Memory control device, semiconductor memory device, memory system, and memory control method
A technique for improving data security is provided. To be specific, in a memory system including an information processing apparatus and a semiconductor memory device, the semiconductor memory device has an interface section that transmits, to the information processing apparatus, data read out from a memory core according to a plurality of communication protocols having different signal transmission/reception methods. Based on a switch command inputted from the information processing apparatus, a communication protocol selection section inputs, to the interface section, a selection signal for selecting a particular communication protocol from the plurality of communication protocols.
1. A memory control device to control access to a memory core storing data therein, said memory control device comprising:
processing circuitry including:
communication protocol selection circuitry to select a communication protocol from a plurality of communication protocols having different signal transmission/reception methods, based on a first command input given from an external apparatus; and
data transmission circuitry to transmit, to the external apparatus, data read out from the memory core based on a read-out request given from the external apparatus, according to said communication protocol selected by said communication protocol selection circuitry,
wherein said data transmission circuitry transmits, to the external apparatus, data in which designation information designating the selected communication protocol is added to read-out data read out from the memory core in response to the read-out request given from the external apparatus, and
wherein said communication protocol selection circuitry selects said selected communication protocol based on said first command input issued by the external apparatus based on said designation information.
2. The memory control device according to claim 1 , wherein said processing circuitry further includes:
a plurality of encryption processing circuitry portions having different encryption methods; and
encryption processing selection circuitry to select an encryption processing circuitry portion from said plurality of encryption processing circuitry portions, based on a second command input given from the external apparatus,
wherein said data transmission circuitry transmits, to the external apparatus, data encrypted by the encryption processing circuitry portion selected by said encryption processing selection circuitry.
3. The memory control device according to claim 2 , wherein said plurality of communication protocols include a communication protocol by which the transmission to the external apparatus starts after the data encrypted by said selected encryption processing circuitry portion is allowed to be outputted to said data transmission circuitry.
4. A semiconductor memory device comprising:
a memory core storing therein data to be processed by an external apparatus; and
processing circuitry including:
communication protocol selection circuitry to select a communication protocol from a plurality of communication protocols having different signal transmission/reception methods, based on a command input given from the external apparatus; and
data transmission circuitry to transmit, to the external apparatus, data read out from said memory core based on a read-out request given from the external apparatus, according to said communication protocol selected by said communication protocol selection circuitry,
wherein said data transmission circuitry transmits, to the external apparatus, data in which designation information designating said selected communication protocol is added to read-out data read out from said memory core in response to the read-out request given from the external apparatus, and
wherein said communication protocol selection circuitry selects said selected communication protocol based on said command input issued by the external apparatus based on said designation information.
5. A memory system comprising an information processing apparatus and a semiconductor memory device, wherein said semiconductor memory device includes:
a memory core storing therein data to be processed by an external apparatus; and
first processing circuitry including:
communication protocol selection circuitry to select a communication protocol from a plurality of communication protocols having different signal transmission/reception methods, based on a command input given from the external apparatus; and
data transmission circuitry to transmit, to the external apparatus, data read out from said memory core based on a read-out request given from the external apparatus, according to said communication protocol selected by said communication protocol selection circuitry,
wherein said data transmission circuitry transmits, to the external apparatus, data in which designation information designating said selected communication protocol is added to read-out data read out from said memory core in response to the read-out request given from the external apparatus, and
wherein said communication protocol selection circuitry selects said selected communication protocol based on said command input issued by the external apparatus based on said designation information.
6. The memory system according to claim 5 , wherein said information processing apparatus includes:
second processing circuitry including:
command generation circuitry to generate a command that designates, to said semiconductor memory device, the communication protocol from said plurality of communication protocols; and
communication circuitry to perform data communication with said semiconductor memory device according to any of said plurality of communication protocols,
wherein said communication protocol selection circuitry of said first processing circuitry of said semiconductor memory device selects the communication protocol based on the command generated by said command generation circuitry.
7. A memory control method to control access to a memory core storing data therein, said method comprising:
selecting a communication protocol from a plurality of communication protocols having different signal transmission/reception methods, based on a command input given from an external apparatus;
transmitting, to the external apparatus, data read out from the memory core based on a read-out request given from the external apparatus, according to said communication protocol selected in said selecting; and
transmitting, to the external apparatus, data in which designation information designating the selected communication protocol is added to read-out data read out from the memory core in response to the read-out request given from the external apparatus,
wherein said selecting the selected communication protocol is based on said command input issued by the external apparatus based on said designation information.
8. The memory control device according to claim 1 , wherein said first command input from the external apparatus includes designation information designating a previously selected communication protocol.
9. The semiconductor memory device according to claim 4 , wherein said command input from the external apparatus includes designation information designating a previously selected communication protocol.
10. The memory system according to claim 5 , wherein said command input from the external apparatus includes designation information designating a previously selected communication protocol.
11. The memory control method according to claim 7 , wherein said command input from the external apparatus includes designation information designating a previously selected communication protocol.