DYNAMIC PROTOCOL FOR COMMUNICATING COMMAND AND ADDRESS INFORMATION

• US 20120191943A1
• Filed: 08/29/2010
• Published: 07/26/2012
• Est. Priority Date: 10/13/2009
• Status: Abandoned Application

• Current Assignee: Rambus Inc.
• Original Assignee: Rambus Inc.
• Inventors: Ware, Frederick A.
• Application Number:
  US13/390,683
• Publication Number:
  US 20120191943A1
• Time in Patent Office: Days
• US Class Current: 711/211
• CPC Class Codes: G06F 13/1668 Details of memory controller
• CPC Class Codes: G11C 7/10 Input/output [I/O] data interface arrangements, e.g. I/O data control circuits, I/O data buffers
• CPC Class Codes: G11C 7/1072 for memories with random access ports synchronised on clock signal pulse trains, e.g. synchronous memories, self timed memories
• CPC Class Codes: G11C 7/22 Read-write [R-W] timing or clocking circuits; Read-write [R-W] control signal generators or management

Abstract

A dynamic serialized command and address (CA) protocol with cycle-accurate matching between the PHY interface and the DFI interface is described. This CA protocol facilitates the use of a common memory-controller control logic with different CA bus configurations. With this CA protocol, CA packets for different memory operations have different formats. The size and the position of the CA packets vary relative to boundaries of DFI clock cycles, and the CA packets can extend beyond DFI clock cycle boundaries. In addition, there are at least two possible formats for a read or write memory operation. The appropriate format is selected based on the immediately preceding memory operation.

Claims

1. A memory device, comprising:

a memory core including a plurality of memory cells; and

an interface circuit to receive a memory operation command that specifies a memory operation pertaining to an access of the memory core, wherein the memory operation command is specified in a packet that includes the memory operation command multiplexed with address information corresponding to the access; and

wherein a framing position marking the start of the packet is adjusted based at least on one prior received packet, received by the interface circuit.

2. The memory device of claim 1, wherein the interface circuit comprises a packet delineation mechanism to dynamically determine the format of the packet.

3. The memory device of claim 2, wherein the packet delineation mechanism determines the format of a received packet based at least on a corresponding memory operation specified in the packet.

4. The memory device of claim 2, wherein the packet delineation mechanism determines the format of a received packet based at least on the memory operation specified in an immediately preceding packet.

5. The memory device of claim 1, wherein the memory operation includes one of an activate, precharge, read, and write operation.

6. The memory device of claim 5, wherein memory operation commands specifying one of a read and write operation, are each specified using at least two packet formats.

7. The memory device of claim 1, wherein the packet includes an operation code specifying the memory access operation, wherein the operation code of the packet begins at a fixed position relative to a boundary of recurring time periods, each of which having a predetermined duration.

8. The memory device of claim 7, wherein the beginning of a respective packet is at a position before or after the beginning of the corresponding time period;

and

wherein the end of a respective packet is at a position before or after the end of the corresponding time period.

9. The memory device of claim 1, wherein the packet is of a first size and the at least one prior received packet is of a second size, wherein the first size is different than the second size.

10. A memory controller, comprising:

an interface circuit to transmit a memory operation command that specifies an access to a memory core of a memory device;

wherein the memory operation command is specified in a packet that includes the memory operation command multiplexed with address information corresponding to the access; and

wherein a framing position marking the start of the packet is adjusted based at least on one prior transmitted packet transmitted by the interface circuit.

11. The memory controller of claim 10, wherein the interface circuit comprises a packet formatting mechanism to dynamically determine a format of packets to be transmitted.

12. The memory controller of claim 11, wherein the packet formatting mechanism determines the format of a packet based at least on the corresponding memory operation specified in the packet.

13. The memory controller of claim 11, wherein the packet formatting mechanism determines the format of a packet based at least on the memory operation specified in an immediately preceding packet.

14. The memory controller of claim 11, wherein the memory operation is one of an activate, precharge, read, and write operation.

15. The memory controller of claim 14, wherein memory operation commands specifying one of a read and write operation, are each specified using at least two different packet formats.

16. The memory controller of claim 11, wherein the packet includes an operation code specifying the memory access operation;

and

wherein the operation code of the packet begins at a fixed position relative to a boundary of recurring time periods, each of which having a predetermined duration.

17. The memory controller of claim 16, wherein the beginning of a respective packet is at a position before or after the beginning of the corresponding time period;

and

wherein the end of a respective packet is at a position before or after the end of the corresponding time period.

18. The memory controller of claim 10, wherein the packet is of a first size and the at least one prior transmitted packet is of a second size, wherein the first size is different than the second size.

19. A memory device, comprising:

means for receiving memory operation commands using a serialized control and address protocol;

wherein a respective command is specified in a packet;

wherein at least two received packets have different sizes; and

wherein a framing position marking the beginning of a respective packet is dynamically adjusted based at least on one or more prior packets.

20. A memory controller, comprising:

means for transmitting memory operation commands using a serialized control and address protocol;

wherein a respective command is specified in a packet;

wherein at least two received packets have different sizes; and

wherein a framing position marking the beginning of a respective packet is dynamically adjusted based at least on one or more prior packets.

21. A system, comprising:

a bus;

a memory controller comprising a first interface circuit coupled to the bus and configured to transmit memory operation commands using a serialized control and address protocol; and

a memory device comprising a second interface circuit coupled to the bus and configured to receive the memory operation commands;

wherein a respective memory operation command is specified in a packet;

wherein at least two received packets have different sizes; and

wherein a framing position marking the beginning of a respective packet is adjusted based at least on one or more prior packets.

22. A method for receiving information, comprising:

receiving a signal that includes groups of bits formatted using a serialized control and address protocol as a packet; and

extracting information associated with memory operations from the groups of bits;

wherein, for a respective memory operation of the memory operations, there are at least two packet sizes; and

wherein a framing position marking the beginning of a respective packet is adjusted based at least on one or more prior packets.

23. A method for providing information, comprising:

encoding information associated with memory operations into groups of bits using a serialized control and address protocol; and

transmitting a signal that includes the groups of bits in a packet format;

wherein, for a respective memory operation, there are at least two packet sizes; and

wherein a framing position marking the beginning of a respective packet is adjusted based at least on one or more prior packets