Electronic device with card interface
View Patent ↗When initializing a card-shaped device inserted in a card interface, operation mode acquiring means incorporated in an electronic device acquires operation mode information, stored in a register file incorporated in the card-shaped device, by a predetermined procedure using a predetermined pin. Operation mode setting means incorporated in the electronic device executes signal assignment on a plurality of data pins peculiar to an operation mode indicated by the acquired operation mode information, thereby switching a data transfer width, and allowing the card-shaped device to operate in the operation mode.
1. An electronic device in which a card-shaped device having a connector section is usable, the connector section being provided with connector pins, the electronic device including a card interface to be connected to the card-shaped device via the connector section of the card-shaped device, the card interface comprising:
a ground pin assigned as a ground signal terminal for supplying a ground signal to the card-shaped device;
a power pin assigned as a power signal terminal for supplying a power signal to the card-shaped device;
a clock pin assigned as a clock signal terminal for supplying a clock signal to the card-shaped device;
a command pin assigned as a terminal for: (i) transmitting a specific command to the card-shaped device and requesting an operation mode information designating an operation mode thereof; and (ii) receiving a response including the operation mode information requested by the specific command, the command pin being assigned as the terminal when the card interface is connected to the card-shaped device;
a first data pin assigned only as a terminal for a bidirectional data transfer; and
a second data pin assigned as a terminal for a bidirectional data transfer, when the operation mode information included in a response to the specific command designates a first operation mode corresponding to a memory card being used as the card-shaped device, and assigned as a terminal for transferring a predetermined signal other than data, when the operation mode information designates a second operation mode corresponding to an input/output card being used as the card-shaped device.
2. The electronic device according to claim 1 , wherein the predetermined signal informs the electronic device of a state of the card-shaped device.
3. The electronic device according to claim 1 , wherein the predetermined signal is an asynchronous interrupt signal which is transferred from the card-shaped device to the electronic device.
4. A card-shaped device to be used by an electronic device having a card interface, the card-shaped device including a connector section to be connected to the electronic device via the card interface, the connector section comprising:
a ground pin assigned as a ground signal terminal for receiving a ground signal from the electronic device;
a power pin assigned as a power signal terminal for receiving a power signal from the electronic device;
a clock pin assigned as a clock signal terminal for receiving a clock signal from the electronic device;
a command pin assigned as a terminal for: (i) receiving a specific command from the electronic device, requesting an operation mode information designating an operation mode of the card-shaped device; and (ii) transmitting a response including an operation mode information requested by the specific command, the command pin being assigned as the terminal when the card-shaped device is connected to the card interface of the electronic device via the connector section;
a first data pin assigned only as a terminal for a bidirectional data transfer; and
a second data pin assigned as a terminal for a bidirectional data transfer, when the operation mode information included in a response to the specific command designates a first operation mode corresponding to a memory card being used as the card-shaped device, and assigned as a terminal for transferring a predetermined signal other than data, when the operation mode information designates a second operation mode corresponding to an input/output card being used as the card-shaped device.
5. The card-shaped device according to claim 4 , wherein the predetermined signal informs the electronic device of a state of the card-shaped device.
6. The card-shaped device according to claim 4 , wherein the predetermined signal is an asynchronous interrupt signal which is transferred from the card-shaped device to the electronic device.