Control data storage apparatus and process

• US 20060123205A1
• Filed: 12/07/2005
• Published: 06/08/2006
• Est. Priority Date: 12/08/2004
• Status: Abandoned Application

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Ogura, Mamoru
• Application Number:
  US11/295,579
• Publication Number:
  US 20060123205A1
• Time in Patent Office: Days
• US Class Current: 711/154
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory

Abstract

Control data storage apparatus includes a memory section including a plurality of control data memory blocks to store control data. There is further provided a control section to determine a selected memory block to store control data by selecting from the control data memory blocks.

Claims

1. A control data storage apparatus comprising:

a memory section including a plurality of control data memory blocks to store control data; and

a control section configured to determine a selected memory block to store control data by selecting from the control data memory blocks.

2. The control data storage apparatus as claimed in claim 1, wherein the memory section includes first and second memory blocks, as the control data memory blocks to store control data;

and the control section is configured to check if there remain control data writable memory regions in the control data memory blocks, and to write control data into a control data writable memory region in the other of the first and second memory blocks if one of the first and second memory blocks is full so that there remains no control data writable region in which control data can be written.

3. The control data storage apparatus as claimed in claim 2, wherein the control section is configured to examine if the control data memory blocks are in a predetermined full state, and the control section is further configured to examine which block is a last updated memory block in which control data is written most recently, and to erase control data in one of the control data memory blocks other than the last updated memory block if the control data memory blocks are in the full state.

4. The control data storage apparatus as claimed in claim 3, wherein the control section is configured to judge that the control data memory blocks are in the full state when there remains only one control data writable memory region in the control data memory blocks.

5. The control data storage apparatus as claimed in claim 2, wherein the control section is configured to examine a condition of a key switch, and allow a writing operation to the memory section when the key switch is in an off state.

6. The control data storage apparatus as claimed in claim 1, wherein the memory section includes a flash memory which includes the control data memory blocks.

7. The control data storage apparatus as claimed in claim 1, wherein the control data storage apparatus is a vehicle electronic control apparatus adapted to be mounted on a vehicle;

the memory section includes the control data memory blocks to store control data to be used for control in the vehicle; and

the control section is configured to perform a control operation to control the vehicle by using the control data in the control data memory blocks.

8. The control data storage apparatus as claimed in claim 7, wherein the control section is configured to perform the control operation when a key switch of the vehicle is in an on state, and to update contents in the control data memory blocks when the key switch is in an off state.

9. The control data storage apparatus as claimed in claim 7, wherein the control section is configured to select, as a selected erase block, one of the memory blocks which is full so that there remains no control data writable memory region, and to erase contents of the selected erase bock.

10. The control data storage apparatus as claimed in claim 9, wherein the control section is configured to examine whether the memory blocks are in a predetermined full state, and to erase all contents in the selected erase block if the memory blocks are in the predetermined full state.

11. A control data storage apparatus for a vehicle, comprising:

a memory section including a plurality of control data memory blocks to store control data sets for control for the vehicle; and

a control section configured

to write a new control data set into a selected one of the control data memory blocks of the memory section to update control data,

to perform the control for the vehicle, by reading a control data set written most recently in one of the control data memory blocks, and

to clear one of the control data memory blocks.

12. The control data storage apparatus as claimed in claim 11, wherein the control section is configured to determine a selected erase block when the control data memory blocks are in a predetermined full state, the selected erase block being one of the control data memory blocks which is full so that there remains no control data writable memory regions in the selected erase block, and which does not contain a most recent control data set which is most recent at the time of judgment that the data memory blocks are in the predetermined full state;

and to erase all contents of the selected erase block.

13. A control data storage process, comprising:

determining a selected memory block to store control data by selecting one from a plurality of control data memory blocks in a memory section; and

storing control data in the selected memory block.

14. The control data storage process as claimed in claim 13, wherein the control data storage process further comprises:

checking the number of control data writable regions remaining in the control data memory blocks to produce a block erase request signal when the number of control data writable regions is smaller than a predetermined number;

determining a selected erase block in response to the block erase request signal, the selected erase block being one of the control data memory blocks which is full so that there remains no control data writable memory regions in the selected erase block, and which does not contain most recent control data which is most recent at the time of generation of the block erase request signal; and

erasing all contents of the selected erase block in response to the block erase request signal.

15. A control data storage apparatus comprising:

means for storing control data sets sequentially in control data memory blocks in a memory to update control data;

means for reading a most recent control data set from one of the control data memory blocks in the memory to perform a control operation;

means for examining whether the memory blocks are in a predetermined state; and

means for clearing one of the control data memory blocks when the memory blocks are in the predetermined state.

16. The control data storage apparatus as claimed in claim 15, wherein said examining means includes means for checking the number of control data writable regions remaining in the control data memory blocks to produce a block erase request signal when the number of control data writable regions is smaller than a predetermined number;

and said clearing means includes means for determining a selected erase block in response to the block erase request signal, and means for erasing all the control data sets in the selected erase block in response to the block erase request signal, the selected erase block being one of the control data memory blocks which is full so that there remains no control data writable memory regions in the selected erase block, and which is not a last updated memory block containing a most recent control data set.