Electronic control unit having single non-volatile memory for multiple central processing units and data retrieval method
First Claim
1. An electronic control unit comprising:
- a plurality of CPUs;
a single non-volatile memory; and
communication ports connecting the CPUs and the non-volatile memory with one another, wherein a first one of the CPUs is programmed to (a) check whether a second one of the CPUs is accessing the non-volatile memory before accessing the non-volatile memory, (b) send to the second CPU a notification that the first CPU will access the non-volatile memory when a check result indicates that the second CPU is not accessing the non-volatile memory, and (c) stop the notification to the second CPU after completing an access to the non-volatile memory.
1 Assignment
0 Petitions
Accused Products
Abstract
An electronic control unit for engines or vehicles has multiple CPUs and a single non-volatile memory such as an EEPROM. The CPUs are programmed to directly receive data from the EEPROM. The CPUs may be programmed to generate respective data retrieving commands when the EEPROM is not being accessed for data retrieval. In this instance, the CPUs execute respective system register initialization processing differently from each other after a start of power supply. For instance, the system register initialization processing of a first CPU is divided while the system register initialization processing of a second CPU is not divided. Alternatively, the CPUs may be programmed to generate a data retrieving command only from the first CPU and receive the retrieved data by both the first CPU and the second CPU at the same time.
-
Citations
23 Claims
-
1. An electronic control unit comprising:
-
a plurality of CPUs;
a single non-volatile memory; and
communication ports connecting the CPUs and the non-volatile memory with one another, wherein a first one of the CPUs is programmed to (a) check whether a second one of the CPUs is accessing the non-volatile memory before accessing the non-volatile memory, (b) send to the second CPU a notification that the first CPU will access the non-volatile memory when a check result indicates that the second CPU is not accessing the non-volatile memory, and (c) stop the notification to the second CPU after completing an access to the non-volatile memory. - View Dependent Claims (2, 3, 4, 5, 21)
-
-
6. An electronic control unit comprising:
-
a plurality of CPUs;
a single non-volatile memory; and
communication ports connecting the CPUs and the non-volatile memory with one another, wherein a first one of the CPUs is programmed to transmit a data retrieving command to the non-volatile memory, and both the first CPU and a second CPU are programmed to receive at the same time the same data from the non-volatile memory retrieved in response to the data retrieving command of the first CPU thereby to share the same retrieved data. - View Dependent Claims (7, 8, 9, 10, 22)
-
-
11. A data retrieving method in an electronic control unit having a first CPU, a second CPU and a single non-volatile memory, the method comprising:
-
generating a data retrieving command from the first CPU and notifying the second CPU that the first CPU transmits the data retrieving command to the non-volatile memory;
retrieving data from the non-volatile memory in response to the data retrieving command; and
receiving the retrieved data by at least the first CPU directly from the non-volatile memory. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20, 23)
-
Specification