. FIG. 6 is a block diagram of a memory card type recognition signal in a memory card system according to another embodiment of the present invention. In the figure, (11) is the memory card, (12) is the main device, (17a) (17b) (17c) (17d
) is a card type recognition signal terminal, and (19) is a gate circuit. Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Patent Attorney Souji Sasaki

Claims (4)

[Claims] (1) A memory card having a card type recognition terminal that sends a card type recognition signal corresponding to the card type to the main device when inserted into the main device. (2) The memory card according to item 1, which includes a gate circuit that is provided between the card type recognition terminal and the power supply terminal and is made conductive by the output of an output command from the main device. (3) The memory card according to item 2, wherein the gate circuit is conductive for a predetermined time after inputting the output command of the main device or while the output command is being input. (4) a memory card comprising a power terminal and a card type recognition terminal that sends a card type recognition signal corresponding to the card capacity to the main device when inserted into the main device; an output is connected to the power terminal; A memory card system comprising a main device and a gate circuit that is rendered conductive by the output of an output command from the main device.